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Content

Bangladesh Power
Development Board

Extension of Barapukuria Coal Fired Thermal
Power Station by 250 MW (3rd Unit)
Tender Documents
Part B

Technical Requirements

Volume 1 of 2

1

B0 General Specification
0.1 Subject of Specification
0.2 General Auxiliary Systems
0.2.1 Purpose of the Plant
0.2.2 Site conditions- environmental conditions
0.2.2.1 Location of site
0.2.2.2 Transportation and access road for site
0.2.2.3 Meteorological condition
0.2.2.3.1 General
0.2.2.3.2 Rainfall
0.2.2.3.3 Temperature and humidity
0.2.2.3.4 Earthquake
0.2.2.3.5 Wind
0.2.2.3.6 Flood water level condition
0.2.2.3.7 Geological conditions
0.2.3 Layout
0.2.4 Configuration
0.2.5 General technical requirements of the Plant
0.2.5.1 Design requirements
0.2.5.2 Outline description of generating facilities
0.2.5.3 Main powerhouse including control building
0.2.5.4 Civil
0.2.6 Mode of operation
0.2.7 Environmental conditions and emission control
standards
0.2.7.1 Environmental conditions
0.2.7.2 Ambient standards and emission standards
0.2.8 Fuel
0.2.8.1 Characteristic of coal

2

0.2.8.2 Ash

3

0.2.9 Waste and waste water
0.3 Supply and Services
0.3.1 General
0.3.2 Scope of engineering services
0.3.3 Common equipment 'and services
0.3.3.1 General
0.3.3.2 Mechanical
0.3.3.3 Electrical, instrumentation and control
0.3.3.4 Civil
0.3.4 Packing and transportation
0.3.5 Documentation
0.3.5.1 Documentation with Tender
0.3.5.2 Documentation after award of Contract
0.3.5.3 Requirements for documentation::
0.3.6 Erection, commissioning and testing
0.3.7 Training of Employer's personnel
0.3.7.1 General
0.3.7.2 Training in the Contractor's country
0.3.7.3 Training at site
0.3.8 Spare parts, tools, appliances, and consumable
0.3.8.1 Spare parts
0.3.8.2 Tools and appliances
0.3.8.3 Consumables
0.3.9 Maintenance works
0.3.10 Options
0.3.10.1 Option: Later realization of Power Unit 3
0.3.10.2 Option: l-.Maintenance works of the whole
Plant
0.4 Interfaces

4

0.4.1 Limits of supply

5

0.4.2 Interfaces to existing facilities on site
0.4.3 Metering
0.4.4 Communication systems
0.5 Form sheets (Data Sheets)
0.6 General Technical Requirements
0.6.1 General requirements
0.6.2 Standards and codes
0.6.3 Plant and equipment identification (e.g. Power Plant
Coding System KKS)
0.6.4

Marking and labeling of crates and packages

0.6.5

Corrosion protection coaling and galvanizing

0.6.6

Vibration

0.6.7

Standardization of makes

0.6.8

Accessibility

0.6.9

Signs

0.6.10 Units of measurement
0.6.11 Ways, stairs, ladders, balustrades
0.6.12 Hazardous areas fire protection provisions
0.6.13 Maintenance isolation
0.6.14 Materials
0.6.15 Pre-service cleaning and protection of plant equipment
0.6.16 Mechanical equipment
0.6.16.1 Pumps
0.6.16.2 Piping and accessories
0.6.16.2.1 Standards and general
conditions
0.6. 16.2.2 Material and construction
standards
0.6.16.2.3 Bolts and nuts
0.6.16.2.4 Pipe supports and anchors
0.6.16.2.5 Cleaning at workshop

6

0.6.16.2.6 Cleaning at site
0.6.16.2.7 Wall boxes and collars
0.6. 16.2.8 Expansion and flexibility
Piping design criteria
0.6.16.3

Welding and heat treatment

0.6.16.4

0.6.16.4.1 Responsibility
Required documents

0.6.16.4.2
0.6. I 6.4.3

Welding procedure
qualification
Personnel qualification
Welding process

0.6.16.4.4
0.6. 16.4.5
0.6.16.4.6
0.6.16.5

Pre-heating and heat
treatment
0.6. 16.4.7 Documentation
Valves, steam traps, condensate
drainers,
safety valves, control valves

0.6.16.6 Insulation
0.6.16.7 Vessels, tanks,
heat exchanger
0.6.17 Electrical equipment and
works
0.6.17.1
0.6.17.2
0.6.17.3
0.6.17.4
0.6.17.5

Standards
Standard
Climatic

voltages
conditions

Inductive interferences
Color code system for
switchgear, for local
switching measurementcontrol-signaling
cabinets and for mimic
diagrams

0.6.17.6 Protection class for
electrical operational
equipment and control
and monitoring
equipment

0.6.17.7 Protective measures
0.6.17.8 Auxiliary equipment

0.6.17.9 Requirements for local
cubicles and local
housings for e.g.
switchgear, control,
measurement and
signaling equipment
0.6.17.10 Local control points and
level control
cabinets
0.6.17.11 T erminal boxes and terminal
cabinets
0.6.17 .12 Explosion proof equipment
0.6.17 .13 Keys and key cabinets
0.6.17. I 4 Electric motors
0.6.17.14.1 High voltage
motors
0.6.17 .14.2 Low voltage
AC motors
0.6.17 .14.3 Actuator drives
0.6.17.14.4 DC motors
0.6.17.14.5 Painting
0.6.17 .14.6 Protection
against
explosio
n
hazards
0.6.17.14.7 Frequency
converters
0.6.17 .14.8 Tests
0.6.17 .14.9 Motor list
0.6.17 .14.10 Labels
0.6.18 Instrumentation and control
0.6.18.1 Measuring units
0.6.18.2 Sizes of indicators, recorders,
etc.
0.6.18.3 Protection and safety interlocks

0.6.18.4 Special local conditions
0.6.18.5 Tests
0.6.18.6 Field equipment
0.6.18.6.1 Measuring
systems/tr
ansmitte rs
0.6.18.6.2 Flow
measurements
0.6.18.6.3 Temperature
measurements
0.6.18.6.4 Pressure
measurements

0.6. 18.6.5 Analyses
meas
urem
ents
0.6. 18.6.6 Level
meas
urem
ents
0.6. 18.6.7 Electrical
meas
urem
ents
0.6. 18.6.8 Position
meas
urem
ents
0.6. 18.6.9 Contact
devic
es
0.6.18.6.10 Vibration
meas
urem
ents.
0.6.18.6.11 Control
valve
s
0.6.18.6. 12 Actuators
0.6.18.6.13. Local
instru
menta

tion
0.6.18.7 Racks, junction boxes
0.6.18:8 Control cubicles
0.6.18.9 Programmable logic
controller
0.6.18.10 T ransmitter racks and
piping
0.7 Inspection and Testing
0.7.1 General
0.7.1.1 Workshop manufacturing
and pre-assembly
0.7.1.2 Works inspections
0.7.2 Testing during manufacturing
0.7.2.1 Material tests
0.7.2.2 Tests at site
0.7.2.2.1 General
remar
ks
0.7.2.2.2 Hydraulic
tests
0.7.2.2.3 Test runs and
functi
onal
tests
0.7.2.2.4 Visual
ins
pec
tion
,
che
cki
ng
of
dim
ens
ion

s,
test
inst
ru
me
nts
0.7.2.3 Manufacturing tests
0.7.2.3.1 Welding
0.7.2.3.2 Pressure
testin
g
0.7.2.3.3 Testing of
cor
rosi
on
pro
tect
ion

0.7.2.4 Mechanical equipment
0.7.2.5 Electrical equipment
0.7.2.6 Control and monitoring equipment

Table of Contents of the Tender Documents, Part B


Section B0: General Technical Specification



Section B I : Steam Generator Plant



Section B2: Steam Turbine Plant with Condensate and Steam System



Section B3: Coal Handling System



Section B4: Air and Flue Gas System



Section B5: Ash Handling System



Section B6: Water Storage and Treatment Systems




Section B7: Auxiliary Systems
Section B8: Electrical and Associated Works



Section B9: Instrumentation and Control Works



Section B 10: Communication, Clock and Surveillance Systems




Section B11: Civil Works
Section B12: Workshops, Stores and Vehicles



Annexes

General Specification

B0. General Specification
0.1 Subject of Specification
This section forms an integral part of the Tender Documents issued by the
Bangladesh Power Development Board, Dhaka.

0.2 General Auxiliary Systems
All the auxiliary systems needed
have to be designed accordingly.

for

the

trouble-free

operation

of

the

unit

The main auxiliary common systems are listed hereunder:
This list is not limited to the systems below, but the contractor has to
supply, erect and commission all the general auxiliaries necessary for the
operation of the unit at M.C.R:












Coal Processing and Coal conveyor system
Ash handling, ash transport and ash pond
Raw water system, dc-mineralized water and potable water
Waste water treatment system
Pressurized air system
Laboratory
Auxiliary closed circuit cooling system
The fire fighting system
All ancillary buildings and services
6.6 KV and 440/220 V switch-gear rooms
Switchgear room and "relay room'

0.2.1 Purpose of the Plant - intent
It is the intention of the Bangladesh Power Development Board to install a
thermal power plant unit for a total capacity of 250 MW at the Barapukuria
Steam Power Plant, in order to meet the electricity power demand.
The Plant shall be coal fired and equipped with reheater and all auxiliary
and ancillary systems.
The Contractor shall cover all works for the Engineering,
construction and commissioning of the whole Plant on a turnkey basis.

procurement,

In order to transmit the generated electrical power to 230 kV grid network
a step up power plant substation shall be included.
The boilers shall be open-air installed for firing with coal.
The steam turbine condensers shall be - water - cooled. In order to cool
the condenser cooling water, cooling towers shall be constructed.

The equipment of the Plant shall be designed in accordance with the requirements contained in the Tender Documents and as illustrated on the
Tender Drawings attached.
Highest
reliability
and
availability,
convenience
of
operation
and
maintenance, neat and orderly arrangement, are of utmost importance.
The functional requirements of the various systems and the pleasing
physical appearance of the completed Plant shall also be taken into
account.
Due care shall be undertaken concerning the environmental impact out of
the Plant and sufficient protective measures shall be incorporated in the
design of the Plant for envirolUl1ent protection especially on air pollution,
water pollution and noise. The environment protection measures shall be
done in accordance with the Environment Protection Guidelines of UNDP,
ADB, World Bank and Environmental Protection and Emission Control
Standards of Bangladesh.
In all instances, the listing of items of the Plant shall be understood as
general, and shall include upon completion, even if not specifically mentioned,
other
necessary
components
and
appurtenances
required
for
proper, continuous and reliable commercial operation of the complete
installation, including any and all auxiliary and ancillary systems.

0.2.2 Site conditions - environmental conditions
The following information on local conditions is investigated or compiled
by the Owner/Owner's Representative. The Contractor is hereby in no
way relieved from his duties of carrying out the investigations required for
satisfactory performance of his works, before issuing the Bid and during
execution of the works.

0.2.2.1 Location of site
Barapukuria power Plant site is located in flat land of the Northwestern
"corner" of Bangladesh at about 45 km east of the district headquarters of
Dinajpur, 20 km east to the border of India. The north-south gauge railway
passes through the east part of the site.
The site is located about 1 km north of the coal mine mouth under construction.
The only large industrial
residential complexes.
The nearest
administrative
of the site.

area

nearby

is

this

coal

mine

including

its

town is Phulbari, a Thana (Upazila) headquarter as primary
center of the country. Phulbari is located about 6 km south

The major railway junction and surrounding
16 km to site. The railway is connected to site.

township

Parbatipur

is

about

The Maddhapara Hard Rock Mining Project,
trial project is located 12 km east of the site.
To reach site from Dhaka
normal climatic conditions.

by

car

needs

a

separate

approximately

large

scale

6

7

-

indus-

hours

at

The closest airport to site is Saidpur. It takes about 1 hour by car from site
to the airport. The airport is in operation now.
Metalled
site.

road

is

connecting

Dinajpur,

Phulbari,

Parbatipur,

Saidpur

and

The area is situated at approximately 30 m over sea level. The groundwater
flow goes from north to south. For cooling, industrial and housing purposes of
the existing 2x125 MW plant, the ground water is being pumped from deep
wells gathering area at north of site. Discharge water from coal mine after
required treatment will be used as cooling water and the existing deep tube
well water will be used for potable water & demi water production of the
proposed 250 MW. The waste water/sewage water after suitable treatment
shall be dumped in a soakaway at the south site of site.
The bottom ash from the boiler and the fly ash from boiler &electrical
precipitator shall be dumped in a pond on site. These ashes shall be
transported wet and during the dry time of the year the ash shall be wetened
by water. The water leaving the pond shall be treated in such a way that it will
be suitable for irrigation or for pumping away to the nearby river Tillay.
A dry ash conveyor transportation and dumping system shall be considered
as an option.

0.2.2.2 Transportation and access road for site
Access road for site for the facility of transportation, a metal road from the
end of Parbatipur/ Fulbari up to Barapukuria Power Station site is being used.
Transportation for construction and erection material
In Bangladesh, inland transportation of all imported
rail and road.

materials

is

done

by

In general, the ordinary equipment and materials can be transported to
the requested places by road and rail. However, a bulk of heavy
equipment and machinery such as Generator Stator, Steam Drum and
etc. for the coal fired power Plant are difficult to transport to near the
project site other than waterway.
Loads probably more than 150 t will need to be transported for the Power
Plant. A scheme that the Contractor of the Power Plant may consider
most feasible would be to transport the equipment by river upto nearest
possible location and then to transport by rail or road.
The Contractor
tender.

shall

fix

up

the

transportation

possibilities

in

detail

for

the

0.2.2.3 Meteorological condition
0.2.2.3.1 General
Bangladesh has a subtropical monsoon climate and weather patterns are
governed by the south-east Asian monsoon system. The year can be
roughly divided into the rainy season from May through September and
the dry season from October through April. Meteorological information
relevant to the Barapukuria site is available from weather stations at
Dinajpur (880 41'E, 25° 38'N) and Rangpur (89° 15'E,25° 45'N). These
stations are about 30 km west and east respectively from the Plant site.
The data are available at Bangladesh Meteorological Department.

0.2.2.3.2 Rainfall
Rainfall from May through September contributes over 85% of the annual
total. However, rainfall intensives tend to be high and concentrated in acomparatively small number of heavy storms, even when monthly rainfall
figures are relatively low. The monthly precipitation data are as follows (in
mm):________________________________________________________________

Average in
Dinajpur

Average in
Rangpur

Peak
at one day

Maximum
per month

January

11

6

February

13

15

March

16

27

April

70

110

May

241

307

85

307

June

297

499

140

700

July

592

660

142

640

August

442

430

132

442

September

307

412

431

890

October

144

120

104

242

November

7

7

December

16

17

2,008

2,812

Annual

Note: Above mentioned data are very old, probably in the period of 1981- 1988

0.2.2.3.3 Temperature and humidity
The data of temperature and humidity are as follows:
(According to the temperature data in 1988, the maximum temperature is
40°C and the minimum temperature 10.6°C. The mean temperature is
about 25°C and relative humidity is generally high.)

Dinajpur
Max.
Temp. in
'88 (0C)

Rangpur
Min.
Temp. in
'88 (0C)

January

24.9

11.6

Feb.

27.5

14.2

March

33.5

April

Mean.
Temp.81
- 88 (0C)

18.4

Mean
Hum.'81
- 88 (%)

Max.
Temp. in
'88 (0C)

Min.
Temp. in
'88 (0C)

Mean.
Temp.8
1
- 88 (0C)

Mean
Hum.'8
1
- 88 (%)

70

25.3

11.7

16.8

79

70.9

61

29.0

145

19.0

71

13.5

25.4

54

33.7

12.6

23.6

63

40.0

10.5

28.0

57

37.5

16.8

26.5

69

May

36.3

19.0

28.2

70

35.6

20.8

.
27.3

79

June

37.5

23.8

29.0

76

36.3

23.9

28.7

84

July

34.0

23.0

28.5

82

34.1

22.5

28.4

87

August

36.7

22.1

29.3

82

32.4

26.2

28.8

85

Sept.

32.0

25.6

28.4

84

31.8

25.4

27.8

87

Octobe
r

31.5

22.2

27.5

76

31.4

22.6

26.2

84

Nov.

28.8

16.4

23.7

70

28.3

17.5

22.1

79

Dec.

26.5

13.1

72

26.0

14.1

18.3

81

Annual

32.4

17.9

71

31.8

19. 1

24.5

79

19.6
25.6

0.2.2.3.4 Wind
The wind in Barapukuria changes its direction according to seasons. The
wind tends to blow from the west, or in dry season from northeast and
from the east or the southeast in rainy season. The predominant wind
direction
is
generally
east-west.
The
wind
speed
is
relatively
moderate
and it is said that there is also a high proportion of calm days through the
year.

Monthly average prevailing wind speed (knots and direction/lknot = 0.514 mis)
Rangpur (1979988)

YE
AR
197
9
198
0
198
1
198
2
19&
3
198
4
198
5
198
6
198
7
198
8

JAN
SPD DIR
3

N

FED

MAR

S

D
I
R
N

SP
D

APL

S
P
D
6

DI
R
NN
W

SP
D

MAY

JUN

SP
D

DI
R

SP
D

5

D
I
R
S

3

S

5

E

4

E

3

JUL
SP
D

4

DI
R
S
E
S
E

E

3

S

n.
a.

4

4

W

4

N
E

4

E

3

4

N
E

3

S

S

W

5

4

W

5

W

S

W

4

E

4

E

4

E

4

4

N
E
N
E
N
E
NN
E
N
E
N
E

4

W

6

W

7

W

4

E

4

S
E

4

4

W

S

S

4

E

4

E

5

E

5

6

E

5

E

6

E

5

S
E

5

7

W

6

E

5

E

5

E

5

4
5
5
4
4

4
S

N
E
w

N
E

4

4

N
E

S

N
E

6

E

5

S
E

4

E

5

5

E

4

E

6

E

6

E

7

E

4

AUG
D
I
R
S
E
S
E
n.
a.
S
E
S
E

SP
D

S

6

S
E
E
S
E
S
E

5
4
n.
a.
5
3

6
5
5
5

D
I
R
S
E
S
E
n.
a.
S
E
S
E
S
E
S
E
S
E
S
E
S
E

SEP
SP
D
5

OCT

NOV

D
I
R
S

SPD
DIR
3

N

3

N

3

S

4

N
E

3

2

3

W

4

4

N
E
N
E

4

SPD
DIR

SP
D

E

4

5

S

5

S

5

5

S
E

4

E

5

N
E
N
E
N
E
N
E
N
E
N
E

1

E

5

N
E

5

E

4

4

E

4

E

4

4

4

S

5

N
E

5

N
E
N
E

3
n.a
.
3
4

n.
a.
N
E

4

4
4
3
5
4

4

2
2

Monthly average prevailing wind speed (knots and direction/1 knot - 0.514 m/sj

Dinajpur (1981 - 1988)

YEA
R

JAN
SPD
DIR

198
1
198
2
198
3
198
4
198
5
198
6
198
7

6
3

FEU
SP
D

N
W
N
W
N
W

MAR

APR'

SP
D

7

DI
R
N
W

DI
R

8

W

4

W

3

3

W

SP
D

MA\'
SP
D

8

DI
R
N
E

W

3

4

W

IUN
SP
D

7

DI
R
N
E

E

3

5

E

JUL
SP
D

6

DI
R
N
E

E

3

E

3

E

2

AUG
SP
D

2

DI
R
N
E
S
E

E

2

S

3

6

6
3

SEP

D
I
R
N
E
E

NO\'
DI
R

SP
D

2

D
I
R
N

2

W

2

SP
D

DI
R

SP
D

3

E

2

2

E

2

3

E

3

E

2

W
N
E

SP
D

5

2

W

4

W

4

W

3

E

3

E

3

E

2

E

3

E

2

S
E

2

E

2

3

W

3

W

5

W

3

E

3

E

2

E

2

E

3

E

2

E

3

E

2

N
E
N
E
N
E

2

W

3

W

5

W

3

E

3

E

3

E

3

E

2

2

E

2

E

2

E

2

2

W

3

W

3

E

3

E

2

E

2

E

3

E

4

2

E

2

E

2

N
E

2

2

S
E

ocr

S
E
E

2
2
2

2
3

198
8

2

W

2

W

4

W

3

E

2

E

3

E

2

S

2

S

2

S

2

N
E

3

N
E

2

2
4

0.2.2.3.5 Earthquake
General
Bangladesh is historically less affected by earthquakes. During the last some one
hundred years widespread damages were caused by only the Great Earthquake
of 1897 which had its epicentral tract in the Shillong plateau. Two other major
earthquakes, the Bengal Earthquake of 1885 and Srimangal Earthquake of 1918
caused severe damages only in limited areas surrounding their epicenters. The
present
geological
information
does
not
indicate
existence
of
seismically
active
faults within the country. However, north and east of Bangladesh, there are areas
of high seismic activity in India and Myanmar and earthquakes originating in
these areas affect adjacent regions of Bangladesh.

Seismic zoning map
According
to the
Final Report
on
"Seismic Zoning Map of
Bangladesh and
Outline
of
a
Code
for
Earthquake
Resistant
Design
of
Structures
(1979)",
Bangladesh has been divided into three seismic zones. The Seismic Zoning Map
of Bangladesh is shown in Annex. The northeastern part that includes the towns
of Sylhet, Mymensingh and Rangpur are in Zone I, the most active seismic zone
where earthquake shock of maximum intensity of IX of Modified Mercall Scale is
possible. Zone II includes the towns of Dinajpur, Bogra, Dhaka and Chittagong.
The project area is included in Zone II. The horizontal seismic coefficient = O. 15
g.
Code for earthquake resistant design of structures
The main aim of the code for earthquake resistant design of structures is to
ensure that structures are able to respond to shocks of moderate intensities
without structural damage. This code is meant only for normal buildings with
height no more than 200 ft. In case of taller building, a dynamic analysis must be
performed,
with
the
ground
acceleration
inputs
appropriate
for
the
probable
maximum intensity for particular zone. According to this code, the shear force at
the base of a building is given by the following formula:
v = Z.I.K.C.S. W
Where Z

I

: Importance factor
(1.5 for important facilities, 1.0 for others).

K

:

C

S

w

: Basic horizontal seismic coefficient (0.06 for Zone II)

Structural system factor
(varies 0.67 - 1.33 according to structural systems).

: Structure flexibility factor
(varies 0.20 - 1.0 according to the fundamental
time period of a building)
Soil foundation factor
(varies 1.0 - 1.5 according to the combination of soil
type and foundation type)
: Design vertical load
:

The maximum design horizontal seismic coefficient = 0.15 g shall be considered.

2
5

0.2.2.3.6 Flood water level condition
The elevation of the site area is geodetically higher than the other parts of
Bangladesh. Therefore, the flood damage is "less" than that of the other regions.
According to the resident in the vicinity of the site area, the maximum flood level
in 1988 was
less than one meter above the ground level of that time.
Accordingly, during construction of unit no. 1 & 2 the Plant area was filled approx.
2 m high from that ground level to protect the Plant facilities from the flood. For
the flood protection, the railway is situated on an embankment which is 1.5 m to
2.0 higher than the ground level.
Therefore major earthfilling is not required. However if ground level of any area of
the proposed plant is found lower, it shall have to be filled up to the level of
existing plant. Underground piping and cabling shall be installed in waterproof
ducts which shall be equipped with lighting and fire alarms and which shall be
accessible for the maintenance staff.

Geological conditions
The stratigraphical sequence
into the following groups:

has

been

divided

on

purely

litho

logical

grounds

Madhupur Clay (Recent - Pleistocene)
Dupi (Tila Formations)

-Upper (Pliocene)
- Lower (Pliocenelate Miocene)

Gondwana Group (Permian)

- Upper Coals Sequence
Seam VI Sandstone
Sequence
Seam VI
- Lower Sandstone
Sequence
Tillites
-

Dasement (Pre-Cambrian)
The outline of Madhupur Clay and Dupi Tila Formation are as follow:
Bulk Density : 1.91 - 2.19 t/m3
a)

Madhupur clay
The Madhupur Clay formation was found across the entire site beneath a thin soil
horizon. It varies in thickness between 3 and 15 m, but is generally 10-12 m in
thickness. Lithologically, the fonnation comprises series of firm and stiff silty clays
interlaminated and interbedded with silts and siIty sands. The silt and sand
horizons increase in frequency to the base of the formation. The geotechnical
and hydrogeological characteristics of Madhupur clay are summarized as follows:

2
6

Shear strength of Madhupur clay
Shear
Resistance Angle

Cohesion (kN/m3)

30~85

Permeability:

9.79 x 10 - 5 - 5 X 10 - 7 m/s

Ph:

6.8 - 7.4

o
CO
CO

Undrained multistage triaxial test

i

119

o

b)

Shear box test

17°~ 11.6°

Dupi Tila formation
Dupi Tila formation is divided into two groups, the upper and the lower.
The upper Dupi Tila formation is dominated by sands between 94 m and 120 m
in thickness. The lower Dupi Tila formation, which is dominated by clays, is
located In the southern part of the coal deposit area and not present in the power
Plant site.
The upper Dupi
into two main units:

Tila

formation,

with

the

average

thickness

of

107

m

is

divisible

The upper unit: average 65 m in thickness, of micaceous gray sands and gravels
with occasional bands of silt and clay. The lower unit; approximately 40 m in
thickness, of orangebrown, slightly micaceous sandstone, generally finer than the
upper unit with more frequent thin beds of slit and clay.

The geotechnical
and
hydrogeological
characteristics
upper Dupi Tila formation are summarized as follows:

of

the

upper

part

Bulk density: 1.92~2.00 t/m3
Shear strength of upper Dupi Tila formation
Cohesion (kN/m1)

Shear box test
Triaxial test

Shear Resistance
Angle
24.5°

Undrained multistage
Consolidated drained

62

2° - 4°


Unconsolidated undrained

16

27.5°

"3i
o

130

• These tests were carried out on undisturbed samples of cohesive materials such as silt or
clayey silt of the Upper Dupi Tila formation.

2
7

of

the

Permeability
No
permeability
test
has
been
permeability of this formation is
judging from its soil composition.

carried
out
for
considered larger

this
than

formation.
However,
the
that of Madhupur Clay,

pH: 7.2

Topographic conditions
The project area in Dinajpur district, between Phulbari and Parbatipur is situated
in the deltaic plain of the Jamuna and Padma Rivers. It is flat and its altitude is
about 30 m above mean sea level, which is relatively higher than the other areas
of Bangladesh.

0.2.3 Layouts
The
detailed
arrangement
shall
consideration of
easy maintenance,
interfaces to the power grid.

be
proposed
access, short

by
links

the
Contractor
for
piling and

under
cabling,

The plant area shall be developed upto existing plant level (if required). The ash
pond shall be lowered below the natural ground for about 3 m and shall be
provided with bud walls up to + 5 m above the natural ground. The park area
shall remain at about natural ground level with the exception of the outfall canal.

0.2.4 Configuration
One coal
the Plant.

fired

boiler

with

turbine

generators

represent

the

core

components

of

The cooling requirement of the Plant shall be accomplished by a wet cooling
tower system. For ash transport, the cooling tower blow down water shall be
used. But for commissioning fresh water is required.

0.2.5 General technical requirements of the Plant
0.2.5.1 Design requirements
The Plant shall be designed for base load operation. Also extended shorttime
operation and longer periods of part load down to synchronized minimum load
must be possible without restrictions.
The design lifetime of the Plant shall exceed 200,000 operating hours.
The thermodynamic process of the Plant
Contractor according to the proposed equipment.

is

to

be

optimized

by

the

Tenderer/

The Plant shall be built-up of one independently operable power unit.
An
economic
optimal
balance
between
investment,
maintenance
Plant availability (planned and unplanned outages) shall be proposed .

expenses

2
8

and

Redundancy concept
Due
to
the
block-wise
structure
of
the
Plant,
propose
only
1
x
100%
implementation
of
very
cooling
water
pumps,
compressors,
etc.,
but
by
no
water system.
These
moderate
investment
solutions
can
Contractor
proves
with
corresponding
spare
that
overall
an
optimum
economic
solution
will
100% solutions are preferable.

be
parts
result;

the
costly
means

Tenderer/Contractor
major
equipment
for
the
boiler

may
like:
feed

accepted
if
the
Tenderer/
and
maintenance
proposals
otherwise
3
x
50%,
or
2x

The Tenderer/Contractor shall

a) design and configure all components of the Plant
b) propose spare parts stock (spare part building and content)
c) propose maintenance works in such a way that:



unplanned outage time of power unit shall not exceed 1.7% of the time in a
calendar year
Unit is available during 99.2% of the time in a calendar year.

0.2.5.2 Outline description of generating facilities
a) Installed capacity

250 MW Net

b) Annual utilization factor

80%

c) Overall gross efficiency

38.0% (minimum)


d) Plant starting scope
e) Unit auxiliary consumption
f) Annual coal consumption

output

el. at Gen. terminal

/input

coal net calorific value
at all conditions of warm/hot or
cold.
6.3% (max.)
about 700,000 tons (approx.)

g) Ash disposal area (proposed) 3 75,000 m2
h) Design life time of the power Plant shall exceed 200,000
operating hours.

0.2.5.2 Main powerhouse including control building
The main powerhouse which includes the control complex need to be a multilevel
multi-area structure. It shall be a seismic proof building of conventional steel
braced
frame
construction
in
the
upper
portion
with
foundations
of
reinforced
concrete.

0.2.5.3 Civil

2
9

The area of the Power Station for protection against flooding is considered to befilled up to the existing
plant
level
(if
required)
to
protect
the
Power
Plant
against
the flood.
The coal storage area shall be paved. drained and partly covered. The drain shall
be discharged to the ash pond. The ash pond shall be excavated. fertile soil to be
stored aside and the pond shall be lined with clay. The ash pond overflow shall
be treated to meet the relevant standards and shall lead via outfall canal to the
Tillay river. Try ash storage shall be considered as an option.
The treated sewage water may be discharged to the Tillay river.
The ash pond and
fences and gates.

the

park

shall

be

separated

from each

other

and

the

Plant

by

shall be
operation

suitable for safe and economical
under
the
extreme
ambient
air.

0.2.6 Mode of operation
All the equipment and the facilities
continuous
and
also
for
short-time
water and coal conditions specified.
The design of
requirements:

the

Plant

shall

be

based

on

the

following

operation

and

dispatching

a) The power unit shall be capable of following the daily and seasonal demand
profile of the electrical network.

b) The

power generation shall be fully dispatch able within the technical limits
of the Plant to be specified by the Tenderer, but at least between 40% and
100% of the net power output of the Plant without supporting fire.

c) Full

compliance with the conditions of
within 40 - 100% of power unit's power range.

the

admissible

air

pollution

is

required

0.2.7 Environmental conditions and emission control standards
0.2.7.1 Environmental conditions
The present environmental conditions in Barapukuria are as follows:

a) Atmospheric quality
There are no industrial activities to pollute air within a radius of 10 km from the
planned Power Station site (except existing 2 x 125 MW coal fired units). Though
there are effects of automobile, etc. emission and smoke generated by burning
after harvesting and from houses, the air pollutant concentration is expected to
be at a very low level.

b) Water quality
As prospective raw water sources, Coal mine discharge water (for normal use)
and wells (during emergency case to meet at least 50% of total requirement) are
considered. Water quality is given in Annex.

3
0

c) Soil quality
The study team collected the soil (in the year 1998) from the site for analysis
and the results are as follows:
Analysis result of metal content in soil
MgO
Item
0.7
Barapukuria
soil

CaO

Na20

K2 0

0.2

2.2

%

0.2

Barapukuria
soil

6.5

7

12.

+

m

CM

pS/c

+

CO
0

Analysis result of water dissolving and pH of soil
Item
pH
Mg1
EC

B203
427

K+

mg/kg

Na
+

201

b3+

mg/kg
0.1

0.2

0.2

1.0

<0.
1

Latest soil analysis is to be done by the Contractor/ Tenderer.

0.2.7.2 Ambient standards and emission standards
The standard values are given in Annexes. The standard values for effluent are also
given in Annexes.

3
1

0.2.8 Fuel
0.2.8.1 Characteristic of coal
These data should be compared with new data which will be analyzed by the coal
mine and examined by the personnel of the Power Plant. After having further
investigation on the Barapukuria coal, the coal analysis data for the planning of the
boilers at the Owner/Owner's Representativeing stages should be finalized.
At the time being the proximate analysis (average characteristics of whole seam) is
as follows:
Net Calorific Value
Gross Calorific Value
Total moisture
Inner moisture
Fixed carbon

Ash Content

Volatile content

Sulfur

23.500 MJ/ kg
25.540 MJ/ kg
26.000 MJ/ kg
8.20%
1.71%
46.92%
50.24%
51.11%
17.81%
19.07%
19.40%
27.07%
28.98%
29.48%
0.16%

Air Dry Basis
Dry Basis
Receive basis
Air dry basis
Receive basis
Air dry basis
Dry basis
Receive basis
Air dry basis
Dry basis
Receive basis
Air dry basis
Dry basis
Dry basis

Ultimate analysis (dry ash free basis)

Carbon
Hydrogen
Oxygen
Nitrogen
Sulfur

83.0%
5.1%
9.4%
1.7%
0.77%
99.97%

0.2.8.2 Ash
At the time being the following ash analysis (oxides in ash dry basis) (mean % of
whole seam) is available:

Si02

54.4%

AI2O)

35.6%

Fe203

2.9%

Ti02

3.2%

Mn304

0.11%

eaO

0.56%

K20

0.66%

Na20

0.06%

MgO

0.18%

P20S

0.46%

SO3
0.13%
Ash fusion temperatures of seam Vi (mean °C)
(reducing atmosphere)

Initial Deformation

l,400°C

Hemispherical

l,400°C

Flow

1,400°C

0.2.9 Waste and waste water

Water supply of the Power Plant will be covered by Coal mine discharge water
(for normal use) and deep tube well water (during emergency case to meet at least
50% of total requirement). To cope with the water requirements of Power Plant
consumers it is necessary to install water treatment and storage facilities. The
design of the storage facilities shall consider especially start-up and routine
maintenance periods in the Power Plant and water treatment plant.
Chemical polluted wastewater and sewage wastewater has to be treated to
comply with the relevant wastewater emission standards. Chemically polluted
wastewater shall be discharged after treatment to the ash pond
The waste water from the ash pond shall be discharged to the Tillay river. The
water which will be discharged to the Tillay river shall be treated also. This water
shall be suitable to be used in the park for fountains as well as for irrigation
purposes.

0.3 Supply and Services
0.3.2 General
The scope of this Tender Specification covers all supplies and services required
for meeting the purpose of the complete Plant, even if these are not expressively
mentioned in the following.
The works include the following main components, where the detailed scope of
supply shall be seen in the corresponding sections as listed below:

Section B1
Section B2

Steam Generator Plant
Steam Turbine Plant with Condensate and Steam System

Section B3

Coal Handling System

Section B4

Air and Flue Gas System

Section B5
Section B6

Ash Handling System
Water Storage and Treatment Systems

Section B7
Section B8
Section B9

Auxiliary Systems
Electrical and Associated Works
Instrumentation and Control Works

Section B10

Communication, Clock and Surveillance Systems

Section B11
Section B 12

Civil Works
Workshops, Stores and Vehicles

Before purchasing of any material
component/system shall be approved
tive/Owner/Owner's Representative.

the
by

documentation for each major
the Owner/Owner's Representa-

0.3.2 Scope of Owner/Owner's Representativeing services
The Owner/Owner's Representativeing services of
complete specified plant and covers following services:

the

Contract

refer

to

the

The Contractor shall actively participate in drawing-up of all required licensing
applications.
All services shall be performed by the Contractor to effect the required permits to
commence the works and operate the Plant, including but not limited to:


clarifications with authorities



participation in all clarification meetings



boiler operation permission by independent authority



and all other services as required.

All fees required due to a split-up into multiple applications shall be covered by
the Contractor.

0.3.3 Common equipment and services
The following supplies and services are to be included in the corresponding
section prices.

0.3.3.1 General







material and personnel costs (e.g. for testing authority staff, BPDB and if
necessary also Owner/Owner's Representative's staff) for tests and inspections which are mandated by legislation
material costs for site inspections
declaration of conformity with Bangladesh requirements and markings for
all machines
Owner/Owner's Representativeing design of complete supplied equipment
including interface coordination
all as-built documents (on data carriers; data formats as requested by the
Owner/Owner' s Representative)



quality control plan and safety plan




complete documentation as set out in the tender specification
operating and maintenance manual in summary form (8 copies),
O&M manual



detailed operating and maintenance instructions (8 copies)



a maintenance program including a well proven maintenance management
system for track keeping of all maintenance for all systems and equipment
of the Plant.

0.3.3.2 Mechanical


All necessary pipelines, valves, actuators, suitable for commissioning,
operation and standstill in preservation



all required line warm-up systems



all connection and adaptation works for tie-in into general supply and/or
evacuation systems



all necessary vents, drains and rinsing connections as well as tundishes with
covers, as far as possible aggregated to common groups of on operating
level.



all connection elements, screws, bolts, nuts, including gaskets and seals as
necessary.



all temporary installations required for tie-in measures including postweld
heat treatment complete, inner cleaning, etc.



all temporary pipework as required during connection measures



check
their

of

required

rehabilitation

existing

where

they

structures,

plant

lie

the

within

components
scope

of

and

supply,

systems
or

and

definition

of

required measures in good time if they lie outside of the scope of supply


all support structures, hangers etc.



all base frames, mounting plates, grouted in parts, rag bolts, covers, etc.



all required steel parts embedded in concrete



all couplings and coupling guards for electric motors and other drives



all

lifting

(cranes,

equipment
hoists,

and

hoists

monorails,

(for

etc.),

repair

work

electrically

where

operated

loads
if

exceed

lifting

or

50

kg)

lowering

heights exceed 8 m


required safety equipment, pressure relief valves, etc.



all

thermal

and

noise

insulation

including

cladding

as

well

as

any

other

noise

attenuation measures


stairways, ladders, platforms, galleries and walkways to all plant components, including escape routes as necessary



all necessary steel structures, stairs, ladders on platforms weather protection



all required ventilation or air conditioning equipment for safe operation of
mechanical and electrical equipment, to be supplied



all necessary corrosion protection measures for plant components and
equipment stored or mounted on site up to the time of reliability test run



complete primer and top coatings conforming to color code, clarified with
the Owner/Owner's Representative/Owner/Owner's Representative



noise abatements measures



all corrosion protection and electric trace heating for outdoor installations
(e.g. gas ducts, etc.)



complete

labeling

Representatives

of

all

system

and

plant

components

in

plain

according

language

to

(English

the
and

Owner/Owner's
Bangla)

and

Power Plant Classification System Coding (PPCS)


all fire protection measures



all lubrication systems



initial

lubricant

filling

test

run,

the

Owner/Owner's

and

minimization

of

sufficient
lubricant

Representative,

lubricants
types
up

for

by
to

commissioning

screening
Provisional

and
Taking

and

reliability

coordination
Over

of

with
the

relevant Unit


provision

of

all

connections

and

temporary

pipe

work

for

live steam line


flushing of all other lines including disposal of the effluents; protection with

steam

purging

of

the

wood and/or plastic at all instrumentation and appendages to be installed
during construction


all standard accessories and auxiliary equipment which normally form part of
the scope of supplies



all tests, inspections and works acceptances as well as all certificates and
reports of these



exchange of filter elements following reliability test run up to Provisional
Taking Over of the relevant Unit



valve trims for purging and subsequent exchange



removal of any unused material from site



scaffolding for all work aboveground level



insurances.

0.3.3.3 Electrical, instrumentation and control
In general, the Power Plant shall be started up, operated and switched down
from the DCS.
The electrical instrumentation and control plant mainly, but not limited to, shall
consist of:
all local measurements and field control loops (thermometers, pressure
gauges, local regulating devices, etc.) as well as all instruments for reliability
test and checks.


all necessary electrical drives


complete installation material, that is wiring, cabling and piping material, all needed fastenings, conduits, brackets and other supports, including the cable trays



all required junction boxes and cubicles



all field control boxes.



all instruments mounted on instrumentation racks



street and other outdoor lighting



lightning protection



electrical earthling of the equipment



clarification

of

all

logic

interconnections:

sequence,

interlocking,

protection,

safeguarding for coordinated operation start-up/shut down of individual items
of equipment.

0.3.3.4 Civil


Soil investigations



all necessary surveying works


preparation of site, demolition works, removal of underground obstacles, if
any



site fill



earthworks, drainage, excavation and refilling works



roads and pavement



concrete and reinforced concrete works, masonry and earthing



water proofing works for pressing and non-pressing water



fire protection during construction



roofing (non asbestos)



plumbing



facade works/glazing works; non asbestos



non-load bearing walls/installation partitions/dry construction works


metalwork and blacksmith work/raised flooring/doors and gates/sheet
metalwork



flooring work



fire protection with plumbing; fire protector



corrosion protection



crane way works



air conditioning systems


potable water, service water and waste water, sewage water, storm water
(permanent and during construction), etc.



housekeeping during construction.(at least once a week total)



staff facilities during construction



Owner/Owner's Representatives office


transport of all dumping material to dump locations (at least once a week
total)



interpretation of soil bearing test



temporary fencing of construction site



permanent wall and fencing with security road

0.3.4 Packing and transportation


Suitable packaging and transportation of the entire scope of supplies


free construction site, on-site transportation and temporary storage
including inspections and, if necessary, ensuring the prerequisites for
transportation



transport insurance



disposal of packing and transportation material



customs clearance



crane or hoisting facilities at seaport, railway, road and site



transportation to site



unloading at site



transportation to the place of installation.

0.3.5 Documentation

0.3.5.1 Documentation with Tender
General


form of Tender (Data Sheets) to be completed by the Bidder



deviations from the Tender Specifications on data sheet B0/FA



if a consortial bid is submitted, documents on the consortial agreement



description of options and alternatives offered



completely filled in price, guarantee- and data sheets of the
specifications




list of proposed makes and vendors

reference lists for delivery and installation of plants of similar type and size


time

schedule

for

Owner/Owner's

Representativeing,

deliveries,

erection/installation, commissioning and Reliability Test Run


complete description of the plant offered including description of the
process and the equipment



layout drawings of the plant



dimensioned

drawings

and

sectional

views

of

the

principal

plant

components


schematics of the principal plant systems



general
operation
shutdown

descriptions
including

of

individual

description

procedures,

of

systems

start-up,

tendencies

and

shutdown

showing

descriptions
and

the



emergency

behaviour

boiler/steam generator, turbine, etc.
all other documents necessary for comprehension of the offered
plants and equipment


documents on the quality assurance system



training program and schedule for Owner/Owner's Representative's
personnel.



space requirement for construction site and equipment



maintenance proposal (section 0.3.9) with list of tools and appliances

of
of



lists of spare parts for warranty period, lists of spare parts for LTSA
period



spare part storage and supply policy



mobilization and demobilization schedule for construction equipment



method of transportation and unloading heavy cargo
Mechanical



flow diagram of all systems



performance diagrams of main pumps, compressors, fans, etc
•start-up curves for cold (all material on ambient temperature) and warm start
up to MCR of one Unit
Steam turbine and boiler



correction curves for variations in


power output with normal water temperature and pressure



part load chart

Generator
Detailed descriptions/references of the main components such as:


stator and rotor design



excitation equipment



cooling system



power chart (generator capability curve MW, MVAr, p.f.)



no load and short circuit characteristic

Boiler
Description for the equipment offered giving information about:


general outline of installation



extent of shop fabrication



indicating site fabrication required



ducting including expansion joints



insulation, as well as anchors and sheets and refractory



spray attemporator and its characteristic



mounting, valves and fittings, including all safety valves.



description of equipment for other control system, if applicable


NOx, CO, S02, etc. emission characteristic for coal operation versus load at
full load



Drawings


dimensioned
general
arrangement
of
boilers,
turbines,
ash
extraction,
pumps,
fans,
el.
precipitator,
mills,
conveyors,
transportation,
etc.
ducting
including
guide
vanes
and
expansion
joints,
damper,
isolator,
platforms,
stairs,
ladders
and
stack,
workshops,
chemical
laboratory
,
stores,
administration building, entrance, fence and all other structures



dimensioned front and side sectional elevations and sectional plan of the
boiler,
turbo
group,
showing
drum,
casing,
insulation,
access
and
observation
doors
and
all
tube
banks
and
all
accessories
(conveyors,
breakers,
etc.,
all
boiler
pressure
parts,
turbine/generator
details,
mill,
ash extractor, ash transportation, etc.



design of the membrane walls and supporting by buckstag



Graphs, correction curves for boiler



tentative start-up diagrams for cold start, warm start and hot start



material

diagram

temperature
and

showing

and

maximum

highest

material,
steam

admissible

dimensions,

temperature,

material

temperature

highest

design
and

exhaust

material
design

gas

temperature
pressure

for

components of the steam/water system


change of exhaust gas temperatures over load



variation of steam temperatures over the heating surfaces, stating materials employed

Electrical system


electrical single-line diagram



preliminary lists of motors and electrical consumers including power demand



auxiliary power requirement of the plants



arrangement of generator bus duct up to generator step-up transformer, HV
and star-point cubicles, unit auxiliary transformer



general arrangement of electrical equipment



I&C power supply


,

description

of

the

power

supply

system

for

DC/AC

systems(24

V

DC

and/or 230 V AC, redundancy, failure management, etc.)


DC and safe AC supply principles



detailed

explanations

to

be

given

for

the

DC

and

provided


construction power supply arrangement



general arrangement of 230 kV switchyard equipment
Instrumentation & Control system



control system architecture showing all components provided for this Power

safe

AC

principle

to

be

Plant in their structural arrangement


description of philosophy of the DCS with reference to


availability



redundancy concept



description of burner management and boiler protection system including
information about redundancy concept .



list of all subcontractors


reference list for the DCS with indication of plant type, system architecture
and size of the system



list of package system (black boxes)



Civil

architectural outline drawings for all buildings and building structures showing
the arrangement of the complete plans, inclusive of all levels and sections

site plan of the complete plant showing all buildings, building elements, roads,
landscaping etc .
schematic design of building
Maintenance
For boiler with accessories, steam turbine, generator and the total scope of supply
maintenance and overhaul charts should be submitted. Both major and minor plant
outages for inspection and/ or routine maintenance should be shown on the chart,
together with the nature of the work to be undertaken and the expected duration of
the outage. This information should also include all the auxiliary plant to be supplied
under the Contract.

0.3.5.2 Documentation after award of Contract
The documents required for design, construction, installation, operation and
maintenance of the entire plant shall be submitted by the Contractor in good time
so as to permit the plant as a whole to be erected in compliance with the
specified time table.
Only the most important documents are listed below. These documents shall be
submitted sufficiently in advance for approval before award of relevant order, so
that corrections and amendments desired by the Owner/Owner's Representative
as well as resubmission of the documents will not result in any delays with
respect to the guaranteed time table. The Owner/Owner's Representative
reserves the right to request from the Contractor additional drawings, documents,
etc. as may be required for proper understanding and definition of the design and
Owner/Owner's Representativeing of the Plant.
General



current list of drawings (to be updated every month)
progress reports (to be updated every month)



erection and installation progress reports (to be updated every month)



list of subcontractors/manufacturers for approval before purchasing



proposed inspection and testing programs for approval



detailed program for commissioning for approval



testing documents/report of results of all tests for approval



training program for approval



operating

and

equipment

maintenance

and

facilities

manual

(first

with

issue

3

description
months

and

before

instructions

start

of

for

all

commissioning

and second issue before trial run (2 weeks) - OMM for approval


as-built-documentation including drawings of all equipment



declaration of conformance with Bangladesh regulations



spare part lists for approval

Time scheduling, based on CPM


overall

time

schedule

commissioning
construction

for

broken
works,

design,

down

stating

for

dates

manufacture,

the
for

supply,

principal

completion

plant
of

assembly
components

any

preparatory

and
and
work

II
all
from

others which may be necessary.


detailed erection, installation and commissioning schedule



complete list of documents with proposed submission deadlines

Mechanical Owner/Owner's Representativeing; such as, but not limited
to:


arrangement

drawings

of

the

principal

components

with

ducts

and

platforms

layouts .


arrangement drawings of all auxiliary equipment (cubicles, etc.) and ancillaries



piping
of

and

instrumentation

pipelines

and

valves

schematics

and

stating

isometric

materials,

drawings,

)nominal

including

diameters,

lists

nominal

pressures, dimensions and insulation thickness of all pipes;


plans of main pipelines including location of cable routes



characteristics of pumps, fans, etc.



details

of

electricity,

required
steam,

auxiliary
chemicals,

energy

sources

instrumentation

and
air,

consumer
working

consumables
air)

(e.g.

with

condition

before

execution

data and consumption values


thermodynamic diagrams



start-up and shutdown diagrams with descriptions



welding

procedures

of the welding

(for

workshop

and

site),

to

be

approved



sectional and detail drawings of all components



for

all

lifting

operations

(repair,

maintenance,

etc.)

a

lifting

plan

has

to

be

submitted by the Contractor


limits of coal and fuel oil properties

Boiler and accessories


start-up charts from cold



start-up charts from warm



start-up charts from hot



general arrangement and section drawing of the casing, stack, etc.



detailed

arrangement

equipment

(flash

drawings

tank,

of

etc.)

all

equipment

complete

with

including

pipes,

cable

all

auxiliary

tracing,

steel

structures, cubicles, electric consumers, etc.


drawings and information for all relevant components such as



dimensioned details of drums and internals



boiler and ducting support and expansion joints



tube bank support details


list of insulation materials, showing type, location, protection, fastening
and surface temperature



boiler through flow schematics stating materials, temperatures etc.



graph of controlled and uncontrolled super heater steam temperature



diagrams, correction curves and drawings as well as p+i diagrams, etc

Electrical Engineering (Power Plant and 230 kV switchyard)


electrical single-line diagrams



list of motors and consumers



electric motors



starting

curves

(torque

of

motor

and

driven

machine,

time,

speed)

for

all

reports

of

motors of 50 k W and more


cable lists



standard circuit diagrams for all different kinds of electrical consumers



circuit diagrams for all individual electrical equipment



lists of equipment and devices



alarm lists and lists of measuring points



earthing plans with calculations



lightning

protection

plans

with

details

of

measuring

locations

measurements taken following commissioning


EMC concept with coordinated over voltage protection (NEMP level is not

and

required)


arrangement drawings of all electrical equipment



line plans of fire alarm system if applicable


arrangement

drawings

showing

exact

location

of

fire

alarm

devices

if

applicable


power and lighting installation plans



earthing and lightning protection plans and calculations



general arrangement drawings of the required cable trays, cable laying plans



dimensioned

drawings

and

erection

drawings

for

generator,

transformers,

switchgear, control panels, etc., including frontal and plan views


dimensioned drawings of generator auxiliary equipment



dimensioned
cubicles,

drawings
voltage

of

switching

regulation

cubicles,

cubicles,

generator

excitation

and

cubicles

star

etc.,

point
including

equipment configurations


calculation of mechanical stresses of switchgear rooms due to arcing faults



short

circuit

calculation

and

determination

of

protection

relay

settings

for

kV

substation.

All

the

equipment

is

generator protection and auxiliary electrical supplies under consideration
of protection of the entire system .


overall protection and metering diagrams for the whole protection equipment



generator charts and exciter characteristics

Construction power line (33 kV)
Contractor

will

use

Construction

Power

from

the

existing

33

arrangements shall have to be done by Contractor.
Instrumentation and Control


list of subcontractors



list of the overall- I&C equipment



list of spar parts



list of "black box" systems with indication of control systems to be used



schedule of workshop tests



manufacturer documents (manual, descriptions, etc.) for all I&C components



manuals for third party computer software



set

of

all

relevant

standard

specifications

to

which

manufactured


list

of

instruments

reference drawings


instrument location plans

including

code,

measuring

range,

alarm

and

limit

values,



instrument hook-up drawings



list

of

control

valves

including

operating

and

design

data,

materials,

makes,

types and reference drawings .


calculations for control valves, orifices, nozzles, etc.



Owner/Owner's
actuators),

Representativeing

control

dampers

drawings
(including

of

control

actuators),

valves

orifices,

(including

nozzles,

venturi

nozzles


diagram

of

control

system

architecture

showing

all

components

provided

for

this Power Plant in their structural arrangement


lists of I/O point assignment



list of alarms including settings



program listings for all application programs



logic diagrams



description for all functional group controls



description for all closed loop circuits



description for all safety and protection circuits



instrument loop diagrams



typical cabling diagram showing all cable connections in a typical manner



cable list including cable coding



cable routing plans



interior arrangement drawings of all cubicles



wiring and terminal diagrams for the entire I&C equipment



arrangement drawings of central and local control/electronic rooms



mimic diagrams for control panels and desks



detailed dimensions of panels, desks and cubicles



list of recorders



graphic displays for monitors of options.

Civil Owner/Owner's Representativeing


general

site

plan

of

the

entire

site

showing

all

buildings

and

installations,

traffic routes and landscaping etc.


architectural

arrangement

drawings,

design

layouts

and

itemized

drawings

(plans and sections) to scale 1: 1 00 of all buildings and plants


views of all sides of all buildings, scale 1: 100



architectural

drawings

of

each

floor

(plants,

sections)

including

all

necessary

whole

(existing,

detail drawings, scale 1 :50


arrangement
planned)

drawings

with

all

of

supply

the
and

external
disposal

plants

of

facilities,

the

site

roads

and

maneuvering areas, sewers, channels and culverts etc.


detailed constructive description of the single building with regard to the
structural design (structural systems, foundations etc.

as

a

vehicle

access

and



detailed specification of the buildings including information on materials and
qualities for execution



sectional elevations and roof plan



floating floors/systems



underground services and ducts with equipment appertaining to the services



layout of roads


principal details and sections for traffic areas, especially for ramps and
retaining walls



layouts for external works showing plants and fencing etc.



diagrams for ventilations



diagrams for supply systems of all buildings



schematic details for plumbing


structural drawings pertaining to outlet and inlet water channels and tie-in to
existing channels



foundations and other underground concrete works for the transformer area


civil drawings of roads and if applicable for up rated bridge over cooling water
outlet channel.

Especially for Workshops, Stores, and Laboratory:
Designation

Final

Preliminary

In weeks

In weeks

• Room sheets for all workshops, stores
and offices


Requirements
the

Documents

inventory

computer

the maintenance program from the
users' point of view


Program

Specification

i.e.

a

complete

verbal description of the inventory
program with logic diagrams


Test

Plan

describing

and

Procedures

how

describing

Documents

the

program

1
9

23

1
9

23
39

inventory

program

is to be tested
• Complete user manuals describing
how the user will run the program

29

33

and

Handbook of the computer program
language for managerial activities
Description of equipment suitable for
instructing computer operators
equipment for workshops,
stores and
vehicles with manufacturer's
name and
ad dress, equipment type
and
classification code

All documentation suitable for
maintenance of the complete Power
Plant equipment by the plant personnel
without any help of the manufacturer's
staff

65

Preventive maintenance schedules

20
after availability
of maintenance
instructions of
the
corresponding
suppliers

All documentation necessary for
ordering

87

Each and every spare part which may
be
necessary during the lifetime of the
Power
Plant down to IC, transistors, etc.
Proposal for first outfit with raw
materials
Spare parts list
List of all machines, apparatus and
other

2

43

9

23

17

39

26

Stock-keeping lists (including spare
part lists containing requisition



before provisional before provisional

taking over
taking over
Maintenance assembly and adjustment
,
drawings ^ ,

numbers, consumables, etc.



,„

before

As-built drawings

2

-

. . ,
provisional
taking over

at provisional
.,•
taking over

0.3.5.3 Requirements for documentation
Unless agreed otherwise, six (6) hard copies and three (3) sets of electronic copies
of all documents are to be submitted in English language for approval.
There shall be no installation and/or any commissioning activity without the relevant
documentation approved by the Owner/Owner's Representative.
The final documentation shall be submitted in English language.
Diagrammatic symbols for electrical drawings
Diagrammatic symbols complying with IEC 27, 34, 37 and 117 are to be used for
selling out the circuit and terminal layout.

0.3.6 Erection, commissioning and testing





Complete erection' of the total scope of supply up to operational readiness.
This includes mobilization and provision of the required supervisory staff,
skilled and unskilled personnel, as well as of installation scaffolding, cranes,
hoists, equipment and materials, personnel accommodation, prescribed tests
and inspections



commissioning and optimization of all plant components as well as
conducting all necessary measurements



supervision of erection, commissioning and Reliability Test Run of
complete supplied equipment

all testing as specified


operation, training of the Owner/Owner's Representative's staff and
maintenance up to Provisional Taking Over of the relevant Unit.

0.3.7 Training of Owner/Owner's Representative's personnel
0.3.7.1 General
During erection, commissioning and Reliability Test Run, the Owner/Owner's
Representative's operating staff is to be familiarized with the functions of the
system. In the training schedule, prior instruction of selected members of staff
shall be taken into account.
0.3.7.2 Training in the Contractor's country

The Contractor(s) shall train the Owner/Owner's Representative's operation
personnel on a power plant in operation, and at least in one major overhaul, of
similar technique (with reheat) and unit capacity and shall arrange the relevantagreement
with
the
Owner/Owner's
Representative/utility
company
of
the
power
plant in question. During training period one supervisory person from BPDB
headquarter should meet the trainees and review the progress in training.
In addition, the Contractor shall train the Owner's fire fighting personnel on the
premises/training centre of the subcontractor for the fire fighting equipment.
The contract price shall include the following expense
persons delegated by the Owner for total 100 person month:


for

twenty

one

(21)

the cost of return air tickets (economy class) from Bangladesh to the country
where the plant/fire fighting training centre is located



the cost of local transportation during the entire period



the cost of full board accommodation



the cost of special insurance as may be required



daily allowance at the rate of one hundred (100) US$.
The training shall be performed in the English language. Approval to detailed
training program shall be obtained from Owner before selection of trainees.
Sufficient handout and course materials in English shall be furnished to each
trainee so that he can use them as reference material after his return to Plant..

0.3.7.3 Class Room Training at site

The Contractor shall during construction, erection, testing and commissioning
of the Power Plant carry out comprehensive class room and on spot training
of the operation and maintenance personnel appointed by the Owner for the
Plant. 80% of the time shall be class room training, 20 % shall be on spot
training.


The Contractor shall submit a detailed training program subject to the
Owner/Owner/Owner's Representative's approval. This program shall include
a time schedule showing the duration of the individual lectures for the various
subjects and shall give descriptions of the single lecture subjects.



The Contractor shall, for a number of approximately eighty (80) trainees,
provide all necessary instruction material such as manuals, booklets,
pamphlets, drawings, sketches, models, static cutaway models, pictures,
photos, colour slides, films, projectors, etc. This instruction material shall be
in English language and become the property of the Owner.



All efforts shall be exercised by the Contractor to operate the Plant by the
Owner's
operation
personnel
under
the
Contractor's
supervision
and
guidance.



The Contractor shall furthermore
shooting and remedying of faults.



The instructors shall be capable of speaking and writing fluent English. These
instructors must have previous experience of providing training to a third country
having mother tongue other than English,

advise

the

Owner's

personnel

in

trouble

Before Provisional Taking Over, the Contractor has to demonstrate the success of
the trainees by demonstrating their ability to operate the Unit. The Owner/Owner's
representative has the right to refuse the trainers in case of non-adequacy with the
job requirements.

0.3.8 Spare parts, tools, appliances, and consumable
0.3.8.1 Spare parts
Spares as well as wear-and-tear parts shall cover those parts recommended by
the Contractor to enable the Plant to be operated for 05 years LTSA period after
completion of the guarantee time (final take-over). These parts shall be offered
on separate sheets.
Each spare part shall be labeled with its PPCS number.
All items shown in these schedules shall form part of the contract price and the
Owner/Owner's Representative may order all or any of the parts at his discretion
and adjust the contract price accordingly.
All spare parts required for testing of the Plant according to "Inspection and
Testing" and for all action before Provisional Taking Over Certificate form part of
the principal scope of supply and are not to be included in the spare parts list.
They shall be included in the scope of the relevant machinery without pricing, it
means for the time of commissioning, the trial operation and provisional takeover.
All spare parts required for warranty period (24 months) shall be supplied by the
Contractor.
Major items of spare parts must be priced individually but minor items can be
grouped together. The spare part shall be offered on separate price sheets.
The Contractor shall segregate in the schedule those "consumable" spares
necessary for the efficient day to day maintenance of any items of Plant, those
"spare parts" to be replaced after certain running time and those "strategic"
spares which, in his opinion the Owner/Owner's Representative should hold to
minimize the outage of the Plant due to breakdown.
Each item shall be labeled in BangIa and English as well as with PPCS coding
system and be separately packed against damage and sealed to prevent
deterioration from corrosion in a dry weatherproof building.
The spare parts shall be placed in bins, racks, drawers, shelves, cabinets, etc. to
be provided by the Contractor.
The Contractor shall not use any of the spare parts without written permission
from the Owner/Owner's Representative. The Contractor shall deliver the spare
parts for a 24-h-MCR-operation period of five (05) years LTSA. The stores shall
be suitable for these conditions.

0.3.8.2 Tools and appliances
The following tools and appliances shall be supplied under this Contract for use
by the Owner/Owner's Representative: ..

a) two sets of special tools and gauges required for the maintenance c1fthe Plant
b) one set of special lifting and handling appliances required for the

maintenance of the Plant.
Each tool or appliance is to be clearly marked with its size and/or purpose.
The tools and appliances supplied shall not be used for erection purposes by the
Contractor and shall be handed over in brand new condition.
The exception to this is the special lifting gear which may be used provided that
when it is handed over to the Owner/Owner's Representative it has not- been
subjected to more than normal wear and is still fully suitable for its intended use.
Each set of tools and appliances under category (a) shall be suitably arranged in
fitted boxes of mild steel construction, the number of boxes being determined in
relation to the layout of the plant and equipment in question. If the weight of any
box and its contents should be such that it cannot conveniently be carried, it shall
be supported on steerable rubber-tyred wheels.
Each cabinet and box shall be painted, fitted with a lock and clearly marked in
white letters with the name of the item of equipment for which the tools and
appliances contained are intended.
Suitable storage racks shall be provided for all portable lifting tackle in this
contract.
Suitable lifting lugs, ears or ring bolts, or tapped holes for lifting rings shall be
provided on all equipment items where the weight exceeds 15 kg.
All lifting tackle shall be stamped with a unique identification number and safe
working load. A test certificate from an approved Authority shall be supplied for
each item of lifting tackle.
The Contractor shall provide
appliances
being
supplied,
Representative.

a

schedule
for
the

of all lifting tackle
approval
of
the

and tools and
Owner/Owner's

The Contractor shall provide all runway beams, trolleys, lifting blocks, special
slings etc. necessary for the safe and efficient handling and maintenance of the
works. Particular attention shall be paid to high level equipment such as
deaerator. Electrically operated hoists and runway trolleys shall be provided for
all lifts in excess of 2.5 tons.
The tools and appliances with the appropriate storage racks, cabinets and boxes
shall be handed over to the Owner/Owner's Representative at the time of taking
over.
Where the Contract includes site erection, any special tools or appliances
required solely for erection shall be provided by the Contractor for his own use
and shall remain the property of the Contractor.
0.3.8.3 Consumables
Lubricants and greases

All lubricants proposed for the Plant operation shall be suitable for all operatingand
environmental conditions that will be met on site.

All oils and greases shall where possible be readily available in the country of
installation.
The number of oils and greases shall be kept to a minimum. For each type and
grade of lubricant recommended the Contractor shall list at least three equivalent
lubricants manufactured by alternative companies.
The Contractor shall supply the first fill of lubricants for the Plant, and shall
provide at the provisional Taking Over sufficient lubricants and greases
necessary for the efficient operation and maintenance of the Plant at full load 24
hours per day for a period of 24 months (Warranty period).
The Contractor shall also supply lubricants and greases necessary for the
efficient operation and maintenance of the Plant at full load 24 hours per day for
05 years LTSA period after final take over.
Chemicals and other consumables
The contract includes the provision of all chemicals, reagents, resins, and other
consumables required for testing, commissioning and setting to work of each
section of the Works.
The Contractor shall provide all chemicals, and other consumables required for
the efficient operation and maintenance of the plant at full load 24 hours per day
for a period of 24 months for each section of the works from the date of the
provisional Taking Over.
The Contractor shall prepare a list of these consumables giving
necessary for each section of the works and the recommended suppliers.

quantities

The Contractor shall deliver to site sufficient quantities of consumables in his supply
to allow for running of the Works prior to the issue of the Temporary Taking Over
Certificate. The delivery of the remainder of the consumables shall be programmed
to suit the operational requirements and space availability within the various stores.
The Contractor shall also provide all chemicals, and other consumables required
for the efficient operation and maintenance of the plant at full load 24 hours per
day for 05 years LTSA period after final take over.

0.3.9 Maintenance works
Deleted

0.3.10 Options
Deleted

0.4.1

Limits of supply
The interfaces for the Plant shall be as follows; all mentioned equipment,
connections, connection materials, counter flanges, shut-off valves, safety valves
are included in the scope of supply:

0.4 Interfaces

Interface
2x125 MW plant.

fuel

with

the

One
separate
nos.
of
coal
of
existing
coal
yard
shall
have
coal conveyor system.
Another
installed
yard.

coal
from

coal

conveyor

of

coal
conveyor
belt
crusher
unit
from
crusher
unit
upto
to
be
installed

conveyor
new

belt
coal

One
coal
processing
shall
have
to
be
stream
of
Weighing
scale
modifying coal conveyor system.

shall
yard
Plant
installed
of

existing
with

the
new
by

have
to

to
old

(Sorter
at
Coal

the
mine

02
upstream
coal
modifying
be
coal
machine)
down
by

Interface with BPDB existing substation.
Auxiliaries:
• auxiliary
switchgear
system
and
safe
extension
by
230 kV switchyard
feeders

busbars
AC
the

• terminal
cubicles
of
signals
for
extension
signals of future diameter extensions

(400
system)
required
status
and

V,
for
number
and
interfacing

DC
future
of
protection
of

Interface with 230 kV public grid:
For
SCADA
interface at switchyard and (control room).
For
instrumentation
control

and

PABX
building
Coal
source
cooling

communication
systems
raw
water,
industrial,
water

racks
building

potable
cooling

protection
within
cubicle

data

and
230
within

exchange
telephony
kV
Power

mine
discharge
water
of
raw
water,
water.
Proper
chemical
required.
Deep
well
water
will
backup. Deep wells having capacity 50% of

V24/28

at
switchyard

terminal
control

Plant

control

will
be
the
potable
industrial,
treatment
is
be
used
as

required quantity shall have to be installed.
Interface with Coal mine discharge water
and interconnection with existing deep well
system are required.

• sanitary waste water Interface out fall canal (including)
waste water, cooling After reuse for ash transportation up to the
tower blow down ash ash pond
pond water

After suitable treatment at irrigation nozzles
or outlet into the Tillay river

diesel fuel oil for Interface at unloading station
boiler
start-up,
emergency diesel
generator and fire
fighting pump diesel

0.4.2 Interfaces to project facilities on site
.


All refurbishment and adequate rerouting of
connecting roads and railways to the Plant
facilities
on site
roads
and
site in such a way that all material required
railways to the Plant site
for construction, commissioning and
operation of the Pant can be delivered to site
interfaces

x

..

to

existing

,

0.4.3 Metering
Sufficient metering devices shall be provided to enable an energetic balancing of the
power units and additionally to enable balancing of all process flows.
Metering of electrical signals is indicated in Annex C-B8-2, and frequency, voltage,
active power, reactive power, and energy shall be metered for each power unit at
the switchyard.
The accuracy and signal interface requirements for metering devices shall be
according to the Metering Code (which will be submitted by the Owner/Owner's
Representative during contract execution).

0.4.4 Communication systems
All communication to other subsystems and the plant systems shall be through
standardized interfaces.
CCTV shall be interfaced to the Power Plant's fire alarm system. CCTV shall be
provided with standard interfaces like RS-485/RS-232/ V-14/V-11.

0.5 Formsheets (Data Sheets)

Declaration by Bidder
(Form, to be completed by the
Bidder)
Deviation from Tender
Document (Form, to be
completed by the Bidder)

B0/F-1

B0/FA-1

Design Data
BPDB. BarapukuriaGuarantees
Power Plant 250 MW
Section B0: General Specification
Price Sheets (In Part A)
Declaration by Bidder
Time Schedule
Declaration by Bidder

ctionfor
B0: General Specification

viation from render Documents
BPDB. Barapukurla Power Plant
It is hereby confirmed that this Bid complies in full with
the Tender Document. Deviations are listed in detail in
the appended data sheet B0/FA. Should this Bid be
successful, beside the offered and agreed deviations
all of the conditions and stipulations of the Invitation
for Bid for 250 MW Barapukuria Coal Fired Power
Station Project will be accepted.

Bidder:

Bid Number:

Stamp and Signature of Bidder:

B0/F-1

B0/FD-1

Bidder/Contractor

B0/FG-1 to 14

Bidder/Contractor
B0/FZ-1

BPDB, Barapukuria Power Plant 250 MW

Bidder/Contractor

Section B0: General. Specification
Design Data - List of Major Equipment and Service
Suppliers

Unit

Data

(to be completed by the Bidder)
• Steam generator

• Steam turbine

• Steam turbine Generator

• Feed pumps, Cooling water pumps, Condensate
Pumps, fire fighting pumps

• Switchgear, Switchyard, Transformers

• Distributed control system

• Construction

• Maintenance

• Civil Contractor

-

• Compressor Station

• Emergency diesel
B0/FD-1

Guarantee Schedule
BPDB, Barapukuria Power Plant 250 MW

6 B0/FG-1
0

Section B0: General. Specification

Unit

Net Power Output, Po

kW
kJ/ kWh

Net Heat Rate:
Net heat rate based on net calorific value of fuel at
site condition (350 C, 1.013 bar, 98% RH)

Guarantees, to be completed by the
Bidder

at 100%
Load
(H-100% )

at 75% Load
(H75%)

at 50% Load
(H50%)

Days

Date of Completion of ICO:
From Effective date of Contract, Initial Commercial
Operation shall be completed within

Cold startup(from ambient temp.) starting time:

Hours

Time required from start command to 3000 rpm
Hours

Warm startup(after 8 hours shutdown) startina
time:
Time required from start command to 3000 rpm

Hours

Hot startup (after 2 hours shutdown) startina
time:
Time required from start command to 3000 rpm

Hours

Cold startup(from ambient temp.) loadina time:
Time required from synchronization to reach full
load

Hours

Warm startup(after 8 hours shutdown) loadina
time:
Time required from synchronization to reach full
load

Hours

Hot startup (after 2 hours shutdown) loadina
time:
Time required from synchronization to reach full
load

Performance Correction Curves
Characteristic
Curves
which
are
necessary
for
correcting Net Power Output, Net Heat rate from
the ambient condition to the Guarantee reference
condition shall be furnished by the Bidder.

Definition of "Net Power
Tender Document Part A.

Output"

and

"Net

Heat

Rate"

are

mentioned

in

General

condition,

6 B0/FG-1
1

BPDB, Barapukuria Power Plant 250 MW

Minimum Requirements

Section B0: General. Specification
Guarantees, to be completed by the Bidder

Unit

Data

year

2

General Guarantees
The Works conform to the Specification and shall be
free from defects in design, Owner/Owner's
Representativeing, materials, construction and
workmanship.
The. Plant furnished hereunder, and all materials,
equipment, tools and supplies incorporated therein
or becoming a part of the supply shall be new,
unused and shall be fully suitable for the intended
use, and shall meet all of the performance
requirements set forth in the Contract.
The Plant shall be fully suitable for use of the
specified fuel.
The Plant and all portions thereof shall be suitably
coordinated as to functions and interrelations,
properly responsive to controls and sufficiently stable
in operation to avoid objectionable fluctuations in
operating temperatures, pressures, rates of flow and
the like during all stages of operation.
Warrantee period

6 B0/FG-1
2

BPDB, Barapukuria Power Plant 250 MW

Minimum Requirements

Section B0: General Specification
Guarantees, to be completed by the Bidder

Unit

Data

Guarantee Data
Data to be guaranteed for the whole load range and
complete range of ambient conditions
Absence of excessive vibration during
turbine
generator.
Maximum
effective
measured at bearing housings:

operation
vibration

of the
velocity

Maximum vibration of components:
(vibration criteria as per guide line ISO 10816) .
Maximum noise pressure level at 1 m distance from the
noise source

"good", according
to VDI rule 2056

-

dB{A)

85

Maximum noise pressure level within workshops

dB{A)

75

Maximum noise pressure level within central control room

dB{A)

55

Maximum noise pressure at the boundary of the plant

dB{A)

60

Maximum heat losses of insulation
(Maximum residual oxygen content in the condensate downstream condenser and feed water downstream feed water
tank within the load range 25% to 100%

W/m2

200

mg/l

0.02
to be in accordance with
IEC regulations

Guarantees and tolerance values of generator,
transformers and electrical equipment
Maximum continuous boiler steam output

%

104 of turbine MCR flow

Steam temperature at superheater outlet

°c

535

Steam temperature at reheater outlet

°c

535

%of MCR

60 -100

% of MCR

70 -100

% of MCR

30

Constant steam temperature turndown range for the
superheater
Constant steam temperature turndown range for the
reheater
Minimum permissible load
Output of make-up water plant

m3/h

Maximum fresh water demand from deep wells

m3/h

6 B0/FG-1
3

BPDB, Barapukuria Power Plant 250 MW
Section B0: General Specification
Guarantees, to be completed by the Bidder

Minimum Requirements
Unit

Guarantee Conditions
Fuel coal net calorific value (LHV)
Fuel coal Gross calorific value (HHV)
Ambient air temperature (dry bulb)
Relative humidity
Power factor
Maximum temperature rise in generator windings
according to IEC 34.1, Class B

Data

kJ/kg
kJ/kg
°C
%
-

23,500
25,560
26
70
0.85

-

Correction curves for deviations in operating
conditions, drwg. Nos
Electrostatic precipitator efficiency on the
basis of the specified coal

%

99.5

Condition A: Maximum Continuous Rating
Live steam flow
Live steam pressure at boiler outlet
Live steam temperature at boiler outlet
Reheat steam temperature at boiler outlet
Cooling water flow
Cooling water temperature at cooling tower outlet
Gross output (at generator termional)
Gross specific heat consumption (qgrA)

kg/s
bar
°C
°C
kg/s
°C
MW
kJ/kWh

Swallowing capacity at steam turbine
(100% live steam pressure)

kg/s

Condition B: 75% Load Operation
Live steam flow
Live steam pressure at boiler outlet
Live steam temperature at boiler outlet
Reheat steam temperature at boiler outlet
Gross output (at generator termional)
Gross specific heat consumption (qgrA)
BPDB, Barapukuria Power Plant 250 MW
Section B0: General Specification
Guarantees, to be completed by the Bidder

kg/s
bar
°C
°C
MW
kJ/kWh
Minimum Requirements
Unit

Data

Condition C: 50% Load Operation
Live steam now

kg/s

Live steam pressure at boiler outlet
Live steam temperature at boiler outlet

bar
°C

Reheat steam temperature at boiler outlet

°C

Gross output (at generator termional)

MW

Gross specific heat consumption (qgrA)

kJ/kWh

Total auxiliary consumption including generator
excitation power and transformer losses at MCR
operation (Condition A)

MW

6 B0/FG-1
4

Total
auxiliary
consumption
(excluding
excitation power and transformer losses)
operation (Condition A)

generator
at MCR

List of detailed auxiliary consumers

MW

Drwg.No.

BPDB, Barapukuria Power Plant 250 MW

Minimum Requirements

Section B0: General Specification
Guarantees, to be completed by the Bidder
Steam turbine plant
Maximum increase in running speed of turbines in case of
sudden full load reduction
Drop in steam turbine condenser vacuum at closed air
suction I mbar/min valves at pure condensing operation
Boiler running time between inspections
Within this period, it shall be possible to continuously
operate the boiler at MCR with the guaranteed steam
conditions without the need to stop the steam generator for
cleaning on the flue gas side. Normal cleaning of the
surfaces has to be executed with the installed cleaning
devices at a maximum of 3 cycles in 24 hours (continuous
blowing is not permitted).

Unit

Data

%

8

mbar/min

less than 1.5

h

8,000

It is presumed that the boiler is operated in accordance with
the operating instruction.
The necessity for terminating the boiler running time will
arise if there is:




a rise in the correct flue gas temperature at the
regenerative air preheater outlet of greater than 20 K or
a rise in the pressure loss on the flue gas side up to the
regenerative air preheater outlet of greater than 20% or
the design temperature of the superheater or reheater
material at any location is exceeded.

If the guaranteed boiler running time of 8,000 h cannot be
fulfilled, improvements remedy of defects have to be
executed and after these the full running time test has to be
started again.
Emissions
At all loads and operating conditions of the steam generator
with coal" firing following emission limits shall not be
exceeded, measured In the chimney:


Nitrogenoxides (NOx) of the flue gases, calculated as N02
(stp, dry, 5% O2)
Carbonoxid (CO) of the flue gases (stp, dry, 5% O 2)

mg/m3
mg/m3

6 B0/FG-1
5

• content of solid particles in the flue gas (stp, dry, 5% O2)

mg/m3

leaving the EP
CO2 drop (dry) between combustion chamber and
regenerative air preheater outlet at MCR
BPDB, Barapukuria Power Plant 250 MW

%
Minimum Requirements

Section B0: General Specification
Guarantees

Unit

Data

h

12,000

• general

h

20,000

• special, easy changeable (wear plates)

h

8,000

• refractory

h

8,000

• general

h

16,000

•special, easy changeable

h

8,000

•load range 50 - 90%

%of
MCR/mi
n

±6

• load range 30 - 100%

%of
MCR/mi
n

±4

%MCR

35

-

1:5

Wear and tear parts
Coal mills
Pulverized coal operated parts

Ash transporting parts

Load changes

Start-up and backup firing
• capacity
• turn-down ratio

6 B0/FG-1
6

BPDB, Barapukuria Power Plant 250 MW

Minimum Requirements

Section B0: General Specification
Guarantees

Unit

Data

MCR of turbine generator

%

10

Specific heat consumption

%

10

Auxiliary consumption

%

10

Starting and loading time

%

30

Live steam and reheat steam temperature deviation

K

8

Effective vibration velocity

mm/s

2.5

Oxygen content in feed water or condensate

mg/l

0.02

Rejection
Further to the stipulations stated in other parts of
the
Tender
Documents
the
Owner/Owner's
Representative reserves the right to reject in the
following:
Should the deterioration of the guarantee values be
greater
than
the
following
values
then
the
Owner/Owner's Representative shall have the right
to reject the respective scope of this Section

or any other guarantee value is not met.

6 B0/FG-1
7

BPDB, Barapukuria Power Plant 250 MW

Bidder/Contractor

Section B0: General Specification
Design Data and Guarantees for I&C Equipment

Unit

Data

constant load

K

±4

• load variation

K

±10

bar

145

• constant load

bar

±1

• load variation

bar

±4

General guarantees for I&C equipment
With respect to the guarantees, acceptance tests and tolerances,
the appropriate IEC recommendations or the valid national
standards to be given by the Contractor will apply as far as they do
not contradict to this specification.
Closed loop control systems
All control loops shall be stable for all operating conditions and in
all load ranges, and shall have optimum performance in compliance with the present standards. Due to interconnections, the
control loops assigned to the main controlled variables shall not be
considered as separate units.
They shall be matched in such a way that optimum control of the
unit is accomplished in compliance with the requirements.
For closed loop control systems the quality of control shall be such
that for the load changes specified, not only shall control parameter
overshoot values not exceed the amount specified below but also
that all such overshoot values shall return to the set value in a
sinusoidal manner at a rate of not more than 35% in wave
amplitude for each successive half cycle, giving steady state
conditions after 3 cycles of overshoot.
The Contractor shall also demonstrate during the trial operation
period that the various control systems meet the specified
guarantees. The magnitude of the overshoots to be guaranteed is
specified for constant load and load variations in the following text.
Definition:
Load variation means change in fuel feed with a maximum rate of
change of 10% live-steam flow per minute. limited to 3 minutes within
the possible load range of the boiler.
Overshoots

a) Live-steam temperature:

b) Live-steam pressure:

6 B0/FG-1
8

Bidder/Contractor
BPDB, Barapukuria Power Plant 250 MW
Section B0: General Specification
Design Data and Guarantees for I&C Equipment
c) Reheat steam temperature:

Un
it

Data

• constant load

K

±4

• load variation

K

±10

d) Boiler drum level:
• constant load
• load variation

e) Boiler furnace pressure:
• constant load
• load variation

f) Combustion oxygen content:
• constant load
■ load variation

m
m
m
m
mb
ar
mb
ar
%
O2
%
O2

±25
± 50
±3
±8

±0.4
± 1.0

g) load variation Steam pressure and steam temperature reducing
station HP bypass control
• constant load

bar/
o
C

• load variation

bar/
o
C

± 3/ ± 10

dB
(A)

85

Under all operating conditions, the noise level of control valves
shall not exceed measured at one meter distance.

±1.5/±5

To make sure that the permissible noise level is under no
circumstances exceeded, the requirements in respect of the
pipeline and insulation design to be fulfilled by the piping an
insulation contractor shall be specified by the Contractor with the
tender.
Other control and monitoring systems
The Contractor shall guarantee that the equipment provided is
within the tolerances stated in the specification. The Contractor
shall also guarantee that the equipment carries out in a safe and
efficient manner the task for which it is provided.
The quoted values data shall be guaranteed.

Testing procedures
All components supplied shall be tested in accordance with the
requirements and the individual guarantees and the general
performance of the installation shall be demonstrated at the tests
during erection and the acceptance and performance tests.

6 B0/FG-1
9

BPDB, Barapukuria Power Plant 250 MW

Bidder/Contractor

Section B0: General Specification
Design Data and Guarantees for I&C Equipment
Acceptance tests serve to provide evidence of the
warranted
performance
the functions of individual equipment and/or
equipment
assemblies and also for
good functioning between control equip. and
controlled
system
Acceptance tests shall be performed for the closed loop
control
system only.
For all other parts and systems, successful and faultless
functioning during the time of completion, first start-up and
the
trial runs and random acceptance tests shall be taken as
an
acceptance test.
The Client or his representative will perform tests on
completion
in accordance with the requirements specified in the
contract,
e.g. checking of measuring circuit accuracy's, control
processes,
signal combinations, perfect operation of sequence or
logic
controls, etc.
Acceptance tests for closed loop control
How well the supplied control equipment and the
controlled
system work together under operating conditions will be
checked
during the control process.
The control process is the variation of the controlled
variable in
time under the influence of intentional (test) disturbances
and/or
operational disturbances .
The acceptance test is a comparison between the
warranted and
measured control process.
The acceptance test is successfully performed if the total
of
disturbance influences, including the test disturbance and
the
influences caused by the test disturbance in the system,
are

Unit

Data

under control to a degree whereby the warranties
concerning the
control quality are fulfilled.
As measurement tolerances, ±1% of the set values to be
warranted are permissible.
The acceptance test shall be repeated if, due to
extraordinary
disturbances in operation during the test, the control
process
does not correspond to the control process under normal
operating conditions.
BPDB, Barapukuria Power Plant 250 MW
Section BO: General Specification
Design Data and Guarantees for I&C Equipment

Bidder/Contractor

Unit

Data

If the main performance data are not fulfilled during the acceptance tests, the Contractor shall be obliged as a first measure
to improve the supplied control equipment by suitable control
Owner/Owner's Representativeing measures making full use
of all theoretical and equipment Owner/Owner's
Representativeing possibilities e.g. by
load dependent parameter variation
disturbance variable feed forward
further optimization efforts


modification of characteristics curve of control valves and
actuators etc.
For this purposes the Contractor is given the chance to
modify the equipment in a reasonable time specified by the
Client according to the system operation needs.
If, after final optimization, the quality of the closed loop control
does not meet the requirements the Contractor shall be
obliged to take the actual transient functions at the plant and to
compute the theoretical possible quality of the control loops
based on the actual data.
The Contractor of the equipment involved, the Client and/or
his representative reserve the right to participate in these
tests.
If the actual achieved control deviation does not exceed those
based on the theoretically calculated possible control quality,
the requirements shall be considered as fulfilled.
Should the plant fail to meet the above guarantees after due
account has been taken of the above specified tolerances, the
plant will be made available to the Contractor so as to allow
the Contractor to make good the plant by modifying or
replacing defective or wrongly designed parts.
If, even after remedial measures have been carried out, the
required guaranteed values are not achieved, then the
client shall be entitled to reject the complete plant or parts
thereof.

BPDB, Barapukuria Power Plant 250 MW
Section B0: General Specification
Guarantees Data- Water Storage and Treatment Systems
(to be completed by the Bidder)

Bidder/ Contractor
Unit

Data

Demineralization water plant
Net continues flow rate each line at design conditions
Net treated water volume per cycle each line
Cycle length (service time)
Regeneration time
Chemical consumption cation/anion per regeneration:
• HCI 100% each line
• NaOH 100% each line
Chemical consumption mixed bed per regeneration:
• HCI 100% each line
NaOH 100% each line
Quality of treated water:
• conductivity at 25°C (measured after cation
exchanger)
• total iron (Fe)
• total copper (Cu)
• silica (SiO2)
• sodium ((Na)

m3/h
m3
h
h
kg/cycle
kg/cycle
kg/cycle
kg/cycle

pS/cm

<0.01

mg/I
mg/I
mg/I
mg/I

<0.02
<0.003
<0.02
<0.01
Bidder/ Contractor

BPDB, Barapukuria Power Plant 250 MW
Section B0: General Specification
Time Schedule

Anticipated time schedule

• Time from Award of Contract to FOB (main
components)
• Time required for transportation
• Time required for erection and commissioning
• Provisional Taking Over

Days after
effective
Date

Date

B0/FZ-1

X
X
X
X
X
X
X
X
X
X
X
X
X
X
X

General Technical Requirements

0.6.1
0.6.2

General requirements
Standards and codes

0.6.3
Plant

Plant and equipment identification (e.g. Power

0.6.4
0.6.5
0.6.6
0.6.7
0.6.8
0.6.9
0.6.10
0.6.11
0.6.12
0.6.13
0.6.14
0.6.15
equipment
0.6.16
0.6.16.1
0.6.16.2

Coding System KKS)
Marking and labeling of crates and packages
Corrosion protection coaling and galvanizing
Vibration
Standardization of makes
Accessibility
Signs
Units of measurement
Ways, stairs, ladders, balustrades
Hazardous areas fire protection provisions
Maintenance isolation
Materials
Pre-service cleaning and protection of plant
Mechanical equipment
Pumps
Piping and accessories

0.6.16.2.1

Standards and general conditions

0.6. 16.2.2
0.6.16.2.3
0.6.16.2.4
0.6.16.2.5
0.6.16.2.6
0.6.16.2.7
0.6. 16.2.8
0.6.16.3
0.6.16.4
0.6.16.4.1
0.6.16.4.2

Material and construction standards
Bolts and nuts
Pipe supports and anchors
Cleaning at workshop
Cleaning at site
Wall boxes and collars
Expansion and flexibility
Piping design criteria
Welding and heat treatment
Responsibility
Required documents

0.6. I 6.4.3

Welding procedure qualification

0.6.16.4.4
0.6. 16.4.5

Personnel qualification
Welding process

0.6.16.4.6
0.6. 16.4.7

Pre-heating and heat treatment
Documentation

0.6.16.5
safety

Valves, steam traps, condensate drainers,
valves, control valves

Table of Contents
0

xxx

0.1
0.2
0.3
0.4
0.5
0.6

works
0.6.17.1
0.6.17.2
0.6.17.3
0.6.17.4

0.6.16.6
Insulation0.6.16.7
Vessels, tanks, heat exchanger
0.6.17
Electrical equipment and
Standards
Standard voltages
Climatic conditions
Inductive interferences

0.6.17.5
Color code system for
switchgear, for local switching
measurement-control-signaling cabinets
and for mimic
diagrams

0.6.17.6
equipment
0.6.17.7
0.6.17.8

Protection class for electrical operational
and control and monitoring equipment
Protective measures
Auxiliary equipment

0.6.17.9

Requirements for local cubicles and local
housings for
e.g. switchgear, control, measurement and
signaling
equipment

0.6.17.10
0.6.17.11
0.6.17 .12
0.6.17 .13
0.6.17. I 4
0.6.17.14.1
0.6.17 .14.2
0.6.17 .14.3
0.6.17.14.4
0.6.17.14.5

Local control points and level control cabinets
Terminal boxes and terminal cabinets
Explosion proof equipment
Keys and key cabinets
Electric motors
High voltage motors
Low voltage AC motors
Actuator drives
DC motors
Painting

0.6.17 .14.6
0.6.17.14.7
0.6.17 .14.8
0.6.17 .14.9
0.6.17 .15
0.6.18
0.6.18.1
0.6.18.2
0.6.18.3
0.6.18.4
0.6.18.5
0.6.18.6

Protection against explosion hazards
Frequency converters
Tests
Motor list
Labels
Instrumentation and control
Measuring units
Sizes of indicators, recorders, etc.
Protection and safety interlocks
Special local conditions
Tests
Field equipment

0.6.18.6.1
0.6.18.6.2
0.6.18.6.3
0.6.18.6.4
0.6. 18.6.5
0.6. 18.6.6
0.6. 18.6.7
0.6. 18.6.8
0.6. 18.6.9

Measuring systems/transmitters
Flow measurements
Temperature measurements
Pressure measurements
Analyses measurements
Level measurements
Electrical measurements
Position measurements
Contact devices

0.6.18.6.10
0.6.18.6.11
0.6.18.6. 12

Vibration measurements.
Control valves
Actuators

0.6.18.6.13.
0.6.18.7
0.6.18.8
0.6.18.9
0.6.18.10

Local instrumentation
Racks, junction boxes
Transmitter racks and piping
Programmable logic controller
Control cubicles

0.6 General Technical Requirements
0.6.1 General requirements
The following directions, information and technical requirements for
engineering, layout, erection, installation and testing shall be observed as far
are applicable for all equipment to be delivered. The requirements stated
Section of General Technical Requirements are valid for all sections
specification, except only where additional and/or special requirements are specified.

design,
as they
in this
of the

Any changes on the design of any part, of the Plant, which may become necessary
after signing of the Contract have to be submitted by the Contractor in writing to the
Owner/Owner's representative for approval, being sufficiently substantiated and
justified.
The Plant shall be brand new and clean, and designed, manufactured and arranged
so that it will have a functional design and a pleasant appearance. All parts of the
Plant shall be arranged in such a manner as to facilitate surveillance by the operator
and to ease maintenance, operation and control.
The parts of the Plant shall be designed and arranged so that they can be easily
inspected, cleaned, erected and dismantled without necessitating large scale
dismantling of other parts of the plant. They shall be designed, I1lClnufactured and
put into operation in accordance with the latest recognized rules of workmanship,
modern engineering practice and with good standards of prudence applicable to the
international electricity generation industry which would have been expected to
accomplish the desired result at the lowest reasonable cost consistent with reliability,
safety and expedition.
The regulations, standards and guidelines listed in the Specification as well as all
applicable laws and governmental decrees, regulations, orders, etc. shall be
observed in the design, calculation, manufacture, erection, installation, testing,
commissioning and start-up of all parts of the Plant.
The following
facilities:

shall

be

considered

in

the

design

and

engineering

of

the

Plant



All parts of the Plant shall be suitable in every respect for continuous operation at
maximum output as well as part loads and expected transient operating
conditions peculiar to the site and shall be able to safely withstand the stresses
arising from the operating conditions without any reduction in its planned life
which shall be at least equal to 200,000 operating hours.



The Contractor shall familiarize himself with the conditions on site and in the
country, especially with respect to transportation of heavy loads and flood.



Suitable and automatically acting protection and safety measures shall be
provided for automatic load reduction or shut down of equipment in case of
abnormal operating conditions.



Switch over to stand-by units shall be automatically, as far
continuous Plant operation without interruption of Plant operation.



In case of equipment and/or system shut down process conditioned drainage of

as required for

components (such as pipelines, tanks, etc.) shall be performed automatically or
manually from the control room.


Minor equipment which, in case of failure would cause a failure of a power
generation unit and/or the Plant is to be provided with a stand-by facility in order
to ensure further operation of the power generation unit or the Plant.



All live, moving and rotating parts shall be provided with appropriate effective
protection in order to avoid danger to the operating staff. All metal parts shall be
electrically grounded.



All equipment shall be designed to ensure start-up from any condition, i.e. from
cold, warm or hot condition without necessitating special or preparatory
measures.



Special attention shall be paid to interchangeability of plant components.



The project language shall be English.

0.6.2 Standards and codes
The work must be performed according to the most
standards, accident prevention regulations and legal regulations.

recent

relevant

codes,

All materials and equipment supplied and all work carried out as well as calculation
sheets, drawings, quality and Class of goods, methods of inspection, specific design
features of equipment and parts and acceptances of partial plants shall comply in
every respect with the following technical standards, codes and regulations .


Statutory safety regulations for equipment items (e.g. for noise preventions).




Accident prevention regulations of the Employer's liability insurance association,
Regulations and rules of the Factory and Shop Inspectorate,
recommendations, directives and rules, Steel-Iron-Material Specifications,
Material Specifications and Specification of Pressure Vessel Code.

Internationally recognized standards may apply for standards and regulations.

The Contractor shall propose the international standard chosen by himself.
If this standard once is approved, the Contractor has to follow up. No standard mix
will be all owed.
It is the Contractor's responsibility to provide sufficient evidence that any national or
other standard the Contractor proposes will ensure a high standard.
Before starting his works, the Contractor shall deliver those standards in English
language, which will be used on site to the Owner/Owner's representative and
the Engineer.

0.6.3 Plant and equipment identification (e.g. Power Plant Coding System KKS)
The Contractor shall apply a plant identification system showing the name and number
of each item of plant and its respective arrangement drawing number and add any
additional items necessary to fully identify the plant. The identification and numbering of
equipment, systems, items, etc. of supply, as well as of all documents and drawings
shall
be
in
accordance
with
the
IDENTlFICA
TION
system
(KraftwerksJiennzeichnungssystem = Power Plant Coding System PPCS) or equal. The
IDENTIFICATION system is available from
VGB-Kraftwerkstechnik GmbH,
VerIag technisch-wissenschaftlicher Schriften Klinkestrasse 27
- 31,45136 Essen, Germany.
The Contractor shall work with this or any equivalent system that the works me going on
smoothly.
There is to be only one description for anyone item of plant and this must be used
consistently for plant, electrical and instrumentation designations throughout.
The Contractor shall supply all labels, nameplates, instruction and warning plates
necessary for the identification and safe operation of the plant, and all inscriptions shall
be in the English/Bangla languages.
All labels, nameplates, instruction and warning plates shall be securely fixed to items of
plant and equipment with stainless steel rivets, plated self tapping screws or other
approved means. The use of adhesives will not be permitted.
Nameplates for plant and equipment identification and record purposes shall be
manufactured from stainless steel or aluminum with a mat or satin finish, and
engraved with black lettering of a size which is legible from the working position.
Warning plates shall be manufactured from stainless steel or aluminum engraved
red white lettering on a white background and sited in the position where they afford
maximum safety of personnel.
All equipment within panels and desks shall be individually identified by satin or mat
finish stainless steel or aluminum labels, or laminated plastic labels where
approved.
Each circuit breaker panel, electrical control panel, relay panel, etc. shall have a
circuit designation label on the front as well as on the rear panels engraved with
black lettering in
accordance with
the circuit
designation
system.
Circuit
designations must be precise and convey complete information. There should be no
doubt whatsoever for the operation as to which area of the plant a particular feeder
is supplying with power. Labels such as interconnector 1, feeder 2 are not
acceptable. Corridor type panels shall in addition have circuit designation labels
within the panels.
Pipe work systems shall be identified with a color identification systems in conformity
with the colors according to the chosen standards, with colors af the nameplates
and, if necessary by color bands and with identification numbering and plain
language. The direction of flow shall be shown.

Each valve shall be fitted with a stainless steel or aluminum name plate indicating
the valve service and reference number in accordance with the IDENTIFICATION
system.
Where possible valve nameplates shall be circular and fitted under the hand wheel
captive nut. They have to be of such a diameter that there is no danger for persons
operating the valve or that they do not prevent lock-off of this valve; on check valves
and small valves the Contractor may provide rectangular nameplates fitted to
brackets on the valve or attached to a wall or steelwork in a convenient position
adjacent to the valve.

0.6.4 Marking and labeling of crates and packages
Each crate or package is to contain a packing list in a waterproof envelope. All items
of material arc to be clearly marked for easy identification against the packing list.
All cases, packages, etc. are to be clearly marked on the outside to indicate the total
weight, where the weight is bearing and the correct position of the slings and arc to
bear all identification mark relating them to the appropriate shipping documents.
All stencil marks on the outside of cases are either to be made in waterproof material
or protected by shellac or varnish to prevent obliteration in transit.

0.6.5 Corrosion protection, coating and galvanizing
This specification shall be used for the corrosion protection of steel structures,
components, pipings and equipment in general which are installed in confined
areas (indoors) or outdoors.
Surface preparation, as well as protective coatings and coating systems are based
on this specification in order to assure that structural parts of different suppliers will
get a corrosion protection of similar and high quality .
Coating material shall only be supplied by manufacturers
experience and their products can be obtained internationally.

with

international

Regarding maintenance work (storage), application and supervision of coating work,
choice of coating suppliers should be minimized. At any rate, similar parts of
structures/components (such as structural steel, containers, piping, etc.) shall only
be coated with products of one individual manufacturer.
The manufacturer's materials and equipment used, the methods of application and
the quality of work shall at nil times be subject to the inspection and approval of the
Owner/Owner's representntive or his representative.
Codes and standards
Applicable standards are to be proposed for:



indication of pipe-lines according to flowing material
surface roughness



tight blasting agents
•corrosion protection, hot dip batch galvanizing of single parts, requirements and
testing
•corrosion protection of structural steel work through protective coatings and
topcoats
•preparation of steel substrates before application of paints and associated
products
•paints and varnishes - corrosion protection of steel structures by protective paint
systems
color card
•Swedish standard or equivalent for steel surface preparation steel structure
painting council.



Surface preparation and cleaning of surfaces in the shop
Prior to blasting, areas have to be cleaned from








oil
grease
paint residues
splatters
mill scale
welding splashes and
Welding slag.
Sharp edges have to be rounded off.
Contamination caused by salts, acids and alkali solutions shall be eliminated by
rinsing with water up to a pH value of 6-8.
The preparation of substrates
according to proposed standards.

shall

be

carried

out

on

the

basis

of

the

specifications

After blasting, an anchor profile of 25 - 50 shall be achieved. Blasted surfaces have
to be provided with a prime coat of the considered coating system immediately after
blasting.
Cleaning to be performed on site
Steel work protected by shop primer after arrival on site must be c1eancd of salt,
sand, oil, etc. before the first coat of paint is applied on site. Shop primer damaged
during transport must be rectified by blast-cleaning and coating before application of
the site coats.
Wood shall not be used.
If a protective
before painting.

coating

of

concrete

is

required,

concrete

shall

be

allowed

to

cure

Transport and erection damages, as well as damages which result out of additional
welding have to be repaired as soon as possible. The damaged areas have to be
derusted with rotating or steel brushes, abrasive wheels, abrasive blasting according
to the chosen standards.

Cleaning of prime and intermediate coats (if required)
To prevent contamination by mineral oil products, areas with prime and intermediate
coat have to be treated with suitable cleaning agent. Cleaning has to be done free of
residues, e.g. with alkaline detergents and thorough washing done with fresh water.
Rusty spots have to be removed according to required purity. Metallic areas which
are provided with temporary corrosion protection have to be cleaned. No oxidation
products shall remain on the surface. Furthermore it has to be taken care that on hot
components no destructive nor reaction products will be released when heating
which could injure insulation.
Application procedure
When
using
the
provided
coating
material,
strict
adherence
to
all
application
instructions given in product data of coating. manufacturer is necessary. To obtain
the maximum performance, technical data as well as application instructions for the
individual coating material have to be strictly followed.
For a multi-layer coating system each layer
order to clearly identify number of coats applied.

has

to

have

a

different

color

shade

in

The last finish coat has to be applied in the specified color shade, to be agreed by
the Owner/Owner's representative.
The interval between applying the different coats has to follow according to supplier's
precautions. Each layer has to be cleaned and released from spray dust before the
next layer will be applied. Prior to applying a further layer, the last one has to be
repaired. All coatings have to be applied without retarding.
Following application procedures are allowed:


prime coats by airless spray
areas like disconnections, angles, comers, etc. which are difficult to be reached
can be applied by brush or roller




repair of prime coat by brush
finish coats

at works
by airless spray, roller or brush

at site
by roller or brush or airless spray.
When applying coating systems by roller, rollers have to be of kind and quality
which make an appropriate application possible.
Control areas in accordance with the coating supplier's instructions have to be
applied. For this procedure, a schedule for control areas has to be prepared by the
Contractor and coating supplier which corresponds with the requirements of the
warranty agreement.
Number and performance of the control areas have
the chosen standards and have to be documented in writing.

to

be

done

in

accordance

with

No application may take place neither when the relative humidity will not be within
the given limit nor in case of fog, dust, rain, snow or hail or when it can be assumedthat such conditions
of poor weather within 2 hours after application can arise.
Temperature of the coated parts has always to be above 5°C and 3 K above dew
point.
All specified dry film thicknesses (DFT) are minimum thicknesses.
Welding seams mounted at site have to be taped with an adhesive tape of about 30-50
mm after surface preparation (blasting or manual derusting) and prior to application in
the manufacturing plant and to be coated with stripping coat.
Chequered plates, nap plates, etc. have not to be covered with adhesive tape, but have
to be coated with stripping coat in a dry film thickness of at least 150 ^m.
Edging lines on steel structure have to be taped prior to application and after blasting
in sufficient width or have to be protected with varnish before application. Thickness
of prime coat may be 50 ^m max.
During repairing works at site on shop-primed structures, it is important that different
coats will have different colour shades. Number of layers has to be the same as the
original coating system to be used.
Application of temporary primer on structures which have to be insulated has to be in
accordance
with
a
sufficient
corrosion
protection
for
the
period
of
storage
respectively erection time.
Galvanizing
Galvanizing work shall conform in all respects to the chosen standards and shall be
performed by the hot dip process unless otherwise specified.
It is essential that details of steel members and assemblies which arc to be hot-dip
galvanized should be designed to suit the requirements of the process. They should
be in accordance with the chosen standards.
Vent holes and drain holes shall be provided to avoid high internal pressures and air
locks during immersion and to ensure that molten zinc is not retained in pockets
during withdrawal.
Careful cleaning of welds is necessary before welded assemblies are dipped.
All defects of the steel surface including cracks, surface laminations, laps and folds
shall be removed in accordance with BS 4360. All drilling, cutting, welding, forming
and final fabrication of unit members and assemblies shall be completed, where
feasible, before the structures are galvanized.
The minimum average coating weight shall be as specified in the chosen standards.
Structural steel items shall be first grit-blasted (Sa 2 1/2) or pickled in a bath, and the
minimum average coating weight on steel sections 5 mm thick and over shall be
2

900 g/m , on steel sections 2 - 5 mm thick 600 g/m .

2

Galvanized contact surfaces to be joined by high-tensile friction-grip bolts shall be
roughened before assembly so that the required slip factor is achieved. Care shallbe taken to ensure
that the roughening is confined to the area of the mating faces.
Protected slings must be used for off-loading and erection. Galvanized work which is to
be stored at the works or on site shall be stacked so as to provide adequate ventilation
of all surfaces to avoid wet storage staining (white rust).
Small areas of the galvanized coating damaged in any way shall be restored by:


cleaning the area of any weld slag and thorough wire brushing to give a clean surface
•the application of two coats of zinc-rich paint, or the application of a low melting point
zinc alloy repair rod or powder to the damaged area, which is heated to 300°C.
Connections between galvanized surfaces and
surfaces shall be protected by suitable tape wrapping

copper,

copper

alloy

or

aluminum

oating Systems

Surface location

Structural steel works, piping,

Temp.oC

Surface
preparation

up to 120

SA 2.5

vessels, tanks
INDOOR

Structural steel works, piping,

up to 120

SA 2.5

vessels, tanks
OUTDOOR

Coating
systems

No.of
coats

Generic type

Dry film thickness
(DFT) per coat
|jm

Primer

1

Zinc-Epoxy

80

Finish

1

Epoxy High Solid

80

Primer

1

Zinc-Epoxy

80

1-2

Epoxy High Solid

1

2-Comp.Polyurethane

Intermediate
Finish

T

160

16

50

50

29
Piping, tanks, etc.
INDOOR and OUTDOOR,
Insulated

up to 120

SA 2.5

Primer

1

Zinc-Epoxy

50

up to 120

SA2.5

Primer

1

Zinc-Epoxy

80

Pumps, motors, other equipment
OUTDOOR
Intermediate

1

Epoxy High Solid

Finish

1

2-Comp.Polyurethane

110

11

50

50

24
1
Primer
Finish
INDOOR

2

Zinc-Epoxy
Epoxy High Solid

oo

Pumps, motors, other equipment

SA 2.5

00 LO

up to 120

80

10

18

oating Systems

Surface location

Piping, reactors

Temp.oC

> 120

Surface
preparation
SA 2.5

Coating
systems
Primer

No.of
coats
1

Generic type

Zinc Ethysilicate

Dry film thickness
(DFT) per coat
pm
75

OUTDOOR
Insulated
SA 2.5

Stacks
OUTDOOR

< 120

Steel surfaces

<200
200 - 450

1
Primer

Zinc Ethysilicate

75

2
SA 2.5

Finish
Primer

I

Silicone Acrylic
Zinc Ethysilicate

50
75

Finish

2

Silicone Aluminium

25

When Finish
Coat is
required, such
as sea climate
with chloride
exposure

I

Epoxy High Solid ■

125

Un insulated

Galvanized surfaces

Steel surfaces permanently in
contact with water

up to 120

Medium
temp.oC
up to 60

Mechanical
cleaning from
contaminants
and zinc salts
by means of
washing or
steam or
sweep- jetting
blasting with
fme sand

Prime and
1
Finish
Glassflake reinforced
Coat in
High Solid Epoxy.
Additional 1 x Finish Coat 2-Comp. Polyurethane, 50 pm, when exposed to UV and colour One
retention is required or when exposed to weathering.
SA 2.5

500

T

0.6.6 Vibration
Unless otherwise stated or agreed by the Owner/Owner's
Owner/Owner's representative each rotating machine has
requirements for vibration magnitude (criterion I) designation
by ISO Specification 10816 or equivalent for the respective
the vibration magnitude is greater than stipulated as "zone
representative has the right to reject the concerned equipment. .

representative or ; the
to comply with the
as "zone A" stipulated
group of machinery. If
B", the Owner/Owner's

0.6.7 Standardization of makes
The works shall be designed to facilitate inspection, cleaning, maintenance and
repair. Continuity of supply is a prime concern. The design shall incorporate every
reasonable precaution and provision for the safety of all those concerned in the
operation and maintenance of the works. The plant shall be designed to operate
satisfactorily under all variations of load, pressure, and temperature.
Corresponding parts
wherever possible.

throughout shall

be

made

to

gauge

and

be

interchangeable

All equipment performing similar functions shall be of the same type and
manufacture, to limit the stock of spare parts required and maintains uniformity of
plant and equipment to be installed.

0.6.8 Accessibility
The Contractor shall supply and erect sufficiently large safe platforms, galleries,
stairways and access ways necessary for providing safe and easy access to all the
plant items for operation and maintenance. The Contractor shall ensure that the
whole of the access ways is of W1iform design and pattern throughout the works.
Ladders are only to be provided as an extra means of escape. No dead ends are
allowed, especially where the escape way may be blocked by fire/steam, etc.
The design of all stairways, access ways etc. shall conform to the requirements of
Section 0.6.11.

0.6.9 Signs
General
Safety colors, safety symbols and safety signs must
geometrical form, color and meaning with the chosen standards.
Signs for plant identification during the
Owner/Owner's Representative approval.

erection

The signs should be of a material which
durability for the conditions prevailing on site.

is

comply

period

are

weather-resistant

in

construction,

subject

and

of

to

the

sufficient

Mounting and installation
The positions for the signs must be chosen so that they are within the field of vision
of the persons to whom they apply. The signs should be permanently attached.

89

Temporarily dangerous areas (e.g. construction sites, assembly areas) may also be
marked by movable signs. The safety signs must be mounted or installed in such a
manner that there is no possibility of misunderstanding.

Information signs
Information signs should supply the necessary information to acquaint personnel
with the physical arrangement and structure of site, buildings and equipment, e.g.
floor numbers, load-carrying capacities including marking of floor areas, working
loads of cranes, lifting gear and lifts, room identification, etc. The routing of
underground pipes and- cables is to be indicated by substantial marker blocks
showing the relevant identification numbers.
In the choice of information signs in situations not covered by the chosen standards
the possibility of using pictograms should be considered. Pictograms are particularly
suitable for the identification of rooms, areas and buildings in the non-technical areas
of the plant, sanitary and amenities buildings, etc.

Emergency signs
In the event of accidents, all necessary information should be available immediately
to those affected. Thus, a sufficient number of signs of appropriate size should be
installed, e.g. escape routes (including marking of floor areas), emergency exits, fire
alarms, fire extinguishers, instructions for special fire-extinguishing agents, warnings
against fire-extinguishing agents (C02), first aid equipment, first aid points, accident
reporting points, telephones, etc.

Mandatory signs
Signs indicating obligatory actions must be provided installed wherever certain action
is necessary, e.g. do not obstruct the entrance; keep right, etc.
Signs should also indicate when the wearing of protective clothing and equipment is
necessary and obligatory, e.g., protective goggles, protective clothing, helmets, head
guards, breathing equipment, ear muffs, etc.

Warning signs
Warning signs should refer to the existence or possible existence of danger, e.g.,
flammable substances, explosive substances, corrosive or noxious substances,
suspended loads, general danger, width height restriction, steps, risk of trapping,
slipping, falling, etc.
In addition to warning signs, appropriate black-yellow ~trip markings should also be
used where necessary.

0.6.10 Units of measurement
The Contract shall be conducted in the Systems International Units (SI) system of
units in accordance with the provisions of ISO 31 and ISO 1000.
In all correspondence, technical schedules, drawings and instrument scales, the
following units shall be used:

90

Quantity

Name of Unit

Length

Millimeter

Symbol
mm

Mass

Kilogram

kg

Time

Second

s

Temperature

Degree Celsius

°C

Temperature Difference

Kelvin

K

Electric Current

Ampere

A

Luminous Intensity

Candela

cd

Area

Square meter

m2

Volume

Cubic meter

m3

Liter

I

Force

Newton

N

Pressure (absolute)

Bar

bar

Kilopascal

kPa

Pressure below 1 bar

Millibar

mbar

Stress

Newton per square millimeter

N/mm

Velocity

Meter per second

mls

Rotational speed

Revolutions per minute

rpm
3

Flow

Cubic meter per day

m /d

Cubic meter per hour

m/h

Kilogram per hour

kg/h

Liter per second

L/s

metric ton per hour

t/h

For gaseous substance: standard Nm /h
cubic meter per hour (referred to
O°C and 1013 mbar)
Density

Kilogram per cubic meter

kg/m

Kilogram per standard cubic

Kg/Nm

meter
Torque, moment of force
2

Momcnt of inertia (mr )

Newton meter

Nm
kgm2

Kilogram square meter

Work, energy or heat

Joule

J

Heat capacity, entropy

Joule per Kelvin

J/K

Calorific value

Joule per cubic meter

J/m3

Joule per gram

J/g

Power, radiant flux

Watt

W

Heat release rate

Watt per square meter

W/m2

Thermal conductivity

Watt per meter Kelvin

W/mK

Dynamic viscosity
Quantity

Newton second per square meter Ns/m2
Name of Unit

Sym

91

Kinematics' viscosity

Meter squared per second

m2/
s
N/m

Surface tension

Newton per meter

Concentration

Parts per million

Electrical conductivity
Frequency

Micro Siemens per meter at 25°C
Hertz

ppm
^S/
m
Hz

Electric charge

Coulomb

C

Electric potential

Volt

V

Electric field strength
Electric capacitance

Volt per meter
Farad

Vim
F

Electric resistance

Ohm

n

Conductance

Siemens

S

Magnetic flux

Weber

Wb

Magnetic flux density

Tesla

T

Magnetic field strength

Ampere per meter

A/m

Luminous flux

Lumen

lm

Illuminance

Lux

Ix

Thermal resistivity

Kelvin meter per Watt

Energy

Kilowatt hour

Km/W
kWh

For the thermodynamic properties of steam and water the latest edition of the
"VDI- Wasserdampftafeln" (= Water Steam Tabular) shall be used which is based
on the formulations published by the International Formulation Committee (IFC)
under the title "The 1967 IFC Formulation, for Industrial Use".

0.6.11 Ways, stairs, ladders, balustrades
The Contractor shall supply all platforms, galleries and stairways necessary for
providing safe and proper access to the plant for operation and efficient
maintenance. The Contractor shall ensure that the type of flooring, stair treads and
handrails conform to a uniform pattern throughout the whole Project.
The loads for the design of platforms, galleries etc. shall be in accordance with the
section 'Design Loads' of the special civil part of these specifications.
All platforms, galleries, stairways and hand railing shall be of galvanized
unless otherwise specified.

,i

steel

All aspects of platforms, stairways, ladders and other access ways shall comply
with the requirements of applicable 'standards.

0.6.12 Hazardous areas. fire protection
provisions
Hazardous areas
The Contractor shall take full account of any special requirements concerning the

92

nature, handling and storage of all fuel oils, gases and chemicals etc., and provide
plant, equipment, buildings and other services accordingly, including all facilities to
ensure the safety of the operating and maintenance personnel.
The Contractor shall provide drawings to define all the hazardous zones taking
account of all sources of hazards under normal and abnormal operating conditions,
(regardless
of
whether
or
not
these
areas
are
specifically
listed
in
the
specification).The
zoning
philosophy
shall
be
subject
to
the
approval
of
the
Owner/Owner's representative.
In particular, equipment directly concerned with plant which may give rise to a
hazardous situation shall be designed to requirements with electrical connection
safety barriers or intrinsically safe equipment. Where required by the Engineer,
certification shall be provided to confirm the suitability of the equipment and
devices.
The
Contractor
shall
be
responsible
for
ensuring
that
all
electrical
equipment
installed in any hazardous zone is designed and tested to suit the relevant zone
classification and shall be to the approval of the Employer. Cables shall not be laid
in trenches etc with fuel pipe work.
Fire protection provisions
Unless otherwise
following
design
requirements:

specified or agreed with the Owner/Owner's Representative, the
principles
should
be
observed
as
minimum
fire
prevention



Pipeline insulation and the
be of non-combustible material.

in-fills

of



All pipelines or vessels with internal temperatures of more than 180°C shall be
so arranged as to avoid any contact with flammable liquids if fuel or lube oil
lines should leak. Sufficient physical separation shall be ensured.



Particular care should be taken to eliminate any risk of hot pipeline insulating
material becoming impregnated with flammable liquids in the case of fuel or
lube oil line leakage. The insulation is to be covered in its entirety, with an oil
resistant sheet, over which the cladding is to be fitted.



Cable and pipeline ducts must be so arranged and sealed as to avoid all risk of
flooding with fuel oil, lube oil or any other flammable liquid. In addition to
sealing the cable and pipeline ducts, the cable basements must be completely
scaled against leakage from above as well, in order to preclude the ingress of
lube oil or other flammable liquids.



Covered floor ducts must be easily accessible for inspection and cleaning.



All parts of plant and equipment are to be arranged so that no corners or pits
that would be difficult to inspect and clean and in which flammable matter could
collect are formed.



Fuel preheating temperatures
below the fuel flash point.



Lubricating
connected
points.

should

cable

be

and

limited

pipeline

to

oil lines in the turbine-generator lube
with compression-type joints but rather

a

wall

margin

penetrations

of

oil system arc
with welded or

93

at

are

least

to

10K

not to be
screwed-type



Non-combustible materials which do not release noxious or toxic fumes must
be used for wall and ceiling paneling, for floor covering, and for cubicles and
cabinets.



Corners likely to collect dust respectively-coal powder shall be prevented.

0.6.13 Maintenance isolation
All major equipment shall be arranged to facilitate safe isolation frol11 all
hazards for maintenance purposes. In addition all valves must be capable of
being locked either in the open or closed position by means of a chain and
padlock.
Non return valves are not acceptable as a means of isolation.

0.6.14 Materials
All materials shall be brand new and of the best quality for use in the conditions
and the variations in temperature and pressure that will be encountered in
service without undue distortion or deterioration or the setting up of undue
strains in any part that might affect the efficiency and reliability of the plant.
All materials shall correspond either to the approved standards and the
respective code number or to exact analysis data, and full information
concerning properties and applied heat, chemical and mechanical treatment
shall be submitted for Owner/Owner's Representant's spot check.
Special attention must be paid to eliminating the possibility of corrosion
resulting from galvanic effects. Design, selection of materials and all methods
of erection shall be such as to keep these effects to a minimum. Materials
complying with codes and standards listed below shall be used for the design
and construction work.
Unless the materials meet these codes and standards, they shall be subject to
the Owner/Owner's representative's spot check.
Materials and standards

(A)

a.

Structural steel

Standards chosen by the Bidder

(B)

b.
c.
a.

Structural steel tubes
Crane rail
High strength friction grip bolts
(H.S.F.G. bolt)

Standards chosen by the Bidder
Standards chosen by the Bidder
Standards chosen by the Bidder

(C)

b.
Torque shearing bolt
c.
Ordinary bolt
Electrodes for arc welding

Standards chosen by the Bidder

(D)

Ordinary Portland cement

Standards chosen by the Bidder

(F)

Reinforcing bars

Standards chosen by the Bidder

0.6.15 Pre-service cleaning and protection of plant equipment
This clause covers mechanical and pre-service cleaning and protection of the
plant items and equipment at the Manufacturer's workshop and at site that are
not subsequently to be painted.
Cleaning of fabricated component items shall be carried out after fabrication and
final heat treatment or welding at manufacturers' works or at site, as appropriate.
In the event of the surfaces not being cleaned to the Employer's or Engineer's
satisfaction, such parts of the cleaning procedures or agreed alternatives as are
deemed necessary to overcome the deficiencies shall be carried out at the
Contractor's sole expense.
Mechanical cleaning as opposed to alternative chemical cleaning is the preferred
method for workshop cleaning except where this. is precluded by design or
access c0!lsiderations.
Machined surfaces shall be protected during the cleaning operations. For
recleaning small areas, hand cleaning by wire brushing may be permitted. Wire
brushes used on austenitic materials shall have austenitic steel bristles.
Austenitic stainless steels, copper and aluminum alloys, cast iron, bimetallic and
metallic/plastic items, and components fabricated by spot welding or riveting shall
not be chemically cleaned. All weld areas shall be suitably stress-relieved before
chemical cleaning
At an appropriate time, the Contractor shall submit
work necessary to carry out the pre-service cleaning
works to be carried out on the pipelines, heaters,
etc. to connect the temporary pipe work with the
cleaned.

drawings of temporary pipe
simultaneously with a list of
feed water I tanks, vessels
parts of equipment to be

Further, the Contractor shall submit at the. same time the basic draft of the
cleaning procedure and of the treatment of wastes.
Not less than six months prior to the commencement of any site cleaning, the
Contractor has to submit programs covering all procedures, lists of chemicals,
calculations which quote the velocities, temperatures handpipework forces and
movements imposed during site cleaning.
All necessary equipment, provisions, chemicals etc. are to be provided by the
Contractor.
All tests, analyses, etc. as required arc to be performed by the Contractor.
Besides this, the Contractor shall take over all responsibility for the treatment and
disposal of wastes according to the local law and to the satisfaction of the
Owner/Owner's representative.
The date at which cleaning of plant equipment will be carried out at site shall be
notified to the Owner/Owner's representative at least 20 days in advance.
The Contractor shall take all necessary precautions to ensure that the internal
surf.1ces of all plant are kept clean and free from injurious matter during erection.

When all plant has been erected and lagged or at such other time as may be
agreed
with
the
Owner/Owner's
representative
for
sub-assemblies,
the
installation shall undergo a procedure for site cleaning proposed by the
Contractor and subject to the approval of the Employer.

0.6.16 Mechanical equipment
0.6.16.1 Pumps
General
All pumps shall be designed for continuous operation unless otherwise specified.
Pumps shall be installed in positions convenient for operation and servicing.
Where multiple pump installations are required, each pump and its associated
equipment shall be arranged in such a manner as to permit easy access for
operation, maintenance and pump removal without interrupting plant operation.
Pumps installed for parallel operation or as stand-by sets are to be of identical
design, i.e. interchangeable.
Lifting lugs and eyes and other special tackle shall be provided as necessary to
permit easy handling of the pump and its components.
General design and construction
All pumps shall be designed to withstand a test pressure of 1.5 times the
maximum possible pump shutoff pressure under maximum suction pressure
conditions. If a pump can operate at sub-atmospheric suction conditions, the
entire pump shall be designed for full vacuum.
All pump shafts shall be of ample size to transmit the maximum possible output
from the prime mover. The pump shaft and coupling are to be so dimensioned
that the maximum permissible torque of the shaft is higher than the maximum
transmissible torque of the coupling. Directly coupled pumps shall be used
preferably.
Renewable wear rings
economically justified.

shall

be

fitted

to

the

casing

and

impeller

where

All pumps and accessories in contact with the pumped fluid shall be constructed
of materials specifically designed for the conditions and nature of the pumped
fluid, and be resistant to erosion and corrosion.
Product water flushing lines are to be supplied for each pump handling seawater
to avoid corrosion if the pump is out of operation for extended periods.
The pump glands or mechanical seals shall be so arranged that repackaging or
fitting of replacement seals can be carried out with the minimum of disruption to
plant operation. In case of operating under vacuum conditions liquid sealing is to
be provided.
The pump casing shall preferably be split for ease of maintenance and be

designed such that the impeller and shaft are capable of being withdrawn from
the casing without disturbing any of the main paperwork. and valves carrying the
pumped fluid. In general, all horizontal pumps with draw-outrotors are to be fitted
with
a
coupling
to
facilitate
disassembly
without
removing
the
motor.
Pull-out
design of the shaft shall be applied to vertical wet pit and dry pit pumps as well.
Each .horizontal pump shall be mounted with its drive on a common base plate of
rigid construction. Vertical pumps are to be provided with foundation frames. In
case of submersible pumps suitable frames shall be provided in the pump sump.
It shall however be possible love these pumps without entering the sump.
Pumps must be carefully
available under all operating
employed. The NPSH values
conditions -lowest atmospheric
of the pump, and highest
margin of normally greater
provided.

set to ensure that the net positive suction head
conditions will be adequate for the type of pump
are to be referred to the least favorable operating
pressure, lowest level of water <W the suction side
temperature of the pumped fluid. An adequate safety
than 1 m to the max. NPSI-1 required shall be

Pumps shall operate smoothly throughout the speed range up to their operating
speeds. The first coupled critical speed must be at least 20% higher than the
maximum
operating
speed.
The
determination
of
the
shaft
diameter
and
the
distance
between
two
consecutive
bearings
must
include
a
sufficiently
large
safety margin to satisfy this condition.
Where necessary,
throughput.

the

pumps

are

to

be

fitted

with

devices

to

ensure

a

minimum

Bearings
For large pumps the bearings shall be of automatic oil lubricated sleeve type,
unless otherwise specified. Bearings on vertical shaft pumps shall be so spaced
to prevent shaft whipping or vibration under any mode of operation.
Bearings housings on horizontal shaft pumps shall be designed to enable the
bearings to be replaced without removing the pump or motor from its mounting.
Bearing housings on horizontal shaft pumps shall be effectively protected against
the ingress of water, pumped fluid and dust by suitable nonferrous deflectors.
All bearing oil wells shall be fitted with visual oil
lubricated bearings shall be equipped with constant level oilers.

level

indicators.

Non

they

be

pressure-oil

Pumps characteristics
When several pumps arc
unrestricted parallel operation.

installed

for

the

same

service,

shall

suitable

The pump flow/head characteristics shall be such that within the operation
the head will continuously increase with decreasing flow, maximum head
off head) being at least 10% higher than the duty point head.

for

range
(shut

Unless otherwise specified all pumps shall be capable of operating at 110% of
the rated capacity at the rated delivery head. Maximum size impellers shall not
be quoted for. By installation of a new impeller a head increase of 5% minimum
shall be possible. The performance of the drive motor is to be determined
according to the above mentioned technical requirements and to the
requirements as specified in the electrical part.

Fittings
All pumps shall be installed with isolating valves, a non-return valve and suction
and discharge pressure gauges unless otherwise stated. Accessible couplings
shall be supplied with removable type guards.

Coupling halves shall be machine matched to ensure accurate alignment.
Couplings as well as gears must have a rated capacity of at least 120% of the
maximal potential power transmission requirement.
All positive displacement pumps shall be fitted
capable of passing the maximum pump delivery flow.

with

a

discharge

relief

valve

Venting valves shall be fitted to all pumps at suitable points on the pump casing
unless the pump is self-venting, due to the arrangement of the suction and
discharge nozzles. Drainage facilities shall be provided on the pump casing or
adjacent pipe work to facilitate the dismantling of pumps.
All pumps other than submersible pumps shall have temporary strainers fitted in
the suction pipe work during all initial running and commissioning phases.
Permanent strainers shall be provided where specified.

0.6.16.2 Piping and accessories
As far as arrangement and number of valves for drains and vents, etc., are
concerned, the stipulation of this article define the minimum requirements.
The intent of this chapter is to describe the general technical requirements and
essential particulars of pipes, valves, fittings, expansion joints, insulation as well
as the complete power piping system furnished, fabricated, shop tested,
delivered, completely erected land installed, clean inside and outside, in first
class condition throughout, hydrostatically field-tested and demonstrated to be in
a condition to operate commercially and continuously in a manner acceptable to
the Owner/Owner/Owner's representative up to maximum operating conditions.

0.6.16.2 Piping and accessories
The intent of this chapter is to describe the general technical requirements and
essential particulars of pipes, valves, fittings, expansion joints, insulation as well
as the complete power piping system furnished, fabricated, shop tested,
delivered, completely erected land installed, clean inside and outside, in first
class condition throughout, hydrostatically field-tested and demonstrated to be in
a condition to operate commercially and continuously in a manner acceptable to
the Owner/Owner/Owner's representative up to maximum operating conditions.
As far as arrangement and number of valves for drains and vents, etc., are
concerned, the stipulation of this article defines the minimum requirements.

0.6.16.2.1Standards and general conditions
Piping and valves shall comply with currently approved applicable codes,
specifications and standards (latest revisions), such as DIN, American standards
(A.S.A., ASTM, ASME, A WW A), Japanese standards and shall conform with
the Contract specification.
All piping materials, bypasses, open blows, welding joints, flanges, bolting
materials, gaskets, piping supports, turn buckle red hangers, spring hangers,
guides, sway braces, vibration dampers, trays, brackets, anchors, rollers,
expansion bends, operating platforms and supports of all types as well as
miscellaneous structural steel and other items required to support the piping in a
proper manner, shall be included in all piping systems.

The Contractor shall include all incidental components
complete installation such as vents, drain lines, drip llines, etc.

necessary

for

a

Pockets in pipelines shall be avoided wherever possible and all lines are to be
provided with fittings, valves and/or traps arranged in such a way that the pipes
may be completely drained when desired.
Each mechanical component requires its identification coding number.

0.6.16.2.2 Material and construction standards
Welding wires and electrodes material for welded connection of pipe systems
shall be according to relevant standards or codes of the appertaining
piping system of the recommendation of the weld-material supplier. Adequate
information documents shall be sent to the Owner/Owner's Representative.
All valves. expansion joints, thermometer nozzle, supports and associated
equipment and instruments shall be supplied and installed by the Contractor in
a manner acceptable to the Owner/Owner's Representative .
For all piping systems, separate list of pipes and list of valves. shall be
submitted by the Contractor.
The Owner requires entirely and continuously-welded connections for all high
pressure temperature service including welding' of pipes to the valves or other
equipment. Other piping systems shall comprise all welded connections or
bolting of pipe to the valves or equipment. The use of odd or short pieces of
pipe in making up long runs is prohibited.
All pipe bends shall be made preferably to radii not less than five times nominal
pipe diameter unless otherwise specified; they shall be true to angle and radius
and maintain a true circular cross-section of the pipe without buckling or undue
stretching of the pipe wall.
The Contractor shall machine completely all welded ends on piping, bends and
fittings to make all welds sophisticated both in shop and field. Welding joint
design shall avoid all sharp comers.

0.6.16.2.3 Expansion and flexibility
Piping systems shall be calculated, supported, guided and anchored in such a
way as to preclude excessive thrust or stress due to the combination of leading
from internal pressure, thermal expansion and weight. The Contractor shall be
responsible for computing expanding movements and combined stress on and
weights of all major pipelines and for providing suitable supports and restraints
to assure compliance with the latest rules of the available standards. Reactions
at equipment connections shall be within the limits specified by the
manufacturers respective equipment.

0.6.16.2.4 Pipe supports and anchors
Pipe supports and anchors shall generally be situated at those points in the
building where provisions has been made to sustain the loads imposed. The
cutting of floor or roof beams of the reinforcement in slabs shall not be
permitted. Piping attached to a plant item shall be supported in such a way
that the weight of the piping is not carried by and no stress is exerted on the
plant item.
Since certain parts of the building may be constructed in reinforced concrete,
the position of all pipe supports and anchors, and -the loads imposed by
them, shall be determined sufficiently early to allow appropriate provisions to
be made.
All pipe supports and anchors shall be preferably located at the main grid
lines of the structures and buildings. Where pipe supports and anchors are
required elsewhere, all the secondary beams to direct the load to the main
beams and connecting pipes shall be provided by the Contractor.
Only minor loads shall be permitted to hang to the concrete slabs and subject
to
the
approval
or
Owner/Owner's
Representative.
The
supporting
arrangements - inapplicable - shall be capable of supporting the weight or the
piping systems when full of water during, chemical cleaning or hydraulic
testing. The number and position of pipe supports shall be such that the
piping may be free to move, and that lateral loading on the piping system
under working conditions may be minimized.
Constant load supports shall be fitted where considered necessary.
All supports for high pressure steam and other pipes subjected to high
temperature conditions shall be fastened onto the pipe under consideration of
the operating conditions of the pipe supported. The material influenced by the
temperature conditions shall be of nearly the same quality as the related
pipe.
Supporting straps around flanges of pipes or valves or around welded joints
will not be accepted. Anchors shall be attached to pipes by approved means.
Main support shall be shop-fabricated and shall be positioned near the joints
and valves wherever possible before the erection of the piping takes places,
and shall be clamped onto the pipe by bolting wherever poss1ble.

Terminal points between pipe work supplied by different manufacturers shall
be carried out as "fixed points" in such a way that at the point of connection,the pipe
shall be fixed in a constant position if not otherwise instructed by the
Engineer. The Contractor is responsible for meeting all the requirements for
pipe connections established by the manufacturers of the turbine, the pumps
and other relevant equipment.

0.6.16.2.5 Cleaning at workshop
On completion of all bending, flanging and other operations on pipes
necessitating application of heat, with the exception of welding on site, the
pipes shall be completely immersed in a pickling solution for a period not less
than two hours, to remove all grit and mill scale. An inhibitor shall be used in
the pickling solution. Removal of internal scale by sandblasting is not permitted.
Alternative procedures (shot blasting), according to the
Contractor may be accepted, subject to approval by the Engineer.

practice

of

the

After drying, inspection and conservation, wooden plugs, metal or plastic caps
shall be securely fitted to the ends of each pipe to prevent the ingress of dirt
and to protect flanges and pipe ends from damage during transportation and
storage.

0.6.16.2.6 Cleaning at site
During erection, the open ends of any work shall be protected at all times by
suitable temporary covers, which shall be securely fixed.
The Contractor shall make provisions for "blowing-out" procedures of the , main
steam pipe work by steam and shall provide any branches, temporary. pipe
work and supports that may become necessary. Disconnecting and remaking
of points shall be included.
After boiling-out of the boiler and blowing-out of the several pipe systems the
systems have to be passivated. The proposed process shall be fully described
by the Contractor and shall be subject to the Engineer's approval.
On completion of the cleaning processes, an inspection shall be carried out in
the presence of the Engineer, to ascertain the effectiveness of the processes
just completed.
The criteria to be used for inspection
absence of mill scale, deposits and loose
passivated surfaces and the absence of
be carried out under clean conditions and
so requested by the Engineer.

of accessible surfaces shall be the
debris, the presence of a clean and
untreated areas. The inspection shall
with internal drum fittings removed, if

It shall be the Contractor's responsibility to remove from Site all chemicals and
debris accumulated during the chemical cleaning process. Any damage caused
as a result of the process shall be made good by the Contractor at his own
expense, therefore an adequate insurance cover shall be a necessity for such a
contingency.

0.6.16.2. Wall boxes and collars.
The wall boxes and floor collars shall be constructed in such a way that, if
necessary, they can be erected after the pipes are in position. Pipes passing
through roof collars shall be provided with approved weather-hoods and cowls
which shall be fixed by the Contractor.
The Contractor shall provide all the necessary wall boxes and sleeves where
pipes pass through walls, floors and roofs, also the necessary supports fot) .
any pipes laid in trenches. Roof collars shall be fitted with high coamings to
prevent rainwater from passing through the holes.

0.6.16.2.8 Bolts and nuts
All bolts, nuts, etc. shall conform to an approved Standard. Bolts or studs which
are subjected to high pressure and temperature shall be of approved high
tensile alloy steel with nuts of a suitable, approved material.
All bolts or studs shall be of steel suitably machined, at the shank and under
the bolt head. Washers shall be provided under nuts, and also under bolt
heads, if required.
The aggressive environmental conditions must be considered when selecting
material and surface protection. Bolts, nuts, etc. from suitable stainless steel
shall be applied if submerged with highly corrosive media, or where contact
with such media in case of un tightness, etc. can be expected. Dolts and nuts
for outdoor installations, pipe installations in trenches or other applications shall
be galvanised or cadmiumized if requested by the Engineer.
Dolts, nuts made from high temperature resistant materials and ones installed
in enclosed parts of machines are not concerned of this regulation

0.6.16.3 Piping design criteria
The pipe work shall be designed, fabricated, erected, inspected and tested on
the basis of the currently approved applicable standards and codes such as
DIN, American standards (ASA; ASTM; ASME; A WW A), Japanese standards
or equivalent and the additional requirements as set out below.
For the HP Live Steam and Re-heater System high alloy steel, for example
material P91 (XI0CrMO VN b 91) is preferred.
For the main cooling water system GRP is preferred (see article D7).
The maximum flow velocities for the individual media must not bc ex exceeded
Type of pipe work

max. velocity

Steam lines:
High-pressure live steam lines (PN > 64)
Intermediate-pressure steam lines (PN
25140)

60 m/s
40 m/s

Low-pressure steam lines above 5 bar

35 m/s

Low-pressure steam lines < 5 bar

25 mls

Vacuum lines

80 m/s

Saturated steam Iincs

20 mls

Water lines (Feedll'ater, cooling water,
condensate etc.):
Feedwater suction lines

0.5-2.5 m/s**

Feedwater discharge lines

3-5 m/s

Other suction lines

1.5 m/s

Other discharge lines

3.0 m/s

Fuel lines:
Coallair lines

25 m/s

Fuel oil suction lines Fuel oil

1.0 m/s

discharge
Air Lines:

2.0 m/s

Compressed air lines

20.0 m/s

• The design and routing of the feed water suction lines must be optimized considering the allowable
velocity or depressurization caused by load changes.

The following standard pipe sizes shall preferably be used for main process
lines:
Nominal
Diameter in mm: 25, 50, 80, 100, 150, 200, 250, 300, 350, 400, etc.
inch: 1, 2, 3, 4, 6, 8, 10, 12, 14, 16,
Pipes with a diameter size smaller than 25 mm (one inch) may be used only
for control air, control oil, chemical dosing, scaling water, instrument
connections, sampling pipes and other instrument and analysis lines.
For the design of safety valves installed downstream of reducing stations,
high pressure bypass valves or equivalent control valves, the maximum
throughput of the fully open reducing or bypass valve including injection
water quantity is to be taken as the basis for calculation. All cross sections
and lines for safety devices that protect against excess pressure (safety
valves, rupture discs and similar items) must be designed to ensure the
necessary blow-off rate and fault free functioning
All safety valves shall have a test certificate issued by an approved authority.
The design pressure is equal to the response pressure of the devices
protecting the piping. In the case of pump discharge lines a pressure corresponding to 1.1 times of the shut-off head of the pump at the ambient
temperature is to be taken as the minimum design pressure. The main cooling

water and seawater supply systems must be designed according to . the water
hammer calculation.
The design temperature is the highest possible fluid temperature occurring
in the length of line concerned. Possible tolerances of the temperature control
system and any temperature allowances provided by the requirements of the
standards shall be considered.
For live steam lines the design pressure of the boiler shall be taken as the
design pressure of these lines up to the inlet of the turbine main stop valves.
In addition to the required wall thickness in accordance with calculations, a
corrosion allowance of 3 mm shall be added for unprotected carbon steel, 1.5
mm for alloy steel, and 0.5 mm by stainless steel.
For the piping systems with a nominal pressure specified as
2401, or equivalent, the drainage and ventilation facilities
double valves.
All
vents,
drains
pressure/temperature
points with covers.

or
dump
shall lead

PN > 40
shall be

as in DIN
fitted with

points
with
more
than
10
bar/1000 0C
operating
to the flash tanks and into funnels at visible

Guidelines for the design and construction of pipe work and accessories
•Design and
correspond
standards.

construction of
to the present

all parts of the pipelines and accessories should
state of the art and shall be based on the latest

•The pipe work and its accessories shall be designed and arranged so that all
parts
subject
to
operation
and
maintenance
can
be
operated,
inspected,.
maintained and replaced without difficulty and with a minimum of effort. All
important parts must be accessible.
•Provisions to allow for isolation and for access must be foreseen on all parts
subject to acceptance resets by the local authorities.
•The nominal bore of gate valves shall be the same as the nominal diameter
of the pipeline in which they are installed.
•None
of
the
forces
and
moments
transmitted
by
the
pipes
to
connected
machines,
apparatus
and
other
components
must
exceed
the
maximum
permissible
values,
given
by
the
manufacturers
of
these
items.
Attachments
to turbine foundations shall be carried out only as agreed with the turbine
manufacturer.
•All steam traps shall be provided with a bypass and lines which open to a
funnel.
•As

far as expansion joints and other parts of pipe work are concerned it shall
be borne in mind that differential settlement can occur. The reaction forces
and moments of the piping system to be withstood by fixed points~ walls,
foundations
and
other
dvil
structures
shall
be
reduced
to
the
utmost
minimum by suitable means (e.g. expansion joints shall be provided where
required).



Since the steam pipes may be filled with water for a short time (e.g. when
flushing or pressure testing), supports shall be dimensioned accordingly. The
load information to be given by the Contractor to the civil designers shall
take account of this requirement.



The pipe support structures shall be designed to minimize heat transfer.



The installed pipe work with its supports and other components shall not
obstruct
gangways
(min.
1000
mm
wide),
maintenance;
escape
routes
etc.
Overhead piping shall have a minimum vertical clearance of 2.3 meters, in
pump rooms 2.45 meters and 6 meters above roadways.



Main pipe ways shall be designed to accommodate 20% more lines than is
required for the initial installation. When designing sleeper ways, allow space
for adding 20% additional sleeper width.



Pipe spools for HP steam, feed water piping and all steel pipes > DN 50
shall
be
cleaned
internally
prior
to
delivery
by
shot
blasting
(no
sand
blasting) at the workshop with iron particles to SA2 1/2 or by acid cleaning,
and shall be property protected against corrosion.



Pipe ends
temporarily
installed.



The
Contractor
shall
submit
a
detailed
description
of
proposed
steam
blowing and other cleaning procedures for all pipelines, and no part of this
work shall be started until these procedures have been approved by the
Employer. Temporary silencers shall be provided for this.



The
Owner/Owner's
Contractor to modify
obtain acceptable results.



The
contractor
shall
furnish,
install
and
dismantle
hangers, anchors, etc. required for cleaning all piping system.



To the extent that hot fluids can accumulate in pipe sections isolated for
maintenance
purposes
(including
control
valves
with
injection
water),
drains
with hand-operated shut-off valves are to be provided for the safety of the
personnel
(block
and
bleed
systems)
.
Furthermore
the
Contractor
shall
safeguard
the
piping
systems
against
over-pressurization
caused
by
thermal
expansion of blocked-in fluids by adequate means.



AH welding shall be carried out according to relevant standards.
reasons as many welds as possible are to be carried out of the workshop.



Welding ends of all piping must be carefully prepared before welding. The type
of butt welding ends of valves, control devices, orifices, etc. shall be specified by
the Contractor and must be given to the manufacturers of these components in
due time prior to their start of work if necessary/post weld heating treatment. If
there are differences in the wall thickness and/or different materials of piping
and valves with butt-welding ends, the necessary transition pieces must be
provided by the manufacturer of the valves



Control valves should have flanged connections.

and
branch
connections of
underground
piping
during
installation
if
the
connecting
pipe
is

representative
any of his

reserves
the
right
cleaning .procedures if
all

shall
not

to
found

be
sealed
immediately

require
the
necessary to

temporary

For

pipes,

quality




Socket welds are not permitted for lines above DN 50, for corrosive medialines or for lubricating oil
lines.

After completion of the weld joint, the welder must mark with indelible
crayon his
work was
welders.

identity number and the last two digits of the year
completed on the pipes. The Contractor shall keep

in
a

which the
record of

•The
Contractor
shall
provide
suitable
thimbles
and
flashing
where
pipelines
pass through floors and walls. Floor thimbles shall be installed to provide 90
mm projection above the finished floor surface.
•A

flexibility analysis must be performed
an operating temperature > 120°C.

for

all

piping

systems

DN

>

80

with

•The
piping
stress
and
flexibility
analysis
standards.
Recalculation
must
be
taken
actual weight and dimensions.

shall
be
based
on
the
relevant
into
consideration
as
built
condition,

•Pipe
materials,
bends
and
applicable material standards.

be

fittings

shall

tested

in

accordance

with

the

Pipe supporting elements
Constant
support
hangers
shall
be
provided
at
all
locations
where
it
is
necessary to avoid transfer of stress from that support to another support or to
an
equipment
terminal,
and
at
other
support
locations
where
vertical
movements of the piping are too large to be properly handled by variable
support
springs.
Constant
support
hangers
shall
be
of
a
design
that
will
compensate for the normal variation in the supporting force of the helical coil
springs, thus providing constant supporting force throughout a total travel range
which shall be at least 20 mm greater than the actual maximum movement of
the piping.
The supporting arrangements - if applicable weight of the piping systems when full of
chapter test at site, hydraulic test).

shall be capable of supporting the
water during hydraulic testing (see

Constant support hangers and spring hangers shall be equipped with a means
of
locking
the
springes)
against
movement
during
erection,
hydrostatic
testing
etc. The use of counterweights in substitution for support spring assemblies will
not be permitted.
Support spring hangers shall be of the enclosed spring type, and shall have an
embossed on factory load indication scale showing the hot (operating) and cold
(ambient)
positions.
Each
spring
assembly
shall
incorporate
an
adjustable
hanger rod coupling to permit load adjustment. All support springs shall
be
designed
to
permit
at
least
±
10%
field
load
deviation
from.
the
factory
calibrated load.
The supporting force provided by variable support type spring hangers shall not
change by more than 20% between the cold and hot positions, and supports of this
type shall not be used at any point where such a change in supporting force cannot
be safely permitted. Variable support spring hangers shall incorporate springs with
maximum working range Iength in order to reduce the overall length of the
assembly.

All
pipe
hangers
and
support stands
shall
be
attached
to
the
piping
and
structural supports such that they will be vertical when the piping is at operating
condition. So far as practicable, hangers and supports shall be of the same
type and component assembly.
All hangers shall be carefully adjusted. After plant start-up checks shall confirm
that all hangers and supports are in the correct position.
The Contractor shall prepare a complete documentation of a1\ pipe hangers
and supporting elements. These documents shall contain the following
information:


identification coding number


loads, forces and moments, and their directions at all supports, hangers at
normal operating conditions, etc.



magnitude and directions of the movements at the loading points



measurements of the loading points referred to the axes 'of the buildings



item No. of the supports, hangers etc. according to the piping group



material specification for the supporting parts.
All
hangers
shall
be
carefully
adjusted.
After
plant
confirm that all hangers and supports are in the correct position.

start-up

The Contractor shall prepare a complete documentation of a1\
and
supporting
elements.
These
documents
shall
contain
information:


checks
pipe
the

shall

hangers
following

identification coding number


loads, forces and moments, and their directions at all supports, hangers at
normal operating conditions, etc.



magnitude and directions of the movements at the loading points



measurements of the loading points referred to the axes 'of the buildings



item No. of the supports, hangers etc. according to the piping group



material specification for the supporting parts.

Trace heating
Trace heating shall be provided for fuel oil pipes and other pipes as required.
Electric type trace heating is preferred.
Protection of buried pipe work systems (as far as not installable in ducts)
All buried pipe work of steel or cast iron or other materials prone to
shall be protected from corrosion by catholic protection and a system
wrapping to be applied in the workshop.
The design of the catholic protection system(s) shall
and authorized company under consideration of the following:

be

executed

• impressed current-type catholic protection systems shall be employed; only if

by

a

corrosion
of tape
specialist

the calculated current required is too low may suitable sacrificial anodes be
used for protection,


coating of a minimum finished thickness of 6.5 mm for bitumen or 2.5 3.5 mm
for plastic coatings (PVC or PE), applied for tape wrapping spirally with an
overlap of 50%, the coated pipeline supplemented by suitable, catholic
protection systems,



suitable insulating joints arc to be provided where systems arc to be separated
and, as a minimum, locations where there is a change from above-ground to
buried piping,



the designed catholic protection shall be a completely functioning system in all
respects according to the state of the art and shall also include the appropriate
equipment for measurements .

0.6.16.4 Welding and heat treatment
0.6.16.4.1 Responsibility
Each Contractor must have the necessary facilities available to ensure that the
materials are properly processed and all tests can be carried out.
It must have his own supervisory staff and trained workers for the manufacture.
Each Contractor shall be responsible for the quality of the welding carried out
by his organization and shall conduct tests not only of the welding procedure to
determine its suitability of ensuring welds which will meet the required
specifications and tests, but also of the welders and welding operators to
determine their ability of applying the procedure properly. No production work
shall be undertaken until both the welding procedure and the welders or
welding operators have been qualified.
The Owner/Owner's Representative's acceptance
not releases the Contractor of his responsibility.

of

welding

execution

docs

0.6.16.4.2 Required documents
The Contractor shall maintain the/following documents for welding, tests and
heat treatment:


list of welding supervisors



current log of maintenance, examination, calibration and identification of
welding equipment as well as drying and warming equipment for welding
auxiliary materials



instruction for issue and return of welding auxiliary materials their drying and
warming, storage and identification



list of welding procedure qualification including test results (PQR) approved by
an internationally recognized authority



list of qualified welders, documentation of welders' qualification records




welding schedule, welding procedure specification
inspection plan and procedure for testing of weld edges and complete weld



instruction for handling of non-conformities


record of performed welding and repairs by welding, their test results and the
welder or welding operator who made them



current log of maintenance, examination, calibration and identification of heat
treatment equipment



heat treatment plan including sketch of temperature measuring points and
temperature-time diagram



manner of temperature control



members of the unit responsible for the performance of heat treatment



record of all performed heat treatments
Prior to any work on welding, the above-mentioned documents shall be
available to the Owner/Owner's Representative and be subject to review and
comments by the Inspector.

0.6.16.4.3 Welding procedure qualification
Each Contractor shall furnish proof in a procedure qualification test adapted to
the manufacturing process that he is fully conversant with the welding
procedure used.
Supplementary tests will be necessary if the materials, dimensions or jointing
methods are changed beyond the scope of procedure qualification test.
The specific data including the test results shall be recorded in a procedure
qualification test record and approved by an internationally recognized authority
and shall not date back for more than 3 years.
It is permissible for a Contractor
performed by another organization.

to

have

the

welding

of

the

test

welds

0.6.16.4.4 Personnel qualification
The Contractor shall employ his own welding supervisors. The name of the
supervisor shall be made known to the Owner/Owner's Representative.
Welding supervisors must be persons who, through their training, experience
and ability, arc considered suitable for the job after an adequate job training
period.
The Contractor shall only employ welders who have passed a qualification test
as stated in DIN or ASME or an approved standard with equivalent i
requirements.

I f not otherwise agreed upon, the tests and certificates shall be valid as per
adopted pressure code.
The regular renewal of the qualification of welding personnel shall be done
according to the same standard and specification used for their initial
qualification. If at any time, in the opinion of the Owner/Owner's Representative, the work of any welder appears questionable, such welder will be
required to pass additional qualification tests to determine his ability to perform
the type of work on which he is engaged. All such additional qualification tests
and the physical tests on the welded specimens shall be made at the expense
or the Contractor and in the presence of the Owner/Owner's Representative.
The sample welds shall be carried out on specimens of similar shape,
thickness and chemical analysis as for the material to be welded, and in a
position which shall represent as far as possible the worst conditions under
which actual welding would take place.
The procedure of preparation of the test pieces, and the standards to be used
for the examination shall be in accordance with the relevant standards or as
may be agreed upon between the Contractor and the Owner/Owner's
Representative.
Each qualified welder and welding operator shall be assigned an identifying
number or symbol by the Contractor which shall be used to identify the work of
that welder or welding operator.
The performance qualification tests for welders and welding operators
conducted by one contractor on ASME base shall not qualify a welder or
welding operator to do work for any other manufacturer or contractor.

0.6.16.4.5 Welding process
0.6.16.4.5.1 Welding schedule/welding procedure specification
Each Contractor shall qualify the welding procedure specification by the
welding of test coupons and the testing of the specimens according to
relevant standards. The record of the procedure qualifications test showing
the welding data and test results approved by internationally recognized
authority, shall be the basis of a welding procedure specification or welding
schedule.
The welding procedure specification or welding schedule shall list in detail:


the relating Procedure Qualification Record (POR)



the various base metal to be joined



the welding auxiliary materials to be used



the range of preheat



the heat treatment plan



thicknesses



the positions



the sketch of the joint and number of weld passes



welding sequences especially for tank welding and large equipment


inspection plan and test procedure for testing of weld edges and complete
weld.
Prior to start of welding, the welding schedule and test procedure shall be
available at workshop respective site.

0.6.16.4.5.2 Welding inspection and records
The Contractor shall maintain and make available to the Owner/Owner's'
representative both at works and at Site, adequately indexed records of all
welding, weld inspection and tests and repairs.
The extent of the weld inspection, the final weld quality and the method of
examination shall be such as stated in





the relevant standards and codes
the sub-section of this Contract
the test procedure
the welding schedule or welding procedure specification
In case of conflict the more stringent requirements shall be valid.
The Contractor shall also establish a procedure whereby welded joints can be
identified as to the welder or welding operator who made them if requested by
the Owner/Owner's representative or as stated in sub-sections of the
Contract.

0.6.16.4.5.3 Welding auxiliary materials
The requirements of the welding auxiliary materials' manufacturer shall be
strictly adhered to.
The Contractor shall prepare written instructions for issue
welding auxiliary materials, their drying and warming if
handling, storage and identification.

and return of
required, their

0.6.16.4.5.4 Joint preparation and assembly
All joints shall be prepared according to the relevant standards and to the
welding schedule,
As far as possible, the preparation shall be carried out by machining. Where
thermal cutting is used, the weld edges shall be machined afterwards.
Butt-welding on pipes shall be performed without the use of backing rings.
Surfaces to be welded shall be free from oil, grease, foreign matter, corrosion products and humidity, and shall be free from protective coatings unless
permitted by a qualified welding procedure.
Tack welds used to secure alignment shall either be removed completely or
their stopping and starting ends shall properly by prepared by grinding and, if
required by testing so that they may be satisfactorily incorporated into the
final weld.

Tack welds shall be made by qualified welders only.
The welder's identification number of symbol must be stamped near to each
executed welding, where requested by the Owner/Owner's representative or
as stated in sub-sections of the Contract.
In order to cope with the requirements for a surface protection suitable for the
prevailing aggressive environmental conditions and to' avoid corrosion in
crevices, all welded steel works for structures has completely to be seal
welded.

0.6.16.4.5.5 Non-conformities
The Contractor shall issue an instruction sheet for handling of nonconformities.
Each non-conformity has to be noted by him. He shall present a proposal of
acceptance or removal of the defect to the Owner/Owner's Representative.
Every major repair procedure needs the approval of the Owner/Owner's
Representative.
If heat treatment has already been performed, the repair documents for
approval shall include the heat treatment plan after completion of the repair.

0.6.16.4.6 Pre-heating and heat treatment
0.6.16.4.6.1 Heal treatment equipment
Apparatus and equipment used for heat treatment shall be inspected and
checked for correct operation.
The Owner/Owner's representative may ask for the current log of
maintenance.

0.6.16.4.6.2 Pre-heating
If pre-heating is required according to welding schedule, the temperature
shall be maintained during the welding operation. In case of interruption of
welding and preheating, a stress relief heat treatment shall be done prior to
the interruption.
In any case, the welding schedule or welding procedure specification for the
material being welded shall specify the minimum preheating temperature.
Preheating for welding or thermal cutting may be applied by any method
which does not harm the base material or any weld metal already applied or
which does not introduce foreign material into the welding area which is
harmful to the base material or weld

0.6.16.4.6.3 Heat treatment
Heat treatment prior to and after welding in order to achieve stress relieving
shall be applied as specified in the internationally recognized standards and
Codes.

The Contractor shall issue a heat treatment plan showing the temperaturetime diagram
and
a
sketch
with
the
temperature-measuring
points
<Illd
describe the manner of temperature control.
Welding after final stress relieving is basically prohibited. The relevant piece
shall undergo a new stress relieving process if any welding has been
performed afterwards.

0.6.16.4.6.4 Records of heat treatment
The Contractor shall maintain and make available
records
of
all
heat
treatments
performed
to
representative and inspector both at the works and at site.

adequately indexed
the
Owner/Owner's

0.6.16.4.7 Documentation
The above-mentioned records and instruction sheets and documents requested by this Contract or relating standards shall be stored by the Contractor during the erection time and shall be part of the general power plant
documentation.
0.6.16.5 Valves, Steam traps, condensate drainers, safety valves, control valves
The Contractor shall design and supply all valves and their accessories.
required for the safe, efficient and sound operation and maintenance of the
plant based on the appropriate standards. They shall comply as a minimum
with the design criteria of the relevant piping.
For reasons of plant standardization, the Contractor shall co-ordinate types
and makes of all valves in his supply and that of his sub suppliers.
Design, construction, fabrication and testing of the valves shall be in
accordance with the approved standards. The stipulations of this section will
take precedence if these are more stringent than the approved standards.
All valves shall be suitable for the media and for the service conditions an~
those performing similar duties shall be interchangeable.
All valves shall conform as a minimum to the PN 16 pressure rating.
Basically the following types of valves shall be used:

• globe valves
• gate valves
• butterfly valves

• lift check valves
• swing check valves
• ball valves

up to and including DN 50
ON 80 and above
DN 400 and above for LP steam and exhaust
steam (DN 80 and above for waterlines
(cooling water, process water etc.), operating
temp. max.180°C
up to and including DN 50
DN 80 and above
DN 25 and above (fuel oil, natural gas,
compressed air)

In vacuum service and wherever otherwise necessary to prevent the entry of
air,
valves
shall
be
provided
with
suitable
sealing
facilities.
Where
applicable,
the
valves
must
be
suitable
for
outdoor
installation
under
consideration
of the special climatic and environmental conditions of the site.
Unless otherwise
position.

agreed,

all

valves

shall

be

fitted

with

All valves shall be positioned so as to be readily
and
maintenance
from
permanent
floors,
catwalks
required, valve spindles shall be lengthened to have
height
approximately
1
meter
above
the
operation
valves shall be installed in concrete culverts.

the

spindle

in

upright

accessible for operation
or
platforms.
Where
the hand-wheel at 'a
level.
All
underground

All valves shall be closed in a clockwise direction when looking at the face
of the hand wheel. The valves shall have rising spindles and non rising
hand wheels. Plastic valve hand wheels will not be accepted.
HP and large size gate valves to be opened
be equipped with pressure equalizing valves (globe valves).

under

differential

pressure

shall

All valves (especially including ball valves) shall be fitted with
indicators to
determine
the
valve
position.
In
the
case
of
valves
fitted
with
extended
spindles, indicators shall be fitted both to the extended spindle and to the:
valve spindle.
All
globe
characteristic.

valves

shall

be

equipped

with

throttling

In general, LP safety valves, butterfly valves, ball
as all control valves shall be flanged. All valves
condensate,
HP
safety
valves
(inlet
side)
shall
sponding to the connected pipes.
Design
of
valves
and
materials
dards. They must be chosen in
and to corresponding pipe work .
For limiting hand wheel forces,
necessary to install gears and drives.

control

and

with

parabolic

valves and orifices as well
for steam, feed water and
have
welded
ends,
corre-

used
must
comply
accordance with the

for

cones

with
the
relevant
stanrequirements to be met

operation

purposes

it

may

be

The max hand wheel force of 25 deka Newton must not be exceeded.
All block valves DN
manual
override.
The
which can be locked.

500 arc to
actuators
arc

be
to

provided with electrical
be
operated
by
local

Preferably
electrical
actuators
shall
be
installed.
for fitment to valves and floor-stands with hand
and
provision
to
switch
over
from
electrical
to
versa (see chapter actuators).
For
pneumatic
or
hydraulic
actuators
Fail-safe functions shall be incorporated.

similar

actuators with
control
points

Actuators
shall
be
suitable
wheels for manual operation
manual
operation
and
vice

requirements

must

be

fulfilled.

The Contractor shall furnish and install steam traps at each low point.
steam
trap
installation
shall
include
a
permanent
strainer,.
upstream
downstream globe valves and a globe valve as free drain. Steam traps
be supplied with weld ends.
Drain traps shall be provided with inlet and discharge valves, vents
controlled
bypasses
and,
when
discharging
into
a
closed
header,
be provided with discharge non-return valves.
Steam traps shall preferably be of the thermodynamic
multistage nozzles selected to suit the service conditions.

or

Each
and
shall

and handshall
also

bimetallic

type

with

No traps which incorporate internal screens or check valves shall be used
unless specifically required.
Each trap shall be sized to provide ample capacity at the
differential
pressure,
and
to
open
the
orifice
at
maximum
tial pressure.
Condensate drainers such as
lines shall be of the ball-float type.

used

on

LP

saturated

steam

minimum
working
or

working
differen-

compressed

All gate valves shall be of the fullway gate type and when in full
position. the bore of the valve shall not be obstructed by any part of the
The internal diameter of all valves at the end adjacent to the pipe work
be the same as the internal diameter of the connecting pipe.

air
open
gate.
shall

All valves shall have bolted gland stuffing boxes. Screwed glands and
bonnets will not be accepted.
Spindle glands shall be of the bridge type. In
spindles
shall
have
back-scaling
seats
to
allow
glands with the valve open under pressure conditions.

all cases
renewing

HP gate valves shall be equipped with
self scaling lid
scaling lid covers shall be equipped with a safety device
shut-off
valve
and
interlocking
system.
This
system
must
the authorities.

where applicable,
of
the
spindle

covers. The selfat the body with
be
approved
by

All valves of the HP piping systems shall be suitable for pickling.
The valves for live steam, HP feed water and HP injection
made of forged steel. Forged steel or cast steel shall be used
ing systems. Valves made of gray cast iron are not acceptable.
Acceptance
certificates
for
piping
components
to the Owner/Owner's representative for approval.

and

valves

water shall be
for the remain-

shall

a) Relief valves shall be installed in the vertical upright position.
b) The outlet piping of relief valves discharging to a closed
as a blowdown or Dare header shall be arranged so that
line flows down to the header without pockets.

be

delivered

system, such
the discharge

c)

Relief valves in hydrocarbon service discharging to atmosphere shall
have outlet piping extended not less than 3.6 meters above highest
working level or 4.5 meters above roof of nearest building within a
radius of 12 meters.
d) All relief valves discharging to atmosphere shall have a weephole located at
low point, and for hydrocarbon relief valves a steam dispersal line, operable
from grade.

0.6.16.6 Insulation
Thermal insulation
The thermal insulation shall be designed and installed in accordance with the
chosen standards, considering the following minimum requirements:



Insulation shall be provided for personnel protection, heat conservation, noise
reduction and for prevention of the formation of condensation on all pipe work
and equipment whose external surface temperature exceeds 60°C.
All insulation material has to be made from non-asbestos materials.
All pipes and equipment to be insulated must be indicated on the flow sheet and
technical data sheets with the following code letters:
HI

= heat insulation

CI

= cold insulation

C
WI

= chilled-water insulation

PPI

= personal protection insulation

Type of insulation materials
The following insulating materials may be used:
Piping DN <;250 preformed shape blankets
Piping DN > 250 blankets
The mats shall be stable in shape, chemically inert, free of sulfur and alkali,
resistant to water and steam, non-flammable and capable of withstanding
continuous exposure to the pipe design temperature. The mats used for insulation
of stainless steel equipment shall have a chloride content of less than 0.15%. Under
no circumstances may asbestos or asbestos containing materials be used.
The
material
will
have
the
allowance):
following physical/chemical properties (± 10%



service temperature up to



density



water adsorption

6000 C
120 kg/m3



specific heat capacity

0.5% weight



compressive strength

0.84 kJ/kg UK



conductivity versus temperature
Average temperature (OC)

0

50
100
150
200
250
300
•Conductivity allowance is limited to + 5 %.

20 kPa
Blanket (W/m K)

0.034
0.040
0.048
0.058
0.070
0.083
0.100

The manufacturer's name
package of insulation material.

and

the

material

properties

shall

be

labeled

on

each

The insulating mats shall be stitched to galvanized wire mesh using galvanized steel
wire. The mesh size shall be approximately 19 mm.
For special purposes such as for turbines, boilers, etc. spray type insulation or
insulation brickwork (for example calcium silicate) may also be applied. The special
insulation materials shall be stated by the Contractor and their design shall match the
overall design and guarantee the requirements stated in the specifications.

Type of insulation setting materials
The surface cladtling shall be made of aluminum sheets specified as "99.5% aluminum
grade II24, mill finish surface" in accordance with UNI 9001 or other equivalent
standard, manufactured in sheets
with the following minimum thickness:

Outer
insulation
to 150 mm
Outer
insulation
to 450 mm
Tanks and other
ment

diameter

up

diameter

up

large

equip-

Tank tops shall be provided with
man's weight.

Sheet
thickness
0.7 mm
Sheet
thickness
0.9 mm
Sheet
thickness
1.2mm

insulation strong enough to support a

The sheets shall be secured and connected at the longitudinal scams with at least five
stainless steel self-tapping screws per meter run.
Plain sheets for fiat surfaces shall not exceed 1 meter square and shall be stiffened by
crimping.
At the longitudinal and circumferential joints, the sheets shall overlap by at least 50
mm so as to drain off the liquid and to trap the liquid in the insulation.
Places at which the metal sheets are penetrated for pipe hangers,
sockets, etc. shall be sealed with funnel-shaped recesses or sheet metal rims.
The seams and penetrations of any sheet metal insulating jacket installed

thermometer

outdoors as well as
spray etc., shall be
silicon based sealant.

in the boiler and turbine
sealed against penetration

The inside of the
from the wire mesh
equivalent).

aluminum jacket
of the insulating

shall
mats

house in
of water

areas with risk of water
by means of a suitable

be protected against contact corrosion
by suitable means (e.g. Kraft paper or

In the case of pipe insulation thicknesses greater than 60 mm, where insulation
blankets are used spacers shall be provided at maximum intervals of 950 nun to
ensure a uniform insulating thickness on all sides and a perfectly circular shape"
of the sheet metal jacket. The sheet metal jacket shall be supported by support
webs (for pipe diameters below 100 nun) and enclosed support rings (for pipe
diameters 100 mm and above). If the enclosed support rings are not provided with
ceramic spacers, the spacers made of steel shall be insulated with one heat
insulation strip in the case of operating temperatures of up to 200°C, and with two
heat insulation strips where the operating temperature exceeds 200°C.
To provide protection
support ring shall be
edges.

against contact
fitted with heat

corrosion, the
insulation tape

external circumference of the
1 mm thick with two woven

Insulation of furnace and main parts of the boiler
Insulation of up to 80 mm layer thickness
that in two layers with offset joints and seams.

shall

be

applied

The mats shall be secured in position by suitable means
another by galvanized binding wires of diameter 1.0 mm minimum.

in

and

one

layer,

stitched

above

to

one

Insulation of flanges, valves and fittings
All flanges, valves and fittings shall be provided with two-piece or multi-part caps
made of aluminum sheet of the specified thickness. Each piece or part shall be
double jacketed and the various ports shall be held together by quick release
clamps or lever hooks to facilitate assembly and disassembly.
All caps of the welded-in fittings shall be made longer by approximately twice
the insulation thickness so that the welding seams will be exposed after removal
of the cap.
All manholes shall be provided
wherever possible. Such covers
clamps.

with
shall

heavy duty hinged insulated covers
be secured with easily accessible

Insulation or tanks and process equipment:
Tanks and process equipment shall be
that the insulating material shall not
galvanized steel bands.

insulated in the same
be attached by wire

Spacers shall be welded to process equipment only if
satisfactory
retention
of
the
insulation.
Welding
of
equipment is subject to approval by its manufacturer in writing.

way
but

this is
spacers

as
by

pipes,
using

except
strong

essential for
to
process

Insulation for personnel protection
Wherever insulation is necessary
applied around that portion of
equipment that is located within
1.20 m horizontally to the side or
ladder.

only for the protection of personnel, it shall be
the pipeline length or 'to that surface of the
2.50 m above the passage way floor, or within
at the end of any floor, platform, walkway, stair or

Where necessary, drain lines and valves shall be provided with a contact guard of
minimum 30 mm thickness against accidental contact, and this shall be installed in
the same way as the other insulation.
Where insulation is provided for heat conservation it shall reduce the heat loss to
an economic minimum. The maximum heat loss shall be 200 W/m2 at an ambient
temperature acceptable at 30°C and a wind speed of 2 m/s.
For personnel protection all surfaces with a temperature above 50°C and which
are within the reach of personnel shall be provided with protection insulation. The
maximum insulation surface temperature shall be 60°C.
Cold insulation
Pre-fabricated
equal quality).

block

and

sleeves

insulating

pieces

made

from

polyurethane

(or

Pipes and flanges shall be cleaned and given an external protection; coat of paint
to 0.35mm (or equivalent).
Prefabricated pieces shall be fitted tightly to the pipes. A self-adhesive
shall be wrapped tightly around the hard foam shells to serve as a steam seal.

plastic

foil

The material and thickness of insulation for the various temperature groups of cold
piping shall be as given in the following table:

Temperature
of pipe
28ucto 5°C

if required for
condensation

Piping sizes
mm
100 and smaller

125 and larger

Insulation Material and
minimum thickness mm

25 thick fiber glass or
rockwool
40. thick fiber glass or
rockwool

Insulation
flange
joints
required

required

Materials and thickness of insulation for piping and equipment outside the
building exposed to weather:
The material and thickness of insulation for the various temperature groups of
piping exposed to the weather outside of buildings shall be as specified in this
article, except that the thickness will increase 13 mm in excess of thicknesses
indicated therein.
Chilled-water insulation
Material: Polyurethane foam or equal 40 to 50 kg/m 3 Spacing rings shall be fitted

around the pipes at an interval of 800 to 900 mm. Aluminum-sheet covers shall be
screwed (stainless steel) to the spacer rings. The overlapping has to be in
accordance with specified requirements of this Section. The hollow space between
the pipes and metal-cover sheets shall be spray-filled with polyurethane foam or
equivalent. .
Cut-outs in the dover sheets for pipe supports shall be sealed with a permanent
plastic putty.
Valve and flange connections have to be insulated.

0.6.16.7 Vessels, tanks, heat
exchanger
Vessels
All pressure vessels supplied under Contract shall be designed and manufactured in accordance with the relevant pressure vessel and welding standards
and codes.
The Contractor is held responsible for the correct design and dimensioning of the
apparatus.
Connections shall be provided for all pipe work, together with connection and
tapping points for instrumentation. Manholes, vents, drains, safety devices and any
platforms necessary for safe operation and easy maintenance have to be included
in design and supply.
If under any operation conditions vacuum can occur in the vessels. they shall be
designed for max. pressure and full (= 100%) vacuum.
The welding factor for all vessels is fixed to v = 1.0. The minimum wall thickness
should not be less than 10 mm, and an appropriate corrosion allowance based
upon the particular material, but not less then 1 mm.
Instrumentation and control equipment shall be provided according to the safe
service requirements. A minimum requirement is to equip each vessel with a local
level indicator, a temperature and a pressure indicator.
Manholes shall be provided as follows:
1. manhole (minimum nominal bore 600 mm) for vessels of 1.0 meter diameter
and above
2. handholes (minimum size 200 mm) for vessels below 1.0 meter diameter.
All nozzles shall be provided with flanges and shall be so arranged that practical
pipe connections are possible. The stub length for all stub pipes shall be at least
200 nun, measured from the tank wall to the flange sealing surface. In the case of
insulated vessels, the length shall be chosen so that there will be a clear space of
at least 100 mm between the cover of the insulation and the underside of the
flange. Nozzles of nominal bore DN 50 and less shall be reinforced by two ribs at
different planes.

Nozzles below DN 25 are not acceptable.
For insulated
insulation.
Manhole
arms.

covers

vessels,

of

provisions

nominal

weight

must

be

more

than

made

20

for

kg

fixing

shall

and

be

supporting

provided

with

the

hinged

All tank internals must be replaceable through the manhole. Prefabricated vessels
must as a minimum have a coat of primer applied before transport. They shall be
cleaned and internally dry. All openings must be secured closed before transport.

Tanks
Unless otherwise specified, tanks used for the storage of liquid fuels, lubricating
oil, raw water, makeup water, condensate, chemicals, etc. and tanks used for
mixing and agitation shall be of welded construction, manufactured from mild steel
plates of accepted quality and thickness in accordance with the approved relevant
standards.
All welds shall be continuous, including welds
supports (see also Article "Welding" of this Section V).

around

internal

slays,

All large tanks shall have at least two manholes each of 600
complete with covers of the bolted type, fitted with a davit for easy handling.

mm

stiffeners

inner

and

diameter

All tank nozzles shall be provided with flanges, if not otherwise specified.
Nozzles shall be
controllers and piping.

provided

where

necessary

Internal
and
external
protection
painting
according to the requirements of this Contract.

for

of

the

the

fitting

tanks

of

instruments,

shall

be

level

performed

Arrangements shall be made for the blanking off or removal of all valves or pipe
connections during sand- blasting and painting to prevent the ingress of sand or
other matter. The protective process shall be applied also to any ferrous or nonferrous parts mounted inside the tanks.

I

Heat exchanger
Heat exchangers are to be designed,
with the recognized international standards.

manufactured

and

erected

in

accordance

Only proven products shall be delivered. No cast iron components are permitted.
It must be possible to install and remove the heat exchangers without
difficulty. Lifting lugs and eyes and other special tackle shall be provided to
easy handling. '.
Tubular heat exchangers or
Where necessary the tubes
number of visual inspection
condition monitoring.

undue
permit

plate and frame type heat exchangers are acceptable.
are to be protected by impact shields. An adequate
ports is to be provided in critical areas to facilitate

Unless otherwise specified; all heat exchanger tubes and casings must be
designed to withstand 1.2 times the zero flow pressure of the relevant pump at
cold conditions, or 1.2 times of the maximum positive operating pressure, as
applicable. The minimum design pressure is 6 bar, and the design shall be proof
against full vacuum. The test pressure must be 1.5 times the design pressure.
The heat exchangers shall be designed for the maximum temperature incurred
plus 20 K.
Heat exchangers must be capable of continuous unrestricted operation with up to
10% of plugged tubes, and a corresponding factor of conservatism of at least this
amount must be used in the design of the heat transfer areas.
Considerable
exchangers.

importance

will

be

attached

to

the

ease

of

cleaning

the

heat

Where any heat exchanger part in contact with liquid can be isolated, and there is
a possibility of being heated from the other side, safety valves are to be provided
for pressure relief.
Pipes from drains, vents and safety valves are to be grouped together, and routed
to easily observable points equipped with covered funnels or to the flash tanks.
The overall design and conception of the heat exchangers and accessories is to be such that
they are suitable for the degree of automation envisaged for the individual system.

0.6.17 Electrical equipment and works
0.6.17.1 Standards
In addition to the standards as mentioned elsewhere in this document, the design
and manufacture of all electrical equipment shall comply with the latest editions of
the IEC recommendations, e. g. the following:

IEC 34
IEC 56
IEC 72
IEC 76
IEC 79

IEC 86
IEC 123
IEC 129
IEC 137
IEC 141

Recommendations for rotating electrical
machinery
HV AC circuit-breakers
Dimensions and output rating of electrical
machines
Recommendations for power transformers
Recommendations for the construction of
flameproof enclosures of electrical
apparatus
Primary cells and batteries
Recommendations of sound level meters
AC isolators
AC bushing above 1000 V
Tests on oil-filled and gas pressure cables
and their accessories
Degree of protection of enclosure for LV
LV distribution switchgear - ISC 156 LV
control gear Lighting

IEC 144
IEC 157

12
2

• IEC 162
IEC 214
lEC 269
IEC 287
lEC 292
IEC 298

Lighting fittings for tubular fluorescent
lamps
On-load tap changers
Low voltage fuses with high breaking
capacity
Calculation of the continuous current rating
of cables
LV motor starters
UV metal-enclosed switchgear and control
gear
In case IEC recommendations do not exist, other national
equivalent to German VDE or British Standards BS shall be applied.

standards

at

least

The Contractor shall provide the Owner/Owner's representative with four sets
(official, complete, unabridged and in the English language) of all relevant standard
specifications according to which the equipment is manufactured.

0.6.17.2 Standard voltages
The following 50 Hz AC voltages shall apply:




230 kV for the power feeder from/to the network
33 kV incoming sub-station for feeding construction power.
6.6 kV for motors bigger than 150 kW and for power distribution within the plant



230/400 V ± 10% for power supplies to small electric power consumers and
motors up to 150 kW, for lighting and domestic power outlets.
230 V safe AC system for uninterrupted essential supplies to consumers,
where no break in supplies can be tolerated.

The following DC voltages shall apply:



220 V DC ± 10% for supplies to emergency users of electricity, inverters and
controls
26 V DC for automatic, measurement and control systems (the voltage range at
the consumer terminals between minimum operation voltage 21 V and
maximum operation voltage 30 V must be covered by all 26 DC consumers
connected).

The general arrangement of the particular voltage level for each part of the plant
within the scope of the Contract' arid the connections of the power supply systems
can be seen from the general single line diagram.

0.6.17.3 Climatic conditions
All electrical equipment shall be entirely suitable for the use under the prevailing
site conditions (see elsewhere in this document) and be of tropical design with
vermin proofing.

12
3

0.6.17.4 Inductive interferences
The Owner may operate wireless communication equipment in the station, inside
and outside the housings of all the equipment to be supplied under this Contract.
The Contractor shall ensure that all the supplied equipment proof against any
signals emitted by this wireless communication equipment.
0.6.17.5 Color code system for switchgear, for local switching measurement-controlsignaling cabinets and for mimic diagrams
RAL 7032, pebble-gray
equipment housings.

shall

be

applied

for

all

electrical

and

instrumentation

Color code for indications, push buttons on control cubicles, panels, desks, etc.
shall be worked out by the Contractor according to the relevant IEC/VDE
regulations to be approved by the Owner/Owner's Representative.
Where the On/ Off function of a push button cannot easily be identified by the
location, this will be indicated by a sign "ON"/ "OFF" or "0"/ "1" or by color code as
se4scribed above.
Mimic diagrams to be arranged on switchgear cubicles, control panels/desks etc.,
shall be color coded as follows:

green
blue
silver

similar to
similar to
similar to

400/231 V
220/110 V DC

yellow
violet

similar to
similar to

24/48 V DC

pink

similar to

earth

black

similar to

80
15
60
02
50
15
90
06
10
21
30
17

01 0 CD
O

33 kV
11 kV
6.6 kV

R
A
R
A
R
A
R
A
R
A
R
A
R
A
R
A
R
A

o
o

similar to
similar to

o

brown
red

o
o

230 kV
132 kV

0.6.17.6 Protection class for electrical operational equipment and control
and monitoring equipment
If not specified otherwise the electrical operational equipment must be designed
to meet protection classes stated below.
Switchgear, housings for electrical equipment and electrical equipment itself must be
designed at least to:



Class IP31 if located in air conditioned areas
Class IP54 if located indoors but in non-air-conditioned areas
• Class IP54 with additional measures if located outdoors in accordance with IEC
529 and DIN 400050 (general protection requirements for enclosures).

12
4

The additional measures shall consist of sunshades, protection covers againstsplashing water
and sand, additional sealing, special seawater or acid resistive coating
etc., depending upon the particular site conditions.
General diffusing lights in switchgear rooms and lights for figments in. luminous
ceilings for offices and control room must be designed at least to class IP32. The
lamps for external lighting and halide lights for internal lighting must have protection
class IP54.
Electrical operational equipment liable to occasional submersion or operation
continuously under water (such as submersible motor-pumps), is to be designed to
meet class IP58 protection in accordance with IEC 34-5.
Electrical operational equipment which must be installed in areas exposed to danger
from explosions must have the required explosion-proof design appropriate to the
flash-point group classification of the explosive mixture as laid down in IEC 79 and
VDE 0 170/0 171. Attention must be paid to VDE 0165 with respect to the use of
electrical operational equipment in workshops and storage premises exposed to the
risk of explosions.
In all rooms and areas where the local and operational conditions and
surroundings can lead to the accumulation of gases, vapors, mists or dusts which,
in combination with air, form explosive mixtures, the operational equipment and
installations to be used iri these circumstances must be of ~ explosion-proof
design. All operational equipment must be designed to comply with the class of
protection dictated by the ignitable mixture (e.g. compression-proof casing,
external ventilation, inherent safety, etc.).
Electrical operational equipment should be located outside rather than inside
buildings or other structures exposed to the risk of explosion. Whenever
operational equipment has to be installed within areas liable to the risk of
explosion, protection against explosion must, in general, be applied wherever
explosive mixtures can arise. In this connection, the ignition of explosive mixtures
must be reliably prevented by adopting the correct choice of design and
construction of the operational equipment and the incorporation of supplementary
safeguards where applicable.
Electrical, chemical, thermal and mechanical influences must on no account
impair, in any way, the protection afforded against explosion. In particular the high
ambient temperatures and the influence of nearby heat sources at the installation
point must be taken fully into account.
0.6.17.7 Protective measures
In view of the potential dangers of electrical power, the following measures are
required for the protection of life, equipment and materials. Basically, all 'live' parts,
i.e. all parts of electrical, operational equipment at an electrical potential above or
below earth potential when in operation, and with a rated voltage over 42 V, must
be insulated or covered so that they cannot be touched accidentally
In addition, measures must be taken by the Contractor to prevent the occurrence
or persistence of excessively high contact potentials on conductive parts of
electrical operational equipment (frames etc.) brought about by faults in insulation.
For installations up to 1000 V, voltages over 65 V are considered to be excessive
contact voltages. Within enclosed electrical installations, with voltages over 1000

12
5

V, the contact potential shall be according
section 4. (Verein Deutscher Elektroingenieure)
The following rules and regulations
measure and in earthling procedure:

are

to

to

be

the

values.

observed

in



IEC 79 and 364 including VDE 0100 and 0190 for installations up to 1000 V



VDE 0101 and 0141 for installations above 1000 V.
In areas exposed to the hazard of
VDE 0165 are to be adhered to in
and equipment.

given

in

carrying

VDE

out

0141

protective

explosion, the protective measures outlined in
the erection and installation or electrical plant

Protective measures for installations up to 1000 V
Protection against direct contact
All 'live' parts of electrical operational equipment that can be reached by hand must
be protected against direct contact either by means of insulation or through
constructional design, position or arrangement, or by means of special devices. If,
in the case of enclosed switchgear or control cabinets, access is required in the
course of normal operation (e.g. for replacing fuses). protection against direct
contact must still be ensured when the switchgear or control cabinet has been
opened up.
Protective insulation
Protective insulation is to be provided by means of additional insulation over and
above the insulation provided for operational purposes. This measure must prevent
the occurrence of a dangerous contact potential.
Use of low voltages as a safety measure
This safeguard applies to all equipment, which is required to operate in metal
enclosures,
boilers,
tanks
etc.
The
operational
voltage
of
tools
and
lighting
equipment must not exceed 42 V AC.
Isolating transformers shall be provided by the Contractor for
producing the protective low voltage. A separate 42 V system will not be provided.

the

purpose

of

6.6/0.42

kV

Connection to neutral
The LV network shall be of the TN
auxiliary transformers are earthed directly.

type,

i.e.

the

LV neutrals

of

the

Neutralization (protective multiple earthling) is intended to prevent the persistence
of an excessively high contact potential on conductive parts of the installation
which do not form part of the actual operating circuit. For these purpose an earthed
middle conductor (N) (which becomes the neutral conductor N/PEN) is required.
An installation is considered to be neutralized when all parts of the installation
requiring protection arc connected to the neutral conductor or to a protective
conductor
(non-fused
earthed
wire)
which
is
itself
connected
to
the
neutral
conductor;

12
6

The neutral conductor must be earthed in the
distribution transformer, where it serves as the system earth.
The connection of the conductive non-live
of electrical apparatus) shall be carried out.

parts

vicinity

(e.g.

of

consumer

the

particular

enclosures,

local

frames

•in the case of conductor cross-sections up to 10 mm Cu via a protective
conductor to the neutral conductor
2

•in the case of conductor cross-sections from 10 mm Cu upward direct to the
neutral conductor ...
Symmetrically connected power consumers are to be connected to the neutral
conductor
(N/PEN),
using
a
four-wire
power
cable.
All
unsymmetrical
connected
power consumers (wall sockets, plug boxes, heating circuits etc.), where the cable
cross-section is less than 10 mm2, arc to be connected to a special protective
(earthing) conductor which is t<1 run alongside the neutral conductor. Because of
the clear demarcation between the neutral conductor, carrying operational current,
and the protective (earthing) conductor, which (under non-fault condition) carries
no current, NO connection between either N and PEN, or N and earth is
permissible beyond the point of separation of the neutral conductor (N/PEJ(J) into
PEN and N. Unsymmetrical connected consumers must be connected to four-wire
power cable for cable cross-sections equal to, or greater than 10 mm2.
The neutral conductor
conductors.
The
use
conductor is not permitted.

is
of

to be insulated in the same manner
constructional
parts
of
the
switchgear

as
as

the phase
a
neutral

Protective measures against installations over 1000 V
Protection against contact
At least the following measures arc to be taken for all parts that are 'live' when in
operation:






in general areas:


complete protection from all sides against contact,



protective devices may only be removed by means of tools.

in electrical rooms:


protection against contact with 'Jive' parts within reach of personnel,



protection against accidental contact outside the reach of personnel.

in enclosed electrical rooms:


protection against accidental contact.

The
above-mentioned
measures
for
protection
against
contact
are
also
to
be
applied to 'dead' parts of the plant where, in the case of a fault, a dangerous
contact potential might arise, however, where the parts must not be connected to
the protective earthing system for operational reasons.

12
7

Protection against contact voltages
Protective earthing is to be used as a safeguard against excessively high contact
potentials for conductive parts of the installation which do not form part of the
operational circuit. Here, all normally 'dead' parts equipment and apparatus shall
be earthed if it is possible for them to come into contact with 'live' parts as a result
of faults due to the occurrence of surface leakage paths, arcs or direct connections
to a 'Jive' part of the equipment.
In considering the dimensioning of the protective earthing system, the thermal
loading and voltages on the earlhing are decisive factor and these should be
based on the maximum possible earthing current, which can arise.
The earthing equipment and circuits must be of such proportions, as decided by
the Contractor, that the contact potential does not exceed the maximum
permissible value of 125 V:

0.6.17.8 Auxiliary equipment
Auxiliary switches
Where appropriate, each item of plant shall be equipped with all necessary
auxiliary switches, contactors and mechanism for indication, protection, metering,
control, interlocking, supervisory and other services. All auxiliary switches shall be
wired up to a terminal board on the fixed portion of the plant. whether they are in
use or not in the first instance.- .
Auxiliary switches associated with circuit breakers shall have additionally 2 N.O.
and 2 N.C. contacts for spare.
All auxiliary switches and mechanisms shall be mounted in approved accessible
positions clear of the operating mechanisms and shall be protected in an approved
manner. The contacts of all auxiliary switches shall be strong and shall have a
positive wiping action when closing.
Anti-condensation heaters
Each individual enclosure accommodating electrical equipment which is liable to
suffer from internal condensation due to atmospheric or load variations shall be
fitted with heating devices suitable for electrical operation at AC single phase, of
sufficient capacity to raise the internal temperature by about 5 °C above the
ambient temperature.
Heaters in motors shall be suitably fixed inside the windings.
Heaters in switchgear/ MCC cubicles. control cubicles. panels. desks. etc., shall be
controlled automatically by adjustable hygrostats (setting range about 50-100%
relative humidity).
The electrical apparatus so protected shall be designed so that the maximum
permitted rise in temperature is not exceeded if the heaters are energized while the
apparatus is in operation.

Heaters shall be connected to a suitable terminal box with main switch and
indicating lamp. They shall be placed in an accessible position. All equipment.
whether fitted with a heater or not. shall be provided with suitable drainage and be
free from pockets in which moisture can collect.

0.6.17.9 Requirements for local cubicles and local housings for e.g.
switchgear, control, measurement and signaling equipment
Steel-clad cubicles and enclosures with fixed, integral switchgear and apparatus
must be provided.
The switchgear cubicles must be partitioned off and incorporate a bus bar system,
the necessary instruments, control switches, switch panels of the individual switch
and apparatus chambers. The main bus bars are to be installed on the rear face,
topside of the switchgear cubicle in a lockable shuttered compartment.
Connections to switching devices, MCB's fuses etc. are to be made from these bus
bars. The lower part of the cubicle will house the terminal 'strips and connecting
blocks, the clamps for the cable terminals and if required parallel connection
copper straps for the connection of more than 2 cables in parallel. An adequate
number of ball studs must be provided within the switchgear cubicle suitable for
earthing the main and distribution bus bars as well as the switchgear itself by
means of portable earthing and short circuiting equipment (to be provided once per
switchgear panel row).
The space in the interior of the cubicles must be divided into a section with 'live'
parts, 'live' switching elements etc. and a section with control and measuring
equipment. The sections arc to be separated by reinforced sheet- steel. .
Care must be taken that in the event of arcing hot gases will not escape to the front
of the cubicles (the operational side).
Ammeters are to be provided on the cubicle front panel for the cubicle feeders and
the supply outlets for motors higher than 55 kW or motors of lower rating, but
particularly important for the process. A single voltmeter with 4-position voltmeter
changeover switch must be provided for measurements of bus bar voltage
between each phase and neutral. Measuring instruments should, in general, be
square in shape.
All cubicles, cabinets, panels, etc. shall be designed for an ambient temperature of
40°C (outside the enclosure) in non-air conditioned areas. Special precautions
shall be taken in the design of electronic devices for protection and control systems
housed in the cubicle in order to allow for these conditions.
Heating elements are to be provided generally in each local cubicle or cabinet and
shall be humidity controlled.
It must be possible to disconnect power supplies to the cabinets by means of
manually operated power circuit-breakers (MCB's).
For easy monitoring and a rapid grasp of the operational state, colored mimic
diagrams with the required switch position indicators, apparatus symbols and pilot
lamps must be provided in every case on main process cubicles and switchgear
cubicles. Lamp test facilities for all signed lamps connected shall be provided. All
cubicles shall be provided with the required earthing screws.

Plastic-insulated, stranded conductors must be used for wiring within the
switchgear cabinets, which must be numbered at each end with special tabs so
that change by mistake is impossible.
Preferably plug-in type auxiliary relays are to 'be used. Apparatus being sensitive
to impact must be protected against shock and vibration.
On completion of hand-over the cubicles must contain at least 15% of fully fitted
spare terminal capacity and 15% of spare space for the future installation of extra
equipment. It shall be possible to replace indicating lamps on the front panels of
cubicle feeders and motor-supply outlets with<?ut isolating the equipment
concerned. Further-more the control system must be designed in such a way that
lamps operate at less than their rated voltage in order to avoid their being
overheated.
Incoming and outgoing cables have to be fixed by suitable metallic cubic glands.

0.6.17.10 Local control points and level control cabinets
General
Any electrical consumer unit, which is not controlled automatically or from the
central control room, is to be fitted with a suitable local control cabinet. The
local control cabinets arc to be installed in the immediate vicinity of the motor
drive to be controlled.
Pump motors, which are level controlled locally, will be given an automatic and
manual control. The respective level control cabinets arc to be fitted in the
immediate vicinity of the pump motors, gauge glasses or level monitoring
instruments.
Local control points are to be provided for all MV motors and important LV
motors.
Construction requirements
In general local control cabinets and level control cabinets with plastic casings
or cast aluminum housings, resistant to impact, sand, light and seawater,
mounted on walls or hot-dip galvanized supporting constructions, are to be
provided. Hot-dip galvanized casings will be acceptable.
Protection class must be at least IP 55 (with additional measures if located
outdoors). The necessary earthing terminals must be provided for earthing
purposes.
The cabinets must be equipped with the necessary mini circuit breakers, fuses,
auxiliary relays, power contactors, terminal blocks and cable attachment
components.
For motors with pre-selection control (operation/stand-by) operatkin hours
counters are to be provided.
The stipulation of clause "Requirements. for local cubicles and local housing for
e.g. switch gear, control, measuring and signaling equipment" shall be applied
too.

In hazardous areas, the necessary explosion proof control cabinets and level
control equipment must be provided in accordance with IEC 79 and VDE
0165/170/171.
Local control points
The local control points are to be equipped as the minimum requirement with:




ON button


OFF button

Running lamp

FAULT LAMP

TRIP HEALTHY indication
Lamp test.
When two motors are installed, serving as operation and stand-by lIlIil, then in
addition to a double set of the above items, the following equipment has to he
installed as the minimum requiem:
•MOTOR 1 - MOTOR 2 (running motor/stand-by motor)prc-selection
switch,
•automatic transfer to the stand-by motor in case of failure of the running
motor.

Level controls
In the case of pump motors controlled by levels, in addition to thc level control
in each case the MANUAL - AUTOMATIC selector switch and the necessary
local points are to be fitted. Control of individual pump motors must be effected
as follows as the minimum requirement:






MANUAL - AUTOMATIC selector switch
level control with maximum and minimum contacts
low level contact on motor - OFF
bottom maximum contact on motor - ON
top maximum contact as warning to the central control room
•low-low level contact as pump dry-running protection and alarm signal
to the central control room
• local control point with ON and .OFF button, .running and fault lamp.
When two pump motors are installed for the same purpose the control is to
be effected as follows, as a minimum requirement:







MANUAL - AUTOMATIC selector switch
PUMP 1 - PUMP 2 (running pump / stand-by pump) pre-selection switch.
level control with three high level contacts:
first (I): high level contact for pre-selected ON
second (2): high level contact for alann signal to the central control room
low level contacts for pumps OFF
•low-low level contacts as pump dry-running protection and alarm signal to the
central control room .
•local control and lamps as listed above for local control cabinets, for each
motor.

0.6.17.11 Terminal boxes and terminal cabinets
In order to minimize the amount of cables and distribution of signals and to
centralize connections in the plant, terminal boxes or, wherever necessary, by
larger amounts of terminals, terminal cabinets shall be fitted on all the
necessary
• cable crossover terminal points
central collecting points for individual analog and binary signals and local
transmitters

signal collecting and distribution points for firc alarm, telephone, loudspeaker
and clock system
• central distribution points for local signals.


Terminal boxes and cabinets must at least have class of protection IP 54 and
must be equipped with the necessary terminal strips, cable glands and fittings
components for the connection of the cables ..
The necessary earthing terminals are to be provided for the earthing of the
boxes and cabinets.
In any area subject to the danger of explosion, the necessary explosion
protected technical boxes and cabinets are to be provided in accordance with
IEC 79 and VDE 0165/0170/0171.

0.6.17.12. Explosion proof equipment
According to the kind of fuels and gases used, the danger of explosions in
hazardous locations may be caused by ordinary electrical equipment.
Therefore, the installation in such locations shall generally be kept to a
minimum with said equipment designed or installed in compliance with the
latest issue of lEC Recommendation 79 and the appropriate Articles of the
American National Electrical Code (NEC) or the German VDE Standards
0165,0170,0171.
Hazardous locations shall be defined as follows:


Class 1, Div. 1 locations are those

(1) where hazardous concentrations of inflammable
continuously,
intermittently
periodically
under
operation and maintenance and with normal leakage,

vapors or gases exist
normal
conditions
of

and
(2) where the breakdown or faulty operation of process equipment could
release explosive concentrations of fuel and cause a simultaneous failure
of electrical equipment.

(1)

Class 1, Div. 2 are those
adjacent to Div. 1 locations
hazardous concentrations,

.
which

may

occasionally

be

reached

by

(2) where inflammable volatile liquids or gases are handled, processed, or
used, but where concentrations are not normally hazardous, because liquids
or gases are handled in close~ systems,
(3) where
hazardous
concentration
is
normally
prevented
by
positive
ventilation. These locations become only hazardous when the ventilation
systems fail.
The design features of electrical equipment and/or circuits to reach explosion
proof conditions shall be selected with due regard to the place of installations
and the kind of equipment.
The main principles shall be as follows:


Pressure and flame proof enclosure:
All parts which may ignite a hazardous atmosphere shall have an enclosure
of sufficient strength to withstand the maximum pressure caused by ignition
of the most inflammable mixture of the gas involved. All necessary joints of
such enclosure shall be provided with long fits (minimum 25 mm) and close
clearances (equal or smaller 0.6 mm) to cool the escaping flame and to
prevent flame propagation to the outside atmosphere.



Oil Immersion:
The parts capable of igniting inflammable or explosive mixtures shall be
immersed in oil to such an extent as to prevent- ignition of explosive
mixtures above the surface of oil by means of sparks or hot gases produced
under oil.



Increased Safety:
To obtain an increased degree of safety on electrical equipment special
measures should be taken to prevent unpennissible high temperatures,
sparks or arcs' inside and outside of the equipment on which they do not
occur under normal working operations.



Intrinsic Safety:
An electrical circuit or part of such a circuit shall be considered as intrinsically safe if neither during normal working operation nor under fault
conditions explosive mixtures are ignited by me~ arcs, sparks or any heat
generation.



Any other approved principle not mentioned above.
All explosion proof equipment shall be of approved 'design and must have
undergone type tests according to the appropriate standards. The selection of
such equipment with reference to design features and allocation to hazardous
groups shall be subject to approval by the Owner/Owner's Representative.

0.6.17.13 Keys and key cabinets
Key interlocked switches shall be provided with a Yale or other approved lock

for locking in the neutral position. A similar lock shall be provided for each
selector switch for Locking the switch in any of its positions.
Approved means shall be provided for locking the cubicle doors, live terminal
shutters, etc.
The locks or padlocks shall be coordinated for the different applications and
shall be supplied with three keys. A key cabinet at the end of each board shall
be provided for storing the keys of that board. All eyes shall have six master
keys to open any lock or padlock/supplied.
Each key shall have one identification label fixed above the key hanging
hook inside the cabinet.
The cabinet door keys shall be similar and shall be six in number.

0.6.17.14 Electric motors
General
All motors shall be of approved manufacture and shall comply with the
requirements of this Contract. They shall be complete with terminal boxes,
cable glands and, where specified, with heaters and monitoring instruments.
Motors of the same type must be fully interchangeable and shall comply as far
as applicable with IEC motor standard dimensions. All AC motors shall be of
the squirrel cage type provided with either deep slots or double squirrel cages.
All motors shall preferably be from the same manufacturer. The general
construction shall be stiff and rigid, no light metal alloy casings will be accepted
for motors above the size of 10 kW. All precautions shall be taken to avoid any
type of corrosion.
All motors shall be fitted with approved types of lifting hooks or eye bolts as
suitable.
Rating
The service voltages of the motors shall be as follows:




6600 V, AC 3-phase, 50 cps, for motors above 150 kW
400V, AC 3-phase, 50 cps, for motors up to and including 150 kW
220/110 V DC for all motors intended to work on the DC system.
The rating of each motor shall be adequate to meet the requirements of its
associated plant. The service factor, being the ratio of the installed motor
output to the required power at the shaft of the driven machine at its
expected maximum power demand, shall be applied as follows:
Power demand

Service factor

Up to 1 kW
More than 1 kW up to 10 kW
More than 10 kW up to 50 kW
More than 50 kW

1.3
1.2
1.15
1.1

0.6.17.14.1 High voltage motors
Constructive features:
The following constructive features shall apply:
a) Climatic protection provisions for mounting in the open in n humid and hot
climate. Insulation class F. During operation at rated power of the driven
machine, the motor insulation must only be stressed in accordance with the
requirements of class B insulation.
b) Motor parts made of iron internally and externally sandblasted and surfaceprotected.
c) Paint finish resistant to chemicals and seawater.
d) Bolts dichromate.
e) All joint faces and gaps sealed.
f) Anti-condensation heating to be switched into operation when the motor feed
circuit is in the 'off' position. Heater supply power 'on' indicting -lamps is to
be provided.
g) Special treatment of windings with resin impregnation plus immersion in
varnish.
h) Varnish-insulated laminations.
i) Pressboard material protected by varnishing.
j) Selection of special grade of sealing which are resistant to seawater.
k) Totally enclosed fan cooled type. For motor ratings the cooling air available
at the specific location has to be considered.
l) Condensation outlets to be provided at the lowest point in the housing.
Design and construction of the 111 Otors shall comply with IEC 34-1, 34-5 or VDE
0530 and DIN 40050.

Electric features
The following electric features shall apply:
a)
b)

c)
d)

e)

f)

g)

Motor rating to be at least 110% of the maximum required electric power
consumption of the driven machine.
Continuous delivery. of rated power at voltages of 90 - 110% of the" rated
voltage at any frequency between 95% - 105% within the thermal limits of
insulation class F.
Rated power output at ambient temperatures existing at the particular site of
installation and under continuous running conditions.
All motors shall be designed as 3-phase squirrel-cage motors suitable for
direct on line starting. It must be possible, With 100% residual voltage, to
switch them on to a large and stable power supply network without incurring
damage or deformation. The motors must still be capable of faultless running
up to speed with a voltage drop to 80% of rated voltage and rated loading.
Motor starting current must not exceed 5.5 times rated current (referred to
motor rating at 40°C ambient temp.). The voltage drop at starting must not
exceed 10% at the motor terminals.
From the cold state four consecutive starts up to full speed must be possible.
The second start must be possible immediately after the first start, the third
20 minutes after the second, the fourth 20 minutes after the third .•
A minimum frequency of starting cycles of 1000 per year must be
guaranteed.

h)

In general motors must be capable of running without overheating when
subjected to three consecutive starts within one hour after having run for an
extended period on a voltage of 95% nominal volt-age. Thereby the second
start must be possible immediately after the first start and the third 30
minutes after the second start. In individual cases where operation depends
on signals from pressure switches or other such sources, then a more severe
duty with respect to the frequency of starting cycles per hour shall be
necessary and the design of the motors must be carried out accordingly.

Protective features
The following protective\'e features shall apply:
i)

High
voltage
motors
must
be
fitted
determination of slot and bearing temperatures.

with

measuring

points

for

the

Six Pt 100 resistance thermometers (2 per phase, one each utilized for overtemperature warning, the other for over temperature trip) are to be provided
for slot temperature measurement, and a double thermocouple or resistance
thermometer
per
bearing
must
be
provided
for
bearing
temperature
measurement.
Each Pt 100 shall be connected, potential
connections
to
the
thermometer
as
well
cutouts shall be brought into separate terminal boxes.

free, to
as
the

a terminal strip. The
associated
over-voltage

j) Where motors have closed-cycle cooling. Temperature-measuring points

must be fitted in the cold air stream.
k) The winding temperature has to be detected with RTD's at high temperature

and alarm to be produced. at extra high temperature the motor to be tripped.
l) All motor gaps and joints between it and other units must be scaled ,
m) Earthing clamps at both sides of the stator have to be provided.

Other features
Terminal boxes
The main terminal boxes on the high voltage side shall be provided with a pressure
relief joint for the purpose of reducing the danger of an accident as a result of
short-circuits, and shall be fitted with a terminal block suitable for any desired type
of connection .
A permanently attached connection diagram
box cover. If motors are suitable for only
clearly indicated.

shall be mounted inside the terminal
one direction of rotation this shall be

Terminal boxes shall be totally enclosed and designed, to prevent the ingress of
moisture and dust (minimum IP 55). All joints shall be flanged with gaskets of
neoprene or similar material. The terminal box shall be scaled from the internal air
circuit of the motor.
Cable connecting boxes
sleeves and end caps.

must

be

longitudinally

divided

to

facilitate

filling

of

cable

In case lightning arresters for vacuum type switchgear controlled
foreseen, they shall be incorporated in the terminal box or in a separate box.
Inside the terminal
be foreseen.
The

opened

terminal

box

an

boxes

earthing

must

clamp

have

for

provision

connection

for

local

of

the

earthing

Bearings
Motors smaller than 2000 kW shall preferably be provided
gravity-fed type oil lubrication system with reservoir and oil breather.

motors

cable

to

with

be

a

are

to

shield

must

carried

constant

be

out.

level

Motors with roller bearings must be provided with a lubricator and lubricant supply
regulator fitted with solid brass cages that can be refilled while the machine is
running.
The bearings of the motors. must be free from stray bearing currents.
Where sleeve bearings are being used they shall be of the self forced lubricating
type. If forced lubrication is required it shall be arranged common to both -the
motor and the driven machine and provisions shall be made to ensure lubrication
during start-up and shut-down operations without the necessity to start an auxiliary
lube oil pump. Self-lubricated bearings shall be equipped with an easily accessible
lubrication pot with overflow pipe and oil collecting vessel.
All
bearings
shall
be
easily
controllable
during
operation
or
standstill
dismantling
the
bearings.
The
bearings
shall
further
be
protected
and
against dust penetration and oil leakage.

without
sealed

Connections, star-point terminal boxes, etc.
All motors must have the star-point connection brought out separately to terminals.
For all motors with a rating of 2000 kW or above a differential relay for winding
protection shall be provided and installed in the associated switchgear. In that case
the star-point connection shall be brought out separately to terminals.
The differential current transformers are to be designed to class 5P1 0 with a rating
matched to the protection system. The CTs shall be accommodated in the starpoint terminal box.
Coupling
The motor shaft halves of the couplings, finish-bored, balanced. and complete with
keyways are to be drawn on to the motor shaft and balanced out together with the
rotor. A coupling guard will be provided.
Running quality
The running quality must be within the classification of "good" according to the
VDE recommendations (VDl 2056 group D), i.e. the vibration velocity must be less
than or equal to 1.8 mm/s (rms.).

Cooling
Air cooling for the motors is the preferred method; where water-cooling is applied,
conditioned, treated water is to be used.
Motor air exchanger-circuits should be suitable for the prevailing atmospheric
conditions, i.e. ambient temperature,' content of humidity and salt in the air, etc.
are to be considered.
Where motors are installed outdoors, a weatherproof design shall be chosen. At
least one drilled hole shall be provided at the lowest point of the casing for draining
condensed moisture. All MV motors and LV motors of IEC size 132 and above
shall be equipped with automatically controlled heating elements for protection
against internal condensation of moisture during standstill periods.
Heaters of small motors shall be controlled by thermostats those of big motors by a
normally closed contact of the motor starter.
Motors shall have a closed internal cooling air circuit recooled by an external
cooling air circuit drawn, from the opposite side of the driving end. MV motors
installed in the turbine hall shrill be recooled by water taken. from the service water
s)'stem. The air/water coolers shall he arranged in such a way as to give free
access for cleaning purposes without dismantling them or the associated C.W.
pipes.
Motors installed outdoors and directly subjected to sun radiation shall be rated
such as not to overstep the maximum metal temperature of 85°C. Where
necessary such motors shall be provided with fabricated steel sun coverings.
Approved means shall be provided to protect motors installed vertically against
ingress of dirt, etc.
Reverse speed
If reverse running can occur in the case of equipment driven by a motor (e.g.
cooling water pump), the motor must be designed for maximum possible
reverse speed.
A reverse rotation alarm and starting-circuit interlock are to be provided to
ensure that the equipment can not be started while running in reverse.

0.6.17.14.2 Low voltage AC motors
Constructive features.
The same features as for high voltage motors shall apply. Anti-condensing
heating shall be provided for motors of 55 kW and above.
Electric features
All motors shall be designed as 3-phase squirrel-cage motors suitable for
direct on line starting.The motors must be capable of being-switched on to a large and stable

network and with phases in opposition.
The electric features a), b) and c) of high voltage motors also apply here.
Motors starting current must not exceed 7.0 times rated current (referred to
the motor rating and 40°C ambient temp.).
Protective features
An earthing clamp inside the terminal box has to be provided.
Other features
Cable Leads
All cable connecting boxes are to be designed to meet the requirements of IP 55 or
IP 58 protection class respectively.
The cable connecting boxes are to be installed easily accessible on the motor. The
connecting boxes .must be capable of being turned by 90 0 or 1800 and of being
opened up longitudinally. The connection boxes are to be filled with a terminal
block.
Bearings
Maintenance-free bearings are to be provided for motors up to 37 kW rating at
least. All motors utilizing maintenance-free bearings must be clearly and
permanently indicated as full. All other bearings must be provided with a lubricator
that can be used while the machine is running. Over-lubrication must be avoided
by means of a lubricant controlling device.
Motors installed in inaccessible locations must ha'{c lubrication connections piped
to accessible locations.
The motors are to be provided with roller bearings (i.e. groove ball or cylindrical
roller type). The motors must be free from stray bearing currents.
Cooling
The corresponding requirements of high voltage motors apply.
Shafts
Where not otherwise specified, motors must be filled with a free shaft end

0.6.17.14.3 Actuator drives
All actuators for valves, dampers etc are to be fitted with socket and plug of wellestablished make to IEC 309, VDE 0620, CEE 17 or equivalent for the power cable
connection. For the control cable connection separate socket and plug shall be
provided.
Self-cooling at respective ambient temp. Conditions is mandatory. Fan cooling is
not accepted

0.6.17.14.4 DC motors
As far as possible the use of DC motors is to be avoided and must be agreed by
the Engineer. The max. starting current must not exceed two times of the rated
motor current (referred to the motor rating at 40°C ambient temperature).
DC motors shall be capable of operating continuously under rated output
conditions at any voltage between 90% and 110% of the nominal voltage. Unless
otherwise approved the speed drop between no-load and full-load shall not exceed
10% of no-load speed. All DC motors shall operate with a fixed brush setting for all
toads.
Brush gear for DC motors shall be designed to ensure constant brush pressure.
Carbon brushes shall be provided which stand at least six months of operation
without replacement. Each brush shall be independently adjustable but shall not
require adjustment" throughout its life.
The brush holder shall not touch the commutator as the brushes wear and current
carrying through the pressure fingers will not be accepted.
A sufficient number of brushes, not less than two per pole, shall be fitted to ensure
that vibrations do not effect the commutation.
The minimum safe wearing depth of commutators shall not be less than 6 mm and
the minimum safe diameter shall be marked on them.

0.6.17.14.5 Painting
All motors, whether for outdoor or indoor installation, shall receive a coating of
paint which is resistant to sea water and corrosion.
All internal and external steel parts of the motors must be sand-blasted and
impregnated. Following this, a paint finish resistant to chemicals and seawater
must be applied. The' bolts used must be chromated at least.
0.6.17.14.6 Protection against explosion hazards
Low-voltage motors, which arc to be installed in areas exposed to the risk of
explosion, must comply with the rules laid down in VDE 0165/0170/0171 for
explosion-proof design in relation to the flash-point group classification for the
particular explosive mixture.

0.6.17.14.7 Frequency converters
General
On the basis of the requirements of the driven equipment, the Contractor will
design, supply, install and commission a complete, fully operative, variablespeed converter drive (frequency converter and motor, for motors up to 400
kW, for motors 400 kW and above in addition to the converter a converter
transformer wiII be provided) .
Converters made by reputable manufacturers are to be used.

Technical requirements
The design of the converter (maximum continuous
maximum shaft output required by the equipment assembly.

rating)

is

to

be

based

on

the

The converter should operate in two-quadrant mode.
Indirect converters with a constant indirect voltage are to be preferred to types
with
a constant indirect
current.
Power should be supplied to the converter
cubicles from below. If possible, the DC link reactors should be integrated in
the converter cubicles.
Maintenance
work
and
cable
front of the converter cubicles.

connections

to

rated.

speed
of
three-phase
be fully equipped for

asynchronous
motors
to
be
remote control and monitoring

a

to

be

provided

For motors with a rating lip to 400 kW the frequency
designed in at least a six-pulse circuit on both the line and motor sides.
For motors with a rating above 400 kW
12 pulse circuit supplied via converter transformer.

the

converter

should

that

the

the
must

are

such

from

The
converter
allows
adjusted steplessly. It
in the control room.

contactor

be

possible

and

power

are

be

input

and

sides

always

The terminals on the
cables can be connected.

An on-load disconnector
input of the converter.

output

must

at

the

converter

be

parallel

power

shall

designed

be

in

a

In the case of a current converter, the line rectifier is to take the form of a
line-commutated,
fully
controllable
three-phase
bridge.
A
self
commutated,
fully controllable three-phase bridge is to be provided for the inverter on the
load side.
In the case of a voltage converter, the line rectifier is to take the form of a
fully
controllable
three-phase
bridge.
A
self
com
mutated
three-phase
bridge
with turn-off thyristor branches is to be provided for the inverter on the load
side.
The line rectifiers are to
85% of the motor rated current.

be

designed

for

a

braking

current

which

is

at

least

The converter is to be disconnected if the voltage drops to less than 80% of
the rated voltage or if one or more phases of the line voltages are missed.
When the line voltage is restored, the converter is to be connected again
automatically,
providing
the
break
in
the
power
supply
did
not
last
longer
than
five
seconds.
The
plant
check
back
signals
(floating
change-over
contacts) must continue to be received during this period, while alarms are
to be suppressed. It must be possible for the converter to be connected at
.any
coasting-down
drive
speed
and
with
in-phase
voltages.
The
specified
frequency set point is to be resumed automatically.

If the voltage reduction or the power failure lasts for a long time, the drive mustremain switched off; in
this
case,
it
must
subsequently
only
be
possible
to
switch it on again either manually or by means of the higher order control.
The converters arc to be designed for 10% more than the maximum power
output required by the system. The purpose of regulating the converter is to
ensure that the indirect current and voltage remain within the permissible limits
during all control processes. This should apply both when the motor is started
up and when the speed is adjusted during operation.
All thyristors and diodes arc to be protected by
The fuses are to be arranged upstream of the semiconductors.
The reactors in the DC link
rise in the event of a malfunction.

should

Forced
ventilated
double fans).

are

converters

smooth

to

the

be

means

DC

current

equipped

Flow monitors (not air vanes) are to be used
control is to be provided for fan drives with a master drive.

of

with

to

semiconductor

and

limit

redundant"

monitor

the

fuses.

the

current

fans

fans.

(two

Positive

Converter transformers
The
converter
designed and
76.

transformers
the auxiliary

The transformers are
installed in protective
protection at least IP 21.

for
supplying
equipment to

the
be

frequency
converters
are
to
be
provided in accordance with IEC

to take the form of cast-resin transformers and arc to be
casings made of sheet steel, cooling method AN, type of

The
transformer
output
frequency converters.

shall

correspond

to

the

power

requirement

of

the

It should be possible to vary the high-voltage side within a range of 2 x ± 2.5%,
by means of reversible clamp connectors.
The connections on the high-voltage side have to be carried out using cables.
Bus
bar
connections
with
short-circuit
current converters on the 100\'-voltage side.
Suitable earthing studs
and short-circuiting) .

are

to

be

All
accessories
especially
sensors
arranged so that they are readily accessible.

protection

provided

and

for

arc

be

provided

maintenance

purposes

terminal

to

connections

The
windings
must
be
flame-retardant
and
self-extinguishing.
mixture
must
not
contain
any
flame-inhibiting
additives
which
vapors or gases either under the influence of secondary fires or
arc.

-

to

the

(earthing

must

be

The
cast-resin
develop
toxic
in the electric

A moisture-proof design will be provided. It will not be necessary to dry the.winding after shut-off periods.
The
protection
against
voltage
surges
and
short
circuits, the noise levels and the freedom from partial discharges up to twice
the rated voltage will be verified by means of type tests.
The
windings
are
to
be
protected
by
means
of
system, comprising the following minimum components:
• 3 PTC resistors (1 for each phase)
• 1 tripping unit with isolated change-over contacts for remote signaling
(alarms).

a

temperature

monitoring

The equipment types are to be agreed with the client in the event of an order
being placed.
All the lines belonging to the protection and
applied to a transfer terminal strip as individual signal lines.

monitoring

systems

are

to

be

Instrumentation and control
The instrumentation is subdivided into a local section in the converter cubicle
and into a "remote" section in the control room. All the measures necessary to
enable
the
drive
to
be
remote-controlled
and
remote-monitored
must
be
implemented, i.e. all the 24 V DC interposing relays which are required to
convert
the
on/off
commands
from
the
instrumentation
and
control
system,
signal transducers, etc.
A suitable automatic compensation facility is to be provided, to ensure that
the transfer between LOCAL mode and REMOTE mode is bump less in
both
directions.
The
emergency
shutdown
function
of
the
equipment
must
act on the converter directly, regardless of whether 'local' or 'remote' mode
is set.
Local instrumentation and control.
The following are to be provided as a minimum in the converter cubicle:
Controls

a)
b)
c)
d)

local/remote converter control (key-operated switch)
"on" and "off' converter controls
set point adjuster (speed)
incoming master switch, "on-off'
e) all the controls necessary for internal converter settings and adjustments,
as specified by the manufacturer
Indications, signals, monitoring

a) line voltage indicator
b) output frequency
c) output current
d) operating status

f)

signals, in accordance with the specifications of the
instrumentation
and
control
supplier,
though
at
least
"Ready",
"Drive
running and Zero and set speed reached "
e) motor temperature monitor - alarm Motor temperature monitor - shutdown
signals concerning internal operating states of the converter, in accor-















dance with the manufacturer's standards, though at least:
over temperature
line voltage monitoring
line under voltage
over current
control voltage monitoring
converter protection
fan monitoring
incoming air temperature
motor feeder interruption
motor feeder short circuit
earth fault
motor blocked
other faults
Remote control and remote indications
Account must be taken of the following types of remote control and indication in the control room, and suitable interposing relays, transducers and
switchgears are to be provided in the cubicle:

a)
b)
c)
d)
e)

converter "on/off' and "local/remote"
set point adjuster for speed (4 - 20 mA)
remote indication for speed as 0/4 - 20 mA standard signal
motor current as 4 - 20 mA standard signal
combined fault
f) remote indication of the set speed potentiometer as a 0/4 - 20 mA
standard signal
g) other controls and indications
All event signals and check back signals must be made available on the
terminal strip as floating change-over contacts
System perturbation
The perturbation caused by the voltage harmonics in the feeding three-phase
system, which are a result of the converter drives, must not exceed (he \
specified limit values, i.e. 5% for the 5th harmonic voltage, 4% for the 7th and
2% for each of the 11th and 13th. IEC 801.1 - 801.4 are also to be observed
in this connection. The system perturbations are to be curbed by means of
suitable
measures
if
necessary.
The
contractor
is
responsible
for
demonstrating conformance with the above-mentioned limit values.

0.6.17.14.8 Motor list
The motor list will be issued by the Contractor shall include all aggregates
driven by electrical -motors (except final control elements as control valves,
dampers, etc.) and shall contain at least the following technical data:






design speed of driven machine
kind of operation (continuous, intermittent, for start-up only)
type of motor construction, cooling, and protection
actual service factor
• electrical design data e.g. nameplate rating, rated voltage, rated speed,
rated current, power factor, efficiency, ratio of starting to rated current, ratio
of pull-out to rated torque
• other electrical data e.g. starting time at maximum opposing torque,
frequency of permissible starts (for motors above 10 kW only)
• driving end and non driving end bearings: manufacturer, type and type
number, size.

0.6.17.14.9 Tests
Each motor shall be factory tested and shall undergo a test at site. The
following tests shall be performed under full responsibility of the Contractor:
Workshop tests







measurements of winding resistances (1)
no-load and short-circuit measurements (*)
efficiency measurement (type test)
heat test run (type test)
dielectric test (*)
measurement of insulating resistance (*)



over speed test (*)
(*) may be type tests for motors of final control elements
At motors rated 100 kW or higher in addition:






measurement of motor vibrations
measurement of starting current and torque (type test)
air gap measurement (type test)
measurement of noise level (type test).
Tests at site



measurement of insulation resistance



measurement of motor vibrations.
At motors rated 100 kW or higher in addition:



1


measurement of starting period.

item and code no.location
manufacturer and catalogue no. of motor and driven machine

0.6.17.15 Labels
General
The proposed material of the labels, the size, the exact label inscriptions as well as
proposals for the arrangement of the labels shall be submitted to the Engineer for
approval. Where applicable, Bengali designations shall appear above or to the

right of the English designation. The Bengali translations
readable Bengali and samples shall be submitted beforehand for approval.

and

writings

shall

,be

Equipment labels and instruction plates
Labels
written
in
English
shall
be
provided
for
all
instruments,
relays,
control
switches,
push
buttons,
indication
lights,
breakers,
etc.
In
case
of
instruments,
instrument switches and control switches, where the function is indicated on the
dial plate or the switch escutcheon plate, no label is required. The label shall be
fixed close to the instrument in such a way that easy identification is possible.
Fixing on the dial glass of instruments will not be accepted. The wording shall
conform to the wording used in engineering documents and shall be submitted for
approval to the Owner/Engineer.
All
construction
units
shall
be
identified
by
their
plant
identification
number.
Cubicles and similar units shall also bear this identification number on the rear side
if rear access is maintained.
All equipment inside cubicles, panels, boxes etc., shall
their item number. This number shall be the same as
documents (wiring diagrams, equipment list, etc.).
Instruction plates showing in
cautions for maintenance shall
electrical switchgear.

be properly labeled with
indicated in the pertaining

l3angali and English the sequence
be fitted on the inside of the front

diagrams or
door of the

Each separate construction unit (cubicle, panel desk, box, etc.) shall be provided
with top mounted labels made of anodized aluminum with black inscriptions giving
the overall designation in Bengali and in English.
Warning labels
Warning labels shall be made of synthetic resin with letters engraved in Bengali
and English.
For indoor circuit breakers, starters, etc., transparent plastic material with suitably
contrasting colors and engraved lettering shall be provided.
L V switchgear shall have yellow labels with 5 cm black letters reading "MAINS
400 VOLTS" .
MV switchgear and transformers shall have red labels with 7.5 cm white fetters
reading "DANGER 400 V or 6600 VOLTS".
All switch room door labels (lettering as before) shall be as follows:
Labels for conduits, etc.
The material shall be non-corrodible and the inscription be done with 4 mm
high letters/ciphers.
Labels for cables
Each cable when completely erected shall have permanently attached to it at
each end and at intermediate positions as may be considered necessary by the
Owner/Engineer, non-corrodible labels detailing identification number of the

cable, voltage, and conductor size.
The cable identification numbers shall comply with those of the cable schedule.
All cables in cable pits and at entry to building blocks shall be labeled utilizing
the aforementioned type of label.
Nameplates
Equipment (machines, transformers, etc.) nameplates shall be either of the
enameled type or be of stainless steel covered after stamping with a transparent paint. .

0.6.18 Instrumentation and control
0.6.18.1 Measuring units
All instruments shall be calibrated and inscribed in the metric system. No
other measuring units than the following ones shall be used for the
measured variables.



bar for pressures of steam, water, oil, compressed air and high pressure gas
mbar
for combustion air, flue gas and low
pressure gas
°C
for temperatures
mm or m

for levels

^S cm

for conductivity

rpm
%
Nm3/h

for rotating speeds
for positions
for combustion air and gas flows

t/h

for steam and water flow

% Vol.

for flue gas analys6s

^m or mm/sec

for eccentricity and vibrations

mm

for differential and absolute expansions

cps

for frequency

A,kA

for currents

V,kV

for voltage

MW, kW

for active power

MVAr, kVAr

for reactive power

Wh, kWh

for active energy

V Arh, kVArh

for reactive energy

0.6.18.2 Sizes of indicators, recorders, etc.

-The indicating instruments and
recorders shall have the following
or similar sizes
Indicator on local control panels
and
MV and LV switch-gears
-

-

Indicators on vertical section of
control desks < in control room
and on rectifier or converter
panels

96 x 48 mm or
96 x 96 mm

Indicators on horizontal part of
control
desks in control room

48 x48 mm

Indicators
on
control
control room
72 x 72 mm or 144 x 72 mm or

- Recorders:

144 x 72 mm or
72 x 72 mm

panels

144
x
144
recorders)
288 x 288 mm (foI' 12-point
recorders)

mm

in

144 x 144 mm or
96 x 48 mm
mimic diagrams)
(for

line

(when

incorporated

and

- Pressure gauges and other dial
type instruments (locally):
The control switches, adjusters, etc., on the panels and desks shall harmonize with the above mentioned indicator sizes.

0.6.18.3 Protection and safety interlocks
To protect individual units or parts of the power plant, interlocks are to be
formed in accordance with process criteria, which can be either active or
passive depending on their functions.

6-point

in

Active interlocks shall automatically disconnect units or parts of the powerplant before they
reach a critical operating condition or shall start certain
units (e.g. stand-by) in order to avoid a critical operating condition. In
addition, such dangerous conditions must be immediately indicated to the
operating personnel by means of an alarm.
Passive interlocks are intended to prevent operational errors or wrong
commands from being carried out in the event of selective faults in the
automatic control.
Active and passive interlocks must not be capable of being switched off
operationally from the central control room. All protections have to work fully
automatically and independent of the operator and always have to be
effective for all procedures (manual, partial automatic, fully automatic).
After a stop or close action by protection, the restart of the equipment shall
be possible only after the fault is rectified and the protection signal is reset.
Simple cancellation of protection signal by start command shall not be
possible. The protection action and the operator reset shall be recorded by
the DCS.

0.6.18.4 Special local conditions
Due to the high humidity special measures shall be considered for the
I&C equipment.


All local indicators shall be of stainless steel.




All impulse/sampling piping shall he of non corrosive type (e.g. stainless
steel. copper. plastic).
• All copper pipes - except installed inside buildings - shall be protected with
an external plastic sheet.
All external screws of transmitters etc shall be of non-corrosive material.


All secondary shut off valves equalization valves and drain blow-off valves
shall be of the non-corrosive type.
All metallic instrument piping must be protected with corrosion protecting
painting.
All I&C equipment exposed to sun must be protected against direct sun
radiation. This may be done by sun roofs. protection casings. etc.
All multicore I&C cables (with more than 7 cores) outside the buildings shall
be covered completely by means of closed cable trays flexible conduits. etc.
The individual cables from the
terminal
preferably 160 mm diameter
boxes to the instruments shall be
protected as far as practicable.
The
cable
direct
at
the
instruments
connection
must
only
be
protected, if
exposed to direct sun radiation





0.6.18.5 Tests
The
single
components
and
pre-erected
assemblies
shall
undergo
functional
and
routine
tests
in
the
Contractor's
or
Sub-Contractor's
workshop.
The
ready
mounted
control
and
supervisory
system
shall
undergo functional tests on site prior to pulling the plant under steam.
These tests shall take place in the presence of the. Owner's and Engineer's

representatives. Besides. all equipment shall be tested in compliance with
the prevailing lEC standards and recommendations.
The Contractor shall submit to the Engineer acceptance test certificates on
ail tests carried out in the workshops. The results of site tests shall be laid
down in reports to be written by the Contractor and signed by the Engineer.
Calibration tests arc to be witnessed on all important pressure gauges and
other instruments as required by the Engineer.

0.6.18.6 Field equipment
0.6.18.6.1 Measuring systems/transmitters

^

Only electric measuring signals of 4-20 mA shall be transmitted to the DCS.
Generally 2-wire transmitters shall be used. If for some special purposes (e.g.
analyzers) 230 V AC power supply is required. the output circuit shall be isolated.
As far as possible. all transmitters shall be of the SMART-type. This applies also to
field-mounted temperature transmitters.
Thus. only sensors, transmitters and converters with electrical output shall be
provided. The output signal of transmitters shall be linear and over a wide range
independent of the burden in the output circuit.
Transmitters with accuracy class 0.5 or better must be used. The repeatability shall
be within a range of ± 0.1 % of full span.
The removal of connected devices must not open the transmitter output circuit or
cause malfunction of this circuit. In the case of failure and return of the supply
voltage within a measuring circuit. no false signals endangering the system shall
be issued. All transmitters shall be individually fused.
The components shall quickly respond to any changes of the measured variables.
Measuring errors shall be as low as practicable. Measuring ranges of indicators,
transmitters, etc. shall be selected in such way that the rated value of the variable
covers approximately 75% of the span.
Diaphragm seals shall be provided to serve as a barrier for corrosive process
fluids, slurries or highly viscous oils. The seal shall be of the flanged type, suitable
for the same conditions as those for the transmitter. The material selection shall be
according to the requirements of the fluids to be measured. The seal shall be
provided with a flushing connection.
Transmitters to be used in hazardous areas shall be explosion proof. Suitable
intrinsically safe circuits arc to be provided in accordance with DIN EN 50020.
All transmitters potentially subjected lo vacuum shall be capable of withstanding
100% vacuum without damage.

No stress shall be imposed through the connections between process equipment
and the transmitter; As far as possible. the transmitters shall be grouped togetherinto
enclosed racks or panels for easy access. Sunshades shall be provided for all
outdoor panels
Individually installed transmitters shall have their own weather proof enclosure of
robust construction "nu be suitable for the proposed environment. All field
equipment terminals shall be wired to a terminal box using screwed connections.
Transmitters shall be provided with all necessary isolating, vent and blow down
valves and facilities shall be provided for the connection of test instruments at the
input and output of each transmitter, to enable calibration to be carried out.
All control, measuring and supervisory equipment (including actuators) related to
the explosion-prone areas shall be of explosion proof, e.g. intrinsically safe design.
0.6.18.6.2 Flow measurements
The primary elements of flow meters shall be standard orifices and standard
nozzles unless otherwise specified.
Their design and performance shall be in accordance with the before mentioned
Standards.
The throats of flow metering nozzles and orifices shall properly be protected
against erosion by means of stellite lining or equivalent means. In case of Reynold
numbers below 100,000 quadrant nozzles or double tapered orifices shall be
provided.
Primary elements such as orifices or nozzles located in steam or high pressure
feed water pipes shall be of the weld-in type. Material, dimensions and installation
of orifices, nozzles and tapping points etc. shall be in accordance with the
specification for the pipes in which they are installed.
Isolating valves shall be provided at the tapping points of the orifices/ nozzles. In
the case of steam flow measurements condensing vessels (steam traps) shall be
provided between the tapping point and the isolating valve.
In case of flow measurements for fluids with pressures higher than 25 bar double
shut-off tapping valves shall be installed. The design and arrangement of tapping
point, piping and valves should be according to VDI/VDE rules 3512 Bl.1 or
equivalent standards.
The material and dimensions of the piping shall conform to those laid down for the
piping concerned. The welds shall be executed in such a manner as to avoid
turbulence them can affect measurement.
In order to achieve exact installation, the vendor supplying the orifice plate or
nozzle for high pressure pipes shall install the orifice plate or nozzle in its own
works in a section of pipe of about 3.5 times the pipe diameter (1.0 x Nil in the
outlet, 2.5 x Nil in the inlet). For orifice plates or nozzles installed in pipes with a
nominal bore smaller than 80 mm, complete meter runs shall be supplied.
Orifice plates and nozzles shall be manufactured of ANSI 316 Stainless Steel
unless specified otherwise.
Orifice plates shall be sized for a d/D ratio not less than 0.20 and not greater than

0.70. Higher other than lower d/D ratio are preferred to
All sizing calculations shall be submitted to the Engineer for approval.

minimi7.c

line

restrictions.

Tags on orifice plates shall be stamped with the basic design information (i.e. flow
rate, pressure and temperature of the passing fluid, the orifice diameter and the
pressure differential generated).
Venturi tubes shall only
permanent pressure losses.

be

considered

when

operating

economy

Rectangular venturi tubes may be considered where other
are impossible or impractical (e.g. in large rectangular air duct of boilers).

requires

measuring

low

devices

For flow measurements in LP-systems e.g. water or condensate, orifice plate
installation using slip-on orifice flanges shall be provided. All orilicc plates for
installation
between
flanges
shall
have
their
own
tapings
for
differential
pressure measurements incorporated in the plate. simple orifice plates with the
tapings situated in the pipe arc not allowed. The flow direction shall be
consistently marked on the orifice or nozzle by means of an arrow.
Steam,
gas
and
temperature
and/or
flow signal.

air
flow
pressure

measurements
at
measuring
points
should
be
provided
with
automatic

with
variable
correction
of

All flow transmitters shall begin to measure correctly at a rate of flow of at least
5% of the measuring range. The error limit shall be limited to ± I % f~ a rate of
flow higher than 10%. The error of the primary elements is not included in this
accuracy.
The root extraction
the transmitters.

of

flow

measurements

shall

be

effected

electrically

within

All flow transmitters shall be in accordance with Chapter B06.18.6.1
Special conditions may dictate the use of devices such as:
• venturi tubes for low pressure gases
• pilot tubes such as Annubar
For the measurement of fuel oil flow, turbine type meters or positive
displacement meters shall be used.
Magnetic and ultrasonic flow meters may be used under
but prior to their" use agreement must be obtained from the Engineer.

special

circumstances

• Arrangement of flow measurements
The arrangement of the throttling devices, e.g. the straight length upstream and
downstream from the throttling device shall be according to Standard DIN EN
ISO 5167-1. Bends shall be at a sufficient distance upstream from the throttling
device, particularly when large orifice ratios are used.
When the requirements of the Standards cannot be fully complied
cases, then, as an exception, an uninterrupted pipe run of at least lOx Diameter

within

some

(D) length should be provided, with 8 D located upstream, and 2 D downstream
from the measuring point. The said exception is subject to special approval by
the Engineer.

0.6.18.6.3 Temperature measurements
All temperature measurements
wells, where applicable.

shall

generally be

carried

out

with

protective

Wells of the screw-in (NPT-connection) put-in type shall be restricted to
measuring points for lubrication oil, dematerialized water, air, gas, cooling
water and flue gas, and to such measuring points where welding is 1I0t
suitable, e.g. at cast-iron parts. All other protective wells shall be welded to the
pipe. Thermometer wells shall be covered by screwed caps for protection
during transportation and creation.
Gastight ceramic inside tubes shall be provided in addition
protective tube for temperatures higher than 650°C.

to the

outside

Resistance and thermocouple thermometers shall be equipped with weather
proof connection heads. These thermometers shall be arranged in such a way
that the connection heads do not become warmer than 100°C, and that the
measuring inserts are easily exchangeable.
The temperature sensors shall be selected in such a way, that only a small
number of different spare inserts is required.
Resistance thermometers shall generally be of type Pt 100 and shall not be
applied for measuring values above 450°C approximately Double resistance
thermometers (with two resistors in one insert) should be used.
For resistance thermometers 3 wire circuits shall be applied principally.
Depending on the operating temperature the following thermocoup2es shall be
used:



Fe-Constantan for temperatures up to

700°C



NiCr-Ni

for temperatures up to

950°C



Pt Rh-Pt

for temperatures higher than 950°C

Thermocouples shall be connected to reference junction devices by means of
suitable compensation leads. The wiring from the reference junction boxes to
the receiver may be normal cable (multicore cable).
Locally mounted temperature transmitters shall be used for remote indication
and functions. Head mounted temperature transmitters may also be used. All
temperature transmitters shall be in accordance with Chapter B0.6.18.6.1.
Where more than one temperature measurement e.g. recording. indication.
automatic control is to be made at one location. individual protective wells with
sensors shall be provided at the common place of measurement. Protective
wells for unoccupied test measuring points and shall be arranged with the
opening inclined downwards wherever possible and shall be provided with a
screw-on protection cover.

The use of dial type contact thermometers shall be restricted to bearing metal
only. In all other cases thermocouples or resistance thermometers and
electronic limit switches shall be used. Glass thermometers or similar will not
be accepted as contact thermometers.
Insofar as local conditions or extreme temperature do not require otherwise.
Screw-in immersion wells for exhaust gas and air shall meet the following
requirements:


nominal length not less than 0.5 m

the attachment of the well in the wall of the exhaust gas channel or air duct
must be gas-proof.
For the measurement of temperature of other media the following requirements
shall be observed:
For all pipe work a minimum immersion depth of 55 mm in the internal pipeline
cross-section and a minimum distance of 15 mm from the opposite pipe wall
must be provided. If the diameter of the pipeline does not allow the
thermometer to be inserted perpendicular to the pipe axis while still maintaining
the above mentioned measurements another solution must be found in
cooperation with the Engineer.
When determining the lengths of the insertion
insulation thickness is 10 be taken into consideration.

and

connecting

tubes

the

0.6.18.6.4 . Pressure measurements
Pressure gauges shall be shock and vibration proof (preferably by filling with
glycerin). They shall be made as far as possible of stainless steel. Pressure
gauges for steam and gas shall have safety properties according to DIN 16006
or equivalent.
Over ranging the measured pressure shall not deteriorate the pressure gauge
nor affect its calibration. The pressure gauges shall be equipped with a radial
connecting stud, to allow the mounting on a gauge holder.
Pressure gauges with
pressure transmitter.

potentiometers

will

not

be

accepted

for

use

as

a

Pressures to be remotely indicated, recorded or used for automatic control loop
inputs shall be measured by means of pressure transmitters (refer to Chapter
B0.6.18.6.1).
Each gauge, pressure switch and transmitter for absolute or differential
pressure shall be equipped with a pressure gauge isolating valve including a
test connection of the screwed type M20 x 1.5 mm. This isolating valve shall be
located directly at each gauge, pressure switch or transmitter. If the gauge or
transmitter serves for control, interlocking, or alarm purposes, the shut-off valve
shall have separate shut-off devices for both the instrument and the test
connection.
Pressure transmitters may not be directly mounted on the pressure tapping
point. They shall be mounted apart from the tapping point. Whenever possible,

transmitters shall group wise be combined
area). In case of flowing substances, the
regions of undisturbed flow.

on racks or
tapping point

The
design
and
arrangement
of
tapping
points,
according to VDI/VDE rules 3512 Bl 3 or equivalent standards.

piping

in cubicles (in open
shall be selected in
and

valves

shall

be

Pressure measurement tapping points shall generally be in accordance with the
specification for the pipeline in which they are installed and shall be equipped
with one, and, for high pressure installations (> 25 bar) two, isolating valves
arranged directly at the tapping point and having a nominal bore of at least 15
mm (1/2"). Excluded from this stipulation are measuring points for vacuum and
measuring points for combustion air and exhaust gas.
Piping shall be of approved quality and sized for the particular service. In all
cases the pipe size shall be chosen to ensure strength and freedom from
blockage. Instrument impulse pipe work shall be manufactured from a suitable
grade of stainless steel to the approval of the Engineer.
For
gas
measurements
the
pressure
tapping
point;
if
this
arrangement
is
down valves shall be installed.
For
liquid
measurements
tapping
point,
gas
traps
impossible.

the
pressure
and
blow-off

sensor
shall
be
arranged
impossible
condensate
craps
sensor
valves

shall
shall

be
be

For steam pressure measurements the connecting tube between tapping
point and pressure gauge or transmitter shall incorporate a condensing
syphon.
The liquid columns in the connecting tubes shall be considered in the
calibration of the pressure gauges and transmitters.
Open blow down/drain connections shall not be arranged within panels and
local equipment. Instead it shall be led to a drain external to the panel.
All valves shall be installed so that they are accessible for maintenance
from a floor or permanent structure landing.
Tapping points for pressure gauges or transmitters to be installed in heavy
fuel oil systems are to be provided with seal pots or with separating diaphragms.
In addition to the above requirements, special valve block equipment shall
be provided, where differential pressure is. to be measured.
The blow-off valves must be separated from the valve block, if test connections are required.

arranged
mounted

above
and

the
blow

below
the
if
this
is

0.6.18.6.5 Analyses measurements
0.6.18.6.5.1 Analyses of steam and water
Conductivity electrodes, pH-electrodes, and other sensors for analysis may only
be built directly into pipes if the medium pressure is below 25 bar. In all other
cases sampling devices shall be provided.
Sampling devices and analyzers for steam and water shall be centralized by
groups on sampling racks. These devices shall simultaneously serve for local
supervision and manual sample taking as well.
Furthermore, these sampling devices shall operate in a way that first cooling and
then throttling of the medium takes place.
The sampling system shall include but not be limited to all' probes, valves, filters,
coolers, drainage facilities, flow regulators, flow meters, piping and pumps as
necessary, to give the analyzer a representative and suitably conditioned
sample.
Each automatic analysis sampling point shall be provided with a manual
sampling point to permit a sample to be easily taken. Manual sampling shall not
interrupt automatic sampling. All sampling lines shall be run to common sampling
racks on which shall be fitted all the analysis associated equipment.
For convenient manual sample taking the sampling devices shall be equipped
with funnels with inherent screens to locate the sample bottles upon.
The sample racks shall be situated in such a way as to obtain minimum length of
the tubes from the sample tapping points to the racks. These tubes shall be of
nickel or equivalent material.
Whenever required for a useful analysis measurement, the installed sampling
device shall include a cation exchanger. The cation filters shall have visible colour
indicators to show when they have to be regenerated.
For all analyzers temperature compensation shall
temperature sensor being an integral part of the probe.

be

provided,

with

the

Chlorine residual monitors and hypochlorite concentration meters shall preferably
be able to measure high and low concentrations: Measurement of hypochlorite
concentration shall not be affected by the presence of other oxidizing components
in the sample.
Individual or multiple prefabricated analyser installations shall be used to reduce
site installation work. This prefabrication shall include sample conditioners,
analyzers, air and electrical distribution, cooling water distribution or coolant
circulating system all piped and wired on a common frame. Interconnecting pipe
work and accessories shall be of stainless steel. The arrangement shall permit
testing of the entire assembly before dispatch to site and shall be arranged for
convenient removal from on-line operation to facilitate routine maintenance and
calibration.

0.6.18.6.5.2 Analysis of exhaust gas
The analysis of 02, CO, NOx, SOx and dust in the exhaust gas shall be
performed for each unit by appropriate analyzers of proven type.
The equipment shall be constructed for operation in dusty and humid
environments at high ambient and exhaust gas temperatures. The use of
equipment capable of multi-parameter measurement shall be considered.
The reliability and response time of the 02-analyzer shall be of the quality'
required for closed-loop control. A zirconium oxide measuring cell shall be
used. Maintenance shall not be more than once a week.
Analyzers provided shall. have auto-calibration for zero and span as well as
self-diagnostic functions.
The sampling probes shall preferably be vertically installed on the top of
horizontal exhaust gas ducts, in order to avoid blockages.
In order to keep the sampling lays to acceptable limits the analyzers shall be
located close to their sample take-off point, so that easy access to the sample
take-off point and to the analyzers shall be provided for maintenance.
The exhaust gas sampling lines shall be heated to prevent condensation and
shall not form a siphon in the case where condensate may be collected
during heater failure. Condensate drainage facilities shall be provided the
analyzers.
Generally, the analyzers and the sampling probe equipment shall be mounted
in an air-conditioned room or container.
Monitoring and supervision of emission
values, etc.) shall be done in the DCS.

measurements

(half-hour

mean

Power failure and system failures of analyzers shall be monitored in the DCS
by a group alarm.
Adequate measures shall be taken to eliminate dirt from the sampled gas
before it reaches the analyzer. Besides; effective measures shall be taken to
avoid-sulfuric corrosion within the samplers/or analyzers.- .
The analyzers shall be a type which does not continuously consume reference gases (like hydrogen).
The analyzers shall fulfill the following requirements:

maximum

long-time drift (zero):

± 2% of full scale deflection per week

long- time drift (sensitivity): ± 2% of the set point per week
influence of temperature ± 2% of full scale deflection per 100e

20 sec. per 90% of full deflection
linearity:

±3% of full scale deflection

0.6.18.6.6 Level measurements
The remote measurements for the liquid level in the boiler drums and banks
with a steam cushion of pressure above atmosphere shall be of the hydrostatic principle by means of a differential pressure transmitter.
For liquid measurements in condensers and tanks with a steam cushion of
pressure below atmosphere level transmitters of displacement type or of
differential pressure type with isolating membranes shall be used. The
membranes shall be installed close to the condenser or tank.
Where detection of discrete levels is required, the simple float operated switch
should be used, however each switch shall have snap action with limited
hysteresis to prevent contact bounce caused by small fluctuations in level.
Switches used for level detection shall provide facilities for testing the
mechanical and electrical operation of the switch without its removal from the
process. Isolation by means or shut-off valve will be allowable during testing.
POI' measurement of large storage tanks, the load indication and transmitting
mechanism shall be located at the base of the tank.
The transmitters shall be as specified under Chapter B0.6.18.6.1.
For special applications such as chemical tanks, techniques such as ultrasonic, capacitance probes, etc. should be considered.
For measurements where a reference leg of process fluid is used. the design
of the system shall ensure that the reference leg is fully maintained at its
prescribed height during all conditions of process level change and changes in
process conditions and the density of the reference leg docs not vary from that
of the process fluid due to. temperature changes or other reasons.
All measurement transmitters for differential pressure shall be provided with:

a) shut-off valves to be arranged directly at the condensing vessels and
active pressure tapping points

b) valve blocks enabling the transmitter to be isolated from the active
pressure and enabling the transmitter zero point to be checked

c) separate blow-off valves for cleaning the active pressure tubes.
The aforementioned valves shall be of the weld-in type.
Where a standpipe exists, the level transmitters or level switches must be
connected to the standpipe by means of shut-off valves, so that the units can
be replaced easily in service.

indication time constant:

Local level indicators of big tanks
shall be equipped with a scale length
of
full
height of the tank. Locally mounted water level indicators shall be of bicolortype equipped
with
electric
illumination,
working
in
such a
way that
the
water
level is clearly readable as a column over the complete measuring range.
Level indicators showing the level only as a point will not be accepted.
The indicating range of local level indicators shall cover all switching points of
level switches mounted on the tank or similar as a minimum requirement.
On all forms of measurement all parts of the switch, transmitter, etc. in contact
with the process fluid shall be made of material compatible with the process
fluid, Stainless steel shall normally be used for all corrosive duties

0.6.18.6.7 Electrical measurements.
0.6.18.6.7.1 Electrical equipment, instrument and meters
All indicating instruments shall comply with IEC-51 and shall have a Class Index
between 1.0 and 5.0 depending upon scale length. They shall be of approved
type, make and size and flush mounted with square bezels and square or
rectangular faces. The cases of instrument and meters shall be dust and
moisture proof and suitable for use in a tropical climate.
Instrument scales shall be clearly divided and indelibly marked.
Where ammeters are provided for indication of motor currents they shall be
supplied with overload scales indicating the six times full load current.
The dials of such ammeters shall include a red line to indicate the full load
current of the motor.
Instrument pointers shall be of low parallax type and means shall be provided for
zero adjustments without dismantling. They shall be as arranged that the normal
working indication is between 50 and 75% of full-scale deflection.
All integrating meters shall be flush mounted and shall comply with the relevant
parts of IEC-521 for MWh meters, with dial type registers. Approved test terminal
blocks of the three-phase type shall be provided
for connecting in circuit with each meter a portable testing meter.
The meters shall be able to record min. 10000 hours and shall be suitable for
unsymmetrically loaded phases.
For generator circuits all export only and import only
maximum demand indicators of class 0.5. They shall
transmitters to operate MWh electronic summators
indicators. All maximum demand indicators shall have
period.

MWh meters shall have
be fitted with inductive
with maximum demand
a 30 minutes resetting

All other meters for acceptance testing shall be not less than class 1.0.

All instruments and apparatus shall be capable of carrying continuously 120% of
their full load current without undue heating. They shall not be damaged by the
passage of fault currents within the rating of the associated switchgear throughthe
primaries of their corresponding instrument transformers.
All voltage circuits to instruments shall be protected by a fuse in each unearthed
phase of the circuit placed as close as practicable to the main connections. All
power factor indicators shall have the star point of their current coils brought out
to a separate terminal which shall be connected to the star point of the
instrument current transformer secondary windings.
The scales of all direct current instruments and of all alternating current indicating
watt meters shall be arranged so that the instruments will read 10% of the full
scale reading below zero and this part of the scale shall be marked in red.
In duo-directional circuits centre zero instruments shall be used.
Watt meters and Var meters shall include the limits for inductive and capacitive
power factor.
When more than one measured value will be indicated on the same instrument,
the measuring point selector switch will be provided next to the instrument and
will be engraved with a legend of the measuring points.
0.6.18.6.7.2 Transducers
General
Transducer for electrical power metering shall comply with IEC-688-1.
All transducers shall be provided with a nameplate, indelibly marked with the
following information:







name of manufacturer
manufacturer's type reference
serial number
rate input voltage and current, as appropriate
DC output current
overall ratio (e.g. Watts/mA).
The type of transducers selected shall be suitable for use in digital instrumentation schemes and the outputs of all transducers shall have a linear
relationship with the measured quantity. Transducers shall be self-powered,
where possible, or powered from the RTU battery power supply.
Each current input shall be capable of carrying 200% rated current continuously
and shall withstand 10 times rated current for 5 seconds without damage. The
output shall be accurate up to 120% rated output. In addition, transducer inputs
shall withstand 30 times rated input current on each range for 3 seconds without
damage.
Transducers shall withstand for one hour, without damage, a short circuit on the
output terminals when the input circuits arc carrying rated voltage and current.
The error in transducer output shall be not more than ± 0.5% of full rated output
over as great a part of the output range as possible. For all inputs, the output

error shall not exceed ± 0.2% due to ± 10% voltage variation in the

voltage circuit
frequency.

input

nor

exceed

±

The root-mean square ripple current
current and shall preferably be much less.

0.5%

shall

due

not

to

a

exceed

±

10%

5%

of

change

the

in

the

maximum

input

signal

The response time to reach and remain above 80% of the final steady value for a
step change in input from zero to a value equal to full rated output shall not
exceed 1 second.
Adjusters shall be provided to allow adjustment of the output current to be made
to
compensate
for
errors
of
primary
circuit
transformers.
Adjustment
may
be
continuous or in fixed steps. A range of ± 2% adjustment in the output current
shall be provided.
Power transducers
For
the
measurement
of
three-phase
balanced
power
flows;
Watt/Var
transducers designed for reversible real and reactive power flows, except where
specified otherwise, shall be used which have DC current outputs proportional to
the AC real and reactive inputs. The lineary shall be ± 0.25%.
The transducer output shall be 0 to 10 mA for single direction power flow, and 10 to 0 to + 10 mA for reversible flow, respectively~ representing 0 to 1.2 amps
input
current at
nominal rated input
voltage. The polarity of
transducers for
measurement of both forward and reverse power flow shall be such that power
flow into the busbar is positive.
The burden imposed on the primary circuit current
full rated input shall not exceed 2 VA and 12 VA respectively.

and

voltage

transformers

The additional burden imposed on the primary circuit current transformer at
rated input when the dc output is open circuited shall not exceed 2 VA, and
transducer's steady output voltage shall not exceed 25 volts.

at

full
the

Voltage transducers
Voltage transducers shall have a DC output current proportional to the AC input
voltage. The rated input voltage shall be 110 volts AC and the transducer output
shall be 0 to 10 mA representing 0% to 120% of rated input voltage.
The phase angle voltage transducer shall have an inverted
0 mA representing an input range of 0 to 240% of rated input voltage.
The burden imposed
shall not exceed 5 VA.

on

the

primary

circuit

voltage

linear

transformer

output

at

of

nominal

10

to

input

Current transducers
Current transducers shall have a DC output
current. The transducer output shall be 0 to
input current.

current proportional to the AC input
10 mA representing 0 to 1.2 amps

The nominal input current rating shall be 1 amp. The effective range of the

transducer shall be 0 to 120% of the rated input current and the accuracy shall
be ± 0.5% at full rated output.
The burden imposed on the primary circuit current transformer at nominal
maximum input shall not exceed 2 VA.

Frequency transducers
Frequency transducers shall have a dc output current proportional to system
frequency. The transducer shall record with an accuracy of ± 0.25% over the
range 45.00 to 55.00 Hz. The nominal input voltage shall be 110 V and the
output range of 10 mA.
Summators
Where specified or indicated on drawings, a summator shall be provided to
summate the outputs of several transducers. The summa tor output sball be 0 to
10 mA for single direction flow, and -10 to 0 to + 10 mA for reversible flow. The
error of the summator output shall be not more than ± 0.5% of full rated output
over as great a part of the output range as possible.
Transformer tap changer position indicators
Transformer tap changer position transducer shall have a DC output of current
proportional to the tap position.
The transducer shall have an output range of 0-10 mA representing tap position
1 to maximum tap position. Tap 1 should be at 1 mA and maximum tap at 9 mA.
Due account shall be taken of tap change transfer taps positions which do not
affect voltage output.
0.6.18.6.8 Position measurements
For the continuous remote position indication of valves, dampers etc. also
transmitters with impressed output signal of 4-20 mA shall be employed.
Therefore, electronic position transmitters shall be used.
Position transmitters of the potentiometer type will net be accepted.
Binary position switches shall be of the proximity type.
0.6.18.6.9 Contact devices
Where binary signals cannot be derived from an analog value. binary transmitters
e.g. temperature switches, pressure switches etc. may be used. Indicators with
integrated limit switches are allowed within package units. Preferably limit
switches shall be of the proximity type.
All switches shall be of robust design and reliable performance. The switches
shall have an adjustable switching hysteresis.

The set point and the dead band (reset point) of each switch shall be adjustablefrom
inside the case, over the full range specified. The set point and reset point
shall be indicated 011 the adjusting mechanism.
The switches shall be housed in robust, dust and moisture proof cases having
glanded cable entries and shall be suitable for the ambient conditions local to the
equipment, on which they are mounted.
Contacts of level switches, pressure switches, temperature switches, limit
switches, and of all other pilots shall be of the snap-action type. The creeping
action type will not be acceptable.
Contact devices for interlocking systems shall be separate, i.e. contact devices
serving commonly for interlocking and other purposes will not he 'accepted.
0.6.18.6.10 Vibration measurements
Vibration shall be measured at large rotating or reciprocating machinery for
protection and predictive maintenance. Suitable indications shall be provided in
the Central Control Room for each measurement point and the measurement
shall be suitably alarmed where high vibration levels may cause possible
damage or affect the safety of the power plant.
The vibration monitoring system shall be reliable, accurate, easy to maintain, and
suitable for use in such ambient conditions appertaining to the intended plant
installation.
Where feasible, standardization and interchangeability of components shall be
implemented.
The following criteria shall be used as a guideline for rotating machinery, in order
to ascertain the monitoring points, principles of what signal shall be measured,
what is displayed, and what mechanical conditions entail alarm and/or trip status:









Non-contacting proximity probes shall be provided unless otherwise specified
for measuring rotor shaft vibration and axial position,
Vibration measurements shall be in displacement microns peak to peak,
In cases which, because of process conditions, accessibility or noncritical
service, may entail the use of machine casing mounted vibration transmitters,
the transmitters shall be of the "acceleration" type incorporating a filter
network, if necessary along with integration in the monitor unit for vibration
read-out in velocity mm/sec RMS. For alarm only, one transducer may be
used. For alarm and trip conditions 3 transmitters shall be used with a voting
system (Le. one high reading out of three = alarm, two out of three = trip).
Contacting type of equipment shall meet the requirements of ISO 2954,
Velocity type transmitters shall be used as an alternative to accelerometers
when machine rotational speed and generated vibration frequency conditions
dictate,
Individual read-out of all channels shall be provided. Display shall be by
means of a multi-point indicator and digital selector,
Facilities for trend monitoring, using DCS integrated features, shall be
provided on the turbo-generator bearings as an aid for predictive maintenance purposes,
Buffered signals at the monitor shall be a requirement to enable external data
acquisition, if such is necessary,



Facilities shall be provided for the calibration of the instrumentation system.
0.6.18.6.11 Control valves
0.6.18.6.11.1 General
General requirements for control valves are contained in Clause B06 and further
details are given below.
0.6.18.6.11.2 Valve sizing
Control valves shall be standardized wherever possible and shall be sized for
optimum control. The sizing calculations shall include CV, noise and cavitation
calculations.
Valves bodies shall in all cases match the piping pressure and temperature
rating specifications as a minimum and the operating point on the valve
characteristic, i.e. lift/throughput curve should be within the 60-70% operating
range.
0.6.18.6.11.3 Valve bodies
For normal service duties valve bodies shall be of carbon steel with and
connections flanged raised face, unless process conditions dictate or otherwise
specified. Flange type connections shall in all cases match the piping
specifications as a minimum but never Iess than a pressure rating equivalent to
ANSI Class 300 specification. (See ANSI B36. 10 for full details rating
schedules.)
For liquid services with high pressure drop cage-guided control valves shall be
provided having the plug supported at the critical area.
For severely erosive service the fluid impact area inside the valve body shall be
covered by welded stellite.
For high pressure superheated steam service the complete valve body shall be
of Cr 13 Mo 44 or equivalent.
0.6.18.6.11.4 Plug characteristics
A linear characteristic shall be provided when the pressure drop across the
control valve under all operating conditions is more than 2/3 of the pressure drop
across the valve in the closed position. Unless otherwise approved an equal
percentage characteristic shall he provided for all other cases.
0.6.18.6.11.5 Trim material and stem packing
Control valve trims shall be of stainless steel ANSI 316 or equivalent ns n
minimum where appropriate according to the service, fluid and conditions.
Hardened and/or stellite plug and seal rings shall be used for the following
applications:


erosive service




wet steam service with pressure drop above 5 bar
general service with pressure drops greater than 5 bar.
For the above applications valves up to and including 38 mm shall have their
plug and scat rings made from solid stellite. For larger sizes, Ihc plug and scat
rings shall be made from stainless steel, ANSI 316 and be completely metal
coated wilh Stellite No.6
Valves shall be provided with teflon asbestos packing and a lubricator assembly.
For services with fluid temperatures above 200°C or below 10°C a normalizing
bonnet shall be provided to keep the packing box at ambient temperature
Bellow seals shall be used on valve stem packing for services with
dangerous/poisonous fluids: Suitable valve stem material shall be provided with
valves used on chlorine services or other services which become acidic when in
contact with a moist atmosphere.

0.6.18.6.11.6 Valve types
For normal duty services globe type valves shall be used.
Where very large sizes are involved (on high flows), butterfly type valves shall be
used and it will be "balanced torque" type disc usable to the fully open position.
The overall shaft rating shall be at least 25% above rated pressure as differential
across the closed valve.
Multi-stage valves shall be used on services, e.g. steam and gas, having
very high pressure drops which would result in supersonic velocity inside a
conventional body and shock waves in the piping creating unacceptable
noise levels.
For liquids the exit trim velocity shall not exceed 30m/sec.
For flashing service the exit trim velocity shall not exceed 22.5 m/sec.
For gas and steam the velocity head in line shall be less than 70 psia.
Supplier shall provide calculations demonstrating meeting the above
velocity requirements.
The maximum allowable noise level shall be 85 dB A or less.
Angle valves shall be provided:





for steam pressure reducing desuperheating stations of the
"combination" type
for erosive service, e.g. slurries
on applications where solid contaminants might settle in the valve body
on hydrocarbon services with tendency for choking.
Ball valves shall be used for on-off and throttling services under moderate
operating conditions.
Where alternative specifications are considered more appropriate then

details and justification shall be submitted to the Engineer for approval.

0.6.18.6.11.7 Installation
The installation shall include for upstream and downstream isolating valves and,
and for critical control valves, a bypass valve for each control valve on all
services. Unless otherwise agreed by the Engineer the bypass valve providing
tight shut-off shall have the same characteristics and construction as the control
main valve. Any exceptions or variations to this requirement shall be subject to
the approval of the Engineer. Where a service is subject to pressure above three
bar g a 25 mm vent valve shall be provided, between the upstream and
downstream isolating valves, in order to relieve the pressure to enable
maintenance to be carried out on the control valve. Control valves shall be
adequately supported in all cases and shall be accessible for maintenance. Local
pressure gauges shall be provided at the upstream and downstream of each
control valve.
0.6.18.6.12 Actuators
0.6.18.6.12.1 General
Unless otherwise specified actuators for modulating valves and dampers shall
either be pneumatic or electrically operated. Self contained scaled hydraulic units
may be considered where high thrusts or high speeds of operation are required
but each application shall be to the approval of the Engineer.
Actuators for ON/OFF duty or manually positioned units shall generally be
electrical motor driven, however the use of solenoid types on small valves shall
be allowed dependent on duty.
The various types and sizes of actuators shall be rationalized and as far as
possible each type shall be from a common manufacturer to facilitate
interchangeability and spares.
The operation of all actuators, control valves and driven units, shall be so
arranged as to ensure the safety of the "plant" under failure of control or
actuating supplies.
Unless specified otherwise, the failure of a control signal or actuator power
supply shall either:

a) cause the actuator to move to a safe position
b) freeze in its last operating position.
With either action the failure mode shall be suitably monitored and the plant
operator informed by some form of alarm.
Where pneumatic actuators arc used, an internal bias spring shall be used to
obtain motive power 10 reach the safe position in the event supply failure

Where the type of actuator offered does not have the appropriate fail-safe
facilities described above then the valve/damper shall have a second
valve/damper in series or parallel as appropriate, designed to provide the correctfailure
response.
When an actuator is locked or moves to a safe position on failure detection, it
shall not be allowed to return to automatic control without resetting action by the
operator after restoration of the supply/control signal.
The failure response of all actuators in .the event of the loss of the prime mover
(air pressure, oil pressure, electrical power) shall be indicated on the Piping and
Instrumentation (P&I) diagrams, valve Sc11cdules, etc.
All modulating and regulating actuators shall be filled with position measurement
for CCR indication of actuator position. This requirement applied irrespective of
the operating mechanism, whether electric, pneumatic or hydraulic.
All actuators which are controlled remotely from a panel or from the CCR shall
have independent control units and independent remote/local, auto/man
functions where specified or applicable. It is not permitted to gang several
actuators onto one signal output and independent positioning control shall be
provided for each actuator.
Where control requirements call for split range operation, the computing of the
split range shall be carried out externally from the actuator such that standard
signal inputs to the actuator are maintained.
All actuators shall include a mechanical device to show the true position of the
operating mechanism.
All actuators shall have a hand wheel for direct manual operation. The diameter
of the hand whelp and geared effort shall be such that they are reasonably
operable by one man. A lockable mechanical clutch mechanism shall be
provided to inhibit power control of the actuators when the hand wheel is
operated. The disengagement for hand control shall signal remotely to indicate
that the normal operation of the actuator is inhibited.
All actuators shall be provided with a local control facility. which in general will be
used for test purposes only. Such controls may take the following forms, as
appropriate or specified:

a) Control initiations (i.e. raise, lower, etc.) with lockable local/remote selection
when appropriate either on the actuator, in the direct vicinity of the actuator
or on its associated switchgear.

b) A portable test facility for injecting the appropriate position demand signal
either at the actuator or drive unit (switchgear or power amplifier).
0.6.18.6.12.2 Electrical actuation
Two classes of actuators are identified; firstly the motorized actuator which shall
cover the isolating actuator type and including actuator type required: for open
loop (binary) control; secondly the modulating actuator which shall cover the
switched types and continuous control type required for closed loop control.

(a) Electrical actuators for isolating and binary control
Isolating actuators shall have short time ratings appropriate to duty cycle type S2

10 min. to IEC
open/close cycles.

34-1,

and

n

maintenance

free

interval

better

than

10,000

Unless otherwise specified actuators with integral or separate switch units may
be offered. The contactors may be of the mechanical or static (thyristor) switch
type. If a static switch is offered then the switclll1 nit and actuator shall be
supplied by the same manufacturer as a complete system.
The following features shall be provided for each actuator:










DC open and close (raise and lower) command interposing relays
open and close travel limit switches (each with change over contacts)
torque switches in both directions (each with change over contacts)
open and close indicating lamps
open and close push buttons
instantaneous voltage phase sequence/failure monitoring relay
padlockable local/remote control selector switch
analogue actuator position signal shall only be supplied when specified
thermal overload protection.
The
DC
interposing
relays
(above)
shall
be
energized
by
the
control
instrumentation
system
power
supplies
and
shall
therefore
be
rated
to
compliant with the standard binary signal levels (48 V, ± 24 V or 24 V).

and
be

All
switch
units
and
actuators
shall
be
incorporated
in
enclosures
with
n
protection class of at least IP 54. Better type enclosures shall be provided
where
specified
for
special
applications.
Contractors
if
not
integral
with
the
actuator
shall
be
incorporated
in
the
actuator
boards,
in
in9ividual
compartments
logically
arranged
according
to
their
function.
These
cubicles
shall
be
accommodated in a switchgear room.
(b) Electrical actuators for modulating duties
Modulating
and
regulating
(inching)
actuators
to duty cycle type S4 20% 1200 cycles/h to
interval better than 50,000 hours in normal operation.
These
actuators
shall
be
principal types are recognized:


provided

for

shall
have
a
rating
appropriate
IEC 34-1 and a maintenance free

closed

loop

control

functions.

Two

Switched actuators
Each
actuator
shall
be
driven
by
a
duration
modulated
switched
power
signal
at
the
full AC
supply
voltage.
Each
shall
feature
either
electromagnetic or mechanical braking. However, the latter will only be accepted
on low power single phase actuators and a brake life in excess of 10 7
operations shall be guaranteed by the Contractor. They shall not be used
when full travel times of less than 20 seconds are required.



Continuous control actuators
For each actuator the drive voltage and current or frequency of
power
source
shall
be
continuously
varied
to
regulate
the
operation.
Each
shall
be
capable
of
slow
creep
operations
as
rapid stroke action and the operating torque shall be sensibly

the
rate
well

AC
of
as

independent of the speed of operation.
The continuous control actuator should be provided for all demanding
modulating control applications in which high torque, a wide range of
stroke rate and frequent correction is anticipated.
Unless otherwise specified actuators with integral or separate switch units
may be offered. Static power amplifier/switch units (thyristor units) shall be
provided for either type of modulating actuator.
If integrated within the actuator, the actuator and associated power amplifier
unit shall be manufactured as a composite system with a minimum of three
years of proven service reliability. In any case, the actuator and drive limit
shall be rated continuously for the stalled condition and three phase motors.
shall be provided for all actuators with ratings above 250 \watts.
The following features shall be provided for each actuator:
(i)

the drive unit shall accept an analogue (4 - 20 mA) actuator position demand
signal or pulsed raise and lower signals if an external position loop is provided

(ii) analogue actuator feedback position signal
(iii) a test facility
(iv) an override facility for
control interventions

stroking

the

actuator

in

either

direction

for

binary

(v) monitoring of common fault conditions such as thyristor drive fault, motor
temperature high, AC power supply failure, circuit continuity fault, high torque etc.
(vi) all necessary protection devices to protect the actuator and drive unit against
abnormal operating conditions.
Generally the actuator drive units shall either be integrated in the actuator or be
grouped and mounted within cubicles of appropriate enclosure standard. Unless
otherwise specified the later cubicles shall be located in an electrical switchgear
room to obtain protection from the normal plant environment.
The Engineer's approval shall be required where different types of actuators are
offered to those specified above or where the drive unit and actuator are
selected from different range of manufacture (preferably from two different
manufacturers). Additionally these shall he subject to a type test, approved by
the Engineer, to prove their satisfactory performance under equivalent operation
conditions.
0.6.18.6.12.3 Pneumatic actuators
All pneumatic actuators shall be provided with a positioner using a standard 0.2
to 1.0 bar signal.
Pneumatic actuators and drive units shall automatically return to the rest position
upon signal and/or air supply failure unless "process control" or the specification
requirements dictate for "stay put" response.

Where "lock up" devices are provided on those services requiring the actuator to
remain in the position prevailing immediately before an operating medium failure,
the following two methods of "freezing" are acceptable:
a)

The pneumatic system may be locked, but equipment used for this
purpose shall always be installed between a positioner output and an
actuator input.

b)

The final regulator may be locked by mechanical means upon receipt of a
falling supply prcsslI1"e signal.

All pneumatic control equipment, control drives rind control valves, shall be
capable of satisfactory operating on n main air supply pressure of approximately
7 bar g normal down to 5.5 bar g minimum.
On positioners where the output control air is of equal range to that of the input
signal air (e.g. 0.2 to 1.0 bar) they shall be furnished with integral pneumatic
"bypass switch" facilities for applying signal air direct to the actuator.
All positioners and electro pneumatic: converters shall be furnished with three
pressure gauges: air supply, signal input and control air output and an air filter
regulator set. All pneumatic tubing to drives and actuators shall, unless otherwise
agreed to by the Engineer, be in copper which shall be sheathed in PVC.
Where an electro pneumatic converter precedes or is integral with the positioner
then facilities are to be provided for the connections of portable test equipment
for the injection of electrical reference signals or pulses to allow the stroking of
the actuator for test purposes.
All on/off (open/close) actuation systems shall be provided with suitable tamper
proof adjustments for actuator stroking time, independent for the open and close
stroke.
All actuators which are in control loops shall be provided with robust precision
position measuring transmitters for CCR indication.
Solenoid valves for controlling the air to/from actuators shall be mounted on n
rigid mounting frame or plate independent from the actuator. It is not permitted to
mount the solenoid valve on' the actuator, unless agreed by the Engineer.
Solenoid valves shall not be merely supported from the air piping connections.
0.6.18.6.12.4 Solenoid valves
In lines with nominal diameters of up to DN 25, as well as for piloting pneumatic
actuators, suitable solenoid valves shall be used. Valves with power ratings up to
30 \V shall be controlled directly at 24 V DC from the I&C system. For powers
over 30 W, solenoid valves for a 120 or 230 V AC shall be employed. Solenoid
valves shall be fused individually. Electrical connections are made by means of
plug connectors with the mating connector forming part of the scope of supplies
0.6.18.6.12.5 Electro hydraulic actuators
Generally these actuators shall only be used where high thrusts are required
combined with fast operating times and the applications requirements cannot be
met by the standard range of actuators used on the remainder of the contract.

The units offered shall be or the self contained, fully sealed types which allow
removal of the complete unit to n clean room for any maintenance requirements.
Units accepting either 4 - 20 mA signals or pulsed input signals shall be
acceptable.
Failure of the internal hydraulic supply shall result in the actuator locking in its
last operating position or stroking to its fail safe position and a suitable alarm
being given to the operator.
0.6.18.6.13 Local instrumentation
All local instruments, necessary for local operation, maintenance and local
supervision have to be delivered.
The scope of supply shall comprise but shall not be limited to:










pressure indicator on the suction and discharge side of each pump and
compressor

pressure indicator at each heat exchanger inlet and outlet (except for sample
coolers)
temperature indicator at each heat exchanger inlet and outlet
pressure indicator upstream of each safety valve
temperature indicator at each bearing oil drain
pressure gauge at each tank or vessel if pressurized
differential pressure gauge at each important strainer or filler.
level indicator for each tank or basin
pressure gauge upstream and downstream of control valves .

pressure gauges at pneumatic actuators for air supply, signal input and control
air output.
All local instruments shall be as far as practicable be mounted free of vibration to
allow a good readability. Wherever required damping elements are to be used.
Local pressure and temperature gauge shall be installed on gauge boards either
grouped or individually depending upon site conditions.
All local indicating instruments and test connections shall be included in the
respective plant equipment as integrated parts. The scope of local indicating
instruments and best connections shall enable the local operator to properly
survey the equipment, and shall also allow to properly carry out all acceptance
and other tests. All Local instruments of main equipment (pumps, motors,
transformers) shall be readable from one side only, accessible for operation and
maintenance.

0.6.18.7 Racks, junction boxes
Instrument racks
Wherever possible, instruments and devices, e.g. transmitters, thermo element
cold junctions, terminal boxes, located in the field, shall be mounted on local
instrument racks. The instrument racks shall be installed with due regard to
control engineering needs, material-saving assembly and easy accessibility for
maintenance and checking work, and shall be constructed of standard angle
section steel.

Junction boxes
In order to simplify local collection of cables and distribution of signals and to
centralize connections in the plant the junction boxes shall be filled on nil the
necessary



cable crossover terminal points
electrical actuators

central collecting points for individual analog and binary signals and local
transmitters

central distribution points for local signals.
The necessary intermediate terminal boxes must at least have degree of
protection IP 55 in accordance with IEC-529 and must be equipped with the
necessary terminal strips and attachment components for the connection of the
cables. The necessary earthing terminals shall be provided for the earthing of the
boxes. In hazardous areas, terminal boxes shall be in accordance with EN 50019
or 50020, depending on zone classification.

0.6.18.8 Transmitter racks and piping
Wherever practicable, transmitter for flow, pressure etc., shall be installed
readily accessible in the vicinity of the measuring point, free from vibration
and protected against damage, moisture, fine dust, corrosive air, great
temperature changes, sun radiation and rainfalls.
The transmitters shall be grouped and assembled as far as practicable on
local transmitter racks or in cubicles (in open area).
The connecting lines between the primary elements and the transmitters shall
be installed with an inclination in such a way that no air pockets (e.g. in case
of liquid measurements) or no water locks can occur.
0.6.18.9 Programmable logic controller
Programmable logic controllers (PLC) shall be deployed in subsidiary
installations and systems of higher complexity and shall provide a more open
access for operation. Standard products of PLC manufacturers shall be used
for which software developed by the process suppliers and proven for the
specialized process is available.
The diversity of makes and types shall be kept to a minimum.
The Employer/Engineer reserves the right to stipulate make and type
following award of contract.
For signal exchange with the main DCS, PLCs shall be compatible with this
system. Depending on the amount of information to be exchanged, parallel or
serial interfacing shall be considered.
If only few signals are to be exchanged, parallel interfacing is preferred. Binary
signals shall be exchanged via volt free signals. Analogue signals (4 - 20 mA)
must be suitably decoupled.
If serial interfacing is used, the interface equipment between the PLC and the

DCS must be capable of communication using an industrial standard protocol. The
transmission baud rate shall be selected dependent on the application (e.g. 19200 baud
or higher). If commands are issued from the DCS to the PLC, the time between
command and PLC signal output shall not be more than 5 seconds. The same
requirement goes for answer back signals from the PLC and updating of displays of
analogue values coming from the PLC on the DCS monitor displays.
As a. minimum requirement, the offered serial link shall have a data integrity checking
and retransmission facility in case of error detection, independent of the DCS or external
system software. Hardware and software failures during data transmission shall be
monitored and alarmed.
The communication link shall be redundant (two cables) but only one traffic controller
shall be provided. In case of failure in the communication, quick manual switch-over to
the standby communication link shall be possible.
The functions realized in the PLC and the method by which they are invoked shall be
represented graphically similar to IEC-1131-3. Additionally, a description of the program
shall be supplied.
Programming devices with keyboard, VDU and printer for ease of programming, effective
on-line monitoring and diagnostic functions, together with the necessary equipment to
write in and to erase EPROMs shall be provided.
The PLCs should be selected from minimum no. manufacturers (preferably two).

0.6.18.10 Control cubicles
PLC hardware and other associated control equipment shall be installed in suitable
control cubicles. Where ambient conditions are suitable, these cubicles shall be set up in
a protected area, near to the secondary system to be controlled. Should this not be
possible, the cubicles shall be set up in local switchgear rooms or in local control rooms.
The protection class shall be IP 54 as stipulated in IEC-529.
The required control elements and displays (annunciation anti status lights, analogue
displays, switches etc.) shall be so configured that as far as possible they can be viewed
from the associated secondary system. Should it be necessary to place the control and
monitoring elements in the field, these shall be installed in separate, robust housings
(protection c1nss IP 65).
In preference LED displays shall be used. Ease of access and operation of the equipment
shall be ensured.
Where appropriate, visual display unit (VDUs) shall be employed for field operation and
monitoring.
All cubicles shall be adequately ventilated in order that the heat generated by the
equipment mounted there shall remain within the specified limits, even in the case of high
ambient temperatures that may occur in the event of failure of the air-conditioning
system.
Locally installed cubicles shall be suitable for the location in which they are situated and
shall provide adequate protection against dust, moisture or mechanical damage for the
equipment mounted therein. Sunshades shall be provided for all cubicle located
outdoors.

Table of Contents

Workshop
manufacturing and
pre-assembly
Works inspections
Testing during
manufacturing
Material tests
Tests at site
General remarks
Hydraulic tests
Test runs and functional
tests
0.7.2.2.4 Visual
inspectio
n,
checking
of
dimensio
ns, test
i
n
s
t
r
u
m
e
n
t
s

0
.
7
.
2
.
3
M
a
n
u
f
a
c
t
u
r
i
n
g
t
e
s
t
s
0
.
7
.
2
.
3
.
1
W
e
l
d
i
n

g
0
.
7
.
2
.
3
.
2
P
r
e
s
s
u
r
e
t
e
s
t
i
n
g
0.7.2.3.3
Testing of
corrosion protection
0.7.2.4
Mechanical equipment
0.7.2.5
Electrical
equipment
0.7.2.6
Control
and
monitoring
equipment
0.7.3
Testing at
site during installation
0.7.3.1
Erection
Tests
0.7.3.2
Pre-

commissioning tests
0.7.3.3
Tests
completion
0.7.4
0

on

xxx
0.0
xxx
0.1
xxx
0.2
xxx
0.3
xxx
0.4
xxx
0.5
xxx
0.6 xxx
0.7 Inspection and Testing
0.7.1
General
0.7.1.1
0.7.1.2
0.7.2
0.7.2.1
0.7.2.2
0.7.2.2.1
0.7.2.2.2
0.7.2.2.3

0.7.5

Reliabil
ity Test
run
Perfor
mance
tests

0.8 Abbreviations

0.7 Inspection and Testing
0.7.1 General
This section contains general requirements for inspection of material, parts,
equipment and workmanship of the Plant during manufacture, assembling and
erection and upon completion to demonstrate compliance with specification, codes
and standards and to ensure overall reliability of plant operation and performance.
Development
and
implementation
of
test
procedures for
the
construction
inspection, start-up and performance testing and capacity demonstration of the
Power Units and of the Plant shall be the responsibility of the Contractor. These
test
procedures
are
completely
subject
to
Owner/Owner's
Representative's
approval.
The Contractor shall be responsible for providing all supplies required for carrying
out such tests, except to the fuel used during Reliability Test Run and Performance
Tests.
The overall testing program for the Project shall consist of the following:







shop inspections and testing,
construction inspections, and testing,
mechanical completion, erection checks
pre-commissioning and commissioning tests
tests on completion
Reliability Test Run (6 weeks) and Performance Tests.
The
Owner/Owner's
Representative
shall
have
the
right
to
have
their
representatives present during inspections and tests of major Plant equipment and
systems in the workshops and during construction. The presence of the
Owner/Owner's Representative during any inspection or test shall in no way relieve
the Contractor of its responsibility for supplying the equipment or systems in
accordance with the milestone dates.
The Owner/Owner's Representative will be notified by the Contractor in writing at least
twenty (20) days prior to such testing and inspection:
Three (3) months after effective date of Contract, the Contractor shall submit to the
Owner/Owner's Representative all relevant test documents, which shall include:







test program
test standards
type of inspection and tests
tests which are to be witnessed by third parties
quality control procedure.
Six (6) months prior to the proposed start of commissioning the Contractor shall
submit to the Owner/Owner's Representative:





commissioning test program
commissioning procedures
tests on completion.
Six (6) months prior to commissioning the Contractor shall submit to the

Owner/Owner's Representative for the performance tests:







test program
test standards
manpower and deployment schedule of' the Contractor for performing the tests
forms of test records and report .
description of instrumentation to be used, including accuracy, and calibration
test results
method of data recording
method and equations/correction curves used for adjustment of recorded data to
the design conditions.
The results of all tests shall be
independent agency as appropriate.

certified

by

the

manufacturer, Contractor

or

Document files containing material certificates, welding procedures, test report etc.
shall be compiled for each item of plant and shall be suitably identified (including
equipment classification reference) and bound.

0.7.1.1 Workshop manufacturing and pre-assembly
All workshop fabricated components and parts of the plant shall, to the fullest
practical extent, be formed, machined, fitted, welded, stress-relieved. X-rayed,
adjusted, tested, cleaned and painted. The equipment shall be preassembled in
the workshop of the Contractor or his sub-contractors to the maximum possible
extent, then dismantled only as far as required for safe and proper shipment, in
order to keep erection work on site to a minimum. Equipment and parts shall be
marked, labeled or otherwise identified to facilitate assembly and erection on site.
Marks and labels shall be fixed in such a manner so that deformation or
obliteration shall not occur during shipment, storage and erection on site.
The equipment shall be designed and fabricated in accordance with the industrial
standards to reach the highest possible grade of reliability and a minimal and easy
maintenance.
Special attention shall be paid to standardisation and interchangeability of plant
components.

0.7.1.2 Works' inspections
The equipment to be supplied under this Contract shall be subject to works'
inspections and workshop tests.


The Contractor shall, after consulting the Owner/Owner's Representative, give
the Owner/Owner's Representative thirty (30) days notice in writing of the date
on and the place at which any plant will be ready for testing as provided in the
Contract and unless the Owner/Owner's Representative shall attend the place
so named on the date which the Contractor has stated in his notice, the
Contractor may proceed with the tests, which shall deemed to have been made
in the Owner/Owner's Representative's presence and shall forthwith forward to
the Owner/Owner's Representative duly certified copies of the test readings .



Where the Contractor provides for test in the factory of the Contractor except
where otherwise specified shall provide free of charge such assistance, labour,
materials, electricity, fuel, stores, apparatus, machines and instruments as may
be required and as may be reasonably demanded and approved by the

Owner/Owner's Representative to carry out such tests efficiently.
As stipulated in this section, the Contractor shall issue a quality assurance
programme, indicating the kind and extent of inspections and tests to be carried
out on plant components. These inspections and tests shalI
prove whether the
equipment fulfils the requirements of the Contract in view of





safety conditions
consideration of the applied standards and regulations
execution of workmanship
conformity with the present state of modern technology.
The following procedure has to be adhered to with respect to test certificates:
Whenever inspections or tests are carried out in the manufacturers' workshop, all
material certificates as well as all other intermediate test certificates, in accordance
with the agreed upon test schedule, shall be made available to the
Owner/Owner/Owner's Representative for inspection. Besides the latest issue of
the related drawings, indicating also the state of approval by the Owner/Owner's
Representative, shall be made available.
The same applies to the final works' inspections or workshop tests when all test
certificates have to be submitted to the Owner/Owner's Representative.
Further, for each kind of test, a "Test and Inspection Manual" has to be prepared
showing all steps of the test procedure as well as the relating standards and
codes.
All these test manuals have to be sent to the Owner/Owner's Representative.

0.7.2 Testing during manufacturing
0.7.2.1 Material tests
Test specimens shall be taken from all important forgings, castings, tubing, etc., in
accordance with the relevant standards and codes. Dimensions shall be adequate
for the purpose intended and the test specimen shall accompany the component
through all phases of the heat treatment. Before cutting or otherwise removing the
test specimens, these shall be permanently banded together with the forgings,
castings or components which they represent and, if requested, in the presence of
the
Owner/Owner's
Representative.
Except
where
expressively
otherwise
approved, all test specimens shall be machined to the dimensions specified in the
relevant standards find codes. Steel castings and forgings, in all cases, be
annealed before the test specimens are withdrawn.
Chemical analysis and mechanical properties of the material concerned shall also
be submitted.
All casting components shall be tested for compliance with the relevant standards
and codes and shall be suitable for the purpose for which the castings are to be
used. The chemical analysis and mechanical properties of the material tested shall
be provided by the Contractor. The results obtained from these material tests shall
be in compliance with the values contained in the relevant standards and codes
and with the figures quoted in the relevant sections of the Contract, if any X-ray
examination and ultrasonic examination of circumferential, longitudinal, nozzle

welded joints, stiffening rings, etc., shall be
compliance
with
the
standards
under
which
designed.

carried out by the Contractor
the
relevant
equipment
will

in
be

All castings and forging shall be subjected to X-ray and/or ultrasonic tests before
the start of machining procedures, in order to detect defects as early as possible
and
to
replace
in
time
defective
parts,
thus
avoiding
undue
delay
in
the
manufacture
and
delivery
of
plant
components.
After
partial
machining
in
the
Contractor's
workshop,
further
tests
may
be
performed.
No
repair
welding
machining of castings and forgings of major components shall be carried out
without prior inspection and confirmation by the Owner/Owner's Representative. In
case of a rejection, written and certified notice must be given to the Owner/Owner's
Representative, indicating also measures undertaken by the Contractor in order to
cope with the requirements 'of the Contract.
Major steel forgings
Purchase specifications shall clearly
and should include, but not be limited to:

a)
b)
c)
d)
e)
f)

state

the

quality

and

inspection

requirements

chemical composition range
heat treatment
mechanical test specimen locations
mechanical properties
magnetic properties (when applicable)
non-destructive testing
methods and procedures
stage and extent of application
recordable indication size
allowable indication size

g) thermal stability test (HP and reheat turbine shafts only)
Each forging shall be suitably marked with
transferred
throughout
all
machining
stages.
indicated on all documents relating to the forging.

an identification number which shall
The
identification
number
shall
be

Repair welding will not be permitted on rotating parts and on
proposal will be subject to approval by the Owner/Owner's Representative.

other

components

the

Rotor forgings
The profile of forgings at the stage of final ultrasonic
to minimize the regions where complete coverage is not possible.
Ultrasonic indications
AVG (DGS) method.

should

be

measured

by

the

Inspection

equivalent

flat

should be such

bottomed

hole

as

or

The toughness of rim and core (where applicable) material shall be evaluated by
testing charpy V impact
specimens over a
range of
temperatures and
thus
determining the 50% fibrosity fracture appearance temperature.

18
4

Allowable indication size and material toughness are interdependent design related
criteria and the Contractor must be prepared, if requested by the Owner/Owner's
Representative's Representative, to justify his proposals by reference to fracturemechanics calculations.
Bores,
when
provided,
shall
intrascope used for examination.

be

magnetic

particle

inspected

and

a

suitable

Major steel castings
Purchase specifications
and should include:

shall

clearly

state

the

quality

and

inspection

requirements

a)
b)
c)
d)
e)

chemical composition range
heat treatment
mechanical test specimen locations
mechanical properties
non-destructive testing
methods and procedures
stage and extent of application
recordable indication size
allowable indication size
f) other tests
g) standard weld repair procedure.
Each casting shall be identified by hand stamped
which shall be Indicated on all documents relating to the casting.

or

cast-on

reference

numbers

Non-destructive testing
Minimum requirements are as follows:

a) Crack detection of critical areas of castings which in the case of castings to
operate at high
accessible areas.
castings.

temperature or high pressure shall consist of 100% 'of all
Magnetic particle inspection shall be used for ferritic steel

b) Ultrasonic

inspection
of
temperature or high pressure.

all

surfaces

of

c) Ultrasonic thickness check of critical areas.
d) Radiographic examination adjacent

to
future
Standard Level of ASTM E446 or E186 as appropriate):

e) Radiographic

examination shall
indicated by ultrasonic inspection.

also

be

used

castings

to

operate

butt

weld

regions

to

assist

in

testing

all

surfaces

shall

be

satisfactorily

high

(Acceptance

defining

In addition to being applied as necessary quality control on as
inspections outlined in a) and b) above shall be applied to the finally
casting.
Prior to non-destructive
visually examined.

at

defects

cast items,
heat treated

prepared

Repair welding

18
5

and

Unacceptable
defects
observed
by
visual
examination
or
indicated
by
nondestructive testing shall be excavated by chipping or thermal gauging and grindingand their complete
removal proved by crack detection.
In the case of excavations which penetrate more than 25 mm or 50% of the wall
thickness
or
cover
more
than
10,000
mm 2
area
the
Owner/Owner's
Representative's Representative written approval of the proposed repair must be
obtained.
Only welders
used.

qualified

by

performance

tests

on

similar

cast

materials

shall

be

On completion of repair welded areas shall be ground smooth and carefully
blended into the surrounding material. The repaired areas shall be surface crack
detected, magnetic particle inspection being used for erratic steel castings and in
addition
ultrasonic
inspection
shall
be
used
on
castings
to
operate
at
high
temperature or high pressure.
Steel plates and sections
The
following
requirements,
which
may
be
supplementary
material standards, shall be considered when selecting material grades:





to

the

applicable

impact testing of plate or sections over 50 mm thick (impact requirements to be
dependent on application)
ultrasonic testing of plate where the presence of non-metallic may interfere with
the interpretation of ultrasonic testing of future welds
ultrasonic
testing
and
through
thickness
ductility
measurement,
where
the
application involves the risk of lamellar tearing in the material at regions of high
restraint (e. g. at set-on nozzle locations or cruciform joints)
ultrasonic testing clad materials to detect lack of bonding (proposed rectification
procedures
shall
be
submitted
for
the
approval
of
the
Owner/Owner's
Representative.

Reinforced thermosetting resin pipes (if in scope of supply)
Checks shall be made
relevant ASTM Standard.

on

all

raw

materials

to

ensure

that

they

All deliveries of resin shall be checked for consistency by viscosity
Any resins deviating from the manufacturer's published figures shall not be used.

comply

with

the

and

reactivity.

Testing of reinforced thermosetting resin pipes:


Long term hoop strength (type test for pressure pipes only)
In accordance with ASTM D2992 Procedure D with the exception that the test
results shall be extrapolated to determine the stress which the pipe can withstand
for a period of 60 years without failure. The lower 95% confidence limit at 60 years
shall also be calculated.



Hydraulic test

18
6

100% of the pipes shall be subjected to an internal hydraulic pressure test at the
manufacturer's works prior to delivery. The test shall be applied to a pressure
equal to 1.5 times the maximum working pressure stated for each classification
of pipe. The test pressure shall be applied for a minimum period of 5 minuteswithout signs of
leakage.
In addition to the above the first pipe and every thirtieth thereafter of each class
and diameter shall be maintained at test pressure for a minimum of 4 hours
without signs of leakage.
Each pipe and fitting shall be subjected to an internal low pressure air test at the
manufacturer's
works
prior
to
delivery.
The
test
pressure
shall
be
an
overpressure of 0.1 bar and this shall be applied for a minimum period of 5
minutes without signs of leakage or distress. Fittings which are of mitred
construction shall be manufactured from pipes which have successfully passed
the tests defined above.
• Dimensions
The dimensions and
with ASTM-D 2122


tolerances

of

all

pipes

shall

be

determined

in

accordance

Stiffness
A minimum of one pipe for every 30 pipes manufactured shall be tested for
stiffness in accordance with ASTM-D 2412 "Method of Test for External Loading
Properties of Plastic Pipe- by Parallel Plate Loading". A minimum of one pipe of
each class and diameter of pipe shall be tested.



Longitudinal and hoop tensile strength
The tensile strength properties of a minimum of one pipe for every 100 pipes
manufactured shall be measured in accordance with ASTM-D 638. A minimum
of one pipe of each class and diameter of pipe shall be tested



Cure
Curing, to be tested by the Barcol Hardness test determined in accordance with
ASTM-D 2583 standard: 100 % of the produced pieces. Minimum acceptable
hardness is 90% of the value recommended by the resin manufacturer of the
particular
resin
used,
when
non-reinforced.
The
sample
pipe
shall
also
withstand a commercial acetone test on the internal portion of the laminate.



Loss on ignition
A minimum of one pipe for every 30
accordance with ASTM-D 2584 "Standard
Cured Reinforced Resins".



pipes manufactured shall be tested
Method of Test for Ignition Loss

Joint tests
A minimum of two pipes in every] 00 pipes manufactured shall
tested in accordance with the requirements of section 7.2 of ASTM-D 3262.



in
of

be

jointed

and

Visual inspection
Each pipe and fitting shall be subjected
shipment in accordance with ASTM-D 2563.

to

a

complete

visual

inspection

18
7

before



Vacuum test
Vacuum test of pipe shall be carried out for each diameter once at beginning of
production. The vacuum to be applied shall be equivalent to the condition which
occurs during full vacuum. The corresponding derated vacuum for this test shall
be proved by the pipe manufacturer.



Failure of tests on completed pipes
In the event of a specimen not fulfilling the minimum requirements for strain
corrosion resistance, all pipes of that class and diameter which have been
manufactured shall be rejected and shall be rep]aced .entirely.
Any pipe or fitting which fails any of the quality control tests which are to be
carried out on each and every pipe or fitting shall be rejected. In the event of
any pipe failing any of the remaining tests outlined above that pipe shall be
rejected and the relevant test shall be carried out on a further ten pipes of that
class and diameter. If anyone of these ten pipes fails than the manufacture of
pipes of that class and diameter shall cease and the Owner/Owner's
Representative reserves the right to reject all the pipes of that class and
diameter
Thermal insulating materials
Materials shall be tested for bulk density, specific heat, compressive strength, fire
resistance under pressure, service temperature limit in accordance with VDI 2055
or equivalent standards.

0.7.2.2 Tests at site
0.7.2.2.1 General remarks.
The equipment to be supplied under the Contract shall be tested at Site during
erection and initial operation. These tests shall prove whether the equipment
meets the requirements of the Contract and the safety conditions, whether it has
been executed with satisfactory workmanship and whether the equipment is in
'conformity with the prevailing standards and regulations as well as with the
present state of modern technology.
Where manufacture or finishing is done at site, tests and inspections shall be
conducted as a replacement for an appropriate workshop test. The preliminary
check-out and test runs, the trial operation, the initial operation, the reliability test
run and the performance tests shall be carried out by the Contractor's personnel in
the presence of the Owner and the Owner/Owner's Representative.
Acceptance test readings shall be taken with calibrated instruments.
Waiving of any tests shall not release the Contractor of his responsibility to fully
meet the requirements of the Contract.
0.7.2.2.2 Hydraulic tests
Unless otherwise stated in the specifications or in the relevant standards and
codes, hydraulic tests at site shall generally be carried out on complete items of
plant, where applicable. This may, at the discretion of the Owner/Owner's

Representative and as far as applicable, include steam, water, air, gas and oil
carrying pipe work.
0.7.2.2.3 Test runs and functional tests
Test runs and functional tests shall be carried out on individ ual equipment where
practicable to prove the reliability and the correct functioning of the component and
its compliance with the stipulations of the Contract.
Rated operating conditions shall
conversion factors shall be applied.

be

simulated

if

possible

otherwise

appropriate

0.7.2.2.4 Visual inspection, checking of dimensions, test instruments
The Owner/Owner's Representative may from time to time make visual
examinations and may check the dimensions of plant equipment and the
conditions under which it is manufactured or erected at the Contractor's or SubContractor's premises to make sure that it complies with the relevant specifications
and drawings.;
Unless the calibration of test instruments and gauges is certified by recognized
statutory institutes, they shall be calibrated at the premises and in the presence~ of
the Owner/Owner's Representative or their authorized representatives. Test
calibration certificates shall be submitted for each test instrument.
0.7.2.3 Manufacturing tests
0.7.2.3.1 Welding
Welding procedures shall be qualified in accordance with the requirements of the
construction code/specification for the item of plant concerned and in the case of
critical plant items the tests shall be witnessed by an internationally recognized
inspection authority.
Welders shall be qualified in accordance with the requirements of the construction
code/specification for the item of plant concerned for all types/positions of welding
he may perform.
A system of positively identifying the work of each welder shall be maintained and
any welder whose work is the subject of multiple rejections shall be required to
undergo a requalification test. Any welder failing the retest may, at the discretion of
the Owner/Owner's Representative's Representative be disqualified from further
welding on items under this contract.
Welded fabrications shall be stress relieved when
standard or for dimensional stabilization prior to machining.

specified

by

the

applicable

Copies of temperature charts referenced with load items shall be included in the
test certification supplied for the relevant items.
All welds shall be visually examined and shall be of smooth contour, free from
cracks, undercut and other significant defects. Wherever possible the interior of
tubes etc. shall be examined using a suitable optical device where necessary.

Fillet welds shall be checked for size using suitable gauges
available
for
use
on
request
by
the
Owner/Owner's
Representative during an inspection visit.

which shall be
Representative's

Non-destructive examination of pressure and vacuum containment welds
Welds
shall
be
non-destructively
tested
in
accordance
with
the
construction
standard applicable to the item of plant. In addition the requirements of the
following Table shall be observed. This table shall also apply in cases where the
standards used for design and construction of an item of plant does not specify the
quality requirements for welds. Fault limitations to be subject of agreement with the
Owner/Owner's Representative's Representative prior to fabrication.

TABLE Non-Destructive Testing
T ype of Steel factor1
(shell)

C and C-Mn steels with C
content < 0.85
not exceeding 0.25%

> 0.85

C-Mn steels with C content
0.25 to 0.35% and C 1/2 Mo
steels
all
Low alloy steels except ll
CrMoV and 2 CrMo
CrMo V and 2CrMo steels
and 12% Cr all
ferritic/martensitic steels

Wall
thickness
(mm)

Inside
diam
(10m)

Remarks

Type and Extent of non destructive testing
Butt

nozzle

Fillet

<10

all

-

-

-

<

all

10%R

-

-

>40

all

10%M

10%M

<40

< 100

-

-

100% R
10%R

> 100

100% R

IO%M

10%M

>40

all

100% R

100% M

100%M

<30

all

10%M

10%M

10%R

Only applicable to:
Atmospheric systems
(excluded systems, which
handle chemicals, toxics or
flammable media).

Test after stress relief

Applicable below 50 bar

> 30

all

100%R

100%M

100%M

Test after stress relief

all

all

100% R

100%U

100%M

Test after stress relief

100% R

100% M

100% R-

100%M

100% U

100%U

all
<100
> 100

100%M
100% M

Test after stress relief
Test after stress relief

* Radiographic examination may be omitted if done on as-welded joint

19
1

T ype of Steel

Design factor
(shell)

Austentic Stainless Steels

< 0.85

>0.85

Wall
thickness
(mm)

Inside diam
(mm)

Type and Extent of non destructive testing
Butt

Nozzle

Remarks

Fillet

< 15

all

-

-

-

<30

all

10% R

-

-

> 30

all

10% R

10% D

10% D

< 100

10%R

-

-

> 100

100%R

10%D

10%D

all

100%R

100%D

100% D

Not applicable to: Butt
welds made from one
side only Operating
temperatures exceeding
200°C

<30

> 30
Legend:R = Radiographic examination
U= Ultrasonic examination
M=Magnetic particle examination
O= Dye penetrant examination
Note:
1.

Where 10% examinations are shown for pipe work under 100 mm diam bore this shall be the circumference of 10% of the welds by each welder selected at random

2.

Where 10% examinations arc shown for vessels or large diameter pipe work this shall be 10% of each weld length and must include all intersections of longitudinal

3.

Where partial exam' at ions reveal rejectable defects, adjacent welds or areas of weld shall be examined. In the event of rejectable defects being found welds shall be

4.

Welds in clad materials shall be tested in accordance with the requirements of the base material and the surface of the overlaid welds shall be dye penetrant

with a minimum of one per welder.
and circumferential welds.
subject to 100% examination.
tested throughout the length.

19
2

Non-destructive examination of structural welds
Welds shall be non-destructively tested in accordance with the construction
standard applicable to the item of plant. Where appropriate the following
requirements shall also be observed:



Magnetic particle testing of the tension side welds In major fabricated
girders and sections .
Ultrasonic examination of heavily restrained welds (e. g. cruciform joints)
where there is a risk of lamellar tearing in the parent material.

Weld repairs
Unacceptable defects observed by visual examination or indented by nondestructive testing shall be completely removed by chipping or thermal
gouging and grinding. The resulting excavation shall be crack detected prior
to rewelding.
Details of the original defects and repair shall be recorded.
Repaired welds shall be subjected as a minimum requirement to the same
inspection requirements as the original welds and test records should
indicate that a repaired weld is referred to.
0.7.2.3.2 Pressure testing
All items subjected in service to internal pressure or vacuum shall unless
otherwise agreed be pressure tested in the manufacturer's works and prior
to any internal or external coating.
Hydrostatic testing
All pressure vessels inserts or other parts of such vessels which are subject
to an internal pressure or vacuum during operation shall undergo a
hydraulic or other approved test. Unless otherwise stated in the
specification the test pressure shall be maintained for a sufficient period to
permit complete examination by the inspector.
Should it be necessary to carry out repair welding on stress-relieved equipment, it must undergo a stress-relieving process again. In all such cases the
hydraulic test must be repeated.
Particular attention must be paid to the temperature of water used for hydraulic
testing which shall not be less than 20°C. Prior to testing, metal temperatures
shall also not be less than 20°C. Where pressure parts 600 mm in diameter
and above are being tested the hydraulic pressure shall be raised to the test
pressure in stages during which the item shall be examined and all defects
rectified before the full test pressure is reached.
Suitable water shall be used as the test media unless otherwise agreed and
test pressures shall be in accordance with the applicable construction

178

19
3

standard but if none is specified then the test pressure shall be 1.5 times
the design pressure but not less than an overpressure of 3.5 bar. Test
pressure of vacuum containment items shall be agreed with the
Owner/Owner's Representative's Representative.
The test pressure shall be maintained for sufficient time to permit complete
visual examination of all surfaces and joints and in no cases less than
specified in the applicable construction standard.
The chloride content of water used for testing austenitic stainless steel
items shall not exceed 30 ppm unless immediate flushing with water of this
quality is done after the test.
Pneumatic testing
The Contractor shall apply pneumatic testing in cases where hydrostatic
testing is impractical or undesirable. Safety precautions, test pressures/
duration and degree of prior non-destructive examination of the subject
items shall be agreed with the Owner/Owner's Representative's Representative.
Pnelm1<\tic or gas leak testing supplementary to hydraulic testing shall be
applied in appropriate cases where specified by the applicable construction
standard.
0.7.2.3.3Testing of corrosion protection
Surface coatings






Following tests have to be performed before, during and after coaling:
• visual inspection of blasted surfaces according to DIN 55928 part 4,
annex 1
checking of coating material
• measurement of air humidity, air temperature and coating area
temperature (determination of dew point)
visual inspection of coating
checking of dry film thickness (DFT)
checking of adhesion.
Galvanized zinc coatings
Surfaces shall be visually inspected. Bare patches, lumps blisters or inclusions of foreign matter shall be cause for rejection.
Zinc coating thickness shall be determined non-destructively in accordance
with DIN 50981 or coulometrically in accordance with DIN 50932. For
coatings with a weight exceeding 900 g/m2 the coulometric test
method specified in DIN 50932 shall be used.
Hard rubber linings

Surfaces shall be visually inspected. Uneven surfaces, splits,
inclusion of foreign matter shall be cause for rejection.

blisters or

The thickness of linings shall be measured in accordance with VDl
Standard 2539 or equivalent. A tolerance of + 10% is permitted for rubber
coatings of 3 mm nominal thickness.
Hardness tests
standards.

shall

prove

compliance

with

the

rubber

manufacturers

The absence of pores shall be proved by the induction sparking test
method. The potential used shall be 5,000 Volts for each nun of thickness
plus an additional 5,000 Volts (i. e. potential of 20,000 Volts for 3 mm thick
lining).
0.7.2.4 Mechanical equipment
Rotating units
Balance testing of rotating units
Each rotating unit shall be first statically balanced and then dynamically
balanced (in the case of impellers this shall be done before and after
mounting of the service rotor shaft). A check balance of items that have
undergone over speed test shall also be made.
Vibration testing of rotating units
The vibration characteristics of rotating units shall be measured during
performance tests. Locations of measurement and standards to be
achieved shall, on request, be subject to agreement by the Owner/Owner's
Representative' s Representative.
Pumps
Running tests and performance tests shall be conducted on all pumps:
Performance tests shall be conducted through the full operation range of
the pump to closed valve conditions. Graphs indicating flow head,
flow/power absorbed, flow/efficiency, flow/NPSH and speed shall be
produced.
Results for feed pumps shall be assessed with reference to DIN 1944 class
1 (without construction tolerances), and results for other pumps to class II
or III as agreed.
The lubricating oil used in the test shall be of the same brand and grade as
that recommended by the manufacturer for service use.
Dismantling of the pump for visual examination of parts for damage
following test shall be done when required by the inspection standard, when
considered necessary by the manufacturer, or when requested by the
180

19
5

Owner/Owner's Representative's representative witnessing
performance tests. Replacement of parts following test
repeat testing.

the running or
shall necessitate

Steam turbines
The turbines shall be completely assembled with their control, stop and
governing valves on a suitable erection rig at the manufacturer's works and
shall be carefully inspected and measured for manufacture and assembly
tolerances. Functional tests shall be performed on the safety equipment
(running with steam is not requested).
Important items of turbine control equipment which cannot be adequately
tested during the main tests shall be separately bench tested.
Furthermore testing shall comprise:




balancing and over speed test of the assembled rotor
measurement of radial clearances
assembling inspection.
Air compressors
Air compressors shall be tested in accordance with the requirements of BS
1571, class C.1 part 1, ISO 1217, ASME PTC-9 or VDI 2045 - sheets 1,2
and 3 or similar standards. Any request for deviation from the test conditions shall be accompanied by the manufacturers' proposals for the adjustment of the correction factors contained in the standard.
Tolerances will be allowed according to ISO/R. 541.
Cranes and hoists
Where size permits cranes and hoists shall be completely assembled at the
manufacturers works and functional tests without load conducted.

0.7.2.5 Electrical equipment
Unless otherwise agreed, the electrical equipment shall be tested in accordance
with
the
following
recommendations.
Alternatively,
equivalent
standards approved by the Owner/Owner's Representative's representative
may be used, such as VDE. Type tests shall be made if type test
certificates certified by an independent test authority are not available.
AC Switcher for voltages above 1 kV
I EC 694 Specifications for AC switcher for voltages above 1 kV
IEC 56 High-voltage alternating-current circuit-breakers
IEC 267 Guide to the testing of circuit-breakers with respect to
out of-phase switching

IEC 298 High-voltage metal-enclosed switcher and control gear
IEC 420 High-voltage alternating current fuse-switch
combinations and fuse-circuit-breaker combinations
lEC 427 Report on synthetic testing of high-voltage alternating
current circuit-breakers
Metal clad switcher
Proof shall be provided of ability to withstand fault arcs in accordance with
amendment No.2 of IEC 298. Criteria no.1 to 6 shall be fulfilled. At least two
complete cubicles shall be tested (one cubicle being an end cubicle). If the
test has already been carried out on similar type switcher, type test
certificates may also be accepted:
Compliance with the IEC recommendation shall be fulfilled if
1. The plant is designed to be so resistant to pressure that no parts are
thrown out in the event of a short circuit.
2. The arc gases must be directed in such a way that they will not endanger
persons standing near the plant.

High voltage fuses
IEC 282-1, IEC 282-2 High voltage fuses
Power transformers
IEC 76 Power transformers
IEC 214 On-load tap-changers
IEC 404-2 Magnetic materials
Current transformers
IEC 185(1966) Current Transformers
Voltage transformers
IEC 186 Voltage Transformers
Generators
IEC 34, VDE 0530, IEEE 115, ISO R1680 and VDI 2056
• Generator test report
Comprehensive test reports for the generators are to be compiled and
submitted by the Contractor, which shall include:
• Description of the test method, equipment used and any limitations of
182

19
7

the test plant.


copies of the oscillographs recorded with appropriate calibration data




open circuit saturation, short circuit and loss curves for the generator
a performance chart of the generator (being a diagram of constant
stator and rotor current curves plotted on rectangular axis of MV Ar
and MW load) The recommended loading, stator core end heating
and stability limits shall be shown on the chart.
calculations of full load temperature rise for the stator, rotor and exciter. Any correction factors used to allow for different voltage current
and cooling conditions shall be justified by reference to published literature or to previous type tests.
calculations of the efficiency of the complete generator at 100%, 75%
find 50% load. Any correction factors for losses that could not be
measured at routine tests shall be justified by reference to published
literature or to previous type tests.
calculations of machine parameters such as transient reactance and
time constant, sub-transient reactance and time constant, short circuit
ratio,
synchronous
reactance,
negative
phase
sequence
reactance,
zero sequence reactance capacitance and also the harmonic analysis
of the neutral current.
circulation of full load excitation of the machine at rated power factor
lag1i.ing and at unity power factor, excitation V curves .









• Routine tests on generator





Generator rotor



ultrasonic examination



mechanical balance coupled with exciter rotor



over-speed test coupled with exciter

Measurement of 50 Hz rotor impedance
• Generator assembled:
• three phase short circuit characteristic test and current balance
check
• dielectric test
• measurement of insulation resistance
• measurement of winding resistance and resistance check of temperature detectors
• open circuit characteristic test and voltage balance, phase
sequence
check


segregation of mechanical loss and core loss



segregation of stray load loss



efficiency calculation

19
8



unbalanced load test for negative-phase sequence and zero se-quence reactance



shaft voltage measurement


oscillographing of verified voltage wave form and harmonic (,lIlalySIS



measurement of vibration



polarization index



tan delta measurement of complete winding

• bearing insulation resistance .
• Type tests on generator as far as type test certificates are not available
• sudden short circuit test at reduced voltage (30%, 50% and 70% of
rated voltage), extrapolated to 100% voltage
• equivalent heat run test consisting of windage and friction heat run,
open circuit heat run at 105% rated voltage, short-circuit beat run at
rated line current, open-circuit heat run at rated line voltage


measurement of open-circuit direct-axis transient time constant



noise measurement



moment of inertia




measurement of excitation response timeoverall characteristic coupled with generator
load
applicable
to
assembled
unit
consisting
voltage regulator, may be carried out on site






and
of

A

VR

generator,

cubicle
exciter

Routine tests on generator exciter (as far as applicable)


resistance of windings



insulation resistance



high voltage tests



short-circuit characteristic

no-load characteristic
MV Motors
IEC 34, ISO R 1680, VDl 2056
• Type tests (each motor type) as far as type test certificates are not
available





measurement of starting current and torque



efficiency measurement



heat run test



noise measurement

Routine tests (each motor)


measurement of winding resistances

19
9

at

no
and



no-load short circuit measurement



dielectric test



measurement of insulation resistance



over speed tests



check of motor vibrations

Low voltage switchgear
IEC 158
IEC 947

Low voltage control gear
Low voltage switchgear and control gear

IEC 439

Low voltage switchgear and control gear assemblies

IEC 529

Degree of protection provided by enclosures

IEC 337

Control switches (low-voltage switching devices for
control and auxiliary circuits, including contactor relays)
Specifications for circuit-breakers

VDE 0641
VDE 0170/0171
VDE 0660 Part 1
VDE 0670 Part 2

Electrical apparatus for potentially explosive atmospheres
Regulations for low voltage switchgear
Specifications for AC switchgear for voltages above
1 kV

Capacitors
IEC 70

Power capacitors

lEC 80

fixed capacitors for direct current, using impregnated
paper or paper/plastic film dielectric

IEC 103

Aluminum electrolytic capacitors for long life (Type I) and

IEC 143
lEC 358
lEC 384

Series capacitors for power systems
Coupling capacitors and capacitor dividers
Fixed capacitors for use in electronic equipment

Batteries, charging equipment and inverters
lEC 86
Primary batteries
IEC 119
Recommendations for polycrystalline semiconductor rectifier
stacks and equipment
lEC 146
Semiconductor converters

Lamps and accessories
lEC 81
lEC 82
IEC 155
IEC 598-1
IEC 188

T ubular fluorescent lamps for general lighting service
Ballasts for tubular fluorescent lamps
Starters for fluorescent lamps
Luminaries for tubular fluorescent lamps
High-pressure mercury-vapor lamps

IEC 262
lEC 400

Ballasts for high pressure mercury-vapor lamps
Lamp holders and starter holders for tubular
lamps

fluorescent

Telecommunication installations
IEC 215 Safety requirements for radio transmitting equipment
Aerials
IEC 597-2

IEC 169
IEC 492

Methods of measurement of essential electrical properties
of receiving aerials in the frequency range from 30 MHz to
100 MHz
Radio-frequency connectors
Measuring methods for aerial rods

VDE 0855 Part 1

Regulations for aerial installations

Power installations up to 1000 V
IEC 64
VDE 0100
VDE 0107
VDE 612

Regulations for the construction of power installations with
rated voltages below 1000 V
Regulations for setting up electrical installations in ,rooms
for medical purposes .
VDE Specifications for electricity distribution units for use
on construction an building sites at rated voltages up to 380
V AC and rated currents up to 630 A

Power installation above 1000 V
IEC 60
VDE 101
IEC 298

high-voltage test techniques
Regulations for the construction of power installations
with rated voltages above1 k V
BV metal-enclosed switchgear and control gear (incl.
amendment no. 2 "Internal Arc Test")

Protection equipment
Equipment for modular numeric protection systems (e.g. generator, distance, bus

bar, protection, etc.) pre-assembled in the relevant standardized boards I cubicles
etc. shall be tested in the manufacturers workshops as far as wiring and proper
function is concerned. Simulated inputs (binary signals, current and voltage inputs
from test power supplies) shall be used.
0.7.2.6 Control and monitoring equipment
All control and monitoring equipment shall be tested at the manufacturers'
works before dispatch to site. Certificates shall be issued for



synchronizing units
flow evaluators
On request the correct operation of equipment with specified temperature
and humidity limits shall be demonstrated .by tests conducted within the
limits.
Unless the calibration of test instruments and gauges is certified by
recognized statutory institutes, they shall be calibrated at the premises and in
the presence of the Owner/Owner's Representative or their authorized
representatives. Test calibration certificates shall be submitted for each test
instrument.
Electrical measuring instruments
All electrical measuring instruments shall be tested in accordance with the
following rules and regulations. Alternatively, equivalent standards approved
by the Owner/Owner's Representative's Representative may be used.
VDI 0410

Specifications for electrical measuring instruments

IEC 51

Recommendations for direct-acting indicating electrical
measuring instruments an their accessories
Direct-recording electrical measuring instruments and their
accessories
Safety requirements for indication and recording electrical
measuring instruments and their accessories

IEC 258
IEC 414

Electrical remote indication
Meters for active power,
equipment:

reactive

power

and

VDE 0418

Regulations for electric integrating meters

IEC 338

Telemetering for consumption an demand

similar

Calibration tests
The Contractor shall conduct calibration tests of the following
instruments and equipment:

remote

indication



all local indicators over the full range of the indicator



all recorders over the full range of the recorder



all binary transmitters over the full range including initial setting



all remote indicators over the full range of the indicator



all transmitters over the full range of the transmitter
• one of each type of indication loop with circuit resistance of the loop
increased to a value which is equal to the highest value expected, and
under worst case operating conditions



all superheated steam thermocouples



one of each type of thermocouple or resistance element



all kinds of analogue transmitters over the full measuring range
• all
modules
and
subassemblies
for
measuring
analogue limit monitors, flow evaluators, function generators




all quantity meters
all synchronizing units according to IEC standards
• the actual dimensions of all orifices, nozzles, venturi
be measured and certified by an independent authorized specialist.

and

control

nozzles

e.g.

have

to

Closed-loop control systems
All main closed-loop control systems shall be tested for polarity and function in accordance with the applicable standards. Control valves shall be
tested in accordance with mechanical functional tests on control valves
and
shall
be
performed
with
the
actuator
mounted
(open
to
closed
position and vice- versa). Actuators shall be subject to mechanical and
electrical function tests.
Sequence logic equipment
All sequence logic equipment shall be tested using simulated inputs.
Alarm annunciator and fault printing s)'stem
The alarm annunciator and fault
simulated inputs.

printing

system

shall

be

tested

using

DCS system
The system shall be thoroughly tested at the manufacturers' workshops
before dispatch to site. Test programs shall be devised and these shall
subsequently
be
made
available
to
the
Owner/Owner's
Representative's
Representative. Tests shall be made to ensure that the system operates
correctly within the ambient conditions as specified by the manufacturer
and that if these conditions are exceeded, Le. in the case of failure of the
airconditioning system, that the system will automatically fail safe and that

neither hardware nor software will be damaged.
0.7.3 Testing at site during installation
0.7.3.1 Erection tests
General
During erection all required erection tests as well as final erection checks
of the mechanical completion of the systems and part there of have to be
performed.
After successful mechanical
cates will be issued.

completion

Mechanical

Completion

Certifi-

The activities necessary for mechanical completion shall included but not
be limited to following testing:


visual inspection after unloading at site



checking of completion of relevant systems



completion of buildings and civil works



test of ventilating and air-conditioning units



alignment of rotating equipment coupled on site



safety audit



testing of site welds (non-destructive examinations)



pressure testing, leak tests, tightness tests



checking of pipe hangers, supports, guides, etc.



pipe line and equipment flushing and cleaning



chemical protection of piping systems



checking of coating



testing of cranes and hoists
Electrical equipment tests
The following checks and tests measurements shall be made:



screwed connections for correct assembly



terminals and terminal connections for correct assembly



checking of earthing connections and testing of earthing resistances



measurement of insulation values



verification of neutralization conditions



fire-proof partitioning



marking, inscription, provision of designation plates



rotating-field measurement



phase coincidence with 2 half-bus bars



voltage checks'



polarity checks in the case of DC voltages



fuses, over current trips, short-circuit trips, time settings, relay settings



switchgear and transformer oil levels



safety signs and warning signs
setting indicators, revertive (check-back) signals to the central control
room etc.
• checks on wiring and cabling for conformity with the constructional
circuit-drawings and plans
• checking and functionality testing of electrical systems according to IEC
standards




tests on the generator main bus bar



checking for the gas-tightness of individual main connections system




tests on the earthing and lightning protection system
acceptance tests and measurements of the earthing installations in
accordance with DIN 57 141 and of the lightning protection systems in
accordance with DIN 57 185
•tests on the lighting system
• proof of the minimum new value of lighting densities, checking of
correct operation both electrically and mechanically.

0.7.3.2 Pre-commissioning tests
Preconditions for the commissioning are the issue of the Mechanical
Completion Certificate and the availability of the accepted commissioning
test program and the Contractor's commissioning procedures; The Precommissioning Checks cover the functional tests of the individual items
and their alarm and tripping systems. Following tests shall be included:
Mechanical equipment




individual pre-commissioning runs of all rotating equipment such as
pumps, compressors, dosing equipment etc .
functional tests of the mechanical equipment
testing and adjustment of safety devices.

Electrical equipment
As far as not already covered by the erection tests the pre-commissioning
tests shall cover:



voltage tests
trip tests
•functional tests of the equipment
Control equipment

• Calibration tests of instrumentation, loop checking, functional
testing of control equipment, interlocks, protection inputs, etc.
0.7.3.3 Tests on completion
Preconditions of the Tests on Completion are the successful completion of
the pre-commissioning checks of all items of the whole system and the
satisfactory completion of the commissioning activities. On completion of
each commissioning activity to the satisfaction of the Owner/Owner's
Representative/Owner/Owner's
Representative,
the
commissioning
schedule shall be signed and dated by the Contractor and countersigned
by the Owner/Owner's Representative.
The Tests on Completion shall prove that the plant is prepared and
adjusted to ensure the correct functioning of the individual components
and of tile complete plant.
After successful completion of the Tests on Completion the "Authorization
to Start Reliability Test Run" shall be signed.


The Tests on Completion shall cover at least following tests:
protection tests
• operation of selected turbine train protection devices including
the following as a minimum


fire protection



boiler protection



steam turbine protection



generator

protection

•transformer

protection

•auxiliaries


method of alarm/trip condition reset for subsequent starting



operation of auxiliary systems
• method of changeover of main equipment to standby equipment
prior to turbine starting (see start-up tests) and during normal
turbine generator operation for lubrication and control oil system
and cooling systems




operation of fire protection systems
isolation procedures
method of isolation of plant equipment for safe shut-down and
maintenance procedures including as a minimum


HV station and unit supplies



LV supplies



oil systems (lubrication and control)



fire protection systems




protection systems/settings, in accordance with agreed design and
the requirements of the transmission system

start-up tests
• normal automatic start to preset load
• staged automatic including start to synchronous speed, manual
synchronizing (including synchro-check), automatic synchronizing,
manual and automatic loading


starting with stand-by auxiliaries



operation of all auxiliaries



verification of start up times and loading rates of power units, steam
generators and multistage flash units at various downtime
conditions ~



power unit, to test partial and full load rejection to demonstrate
• full
load
rejection
tests
to
measure
transient
maximum
speed
and
steady
state
speed
at
normal governor droop setting


method of resynchronize to be demonstrated



turbine bypass operation capability



Power unit/Plant, to verify and check
• operating
stability
when
operated
nominal
load
conditions
with
load
decreasing the electric load



between
variations

30%
by

and
100%
increasing
or



demonstration of the capabilities of the Power Units to
at rated voltage and frequency, at power factors and
conditions between. 0.85 (lag) and 0.95 (lead)

operate
reactive



start-up
including
facilities-

systems
standby




verification of vibration and noise emission guarantees
environmental
monitoring
equipment,
water
equipment, functioning tests and verification of guarantees

tests
of
checking

the
of

Plant
equipment,
facilities
automatic
change-over

and
of

quality

monitoring

• demonstration of the teledispatching and telemetering systems.
verification of active power response and voltage control
response
according
to
the
requirements
specified
in
the
network connection conditions



demonstration of proper controlling, monitoring and
recording according to the requirements of the grid code




verification of completeness of scope of supply
verification
of
24
hours
uninterrupted
MCR
operation.
As
precondition to the start of the reliability test run no adjustments,
manual
operation
and
other
intervention
are
permitted
during
this
verification.

0.7.4

Reliability test run (Initial Commercial Operation)
After successful completion of Test on Completion and after relevant
test
protocols
have
been
accepted
by
the
Owner/Owner's
Representative, the Contractor shall be allowed to prepare the Plant
Unit for the reliability test run. Reliability test run is also named as Initial
Commercial Operation.

The reliability test run shall be carried out for the power unit including
related equipment and systems and shall last for a period of six (6)
weeks each.
During the specified period, plant unit and related equipment and systems
shall be operated continuously and in accordance with the prevailing
power requirements of the transmission system or as required by the
Owner/Owner's Representative. If possible with reference to the grid, Unit
shall run at MCR.

The reliability test run will not be deemed to be completed unless the
relevant performance tests have been made.
In the event of interruptions to the reliability test run, for which the
Contractor is responsible, the length of the reliability test run can be
extended by a period equal to the total duration of the interruptions. If
such an interruption lasts more than 48 hours, the reliability test run
shall be restarted, after repairing the defect. The reliability test run
may be interrupted on three occasions, provided that the total hours of
interruption do not exceed 48 hours and that the Owner/Owner's
Representative is notified of the interruption in good time. Minor
adjustments to the control system are permitted with previous
agreement of the Owner/Owner's Representative.
0.7.5

Performance tests
After positive conclusion of the reliability test run period the Contractor
shall demonstrate by means of performance tests that the plant units
and the Plant including related equipment and systems can be tested
to prove the guarantee parameters.
Lower output and heat rate
The overall outputs under differing operating conditions shall be
determined and achievement of the performance guarantees given in
the relevant schedules shall be evidenced.
Performance
standards:

tests

shall

be

conducted

in

accordance

with

following

• the boiler
• generator
• steam turbine
• transformer

DIN 1942 (or ASME)
ISO 2314
DIN 1943 (or equivalent
ISO or ASME)
IEC 76.

The
curves
required
for
the
correction
of
the
power
output
specific
heat
rate
to
the
site
specified
ambient
conditions
shall
listed
in
the
technical
schedules
of
the
Plant
performance
and
turbine performance.
All
margins
required
for
instrument
inaccuracies
reasons shall be deemed to be included in the guarantee figures.

and

for

all

and
be
gas
other

Derating curves for the Plant performance shall be submitted by the
Contractor
with
tender.
The
curves
shall
show
the
Plant's
degradation
in power output and heat rate versus equivalent operating hours. The
curves shall be applicable up to and including major overhaul.
All special instrumentation shall be
by the Contractor. Meter accuracy
the Owner/Owner's Representative.

calibrated
shall be

for
as

the test and supplied
determined mutually by

0.8 Abbreviations
In general when
with KKS numbers .

using

abbreviations

care

shall

be

taken

to

prevent

ASC
AC
AVR

average site conditions
alternating current
automatic voltage regulation

COD
DC
DCS
EHV
EMC
ESP
GRP
H.R.C
BV
I&C
IR
KKS

commercial operation date
direct current
distributed control system extra
high voltage (400 kV)
electro magnetic compatibility
electrostatic precipitator
glass fiber reinforced piping
high ruption capacity fuse
high voltage
instrumentation and control
infra red
Kraftwerks-Kennzeichnungs-System ( PPCS) (Power Plant Coding

LHV
MNCL
MCR
MCS
MHS

System)
lower heating value
minimum continuous load
maximum continuous rating
mean cold season (winter) site condition
mean hot season (summer) site condition

O&M
OHL

operation and maintenance
overhead line

PC
PPCS
SCAD
A
SWG
SWY

pulverized coal
Power Plant Coding System (~ KKS)

TOV

Technischer Oberwachungsverein
(Technical Surveillance Association)
Deutsche Industrie Norm

DIN
VDE

supervisory control and data acquisition
switchgear (LV and MV)
switchyard (HV)

(German Industrial Standards)
Verein Deutscher Elektroingenieure
(German Electrical Engineers Society)

confusion

Steam Generator Plant

Table of Contents
B1.

Steam Generator Plant

1.1 General
1.2 Scope of Supply and Services
1.2.1

Boiler pressure parts

1.2.2
1.2.3

Drain and blow-down system
Firing and grinding system
1.2.4
Start-up and back-up firing system operating on
diesel fuel oil

1.2.5

Heating surface cleaning system
1.2.6
I (one) boiler wall inspection lifting equipment
(for two steam generators)

1.2.7

Refractory setting, thermal and noise insulation
1.2.8
Steel structure for steam generator with auxiliary
plants

1.2.9

Boiler accessories

1.2.10

Auxiliary steam boiler

1.2.11

Boiler and steam/water system cleaning

1.3 Special Technical Requirements
1.3.1

General

1.3.1.1
1.3.1.2

Design
Steam generator plant modes of operation

1.3.1.3

Fuel

1.3.1.4

Feedwater

1.3.1.5

Steam purity

1.3.2

Design and construction requirements

1.3.2.1

General

1.3.2.2
1.3.2.2.1

Steam generator
Furnace and connection pass for dry slag/ash extraction

1.3.2.2.2

Pressure parts

1.3.2.2.3Superheater (SH) and reheater (RH)
1.3.2.2.4 Economizer

1.3.2.2.5 Evaporator with steam drum
1.3.2.2.6

Supporting tubes and supporting bars

1.3.2.2.7

Headers

1.3.2.2.8

Safety valves, fittings and mountings

1.3.2.2. 9 Miscellaneous mountings
1.3.2.2.l0 Water level indicators
1.3.2.2.11 Sampling system
1.3.2.2.12Integral pipework
1.3.2.2.13Heating surface cleaning system
1.3.3 Firing and grinding system
1.3.3.1

Coal bunker

1.3.3.2

Coal feeders

1.3.3.3

Coal mills/pulverizers

1.3.3.4

Pulverized coal burners (PC burners)

1.3.3.5

Distribution of pulverized coal

1.3.3.6

Primary air fan (PA fan)

1.3.3.7

Inerting system for pulverizers and coal pipes

1.3.3.8

Start~lIp and backup firing system operating on diesel fuel oil

1.3.3.9

Diesel oil tank

1.3.3.10

Slop oil tank

1.3.3.11

Filters

1.3.3.12

Pipelines, foam pourcr

1.3.3.13
1.3.4

Electrical, control and monitoring equipment
Auxiliary steam boiler

1.3.5

Inside cleaning of boiler pressure parts

B1. Steam Generator Plant
1.1 General
Steam generator to be installed shall be of the natural circulation reheat type. The unit
shall be designed for pulverized coal firing (PC firing), balanced operation and out door
arrangement.
The Bidder has to check and to verify all relevant information as the basis for his offer.
1.2 Scope of Supply and Services
The scope encompasses all supplies and services necessary for fulfilling the objective of
the contract for 1 (one) complete coal-fired steam generator plant and their complete
auxiliary equipment, even if individual items are not specifically mentioned below.
Steam generator and accessories consisting of:

1.2.1 Boiler pressure parts
Comprising essentially



economizer with inlet and outlet headers



evaporator system with steam drum, headers and down comers



super heater and reheater with inlet and outlet headers



100% attemporator for super heater and reheater



all internal water and steam pipes and headers
• all necessary drain-, purges-, vent- and blow-down pipes incl. valves concentrated at
valve groups (double block valve)




blow-off pipes for safety valves and start-up valve incl. silencer
boiler mountings, valves and accessories:



feed water shut-off valve and feed water control valve with electric drive, check valve
incl. manual. operated control valve as bypass



automatic condensate traps with bypass and stop valves



complete drum-blow down valve group



drum emergency drain valve with electric drive.



local and remote water level indicator



local instrumentation



safety valves (2 x drum, 2 x super heater outlet, 4 x reheater outlet)



start-up control and shut-off valves, each with electric drive




live steam stop valve with electric drive
sampling system for feed water, boiler water and live steam incl. coolers, piping and
valves



casing, frame and supports



1.2.2

buckstays, tie bars, stiffeners and pipe damps as required
one complete set of doors and peepholes necessary for access, inspection and
supervision including service air nozzles connecting piping.

Drain and blow-down system
Comprising essentially




1(one)
continuous
blow-down
flash
tank
blow-off pipe, control valve and necessary equipment

(atmospheric
tank) incl. Cooling system,

1 (one) boiler drain flash tank with flanges, vent drain and

1.2.3

Firing and grinding system

connecting pipes.




Coal bunkers as steel structures



coal mills with motor, with shock absorbers, classifiers and special tools; Coal mill
specification: Capacity= 70% through 200 mesh, Hardness Grinding index=75, raw
coal moisture= 15%





mill primary air fan(s) with silencers on inlet and delivery sides with electric motor





two PC sampling studs with air scaling connections for each PC pipe

1.2.4

coal handling plants, including bunker isolating arrangement, feed chutes, mill
downshafts and coal feeders with all electrical drives, fuel bed depth regulators, coal
sampling points, remote sensors for electronic fuel bed depth and rotary speed
checkback signals

seal-air fans with electric motor
PC firing systems including low-NOx burners, PC distribution and delivery lines,
combustion air register, regulating, adjustment and isolating dampers as well all
drives, two PC sampling equipment incl. sieving device for each burner
flame detectors for the PC firing system
Automatic Coal mill's hard coal/stone rejection system, via denseveyor/ positive
pressure conveyor with 16 hrs storage and related others auxiliary, if necessary

Start-up and back-up firing system operating on diesel fuel oil
Comprising essentially:



main isolation valves outside of the boiler area



diesel fuel oil low-NOx burners



electric ignition and flame detection installation



pipework and valve stations inside the boiler area



burner management system



ignition and cooling air fans with motors



analog and binary equipment



flow meters for oil supply and return line and each burner



local control station



oil trays



diesel oil tank including unloading station



oil piping and valves



oil pumps, fillers



slop oil tank



slop oil pumps



slop oil pipes.

1.2.5

Heating surface cleaning system




Comprising essentially:
furnace wall steam soot blowers
semi-stroke rotary steam soot
electrical drive

blowers

with

retractable

lance

and




long retractable steam soot blowers
main isolating valve with electrical actuators and steam pressure reducing station with pipe work, instrumentation and valves for steam supply
as well as temperature-controlled drain valves with electric actuators




2 (one as stand-by) cooling and sealing air fans
automatic soot blower control and cabling of soot blowers and limit
switches to the cubicles, cabling between electrical and control
cubicles, including cable installation material (conduits, cable clamps,
etc.)



electrical cubicles with incoming feeder circuit breakers, motor protection and indicators for power consumption, pressure, temperature, advance and retract operation




field switchboxes with interlocks for optional local operation
automatic switch-over in the event of mechanical blockage.

1.2.6
1 (one) boiler wall inspection lifting equipment (for steam
generator)
Comprising essentially:
• lifting capacity
• one lifting winch
• type

3,000 kg
external winch

From the lifting winch, which has to be designed as a double-driving drum
winch, two hoisting ropes are to be transported.



the system of sufficient guide pulleys.
one working platform in light-metal
should consist of several parts

construction

The

working

The whole working platform is fitted with a guard plate on top. In addition the working platform has to be fitted with:

platform





2 safety catches



2 drive limit stops

plastic rollers to keep off the working platform from the boiler walls
• plastic wheels for transporting the working platform outside the boner
plant


The parts of the working platform are to be assembled by plug-andsocket connections.




One electrical equipment mainly consisting of:
switch cupboard at the lifting winch
• trip line for the working platform included are 2 conductors for a telephone connection




control panel for the working platform with
2 connections for hand lamps 42 V
• connections for the proximity switches of the drive limit stop systems
and the safety catches .



mercury cut-out to limit the slanting of the working platform



all necessary key buttons, conduit boxes and cross-cables



2 hand lamps, 42 V, 60 W



transfer drum for the trip line



two cantilever arms in Iight-metal construction



two hoisting ropes and two safety ropes (steel ropes)



accessories



2 hooks to fetch the safety ropes



2 movable transfer drums for the safety catches
• 2 auxiliary ropes to let down the safety ropes from the cantilever
arms into the boiler


3 leading-strops to fasten the working platform at the boiler-walls in
the range of the entrance openings



special tools



lay down construction on the furnace bottom.

1.2.7 Refractory setting, thermal and noise insulation



Comprising essentially
• moulded refractory lining and shaped fire bricks in the area of the
burners, access doors and peepholes, etc.
furnace moulded refractory



insulation and sheet cladding for thermal and noise insulation.

1.2.8

Steel structure for steam generator with auxiliary plants

Comprising essentially:
complete steel structure for boiler. coal bunker, lift shaft, pipe and
conveyor bridges and for auxiliary equipment
• 1 (one) open stairway as connection between platforms (taking into
account permissible escape route lengths)
• all necessary access galleries, stairways, ladders and platforms
• protection sheds (or hoods) for all equipment located outside such as
fans, actuators, electric drives, etc.
• roof and dust proof cladding for tripper conveyor
• dust proof enclosure for all conveyor bridges.


1.2.9

Boiler accessories

Comprising essentially:
boiler inspection cradles for fast inspection and repair of combustion
chamber and stock
• utility station for air, steam and water from connection branch of main
distribution supply up to the consumer, including hoses, hose couplings
and stop valves
• fire fighting equipment for steam generator, complete with all integral
pipes, valves, nozzles, hoses
• equipment and provisions for stand-still conservation of the steam
generator.


1.2.10

Auxiliary steam boiler (if required)
Existing 2 x 125 MW units have 1 (one) 10 ton/ hr capacity auxiliary steam
boiler. If these capacity is not enough for the proposed 250 + 10% MW
unit, then 1 (one) auxiliary steam boiler shall have to be supplied by the
contractor.
Comprising essentially:











(one) auxiliary steam boiler fired with diesel fuel oil, complete as
package with all systems and accessories including at least (to allow
start-up and critical operation without any external supply of steam):
economizer furnace and super heater
one forced draft fan
complete duct work from FD fan to the oil burners
oil burners
complete
instrumentation,
control
and
monitoring
equipment
burner
management
associated piping
feed Water system including feed water pumps
flue gas ducts from boiler outlet to the stack
steel stack.

1.2.11 Boiler and steam/water system cleaning
Comprising essentially:
• inside cleaning of pressure parts (boiling out and blowing out of coal
fired boiler and auxiliary boiler).
1.3 Special Technical Requirements
1.3.1 General
The requirements specified under B0 "General Technical Specification
and
General
Technical
Requirements"
are
to
apply, and,
where
applicable, further regulations from other sections of this specification.
The Special Technical Requirements
simplifying to boiler and accessories.

under

the

Section

B

1

refer

to

1.3.1.1 Design
The steam generator shall be of the radiant, natural circulation (single
drum) water tube type with integrated reheater.
The unit shall be of the balanced draught design, i.e. with forced and
induced draught fans.
The prescribed design and performance data of the boiler plant are listed in
the Technical Data Sheets B1/FB.
It is to have provision for firing 100% of MCR pulverized coal and 35% of
MCR design capacity with fuel oil firing for boiler start-up and low load
backup firing.
The furnace enclosing walls and the enclosing walls of the heating surface
section are welded gas-tight. The gas-tightness has to be tested. The
furnace itself, the radiation pass and the enclosing walls of the convection
heating surface sections are comprised of vertical membrane walls.
In order to compensate for any non-uniformities of flue gas temperature
over the cross-section of the boiler, each of the superheater and reheater
stages are separated into at least two parallel streams. The streams of the
individual stages are diagonally connected to each other.
The temperature control for the superheater and reheater is achieved by
means of spray attemperators which are located in the connection lines
between the stages of the superheater and of the reheater.
In order to permit cleaning of heating surfaces during operation and which
have become fouled by slag or fly ash, soot blowers have to be provided,

Steam is used as the blowing medium for the furnace walls and
for the convection heating surfaces.
The boiler is suspended from the roof of the steel support structure and
thus allows for thermal expansion downwards during operation. The boiler
enclosure is to be arranged as an extension of the boiler steel structure
which shall be c1added with metal sheets.
Firing system
Coal is supplied to the boiler units via belt conveyors. The coal bunkers are
charged by means of belt conveyors. It is planned that the belt installation
be in one line .
Boiler unit has 4 coal bunkers each with a capacity suffices for 16 hours of
operation at MCR and with design coal. It is planned to construct the coal
bunkers of steel.
By means of the coal feeders, the coal is withdrawn at a controlled
from the coal bunkers and supplied by coal feeders to the inlet chutes of
four coal mills (one standby). In these, the coal is pulverized, dried
classified. The coal is supplied to the burners via pulverized coal (PC)
with distributors. The classifier temperature is regulated by mixing with
air.
The main design criteria of pulverizer design has to be:
• MCR has to be generated by 3 pulverizers
coal, without supporting oil


in

service,

burning

rate
the
and
lines
cold

design

MCR has to be generated by 4 pulverizers in service, burning worst coal,
without supporting oil. When one mill is not available for operation due to
maintenance reasons, its output can be substituted by diesel oil.
Further, the diesel oil is used for ignition, cold and hot start-up and for low
backup firing.
The installation of low NOx burners is to be provided. As key measures for
the abatement of NO x emissions by combustion modification, air and fuel
staging. Flue gas recirculation can be incorporated, if necessary.
Air and flue gas system
The air and flue gas system is designed in a double flow path, each for 60%
of MCR. Provision for later flue gas recirculation system for decreasing the
NOx emission has to be provided, if necessary.
Air system
Combustion air is supplied by means of the FD fans, following which the air
flow is separated into primary and secondary air. The primary air is further
compressed by means of the primary air fans, following which part of the
primary air is diverted to provide cold air for controlling the mill classifier

temperature. For both the primary and secondary air, steam air preheaters are
arranged upstream of the regenerative heater. With the steam air heater the
combustion air is preheated sufficiently for there to be no danger of corrosion at the
regenerative air preheaters in cold section. Following the regenerative air preheaters,
the primary and secondary air is routed to the, mills or to the burners. Sufficient
measurements for all air flows and all burners will be applied.

Flue gas system
Following their exit from the boiler, the flue gases flow to the regenerative air
preheater, where they are cooled further and at the same time the primary and
secondary air is heated up. Within the downstream EP, the flue gases are free
of most of their dust burden before being routed to the stack via the ID fans.

Ash removal system
Bottom ash
In order to remove slag/ash from the furnace, submerged ash/slag scraper
conveyors and crushers are provided. The ash/slag discharged via belt
conveyor into ash silos. In order to maintain a seal in the furnace, dipper
seal plates are attached at the slag discharge.
Economizer Hooper cleaning system with fluidizing air system in
running condition
Fly ash
The fly ash from the EP and other points of the boiler where it collects is
conveyed pneumatically to the loading storage silos outside the boiler
area.
Sewage sludge
The lime slurry which are used for the power plants water pretreatment
process and amounts as lime sludge can be delivered with the coal to
the coal bunkers for burning it in the combustion chamber. Predrying of
the lime sludge is recommended.
Slag type furnace
Slag type furnace for granulation of the ash can be offered, provided that the contractor
shows evidence that he has already built at least 3 of such furnace type.

1.3.1.2 Steam generator plant modes of operation
Refer to part B0.2.6 (Mode of operation).
The steam generator with its auxiliary equipment is one of the principal
components fixing the dynamic capacity limits of the Power Plant. In order to
be able to follow the planned operation regime and above all the high
requirements for frequency support, during the design phase all required

206

measures shall be taken to ensure rapid availability after start-up and optimum
load-following behavior.

The following start-up conditions shall be Possible:


• start-up of the cold steam generator and cold turbine
start-up of the cold steam generator with the turbine still warm following
outage of one or two days



Start-up at any time of the warm or hot steam generator with hot turbine.
• start-up of the warm steam generator with cold turbine, if after a short
steam generator operating time during which the turbine did not roll, the
unit has to be started up new




start-up with a feed water temperature of 50 - 70°C
part-load operation with just one mill and with backup firing.
Boiler operation without the HP feed water preheaters shall be possible.
The excess air at the outlet of the combustion chamber when burning coal
shall be approximately 20% within the load range from 40% to 100% of
MCR.

1.3.1.3



The superheater outlet temperature shall be kept constant within the
load range from 60% to 100% of MCR with feed water injection.



The reheater outlet temperature shall be kept constant within the load
range from 70% to 100% ofMCR with feedwater injection.



The exhaust gas temperature at MCR when burning coal with 20%
excess air shall be 150°C at air preheater outlet.

Fuel
The steam generator and its auxiliaries shall be designed for pulverized
coal firing. Diesel oil shall be used only for start-up and back low load up
firing. Typical analyses of coal is given in the Annex.

1.3.1.4

Feedwater
The steam generator of natural circulation water tube type shall be fed with
turbine condensate and a small percentage of make-up water. The
feedwater shall be thermally deaerated and treated with volatile chemicals.
Its chemical properties shall be within the limits of the "VGB Directives for
feed and boiler water of steam generators" (latest edition).
Thorough supervision of feed water entering the steam generator shall be
provided.

1.3.1.5 Steam purity
During continuous operation the properties of the steam leaving the super'
heater shall not exceed the limits of the "VGB Directives for feed and boiler
water of steam generators" (latest edition).

1.3.2 Design and construction requirements
1.3.2.1

General
The steam generator and its accessories shall be designed for outdoor
installation with a suitable weather protection, insulation to completely
protect the boiler and its accessories.
The design of the steam generator and of the auxiliary equipment shall
envisage the life time of the Power Plant under the prevailing climatic and
operating conditions to be 30 years.
All noise emitting equipment shall be duly protected by silencers, sound
absorbing jacketing, insulation, etc. in order to meet the requirements as
specified in Section B06 and B07.
The pattern of the normal load jumps as dictated by the interconnected grid
are sudden due to load shedding and line faults. The Bidder shall describe
measures he has taken in the designing of the steam generator to facilitate
and secure these operating conditions.
Sufficient space shall be provided in the convection pass of the steam
generator for possible correction of the heating surface in case practical
results suggest such corrections to be necessary. The amount of space
shall be consider possible future installation of approximately 10% of total
superheater, reheater, economizer and air preheater heating surfaces.
The design of the steam generator and its auxiliaries shall consider the
possibility of preservation prior to or after commissioning by providing all
necessary connections and provisions as for example




heating of pressure parts by auxiliary steam
introduction of suitable chemicals
electric heating of motors, cubicles.
The Contractor's method of preservation shall be subject to the Client's
approval.

1.3.2.2

Steam generator
The steam generator to be installed shall be of natural circulation water
tube type and designed for dual coal and diesel oil firing. The unit shall be

208

of balanced furnace design with two regenerative air heaters, two FD fans
and two ID fans.
1.3.2.2.1 Furnace and connection pass for dry slag/ash extraction
The furnace shall be of the fully water-cooled welded membrane wall type.
The volume and dimensions of the combustion chamber shall prevent flame
impingement or excessive heat transfer upon any portion of the watercooled walls or other parts of the furnace enclosure at all operating
conditions.
The furnace size shall provide sufficient space for flame development and
shall allow complete and efficient combustion of the fuels specified before
leaving the furnace. Central or division walls are not accepted.
The configuration of the furnace shall be so that the air/flue gas flow will
reach all its parts and there will be not dead zones in which the formation of
an explosive gas/air mixture can occur.
The furnace outlet temperature (at first bundle heating surface inlet) shall
be selected under consideration of the initial deformation temperature of the
fuel with the worst ash specified.
The design will consider that no fouling in space superheaters for these
coals which can affect the reliability of the unit will occur. The supplier
should present detailed design of furnace- and gas outlet temperature
profiles to the purchaser during the design stage of the project for the whole
band width of all fuels specified.
The furnace and burners shall be such that when burning the types of fuel
specified and under all conditions of load up to the maximum output, there
shall be no flame impingement on any surface of the furnace walls and no
accumulation of slag on the walls, tubes or hoppers or other part of the
boiler units that will interfere with the continuous operation of the units.
Furnace design shall be designed primarily taking into consideration the
operation of the boilers on Barapukuria coaL
No additives are to be used to improve combustion, fouling problems,
corrosion problems or other reasons.
The furnace and convection pass shall be equipped with all necessary
access and inspection doors, access doors being located at both side walls.
A sufficient number of observation windows shall be provided in the
appropriate positions to allow for visual observation of the flames, the
combustion process and the roots and the tip of the flame of each burner.
Numbers of TV cameras and suitable position of openings shall be so that it
will be possible to observe the root and the tip of each flame, as well as the
number of burners in operation.
The combustion chamber shall be welded flue gas tight whenever possible,

22
4

the wall panels shall be reinforced by buck stays so as to withstand a flue
gas pressure inside the combustion chamber and all flue gas pathes of at
least ±70 mbar:
Access doors, viewing ports and peepholes shall be completely leaktight
against flue gas and accessible from the flooring or platform specially
provided. Access doors shall open and close without difficulty. Grips of
round steel bar shall be provided over the access doors. It should be
possible to replace sight glasses during operation.
All openings in the
deterioration by heat.

wall

of

the

furnace

shall

be

duly

protected

against

All loads of the furnace with framing and insulation as well as burners and
ductwork shall be led by the evaporating tubes and anchors to the supporting steel structure at the boiler top casing without causing bending stress in
pressure parts.
Slag/ash removal from the boiler shall be by means of a submerged
slag/ash scraper extractor. Ash falling into the hopper of the flue gas blank
pass and regenerative air preheater shall be directed to the wet ash scraper
extractor. The water in the slag extractor shall flow in a circuit via a cooler,
and shall be cooled and conditioned so that continuous or discontinuous
blow down is not necessary.
Provision shall be made at the steam generator for the attachment of
furnace inspection equipment. Inspection and repairs from inside of all walls
above the furnace bottom shall be possible.
The following are required to ensure a good combustion at all loads:





stable ignition across the total load range
complete furnace burn-out rate
• furnace temperature below the ash melting temperature across the load
range without big slag pieces
high fly ash retention figure
low NOx emission.
Particular
furnace:





attention

is

to

be

paid

to

the

following

characteristics

in

the

even flue gas distribution for intense heating of the furnace area
• good reswirling of the flue gas to the burner section to stabilize the
ignition of the pulverized coal;
• special deflection and removal of the flue gas flows for optimal fly ash
retention;
no or low CO content in the flue gases.
An optimal solution for the furnace design and shape is to be found by
means of special flow tests-'1' model experiments), Further it is to be
ensured that the ash carried in with the coal extract heat from the flue gas
considering possible change of flue gas profile which can lead to a
decrease in the end temperature of the furnace.

22
5

1.3.2.2.2 Pressure parts
The furnace hopper, the furnace, the evaporator membrane walls and the
membrane walls enclosing the convection tube bank shall be executed in
vertical tubing, welded completely gastight and observing the limits of the
specified design parameters. Tube penetrations through the membrane
walls as well as through the furnace roof shall likewise be executed in a
completely gastight welded design (welding sleeves).
All pressure parts of the steam generating unit shall be designed, manufactured, constructed and tested in accordance with the applicable standards.
The boiler pressure parts shall be completely self-drainable.
The Bidder shall submit with his Bid a material diagram indicating for each
single pressure part whether it is heated by flue gas or not, the following
characteristics:








the highest flue gas temperature,
the highest permissible steam temperature
the design pressure,
the working pressure,
the highest permissible material temperature,
the design material and wall thickness of the part
code number of the material
• temperature margin between operation temperature and calculation
temperature.
All stress calculation of the pressure parts shall be allow for the lifetime of
the plant as stated elsewhere with at least 50 shut-down and start-up per
year.
All tubes material shall be fabricated from hot or cold finished seamless
material and shall be ultrasonic tested.
Headers shall be of forged or
with inspection stubs on the
always be located outside of
closure elements to permit
equipment.

seamless drawn steel. They shall be provided
ends. Headers and spray attemperators shall
the flue gas stream and shall be fitted with
their direct inspection without any auxiliary

In addition, the spray attemperators shall be installed outside of the sheet
metal casing and easily accessible.
Grey cast iron may not be used in any pressure part.
The steam drum, headers, pipes and tubes shall be of approved
construction and manufacture, the suspension system and seismic
precautions shall be particularly indicated.
Supporting tubes for heating surfaces exposed to flue gas temperatures of
more than 400°C shall be cooled by feedwater or steam.

To avoid high temperature corrosion the connecting piece between
supporting tubes and heating surface shall be kept short as possible so that
their metal temperature will not exceed 570°C.
The wall thickness of the tubes shall allow for the thinning of the tubes
bends. All tubes of the convection heating surfaces shall be arranged in
line. The transverse spacing of all tube banks shall not be smaller than
double the tube diameter.
Wherever practicable the boiler shall be of completely welded construction.
In designing the steam generator the contractor shall minimize the number
of necessary fields welds. All components shall be shop prefabricated to the
largest extent. Headers shall be provided with stubs which are of sufficient
length to ensure that the heat of the welding process will not ,affect the
material of headers. All abutting tube ends shall be suitably prepared for
welding. All work on site, in particular welding and heat treatment, will be
subject to the same regulations as for Contractor's workshops.
All parts carrying hot media which are designed to specific creep rupture
strength shall be designed to provide a service life time of200, 000 hours.
1.3.2.2.3 Superheater (SH) and reheater (RH)
Superheater (SH) and reheater (RH)
The flue gas temperature at the inlet of the supporting tubes upstream the
first platen SH stage shall not exceed 1200°C (average measured 'versus
boiler width) considering fouling during operation. The flue gas temperature
at the inlet of final SH stage with normal fouled heating surfaces shall be
less than 1050°C.
The high pressure SH shall be divided at least into two parallel flows and
each flow shall consist of at least three (3) subsequent stages with
intermediate spray attemperators.
The RH shall be divided into at least two parallel flows with spray attemperators between the RH stages. RH system isolating valves shall be
provided for leakage test of reheater.
SH and RH shall be of the self-draining type.
Parts of the first layer of the SH and RH with distance less than 1 m to
steam sootblowers have to be equipped with protective shells for avoiding
erosion caused by soot-blowing.
The SH and RH heating surface shall be divided into tube banks, the
heights of which shall be limited to as defined in the Data Sheets BI/FB. For
convenient access the clear height between subsequent tube banks shall
not be) less than 1.2 m with access doors on both sides.
All fittings, spacers and supporting lugs exposed to flue gases shall be
made of approved heat and corrosion resistant materials.

To ensure an effective SH control the final stage shall have a maximum rise
in steam temperature at MCR of not more than 75 K for final SH stage.
Each spray water control station for SH and RH shall be fitted with a least 1
control valve, 1non-return valve, 2 isolating valves and 1 hand-operated
bypass valve.
Besides all measures taken by the Contractor to avoid unbalanced
temperature distribution across the boiler width the Contractor shall provide
and install at least 300 thermocouples as temporary provision well
distributed on evaporator, SH and RH outlet tubes and assure himself by
measurements during commissioning of the plants that at all operating
conditions no unbalanced temperatures exceeding max. allowable wall
temperature of the single tubes will occur.
1.3.2.2.4

Economizer
The boiler shall be equipped with an economizer which shall be designed to
preclude evaporation at any operating condition. Otherwise it must be
ensured that the operation of the boiler shall be possible if the HP feed
water preheaters are out of operation for a lengthy period. Its arrangement
shall be designed to be completely drainable. The water flow shall
preferably be upwards.
The heating surface shall be formed by seamless plain tubes which shall be
fitted in line.
The economizer shall be divided into banks. The height of the tube banks
shall be limited as defined in the Data Sheets B I/FB.
Parts of the first and second layer of tubes with distance less than 1 m to
sootblower have to be equipped with protective shells for avoiding of
erosion caused by soot-blowing.
All fittings, spacers and supporting lugs of the economizer tubes exposed to
the flue gas shall be made of approved corrosion and heat resistant
materials.
The feed connections to the drum shall be fitted with thermal sleeves.

1.3.2.2.5

Evaporator with steam drum
The evaporator system shall be designed and arranged to ensure reliable
water circulation during all operating conditions.
The gas-tight welded tube walls shall be tied together and stiffened by
means of buck stays which shall enclose the furnace and radiant section as
well as the convection section.
Low pressure steam shall be introduced in the lower headers to keep the
boiler warm and for heating up.

The design of the buckstays shall consider the expansion
welded tube walls during start-up and shall not result in additional forces.

of

the

gas-tight

The downcomers shall not be heated.
The drum shall be of the welded type with a manhole at each end. The wall
thickness of the drum shell shall be uniform throughout. It shall be amply
sized to ensure adequate steam volume to provide a suitable level control
and to preclude the possibility of carrying over of water during any transient
mode of plant operation as well as to provide adequate space for maintenance work and manual cleaning operation without removing any internal
fittings.
The drum shall be fitted
bution of the feedwater,
water from saturated steam.

with the necessary internals
with sufficient devices for

for the
efficient

uniform distriseparation of

Access manholes of hinged type shall be provided at each end of the drum
heads.
The drum shall be provided with dished ends and with the required nozzles
for the water and steam connecting tubes, drains, vents, blowdown, installation of safety valves, controls of pressure, temperature, analyzers and water
level. All drum nozzles for valves, fittings and mountings shall be welded to
the drums. All internal and external attachments welded to the drum shall
be made before final treatment.
The connection between drum and downcomers shall be well distributed
over the length of the drum. Entry of downcomers into the drum at the
dished ends shall be avoided. The downcomers shall be designed with
ample in cross-section-and shall be arranged at an unheated position to
avoid any disturbance of the circulation.
The feed connections to the drum shall be fitted with thermal sleeves:
The drum shall be provided with all suitable internal fittings such as:
• removable baffle plates located close to drum internal face, in front of
riser pipes.
• centrifugal or cyclic type separators or similar distributed on both sides
of the drum and adequately supported .
• steam
scrubbers
made
of
perforated
plate
and
located
below
the
saturated steam exhaust pipes .
• feed piping, perforated on its whole length, with adequate supports,
extended inside the drum to both sides .
• in case of chemicals injection into the drum for uniform distribution of
injected
chemicals,
adequately
supported
and
securely
attached
to
structural member.
• continuous blow-down tube extended along the whole length of the
drum and perforated along its whole length.

The attachment of drum internals of deflectors to the dram shall be such as
to ensure against displacement while the unit is in service, but, except
where specifically approved otherwise, they shall not be welded to the
internal surfaces of the drums. Bolts and nuts inside to drum shall be fitted
with cap nut. The drum internals shall be removable through access
manholes.
The drum shall be arranged so that it will not be exposed to combustion
gases.
The drum and the appertaining feedwater connections shall be arrange din
such a way that during interruption of the feed water supply an emptying of
the drum under the lowest water level shall not occur.
13.2.2.6 Supporting tubes and supporting bars
All tube banks located in zones of the gas path in which the gas
temperature is higher than 400°C, shall be supported by vertical steam or
water cooled supporting tubes. The design of the supporting tubes shall
meet the following requirements:
The supporting tubes and the appertaining headers shall be arranged to
take over the resulting heat expansion. The temperature of the cooling
medium shall be selected in such a way that the temperature difference
between the supporting tubes and the temperature of the wall through
which the sustained tube bundles penetrate will be a minimum.
The pressure drop, the flow distribution and the materials shall be selected
so that a sufficient cooling of all supporting tubes can be assessed during
start-up and when the boiler operates at minimum load.
A sufficient number of supporting tubes shall be installed with displaced
axis, so that the compartments inside and outside of the supporting tubes
can be inspected from the same manhole at the relevant level.
For tube banks located at the direct combustion chamber exit (which is
applicable for 1 /2 or 1 pass type boilers), the supporting tubes shall form a
screen to protect the tube banks against radiation. Suspension of tube coils;
on evaporator tubes will not be permitted.
1

The supporting tubes shall be fully self-drainable.
When suspension bars are required, special care should be given to the
selection of materials so that the low temperature corrosion can be
minimized.
The individual coils shall be supported by separate support blocks each.
Bifurcation of supporting tubes shall be avoided and the number of bends
for the supporting tubes shall be reduced to a minimum.

13.2.2.7 Headers
The headers shall be of seamless forged manufacture or solid drawn construction. The method of connecting the tube elements to headers shall be
by means of welding.
All distribution headers shall be adequately sized. To enable visual inspection of the internal space during maintenance periods, conveniently caps
on header panel sections shall be provided at sufficient locations to
facilitate such internal inspection. The closure of these must be of a
permanent type, either strength welded or seal welded. For headers,
where this inspection can easily be done by cutting pipes (e.g. overflow
pipe header), the inspection caps may be omitted.
The drum on headers shall be provided with shop welded tubular stubs of
the set-on type and thicker than the minimum calculated tube thickness.
These shall project a sufficient length to ensure that the welding of the
tubes will not affect the material of the drum and headers.
1.3.2.2.8 Safety valves, fittings and mountings
All fittings and
regulations listed

mountings

shall

comply

with

applicable

standards

and

The boiler shall be valved so that start-up and shut-down can be done
remotely from the control room. Subsequently, all valves, except the
isolating ones which will be shut-off only in case of repair, shall be electro
actuated.
It must be possible to operate the motorized valves by hand also.
The valves and actuators installed in the steam generator's steam/water
system shall be of an identical pattern and manufacture with those applied
for similar piping systems of the power station, which are subject of this
Contract.
Double valves on vents and drains and on tapings for instruments and
sampling points shall be installed on high pressure and intermediate pressure (reheat) pipes.
For the steam generator, the drain configurations shall be as follows:




superheater and reheater drains shall consist of one shut-off valve and
one throttling valve
vents shall consist of two shut-off valves
evaporator and economizer drains shall consist of two shut-off valves.
These valves shall be arranged so that the upstream valve when closed,
has. a spindle and gland which is load-relived and the operation shall be
performed with the downstream valve.

Venting, draining and spray water valve systems shall be combined in
groups. Groups of relating drains shall be discharged into common collectors.
Pressure test locks, feedwater stop valve and live steam stop valve shall
close perfectly tight in both directions (so that it shall be possible to perform
the hydraulic test for the boiler and the feed water and steam pipes independently).
Stop valves or groups of series connected stop
between of which condensate may accumulate in
protected against pressure in excess of the allowable limit.
The steam generator shall be equipped with
complete drainage of the boiler water/steam
have non-dangerous dischargers.
In lines where self-closing
device shall also be installed.
Where maintenance
in
between
shall
operation.

blow-down

valves, in the bodies or
closed condition, shall be

devices for draining to assure
system. All drain lines shall

devices

are

installed,

at full pressure is required, double
be
provided
enabling
maintenance

shall
line.

be

fitted

to

number
the

boiler

of

safety

drums

and

valves

of

superheaters

The safety valves, installed on the boiler drum,
reheater shall be set to blow in a predetermined
necessary for gauging the safety valves and for
shall be supplied.

where

approved
and

shut-off

isolation with drain
or
repairsduring

The components shall be fixed in approved positions and
shall comply with the requirements of the piping and valve specifications.
The
corresponding
capacity-

another

on

applicable

design
the

hot

and
reheat

superheater outlet, and
sequence. All equipment
hydraulic test purposes

Indifferent of the dopted design code, the operation of the HP bypass
stations as safety device, shall be mandatory. Set points of HP bypass
stations and safety valves in the HP system shall be selected, so that the
HP bypass reducing stations will open first. During a trip of the turbine at full
load and availability of the HP bypass reducing station, no safety valves on
the HP side shall open. One pulse at least shall be transmitted to the
control system of the HP bypass station from the saturated steam portion of
the boiler.
The set pressure of the reheater safety valves and of the LP bypass
stations shall be chosen so that opening of the reheater safety valves will
be avoided to the largest possible extent. .

The safety valves at superheater outlet shall always lift before the safety
valve on the drum opens. The superheater safety valves shall have such
capacity that the superheater cannot be overheated when also the drum
safety valves are blowing. The safety valves shall be of the spring loaded
type.
One blow-off station consisting of one throttle and one shut-down valve
connected in series with the relating electric actuators shall be installed in
the hot reheat line. The capacity of this station shall be determined in
accordance with the following requirements:


operation of the station during start-up until achievement of pressure on
which the LP bypass reducing stations enter into operation (if required)
• in case of non-availability of LP bypass stations, a start-up until synchronization of the turbine shall be possible.
Silencers of the absorption type or of the combined multiOle expansion!
absorption type shall be provided for all safety and electrically operated
blow-off valves installed on the steam generator. Start-up valves, safety
valves on superheaters and reheaters should be connected to their own
silencers.
1.3.2.2.9 Miscellaneous mountings
For cold and hot reheat pips leading to the turbines, pressure test locks
shall be installed in the vicinity of the steam generator so that it will not
be required during a pressure test of the boiler, to block the supports of
the whole piping system.
If the pressure and temperature of the interconnecting steam line to be
provided is not sufficient for the sootblowers, fuel atomizing and other
necessary purposes, the boiler shall be provided with its own reducing
valves in adequate number and size.
An adequate number of thermocouples and fixings shall be
measure the superheater outlet header, inside and outside
as temperature difference for monitoring of thermal events
have an influence on headers life time. Drum metal
difference measurements shall be supplied.

provided to
temperature
which may
temperature

The corresponding number of blowdown and drain valves for the drum,
furnace wall bottom headers, for superheater and headers shall be
provided, each set including two valves of an approved bore and type
arranged in series.
The necessary vents
for venting
the economizer, drum
and
superheaters, reheaters shall be included. Nozzles and isolating valves
and test connections for all remote and local pressure indicators shall be
supplied.
1.3.2.2.10 Water level indicators
Two local drum level gauges, showing the full scale complete with

lighting fitting shall be included. The electrical energy for these fittings
will be taken from the DC supply of the power station.
One gauge shall be fixed so that the water level can be easily seen
direct at the boiler drum level. The second bicoloured gauge shall be
fitted to enable the water level to be seen from the location of the
feedwater control valve.
The gauges shall be fitted with drains, and valves for shutting off and
blowing through. Double isolating valves shall be provided.
Two sets of nozzles and isolating valves for water level transmitters
shall be provided under the Section B9 (Instrumentation and Control
Works). All water level devices shall be provided with independent drum
nozzles.
The gauge glass fittings shall be of forged steel and shall be designed
so that they can be removed as a complete assembly without shut-down
of the boiler.
The water level transmitters shall be connected to a separate pair of
branches on the drum for a water level indicator on the main control
panel and for the three-element feedwater closed loop control:






one high and one low level water drum alarm (each independently
connected to a pair of branches)
one independently working low water safety feature for boiler trip
the lower limit of indicating range of the water gauges shall be at least
30 mm above the uppermost pass and at least 30 mm below the
minimum water level
all level gauges shall be provided with a retaining device, so that at
bursting of glass the boiler does not need to be shut-down.

1.3.2.2.11 Sampling system
Sampling equipment shall be installed in all places where required for
local and remote supervision of operation, for early recognition of
disturbances and for the clarification of the causes of damages.
A complete
sampling
system,
including
sampling
coolers
with
connections, nozzles, valves, fittings and pipes shall be provided to
obtain representative separate samples of live steam condensate, boiler
water and feedwater.
The sampling coolers shall be fitted with stainless steel coils and
219

stainless steel piping connections up to the take off point.
The position of each sampling point shall ensure representative samples
and should be led to one common sampling station or shall be
combined in a minimum number of groups (if because of long sampling
pipe length the danger of falsification of analysis would exist).
All sample coolers shall be provided with stainless steel trays. The drain
of these trays shall be laid to the waste drain system.
The sample coolers shall be designed so that no
consequences will occur on interruption of cooling water supply.

detrimental

The throttle valves shall be located downstream of the sample coolers
in. order to avoid steaming of the sample.
Owing to the elevated temperature of the cooling water, all
measurements for which a temperature correction is not possible (e.g.
02 measurement) shall be cooled by a cooling aggregate or separate
electric sample coolers shall be provided for each measuring point.
On components where the steam or water flows in two parallel streams,
the tapping connections shall be provided in both streams.
Sample coolers of the continuous flow type shall be installed for all
points where remote quality recording is required, but at least for,the
following points:


feedwater inlet to economizer
• boiler water (tapped from the continuous blow-down line or from a
downcomer)




live steam (tapped from the main steam line)
reheat steam (tapped at reheater outlet).

1.3.2.2.12 Integral pipework
The pipes shall be routed in such a manner as to avoid destructive
expansion due to temperature changes. The routing of the piping shall
allow for complete drainability of the system.
Provision shall be routed in such a manner as to avoid destructive
expansion due to temperature changes. The routing of the piping shall
allow for complete drainability of the system.
Provision shall be made for heating-up purposes of safety valves and
main steam stop valve.
Safety valve escape pipes with all necessary expansion joints, anchors,
supports, weather cowls and roof collars shall be provided. Drain pipes
to remove condensed steam in the escape pipes shall be led to

.collector dishes located at a convenient level.
Exhaust lines of flash tanks and safety valves to be extended above the
boiler roof level.
In no phase of operation excessive quantities of vapour or water are
allowed to be discharged which may spill over equipment or be
aspirated by air fans.
Underground
minimum).

drain

lines

to

be

of

heat

resistant

material

(80°C

1.3.2.2.13 Heating surface cleaning system
A complete plant for on and off load cleaning of the boiler heating
surfaces shall be provided. The cleaning installation shall meet the
requirements for coal and diesel fuel oil operation of the steam
generator.
Soot blowers
The steam generator shall be equipped with a suitable
system in order to maintain a reliable and economic boiler operation.

sootblower

Sootblowers shall be located where fouling of heating surfaces may
occur and the heat transfer may be affected.
For cleaning the furnace sootblowers of wall cleaning type shall be
provided.
In the range of flue gas temperature above 600°C long retractable
sootblowers shall be provided on both sides of !he boiler. All tubes and
mountings exposed to flue gas shall be of an approved material with
efficient corrosion and scale resistance.
All sootblowers shall be located at sufficient distance from the nearest
tube row in order to prevent erosion. Additionally, parts of the first tube
row less than 1 m distance from sootblowers shall be fitted with
protective shells.
Steam for sootblowers shall be taken out of the superheated and
reheated steam system. The contractor shall provide a steam reducing
station. All steam piping and drains shall be provided according to the
specification for pipework.
For regenerative air preheater soot blowers shall be provided on the hot
end as well as on the cold end also.

Sootblowers
shall
be
operated
by
electrical
drives
with
local
pushbuttons
as
well
as
a
common
panel
for
the
whole
sootblower
system. The preheating of the piping system as well as its drainage and
the operation of all sootblowers in a suitable sequence shall be actuated
by a master pushbutton from this panel. Failure in the operation shall be
indicated by alarm lights of the panel and a common alarm signal will be
conducted to the unit control room.
Two cooling and sealing
for flue gas corrosion.

air

fans

(on

stand-by)

shall

avoid

the,

tendency

All
retractable
type
sootblowers
shall
be
adequately supported and
be
provided with lateral protection against accidentally knocking as well as
to
provide
correct
guidance
during
insertion
procedures.
All
sootblowers
shall be suitably guarded to prevent personnel coming into contact with
moving parts or hot surfaces.
Accommodation
for
test
pressure
gauges
shall
be
provided
in
the
medium supply pipes and/or at the blower lance to check the blowing
steam pressure. The pressure shall be adjusted as necessary to obtain
the optimum cleaning conditions.
The
numbers
of
sootblowing
cycles
shall
be
three
per
day
maximum.
Sootblowing
shall
be
possible
at
any
load
of
the
generator.

as
a
steam

Adequate lubrication of the sootblowers shall be provided.
The
arrangement
of
sootblowers
and
platforms
interference and shall allow a free walking height ofat least 2.1 m.

shall

give

no

Washing installations for heating surfaces
The
selection
and
supply
of
equipment
generator shall meet the following requirements:
Equipment
and
washing
minimum demand of water.

process

shall

be

for

washing

chosen

with

of

the

regard

steam
to

a

Washing of convective heating surfaces and furnace shall be made by
hand by using hoses. All relevant hoses, washing water utility stations
at various boiler platforms, connecting pipes and/or pumps (if required)
from the water supply source to the utility stations and drainage ducts
shall be provided under this Contract.
For
the
regenerative
air
preheaters
shall be provided which must be
preheaters when the unit is in operation.

a
fixed
suited to

installed
washing
system
wash one of the air

Regenerative air heaters shall be supplied and designed to permit off222

23
7

load washing with process water. The system shall include all supply
pipes, pumps dosing system, discharge pipes, dust separator complete
with internals, discharge ducts and pumps (if required) from the dust
separator.
Drainage pipes of air heaters washing system shall be provided with
double shut-off valves and drain valves in between, in order o exclude
the intrusion of water into the dry ash removal system. The same shall
apply also for other drainage points where dry ash and washing water
will be discharged into the same piping system.
1.3.3 Firing and grinding system
The steam generator shall be equipped with a complete coal grinding
and firing system and an ignition and back-up firing system based on
diesel fuel, comprising the following main items:


coal bunkers



coal feeders



coal mills



combined coal/oil low-NOx-burners



primary air fans (P A fans)



diesel fuel oil systems



PC burner pipes
The PC firing as the principal firing for the boiler shall be designed for
direct firing. It shall be capable to cover the specified boiler turn-down
range. The MCR load point and partial loads of 30% MCR and greater
shall be achievable without the aid of the ignition and backup firing, but
taking into account the specified fuel range. Depending on the coal
quality, in the minimum load range it shall be permissible to operate the
ignition, back-up and support firing system.
The number, type and arrangement of the PC burners shall be decided
by the Contractor. It shall be guaranteed that the prescribed design data
and operational requirements are met completely.
Of particular importance is that the statutory emission standards for
nitrogen oxides will be met.
Also the isolation arrangements shall be of low wear design and require
versionly no maintenance.
The burners shall be so assigned to the mills that if one or more of the
mills is switched off or fails, asymmetric fireside temperatures wiIl be
avoided.
Shut-down of one or more complete burner levels shall also serve the
purpose of achieving the required minimum load. Cooling measures for
the burners which are not in operation have to be foreseen for avoiding

damages caused by furnace heat.
It is essential that the Plant shall be dust tight in every respect and all
bearings and working parts shall have dust proof housings.
For monitoring the flames of the PC firing system, flame detectors shall
be provided. Which in the event of the failure of its associated burner
group will not be effected in its action by extraneous light or spurious
radiation from the furnace. The offer shall be accompanied by a detailed
description and drawing of the combined burners and a reference list.
The ignition and backup firing system shall be designed for the fuels and
load range as laid down in the prescribed design data, without
consideration of the PC firing equipment. The number and arrangement
of the combined ignition and backup burners shall meet the
requirements of the PC burners.
The pulverizing and firing system shall be adaptable to varying fuel
qualities in such a way that on the one hand a stable firing of worse
fuel sorts is possible and on the other hand no slagging of the furnace
will occur when burning higher qualities of fuel.
Each ignition and backup burner shall be fitted with a pure gas-electric
ignition device and gas bottle station, its own flame detector, a
combustion air control damper and all other auxiliaries connections and
slop tank shall be provided.
Piping to the ignition and backup burners shall start at the inlet of the
isolation valve outside of the boiler area, be routed to all burners, and
shall contain all safety relevant equipment, fittings and burners valves
and accessories. For each burner, two quick acting safety shut-off
valves with intermediate drains to the slop oil tank shall be provided.
Explosion protection of the electrical equipment belonging to the coal
grinding and firing system shall be in compliance with the requirements
of the NFP A code or recommendations or other similar standards.
1.3.3.1 Coal bunker
Each pulverizer has to be fed from one coal bunker and one feeder.
The bunkers shall provide the necessary counter pressure by means of
a minimum coal level against the pressure in the coal mills.
The design of the bunkers shall guarantee a controlled, continuous and
undisturbed feeding of the mills. This should be achieved by giving a
due consideration to the properties of the stored and selected of a
suitable form and suitable outlet openings.
Each boiler unit has 4 coal bunkers. The bunkers shall be provided with
a total reserve corresponding to a minimum of 16 hours of operating at

MCR as "active content". The "active content" of
large as feasible, reducing the stagnant mass to a minimum.

the

bunkers

shall

be

as

The bunkers shall be properly integrated with the boiler steel structure,
presenting
an
overall
neat
appearance.
For
this
reason,
they
should
preferably be of rectangular or square form in plain view with pyramidal
hoppers.
The following recommendations should be followed for the section of the
shape of bunkers:
• steep sides of hoppers, with a minimum inclination of 75° to the horizontal
opposite
sides
having,
if
possible,
a
different
angle
of
inclination,
• bunker
discharge
zones
with
large
outlet
openings,
minimum
dimension of 1.0 m
• no
additional
constructions
between
outlet
openings
and
feeders
(maximum length of 2.00 m)
• round off with a minimum r = 600 mm at bunker edge.
The geometry of bunkers shall be satisfy the mass flow requirements,
taking into account the following:


kind/type of stored coal



properties of wall linings



number, shape and size of outlets and auxiliary outlet equipment



prevent coal dust emission.
All measures which are necessary to reduce the
arching and segregation of the stored coal shall be duly considered.

effects

of

funneling,

Carbon
steel
of
sufficient
abrasive
resistance
and
good
welding
properties shall be used for bunkers plates. Stiffeners and all supporting
steel shall he conform to the standard specification.
The
bunkers
shall
be
designed
with
unlined
considering no plugging and smooth coal discharge operation. '

inside

surface

by

The bunkers shall be designed to meet all applicable loads.
The bunkers shall have sufficient rigidity in order t 0 prevent distortion
during erection and to reduce bulging effects due to the stored coal.
A suitable allowance for abrasion and corrosion shall be used in
specifying the plate thickness.
It shall specify all loads required for the design of foundation and
adjacent
buildings.
Design
interfaces
shall
be
established
as
soon
the structural concept is established.

of
as

For the determination of the auxiliary outlet equipment, such as shut-of
rods,
assisting
equipment
for
coal
flow-out,
conveying
elements,
etc.
increased reliability margins shall be considered.
The bunkers shall be of welded steel construction.
Due attention shall be given during erection to the following items:


interfaces with the construction of foundation



interfaces with the construction of adjacent buildings and structures



sequence of erection (welding)



erection tolerance.
Bunker emptying facilities are to be provided. These shall consist of:


A
permanent
mild
steel
chute
extending
form
underneath
each
feeder, through the operating floor to a position just above the mill
cranage runway beams. The cute shall be positioned so that coal in
the feeder will reach it before reaching the discharge opening in the
mill.



A needle weir at the entry of each permanent chute. This will be in
the close position for normal operation of the feeder. A blanking plate
shall also be provided at the end of the- chute.



One
motor
bunker outlet.



A
temporary
chute,
for
attachment
to
the
permanent
chute
and
extending from the permanent chute to a position in the mill aisle
convenient for direct discharge onto a lorry. The chute shall be made
from mild steel except for the least 2 m of the chute which shall be of
a reinforced rubber to facilitate even distribution on the lorry.

operated

slide

gate

valve

It is envisaged that only one bunker will
therefore only one temporary chute per unit is required.

shall

be

be

provided

emptied

at

a

at

time

each

and

Gallery access for coupling the temporary chute shall be provided.
The bunkers shall be provided with probes to actuate
tripper conveyor and belt trip with indication in the coal
panel and also a high level alarm.

automatically a
handling control

Each bunker shall also be provided with low level detectors
position
on
the
centralized
control
boiler
annunciator
warning lights and alarms in the coal handling panel.
Suitable coal anti-bridging devices shall be provided such as vibrators.
For the chutes from the bunker to the pulverizers

to operate a
and
operate

a

pneumatic

deblocking system shall be provided. In addition the chutes shall be
provided with breakaways (gradual enlargement to relieve lateral
pressure and pipe friction).
The bunkers shall be provided with an C02 fire fighting system.
1.3.3.2 Coal feeders
The raw coal is to be fed even distributed to the centre of the mills by
means of encapsulated plate conveyors. The coal feeders shall be
designed dustproof and pressure-tight (gauge pressure of 0.5 bar). The
coal feeders are to be designed with enough margin in capacity compared
with the coal mills.
All sides of the casings of the plate conveyors - including the shaft ducts
must be absolutely tight against dust escape. The front and side walls, discharge box must be at least 4 mm thick. The scraper floor must have a
thickness of 8 mm or more.
It is to be ensured by means of the suitable choices of coal bed thickness,
conveyor speed and paddle shaft speed that coal feeding is effected
continuously in every load range. The .coal feeders have to be equipped
with an coal bed thickness indicator.
The plate conveyor is to be of a solid and wear-resistant construction so
that it can be operated throughout its entire service life without constant
repair work being necessary.
In order to prevent corrosion to the roller chains of the coal feeders, an air
seal supply with gate valve is to be connected at the outlet of every coal
feeder. Pipes and valves belong to the scope of supply of the Contractor.
Steplessly variable drives with
variable speed transmissions.

remote

adjustment

are

to

be

provided

as

The coal damper, coal fall shaft in the feeder discharge section and the
bunker passage to the feeders are to be lined with stainless steel.
In addition, the mill feeders are to be equipped with needle weirs, height
levelling

frames

(stainless

steel)

coal

bed

thickness

controllers,

pendulum

plate, tension station and automatic oil Iubrication equipment of for the
conveyor, paddle and scraper shafts, Belt or chain cleaning device, one
inspection door (0.5 m x 0.5 m) above coal feeder and at front and rear
side, chutes between feeders and mills, complete scraper equipment and
complete air seal equipment. \
Dumping of coal from the feeder to the mills shall be done vertically or

227

nearly vertically.

1.3.3.3 Coal mills/pulverizers
The pulverizers and the firing plant shall match the boiler plant overall
layout and shall be designed so that all operation requirements including
start-up and shut-down, also transient at turbine trip, emergency boiler
shut down, or failure in the internal power supply can be covered safely
and without damage.
The coal pulverizer shall be
conjunction with primary air fan.
The pulverizers
(separator).

shall

be

suitable

equipped

with

for

pressurized

adjustable

operation

classifier

in

system

The system shall operate as a continuous process and, within the
specified design limitations, the coal feeding shall be varied as rapidly
and as widely as required by the combustion process.
It shall be possible to be operated the pulverizers and firing plant stable
and safely between 30% and 100% boiler MCR.
At all partial load conditions it shall be assured that each burner has the
same and controlled fuel/air ratio.
The coal supply, pulverizing and burning system shall be arranged as
independent path from the bunkers, coal feeders, pulverizers, pipe work,
to the burners.
The pulverized coal system shall be supplied completely with
accessories as specified and as required for a complete unit and to
secure safe, reliable and efficient operation.
The pulverizer shall be of Low speed Horizontal Ball mill (2 inlet 2 outlet)
type of proven design and of pressurized operation type. Coal mill shall
be designed by considering Coal Hard Grove Grindibility index (HGI) 75.
The feeding of the coal into the pulverizer shall be centric through the
classifiers. Each pulverizer has to be equipped with an automatic
operating steam smothering system.
Manhole covers and inspection hole covers at pulverizers and fans shall
be designed so that absolute dust tightness can be guaranteed. The
inner mill casing has to be manufactured without dead comers.
The pulverizer gear shall be easily exchangeable in such a way that
during necessary gear repair an exchange of the gear is possible
without dismantling important parts of the pulverizer casing.
All pulverizers shall be equipped with adequate and insert gas protection
fire-fighting system by steam.

If pulverizers and feeders are stopped
again shall be possible without previous cleaning.

by

an

electric

failure,

The mills shall be designed in such a way that
rearmoured within a short time on the spot and that all
also be executed.

they
other

starting-up
can easily
repairs can

It shall be possible to isolate the mills from the hot air/gas ducts and
from the dust ducts in such a way that the boiler operation will not ~e
disturbed when isolating one mill, and that maintenance work such as
rearmouring has not to be done under hard conditions. Doors of the
pulverizers
shall
be
provided
with
hinges
and
quick
acting
opening
dosing facilities.
Pulverizer
maintenance
and
operation in a quick and safe manner.

repair

shall

Boiler MCR shall be possible also
the related burners shall be cooled sufficiently.

during

be
failure

possible

during

plant

of

one

pulverizer

without

fuel

oil

and

The main criteria for the pulverizer design has to be


3 mills at design coal for MCR



4 mills at worst coal for MCR.
These operation
service.

conditions

Particular guarantees
wear
and
erosion
quantities).

shall
(the

shall

be

possible

firing

in

be given for all pulverizer parts subject to
guarantee
period
is
based
upon
stated
coal

All parts subject to wear and tear shall be so designed that an exchange
of worn-out parts shall be possible (easy access), even while boiler is in
operation.
After
the
guarantee
period
of
pulverizer
parts,
subject
to
wear
erosion,
the
pulverizer
capacity
throughout
may
decrease
by
maximum of 10%.
Suitable
measures
shall
be
taken
to
prevent,
under
conditions, each part of the mill being endangered by over temperature.

all

and
a

operating

The gear shall be of the totally enclosed type.
Each mill shall
oil cooler, oil
pumps.

be provided with its own lubrication
tank with heater, duplex filter and

Sealing air connections and seals shall be
and on the mill casing in order to protect
of dust.

oil system, including
double capacity oil

provided on
the bearings

the mill journals
against the entry

1.3.3.4

Pulverized coal burners (PC burners)
Type, number, arrangement and size of the PC burner shall be selected
by
the Contractor.
The pulverized fuel burners shall be designed in such a way that a good
mixing of dust coal and combustion air as well as a safe ignition of the dust
coal will be achieved.
The arrangement and alignment of the burners shall ensure an even temperature profile of the flue gas leaving the combustion chamber.
The PC burners shall be selected such to comply with the properties of the
coal and shall match the pulverizing system. It must be adequate for an
optimum combustion with due consideration to the furnace dimensions in
order to keep the NO x emission to a minimum and to avoid excessive
fouling.
Pulverized coal pipes and burners as well as burner installation shall be
arranged to guarantee easy dismantling of the burners and other wear
parts. Erection and dismantling devices shall be provided by the Contractor.
It has to be shown by reference plants or in a flow test plant that a perfect
flame distribution and combustion quality for the total coal range and all
loads can be guaranteed. Sufficient possibilities of air regulation during
operation are to be provided.
Each burner shall be provided with its own lighter and flame scanner. The
burners shall be robust and shall stand long operation periods. Adequate
measures shall be taken to protect coal burners which are not in operation
from being damaged by radiation of heat coming from the furnace.
Each coal burner has to be equipped with thermocouples to measure the
burner mouth temperature if burners are out of service during boiler option.
Relative movements between coal burners and furnace walls shall be
compensated without that excessive forces act upon the burners and
without that false air penetrates perceptibly, into the furnace.
The supporting steel structure of the burners and the appropriate coal ducts
shall be designed so as to serve simultaneously for the suspension of lifting
devices required for assembling and dismantling of burners and ducts.
Selection of type of coal burner shall be made also under consideration that
simultaneous operation of the steam generator with coal and with diesel
fuel oil will be possible.

1.3.3.5 Distribution of pulverized coal
Pulverized coal pipes from the mills to the burners shall be arranged in
view of maximum symmetry to achieve even distribution to all burners.

The individual pulverized coal pipes behind the distributors shall be provided with shut-off devices which upon shut-down of one mill shall be
closed for avoiding the recirculation of hot flue gases.
Each coal pipe has to be equipped with air sealed test opening (approximately 500 mm in diameter) to extract pulverized coal for measurement
of grain size and coal distribution. Provisions for galleries in this area
are to be made.
The dust coal pipes from mills to burners shall be as short as possible
and arranged as straight as possible.
Changes of mills load shall not cause any disturbance of the gas and
coal dust flow in the pipes.
Pulverized coal pipes shall be from steel piping or sheet with sufficient
wall thickness and all necessary protection measures against wear and
tear. Each PC pipe has to be equipped with two coal extraction studs for
sampling. The extraction studs have to be equipped with an air sealing
device for preventing the PC leaving the PC pipes during sampling.

1.3.3.6 Primary air fan (PA fan)
To boost the pressure of the primary air, two radial fans with motors are to
be provided to extract cold air from behind the FD fans. Both of the radial
fans are to be designed for a mass how of at least 10% more than the MCR
primary air mass flow.
The requirements for noise protection stated in Section B06 and B07 shall
apply.
Control shall be effected via adjustable vane inlet controller(s).
Fan vanes shall be made in welded construction. The drive shaft shall be
dimensioned to withstand the critical speed by far.
Impeller wheel and shaft must be statically and dynamically balanced.
Bearing, coupling, seal and fan with spiral housing including accessopening in the housing are to be split; the dismantling of the impeller wheel
must be possible without great difficulty; the motor, bearing and fans are to
be set up so as to be vibration-dampened; there are to be suction and
discharge connections, vibration damper and all necessary measuring
equipment, etc.
Furthermore, there are to be suction
insulation casing and transition pieces.

and

discharge-side

silencers

with

Scaling air fans
The delivery head should be sufficient so that no pulverized coal can
leave the pulverized coal area into bearings, atmosphere, etc.
1.3.3.7 Inerting system for pulverizers and coal pipes
Special care is to be taken to avoid explosions inside the pulverizers
and coal pipes, especially when burning coal with a self-ignition
temperature of 220°C and high volatile matter.

The provision of the plant with an inerting system will be mandatory. The
offer shall consider an inerting system based on nitrogen, CO2,
inertisation with steam or flue gas (according to the manufacturer's
standard and for experience).
1.3.3.8 Start-up and backup firing system operating on diesel fuel oil
The diesel oil system will be used for boiler start-up and backup firing up
to 35% MCR boiler load.
The diesel oil system to be in accordance with TRD 411 or other similar
standards shall be completely up to the burners comprising following
main items:
•diesel oil burners with burner stations in groups, integrated in the
centre of the PC burners with oil return system .

filtering, pumping station, tank with unloading station and integral
piping for diesel oil, including control valves

flow measurement devices for supply and return pipes motor driven
main shut-off valve arranged at the end of the oil supply ~ pipes
(before distribution to the burner stations.
Type, number, arrangement and size of combined coal - diesel oil burners
shall be selected in such a way as to cope with the above requirements.
Each combined coal diesel oil burner has to be equipped with ignition and
cooling air supply, high energy spark plug ignitor and all necessary valves,
dampers and flame detectors.
Openings for burner lance, flame detectors, ignition Iance and inspection
peep holes are to be provided.
Each burner has to be equipped with an adjustable airswirl vane assembly
for optimizing the flame shape.
Burner shall not be subject to any deterioration by radiant heat when out of
operation. Therefore oil guns and ignition equipment shall be pneumatically
retracted in cooling position. A separate cooling air system has to be
arranged for cooling the burners, which are out of operation.
Flame detection system (IR/UV receiver) shall be of the self-checking
design. Start-up and shutdown shall be realized by a sequence programme.

232

Each valve combination for diesel fuel oil has to be carried out as duplex block
and bleed valve set.
The fuel oil strainers shall be of the cage type with a maximum gap width of 0.5
mm on the suction side and 0.08 on the pressure side.
The strainer assembly shall include integral flow switching gate valves, external
valve position indicators, differential pressure gauge, steam tracing and valves
for drains and vents.
The oil pumps shall be of the rotary screwed type. The horizontal pump units
shall be coupled directly to the driving motor. Each pump shall be fitted with a
pressure relief valve preventing over-pressure in the pump casing. Pump and
motor shall be mounted on a common base plate.
Spindles of the pumps shall be approved material nitrided and ground. The
design of the pumps shall take into account the increased oil temperature in the
casing.
The pump casings shall be at least of cast steel. Cast iron is not acceptable.
The pumps must be designed and suitable both for continuous or intermittent
operation. They must also be ready for immediate service even after a
prolonged period of standstill, without any special measures being necessary.
Suitable cleaning and drain piping of the systems to the slop-tanks have to be
supplied.
The arrangement of the whole equipment shall allow access to all valves and
instruments.
Integral piping for diesel oil, cooling air and compressed air shall comply, with
the requirements of this specification.
Besides the remote control system it shall be possible to operate the burner
from local box near the burner with minimum employment of the remote control
system. The change-over from remote control to local control shall be done by
key switch for each burner located on the control room panel.
The remote control system and the interlocking system as well as the closed
loop control shall be provided under Chapter B9 in these Tender Documents.
Therefore the firing system also shall meet the requirements of Chapter B9
(Instrumentation and Control Works).
1.3.3.9 Diesel oil storage tank and unloading station





All the equipment for the diesel fuel oil system shall be of the outdoor design.
Scope of supply/ installation shall include but not limited to the following:
One (01) diesel oil storage tank (tank capacity 2000 m 3);

Diesel oil unloading station [Two (02) diesel oil unloading pumps including
valves, pipings, filters and others as per requirement];
Interconnection with the existing diesel oil system.

Basically the tanks shall be designed in accordance with the requirements of
API
Standard
650
or
an
approved
equivalent
standard.
If
the
specification
contains
requirements
beyond
the
requirements
of
the
above
standard,
the
requirements of the specification shall have priority.
The tank roofs shall be of the self-supported cone roof type.
To prevent any damage to the tanks by storms, they shall be
If stiffening rings will be necessary, they shall be arranged inside of the tanks.

reliably

stiffened.

The specific gravity of all tank contents shall be considered with 1,000 kg/m 3.
Corrosion allowances shall not be provided for the tanks.
The tank bottom
slope of at least 1 %.

shall

be

pitched

downwards

conically

to

the

outside

with

a

Around the inside tank perimeter two drainage sumps shall be provided. Each
sump shall be equipped with a 50 mm diameter drain pipe connected to the
shell double flange nozzle. A shut-off valve with a blind flange shall be provided
outside the tank.
All flanges at the tank shall meet the requirements of the piping
in
Section
B06
General
Technical
Requirements,
Mechanical
flanges shall be of the welding-neck type.
All connection and spare
outside of the tank. All
outside the tank.

nozzles shall
spare nozzles

systems set out
Equipment.
The

be provided with flanges inside and
have to equipped with blind flanges

The fill nozzle is to be designed as a roof unit. A bend pointing on to the- tank
wall is to be flanged on to the inside of the tank so that incoming oil ' flows
tangentially to the tank wall. Care must be taken to ensue that the bend is
located with about half its effective section above the highest liquid level. A
baffle plate is to be provided at the tank wall.
All other nozzles - with the exception of ventilation and sounding hatch and the
return nozzle of the heavy fuel oil tank - are to be arrange din the lower shell
course.
Shell
manholes
are
to
be
equipped
with
hinges
(davits). A safety device
prevention unintentional closure of the cover is also to be provided. The clear
diameter of all manholes (shell and roof) shall be 600 mm at least.
A shell spiral staircase shall be furnished from grade
intermediate platform is to be arranged at half the tank height.

to

the

top

of

the

tank. An

Two roof vents shall be provided and each shall be designed for 100% capacity
to pass air so that at the maximum possible flow rate of the oil, either entering
or leaving the tank, excessive positive or negative pressure will not be

developed. The vent intake shall be protected by a screen with a mesh width of
not more than 5 mm. The clear screen area shall be at least 125% of the vent
nozzle area.
A 100 mm high kick-plate, tightly welded around the entire tank perimeter and
acting as a gutter is to be arranged on the tank. top edge. For each tank at
least two rain downpipes, connected to the kick-plate and provided at their
bottom ends with a 45° bend, are to be provided.
Each tank. is to be equipped with a device for local and remote level indication.
All level indicators at tanks shall have scales which indicates meters and
millimeters. Corresponding volumetric tables must be made available also. This
device shall be equipped with at least three adjustable limit contacts to initiate
alarms or signals at given levels (low, high, maximum).
Each tank shall be provided with an overfilling protection device (level switch)
which shall respond when the maximum permissible level is exceeded by
initiating an alarm and switch off the filling- pump of the oil truck.
The maximum limit contact of the level indicator shall also protect the tank from
overfilling by initiating an alarm.
The surface preparation, interior and exterior coating application, shall be done
in accordance with the requirements set out in Chapter BO "General Technical
Specification". Inside painting shall be applied only to the tank bottom and one
meter height of the shell above bottom.
In the dimensioning of all attachments on the outside of the tank,
sockets, manholes, measuring instruments, etc., allowance shall be
an insulation layer with a thickness of approximately 100 mm. The
shall meet the requirements set out in Section B06 (General
Requirements).

such as
made for
insulation
Technical

A pipe extending 2 - 3 m into the tank is to be flanged inside on to the bottom
discharge connection piece. The end of the pipe is to be provided with a bend.
The bend shall extend into a pour-in bowl, the upper end of which shall
terminate at the level of the sounding plate. The clear inlet area. of the pour-in
bowl shall be at least 2 times the outlet nozzle area.
1.3.3.10 Slop oil tank
The slop oil tank may be supplied wither as rectangular tank or as a horizontal
cylindrical tank. All necessary connections, manholes, drains and ventilation
systems are to be provided where required and made easily accessible.
The tank is also to be equipped with a local contents indicator having a sensor
arrangement to issue an alarm when the tank is full. Also to be provided is a
further level switch arranged to sever as dry-running protection for the pump
and to annunciate when the tank is empty.
1.3.3.11 Filters
For the diesel oil pump group, one duplex filter shall be provided on the
suction side.
The duplex filter shall be equipped with a change-over
change-over under full load conditions without operating trouble

device

which

allows

Each slop oil pump shall be protected by a single filter arranged in the suction
line. Each filter shall mainly consist of the filter bowl with cover and removable
filter insert.
All the filters shall be fitted with a differential pressure indicator equipped with
transmitters for electrical remote indication and alarm.
Filter covers are to be fastened by hinged bolts.
Filter bowls are to be equipped with stripping connections and valve.
Consideration is to be given to
initial pressure drop as low as possible

maximization

of

useful

screen

area

to

keep

The switching point of the differential pressure gauge shall be freely settable
Filter casings must be at least of cast steel. Cast iron is not acceptable
1.3.3.12 Pipelines, foam pourer
The pipelines shall be designed according to the requirements of Section B06
(General Technical Requirements).
A pipe emptying system shall be provided for the entire pipework system, so
that pipes which are out of use for longer periods can be emptied and do not
require continuous heating.
Each foam pourer is to be allocated a foam generator which shall be fitted in
the immediate vicinity of the foam pourer.
The foam generators and foam
resistant and heat resistant materials.

pourers

shall

be

made

of

process

water

The foam system for the oil tank shall be capable for foaming the complete
internal surface of oil.
Components made of plastic, plastic coatings, rubber or other materials which
in the event of fire, as a result of the effect of heat could prejudice the operation
of the foam generators or the foam pourers must not be used.

The pipes and valves of the foam system shall be made of corrosion resistant and heat resistant materials. Stainless steel or approved equivalentmaterials shall be
used.
The
nominal
pressure
of
the
foam
system
should
with adequate reliability be above the maximum possible operating pressure.
1.3.3.13 Electrical, control and monitoring equipment

The diesel oil pumps sl1all be controllable from the auxiliary panel in the
central control room. Indication of operating conditions, must, however,
also be available at the local control board.
Oil levels of tanks as well as all hazard, fault and monitoring information
from tanks, filters, pumps, etc., must be clearly arranged and recognizable
in the central control room.
The foam system shall work automatically by means of push button
control in the central control room.
1.3.4 Auxiliary steam boiler (if required)
Existing 2 x 125 MW units have 1 (one) 10 ton/ hr capacity auxiliary steam boiler.
If these capacity is not enough for the proposed 250 + 10% MW unit, then 1
(one) auxiliary steam boiler is required.

The auxiliary steam boiler fired with diesel fuel oil has to be provided if
necessary to supply steam to the steam turbine unit during the start-up
period. For an outdoor installation a respective weatherproof implementation has to be foreseen.
The number, type, capacity, steam parameters
auxiliary steam boiler shall be decided by the Contractor.

and

arrangement

of

the

Demineralized water will be used as boiler make-up water which is supplied
from the demineralization water plant.
The boiler used as the auxiliary boiler has the characteristics of frequent
start-ups, large changes of load, quick start-up, long periods between
maintenance, start-up at any time and operating reliability; being a
packaged completely assembled and then dispatched to site.
Because of characteristic difference between start-up boiler and normal
boiler, the water of this boiler can be drained completely and a nitrogen
blanketing protection connection shall be provided.
The plat form and gallery of boiler shall possess enough strength
stiffness shall be proved at operation, monitoring or maintenance locations.

and

The boiler shall be provided with the necessary observation ports, manhole
for maintenance and explosion vents.

The drum shall be provided with safety valve, vent valve, exhaust pipingand a motor driven
valve,
and
a
silencer
shall
be
provided
at
the
outlet
header of the superheater.
Connections for drum water level and furnace pressure measuring shall be
provided. Local instruments and remote instruments (in the control room)
shall be used for drum water level measuring, and the pressure,
temperature and flow rate shall have indications in the control room.
The boiler shall be provided with one set of forced draft fans, feedwater and
oil pumps. The steam pipe lines of the auxiliary boilers shall be connected
together and also with the extraction of the steam turbines. So that it is
possible, while the auxiliary boilers are shutdown, to start-up the second
steam turbine by the first, which is already in operation.
1.3.5 Inside cleaning of boiler pressure parts
After erection of each boiler the manufacturer shall perform boiling out and
blowing out as a protection measure. If necessary, the boilers shall be
passivated after this procedure. No acid cleaning measure is required but the
coal fired boilers themselves must be designed and fabricated in such a way
that an acid cleaning process can be carried out if required by the Purchaser.
If it will be found out after boiler erection that the inside tube and header
surfaces "are rusty and dirty, acid cleaning of boiler and all other equipment will
be carried out by the supplier without any costs for the Purchaser.
The criteria for above decision are as follows:




drum and headers are to be visually clean without any corrosion
cut tube samples may not have more than 0.11 mm corrosion layer or 15
mg/cm2 corrosion layer
recommended steam quality for starting up shall be reached within 2 - 3
days.
At least three months before the date fixed for the internal cleaning, the boiler
manufacturer shall submit to the approval of the Purchaser a complete and
detailed specification of the procedures that will be carried out giving all
sequential events and chemical analysis required.
The contract supply shall include for the boiler all necessary connections,
valves, fittings, etc. required for acid cleaning which might be required after a
certain period of operation.
The temporary blow-off pipe and blow-off valve should have the same size as
the main steam pipe and main steam valve.
For boiler conservation before commissioning the Contractor shall provide all
necessary equipment, material and consumables to maintain the boiler parts in
a non-corrosive state in accordance with the offered procedure.

BPDB, Barapukuria Power Plant
Section B1: Steam Generator
Performance and Design Criteria

1. Thermodynamic Data

Minimum requirements
Unit

Data

Steam generator
Max continuous rating (MCR)

%

104 of turbine MCR flow

Steam pressure (abs.) at HP superheater outlet

bar

145

Steam temperature at HP supertleater outlet

0C

535

Steam temperature at reheater outlet

0C

535

Constant steam temperature forth. HP superheaters of 535 0C

MCR

60 -100

Constant temperature for the reheater of 5350C

MCR

70-100

Minimum load far continuous operation without back-Up firing

MCR

30

Max operating pressure at flue gas side of boiler membrane

mbar

+ 70

Load range firing with diesel fuel oil

MCR

0-35

Feedwater temperature at economizer inlet

0

approx.. 207

walls/ducts

C

Reheater (RH) Data at MCR
Steam mass flaw at Inlet
$team pressure (abs.)

It RH inlet

Steam temperature at RH Inlet

kg/s
bar
0

C

cold and hot reheat steam pa
"ammers shall correspond with
the relevant data resulting from
neat flow diagram of the turbine
model selected

Feedwater quality
Feedwater quality in line wtth "VGB Directives for boiler, boiler
water and steam from water tube boiler Operating at pressure of 68
bar and up (latest edition)
Chemical mode of Operatiion 1 alkaline as per VGB Directive

8.0 - 8.5

pH-Value

Flue Gas
• flue gas temperature It regenerative preheater outlet
• max. allowable flue gas temperature at ESP inlet for 10
min.

0

C

150

0

C

350

B1/FB1

BPDB, Barapukuria Power Plant

Minimum requirements

Section B1: Steam Generator

Performance and Design Criteria

Unit

Data

2. Performance in Service

Intended operating regime
operating hours per year
total cold starts per year
cold starts (after 48 h shutdown) per year
warm restarts (a1tsr 8 h shutdown) per year
hot restarts (after 2 h shutdown) per year

n/a
8500
10
30
100
20

Rate of load change
100%
load
00% load

(referred
(referred

to
to

MCR)
MCR)

CD

1

+1 +1

From
50
From 30 Start-up times

% MCR/ min
% MCR/ min

Planned start-up times from cold condition up to 450 0C

and 70 bar

h

4

In order to achieve this start-up time and very short start-up
times for warm and hat restarts, the shortest possible
start-uptimes for the steam generator shill be stated in the
corresponding data sheet. Moreover the corresponding
start-up curves shall be submitted, in which also the
relevant boundary conditions shall be stated.

For rolling the turbine generator. initially minimum
steam conditions as follows shall be assumed:

Cold start
from OC/bar 50/1.0
up to OC/bar 450/70

min

Warm start from OC/bar 300/50
to OC/bar 500/100

min

Hot Start from OC/bar 450/120
to OC/bar 535/145

min

Precise start-up conditions will be established after
ordering the steam turbine generator jointly by the boiler
and the steam turbine generator suppliers, with the
permissible gradients of the steam turbine generator
being taken into account by the contractor in his own
start-up curves.

BPDB, Barapukuria Power Plant
Section B1: Steam Generator

Minimum requirements

Performance and Design Criteria

Unit

Data

m3/ h

400

mm

380 x 425

m/s

12

3. Design Construction Data
Boiler drum
The steam space loading shall be smaller than
The elliptical manholes at each end of the drum not less than .
Maximum saturated steam velocity In connecting tubes to SH
Economizer
Max. height of heating surface tube banks
Min. clearance between two heating surface tube banks with
access possibility and/or where sootblowers are installed
Type of tubes used
Type arrangement
Transverse pitch not less than
Longitudinal pitch not less than
Add-on reserve heating surface
Arrangement of access doors

m

1.8

m

1.2

plain tubes
in-line
100
80
10
on both sides
Directly
down
stream of

mm
mm
%

Support tubes/support tube granting
Preferred connection.
Pitch in first platen heating surface
transverse pitch not less than
longitudinal pitch not Jess than
Superheater (SH)
Max. height of heating surface tube banks
Minimum clearance betw8en two tube banks if access possibility
provided and/or where sootblowers Installed
Design of super heater

evaporator

mm

800

mm

60
m
m

pieces

2
inline
100/200

mm

longitudinal pitch SH l/ll not less than
Arrangement of across doors

mm

Add-on reserve heating Surface as margin
Max. permissible steam side temperature rise In the final super
heater

%

B1/FB3

1.2
2 pass 3
stages
crosswis
e

Arrangement of the connection pipelines between the SH stages

Number of required attemperators between superheater stages ll
and III
Plane tube arrangement
Transverse pitch SH l/ll not less than

1.8

0

C

55
on both
sides
10
75

BPDB, Barapukuria Power Plant

Minimum requirements

Section B1: Steam Generator

Performance and Design Criteria

Unit

Data

Reheater (RH)
Max. height of heating surface tube banks
Minimum clearance between two tube banks where an
access possibility is provided and! Dr where sootblowers are
installed
Design of reheater
Arrangement of connection pipelines between the RH stages
Number of necessary attemperators between reheater
stages I and II
Tube arrangement
Transverse
pitch
RH
I
not
less
than
Longitudinal
pitch
RH
I
not
less
than
Transverse
pitch
RH
ll
not
less
than
Longitudinal
pitch
RH
II
not
less
than
Add-on
reserve
heating
surface
Arrangement of access doors

m
m

1.8
1.8

2-pass
crosswise
2

pieces

mm
mm
mm
mm
%

in
100
70
400
70
10

line

on both sides .
The attemperator spray water quality corresponds to that of
the feedwater
PC direct firing
gas-side vacuum

Firing system, fuels
principle
Firing operated with
Main fuel

high volatile
bituminous coal
Annex

The fuel. specification shall be adapted for the design
of the boiler and its associated equipment according to

Note:
1. The boiler shall attain its MCR when firingng the coal
within the band with specified at any of the local ambient
conditions.
2. Optimizing of boiler design Shall be based on the guarantee coal.

Characteristics of coal ash according to
Fuel for ignition of coal burners
for cold start-up conditions

for warm start-up conditions and back-up firing
.diesel fuel oil
..net calorific value
Load range of ignition end back-up firing of MCR

Annex
MJ/kg
%

0- 35
42

BPDB, Barapukuria Power Plant
Section B1: Steam Generator

Minimum requirements

Performance and Design Criteria
Excess air
Maximum excess air in furnace. for coal firing (guarantee
coal) between 60 % and 100 % MCR.
coal bunkers
Number of coal bunkers
Design of the bunker cells and supporting structure

BPDB, Barapukuria Power Plant

Net storage capacity of bunker shall correspond to the coal
Section
SteamofGenerator
demand
forB1:
operation
Coal
feeder
Performance
and Design Criteria

Unit

Data

%

20

-

4

-

steel structure

Minimum requirements
operation
hours

Unit

or 1 single
fan: minimum
Range
of control,
Resistant up to pressure of
• capacity
Coal
preparation
and burning equipment
Other
data:

%MCR
0

• temperature of regenerative air preheater exit
Number of pulverizes an which the boiler has to achieve Its
MCR
Typewith any of the coals fired

C

Minimum
Type control
number of pulverizes In operation at minimum
load of the boiler of 30%.
Pulverizers
Ingestion temperature at design point

0

C

Type of drive
Minimum interval between two scheduled Overhauls of the
mills
■ -1
Maximum speed
Design
margins
of each pulverize:
Sealing
air fans
addition
of
wearMinimum number to-tear

min 1

Data
bar

inlet guide vane2
variation mechanism
30
electric motor (direct
hours
8,000
type)
1000
%one fan for each
10
%pulveriser.

%

110

Minimum
admissible velocity at pulverized coal/air mixture
• capacity

%

m/s121

Type
Pulverized coal burners
T ype of control
The capacity of an burners shall be such that the boiler
MCR
can be
malntainedat
with
one burner
Ingestion
temperature
design
point out of operation
(n-1)
Type of drive
Primary air fan

capacity
Firing capacity of ignition burners

B1/FB5

18

0

C

-1

min 1

inlet guide vane
variation mechanism
30
electric motor.(direct
drive}
1000

%MCR

%120 of fuel demand
110 at

%MCR

%35 % of MCR 121
35
n-1

achieve Its 35% MCR-Load
-

1:5

• delivery head

%

110

• capacity

%

121

Safety margins

B1/FB6

5

radial

Number of oil burners for which the boiler can
Minimum turn-down ratio of diesel fuel oil
burners/air system
Cooling and ignition air fans

60

1:5
3.5

design temperature +
n-1
5O 0K
radial

addition for control margin
Safety margins
Distribution
of pulverized coal
• delivery head

Maximum
speed
Safety
margins
for design
and back-up
firing system operating
2 Start-up
fans operating
in parallel:
on diesel fuel oil
deliveryof
head
Capacity
diesel oil pumps

24 at MCR

BPDB, Barapukuria Power Plant
Section B1: Steam Generator
Performance and Design Criteria

Minimum requirements
Unit

Data

Hot reheat temperature at
• 100% MCR

0

C

• 60% MCR

0

C

• MSL

0

C

Range of constant reheat steam temperature
Feedwater temperature at
• 100% MCR

%MCR

0
0

C
C

• 60% MCR
Superheater spray water flow at

kg/s

• 100% MCR
• 60% MCR
Reheater spray water flow at

kg/s
kg/s

• 100% MCR
• 60% MCR
Coal consumption for
100% MCR
Boiler efficiency based on HHV for
• 100% MCR
• 60% MCR
Air temperature at pulverizer inlet at

kg/s
t/h

%
%
0

C

0

C

• 60% MCR
Flue gas temperature (uncorrected) at stake inlet at

0

C

• 60% MCR

0

C
C

100% MCR

oo
oo

Flue gas temperature at furnace outlet at
• 100% MCR

0

• 100% MCR
Excess air in furnace at
• 100% MCR
• 60%MeR
• MSL
B1/FD1

%
%
%

BPDB, Barapukuria Power Plant
Section B1: Steam Generator

Bidder/Contractor

Unit

Technical Data by the Bidder

Data

All design data of the data sheets refer to the MCR
conditions and are based on guarantee points, the
design coal and the reference data (Basic Design
Conditions according data sheet BO/FB-1) if not
otherwise stated.
BPDB, Barapukuria
Power
Plant
General
information
Section B1: Steam Generator
Section B1: Steam
Generator
Type
of boiler
Technical
Data by the Bidder
Manufacturer
Technical Data by the Bidder
Design
code1for
pressure part
Reheater
Inlet

Bidder/Contractor
-

Unit

Unburned manner in raw gas dust at 100% MCR100% MCR
Design standard
Reheater
1 outlet
for material
Max. unburned matter in bottom ash/slag at 100% MCR

Unit
Data
- 0C

%

- 0C

%

Attemperator 3 outlet

Summarized
data
Number of pulverizers
in operationperformance
for

Reheater 2 outlet

• 100% MCR

pc.s

Fuel: High volatile bituminous coal
Flue
temperatures
(grossgas
calorific
value 26,000 kJ/kg)

• 60% MCR

0

C

0

C

0

C

pc.s

Combustion chamber outlet

Heat load of boiler at
After
supemeater
3
• 100%
MCR
Throughput of one pulverizer
After reheater 2
• min. stable load (MSL)
Operating data
live steam
flaw at 2
After
superheater

pc.s

• MSL

0

MWC

kg/h

0

C

MW
0

C
kg/s
0
C

• 100% MCR

Note:

Bidder/Contractor

After reheater 1

• 60% MCR
All data refer to MCR
andsuperheater
guarantee conditions
After
1

kg 0/s

• MSL

C

kg/s

Water/steam flows After economizer

0

C

Feedwater

After
regenerative
air preheater
Live steam
pressure (constant
over the whole load range)

kg/s

barC

Live steam

At stack inlet

kg/S

0

0

C

Live steam temperature
at
Operating
times
supemeater spray attemperator:
100%MCR
cold start
1 •Very
• 60% MCR

kg/s
(drum temperature equal with ambient temperature)
kg/s
• attemperator 2 • MSL
Time of preparatory measures (including time for heating
Reheater spray attemperator
kg/s
Range
constant
temperature
up
theofboiler
vialive
thesteam
deaerator)
up to first ignition
• attemperator

Water/steam pressure (absolute) at
Economizer inlet

bar

Time from ignition of first burner up to MCR

Drum /evaporator • 100% MCR
Cold
• 60% start
MCR (at ambient conditions)
superheater outlet
Time
• MSL from ignition of first burner up to MCR
Economizer inlet

bar
bar
0

C

Cold
temperature at
Drumreheat
temperature

0

C

Drum/evaporator

0

C

(after 8 hours shut-down)
• MSL
Drum
temperature
before start
Supporting tubes

C

min
%MCR

•Warm
60%MCR
start

B1/FD2

C

0

C

1 inlet Drum pressure before start

Superheater

C burner
1 outletTime of preparatory measures up to Ignition of first
0

burner to MCR

Hot start (after 0.5 - 2 hours shutdown)

Attemperator 1 outlet

Drum temperature before start
Superheater 2 outlet
Drum pressure before start

Atlemperator 2 outlet

0

C

0

C

0

C

0

C

C

C

min
0
0

0

C

min
kg/s
kg/s
min
kg/s

0

Superheater

C
C
0

C

bar
min
min
0

C

bar

Time of preparatory measures up to Ignition of 0first burner

min

Time from ignition of first burner to MCR

min

Superheater 3 outlet
B1/FD3

0

C
C

0

• 100%, MCR
Economizer outlet Time from ignition of first burner up to MCR

Attemperator 1 InletTime from ignition of first

0

0

Drum
temperature (after preheating)
Hot reheat steam flow at

Water/steam temperature
at (after 48 hours shut-down)
Cold start

0

B1/FD4

C

Data

BPDB, Barapukuria Power Plant
BPDB, Barapukuria Power Plant
Section B1: Steam Section
Generator
B1: Steam Generator
Technical Data by the Bidder
Technical Data by the Bidder
Steam drum

Minimum requirements
Bidder/Contractor
Unit

Data
Unit

Controlled load reduction after turbine trip at MCR

Manufacturer

Time from turbine trip up to operation of boiler al MSL
mm
Automatic control limits for steady load change
Internal diameter
mm
(Rate
of
load
variation
not
exceeding
1%
of
MCR)
Plate thickness
mm
HP steam pressure
Material of steel plate
Hot steam temperature
Volume of steam drum
m3
Hot
reheat
steam
temperature
Water volume up to normal water level
m3

min

Cylindrical length

Type of internals
Safety valves

±bar
±0C
±0C

-

Drum level

±mm
±%

Excess air

Automatic-control limits for max. load change gradients
Rate of load change
Type
HP steam pressure
Drum safety valves
HP steam temperature
Manufacturer

Number

%/ min
±bar
±0C

-

Hot reheat steam temperature

Capacity
Set pressure

Data

±0C

% MCR
Drum level

±mm
±%

bar

Excess air

Superheater safety valves
Technical particulars
Number
Capacity
Set pressure

Boiler steam/water system, Furnace
Projected heating surface
Volume of combustion chamber

Max.
heat release per unit related to:
Hot reheat line safety
valves
• projected heating surface
Number
• volume of combustion chamber
Capacity

"

m2

% MCR

m3

bar

MW/m2
-

MW/m3

% MCR

Set pressure

Distance of flame boundary from boiler wall tubesbar
Hot reheat steam blow-off
Numberstation
of risers (wall tubes)
Number
Material of risers
Capacity
% MCR
Riser outside
diameter
Continuous bailer blow-down
flash
tank x wall thickness
Cylindrical height Tube pitching of risers
Furnace overall dimensions:
Outside diameter

mm

Blow-down rate

kg/h

m
mmxmm
mm

mm

• height (mean) / width/ depth
Boiler drain flash tank
Water volume
Cylindrical height
mm
Volume
of
water
from
economizer
inlet
up
to
drum
center line
Outside diameter
mm
Flow rate

B1/FD7

Volume of total superheater

B1/FD5

BPDB, Barapukuria Power Plant
Section B1: Steam Generator
Technical Data by the Bidder
Steel structure

mxmxm
m3
m3

kg/h

Bidder/Contractor

Unit

Data

Manufacturer

-

Design code for static calculation

-

Estimated total quantity of steel for boiler

-

Platforms

Elevation of operating platforms

m

Elevation of auxiliary platforms

m

Boiler insulation and brick lining

Max. temperature at outer face of insulation

0

C

Total heat loss of boiler

kW

Design heat flux density

W/m2

Refractory lining material

Denomination (type)

-

Manufacturer

-

Max. service temperature

0

C

Operational life time

h

Components which will be brick lined

-

Bricksetting material



Denomination (type)

Manufacturer

-

Form of delivery

-

Refractories

Operational rife time

h

Components for which Bricksetting will be applied

Sootblowers

Number of blowing cycles per day

--

soot towers of SH

Numbers of sootblowers

pcs

Type
Soot blowers for economizer
Numbers of soot blowers
Type
Soot towers of RH
Numbers, of sootblowers
Type

pcs
-

pcs
-

BPDB, Barapukuria Power Plant

Bidder/Contractor

Section B1: Steam Generator
Technical Data by the Bidder

Unit

Data

Soot blowers for combustion chamber
Numbers of soot blowers
Blowing medium
Type

pcs
-

Coal preparation and burning equipment
Coal bunkers
Manufacturer
Number of bunkers
Type of construction
Material

pcs
-

Inner lining material
Thickness iron sheets
Capacity of each bunker

mm
t

Size of gate valve

mm

Chute material
Coal feeders
Manufacturer

-

Number
Type of construction

pcs
-

Capacity
Design coal density

kg/h
kg/m3
-

Operation range
Conveying width
Max. bed coal height
For withstanding an inside explosion pressure of

mm
mm
bar

Rated power

kW
-

Inner lining material
Chute material

Design
Coal

Coal mills
Number of mills
Manufacturer

pcs
-

Type / Model
Capacity per mill. max. after 3.000 operation hours

kg/s

Capacity per mill at MCR (n mills in operation)
Capacity per mill at MCR (n-1 mills in operation)

kg/s
kg/s

Fineness of grinding (oversize on 0.09 mm sieve at 550)

%

Temperature downstream of mill

0

Hot air mass flow rates per mill

B1/FD9

C

kg/s

Worst
Coal

BPDB, Barapukuria Power Plant

Bidder/Contractor

Section B1: Steam Generator
Technical Data by the Bidder

Unit

Data
Design
Coal

0

Hot air temperature at mill inlet

C

Pressure difference between primary air inlet and
separator outlet
Cold air mass flow rate per mill
Cold air temperature

mbar
kg/s
0
C

Power consumption at Coupling at MCR per mill

kW

Type of gear
BPDB,
Barapukuria
Plant
Weight
per mill
incl. gearPower
and motor
Section
B1:
Steam
Generator
Cooling water mass
Technical Data by the Bidder
Mill Inerting
drivingsystem
motor for coal mills and coal pipes and ducts
Manufacturer
Medium used for inertisation
TypeQuantity of medium required
Rating
PC burners
Rated voltage
Manufacturer
Speed
Type/model

t
kg/s

Primary
Number
air fans
of burners per boiler
Manufacturer
Pressure loss in the burner (air side)
of primary/secondary/tertiary air
TypeProportions
of construction

Bidder/Contractor
Unit

-

-

kg/h

kW

kV
min1

-/pcs
mbar

.

-

%

Coal flow rate per burner at MCR and design coal
Number
Capacity
each fan equipment
(m3 at 00C,type
1013 mbar)
Flameofdetection

pcs
m3/h

kg/s

TotalNumber
head of flame detectors
Weight per burner
Air temperature

mbar
0
C

pcs
t

Position or burners in furnace
Drive:
Diesel oil start-up and backup burners
• power
Number of burners
• speed
Manufacturer
Efficiency at MCR
%
Type/model
Seal air fans
Max. firing capacity per burner
Manufacturer
Total diesel fuel oil now rate at 35% of MCR
at burner inlet
TypeOil
of pressure
construction
Flame
Number
perdetection
boiler equipment type
Capacity
of each fan
(m3 at
00C, 1013
mbar
Manufacturer
of high
energy
electric
ignition equipment
TotalNumber
head of electric ignitors per burner
Air temperature
Diesel oil supply system
Drive:
Number of tanks
• power
Tank capacity
Tank diameter
• speed
Cylindrical height

-

kW
rpm

pcs
-

-/-

MW
kg/S
bar

pcs
m3/h
mbar
0
C

-

pcs
pcs
m3

kW

m
m

rpm

B1/FD10

Tank weight (empty)

t

Number of oil pumps
Capacity per pump
Oil pressure at pump outlet
Manufacturer of pumps
Type
Rating
Rated Voltage
Speed.
Pressure at control valve Inlet
B1/FD11

Worst
Coal

pcs

t/ h

bar
-

kW
kV
.1

min'
bar

Data

BPDB, Barapukuria Power Plant

Bidder/Contractor

Section B1: Steam Generator
Technical Data by the Bidder

Unit

Diesel oil slope tank
Cylindrical length

mm

Outside diameter x wall thickness
Tank capacity

mmxmm
m3

Diesel oil slope pumps
Manufacturer

-

Type
Number of pumps
Flow rate per pump

-

pcs

Kg/s

Diesel oil unloading pumps
Manufacturer
Type
Number of pumps
Flow rate per pump

B1/FD12

-

Kg/s

pcs

Data

Steam Turbine Plant

B2. Steam Turbine Plant
2.1 General
This specification covers the design, manufacturing and supply of one reheat
steam turbine generators with associated systems. Steam turbine generator is
rated 250 +10% MW.

2.2 Scope of Supply and Services
This section sets out the "scope of the installations covered by this
specification as well as requested supplies and services, but without
excluding other necessary components and services not mentioned.

2.2.1 Steam turbine generator
Steam turbine
1 (one) reheat condensing steam turbines complete, each one including at
least:


emergency stop valves complete, including the necessary blow-out
provIsions



steam strainers for installation in the emergency stop valves or including
housing for installation in the live steam line and reheat line



electro and hydraulically operated control valves at the inlet part of the
HP section of the turbine



electro and hydraulically operated combined or separate intercept!
emergency stop valves before the IP section of the turbine



hydraulically operated control valves for LP-steam admission


check valves and motorized isolation valves for LP bleed to the deaerator/feedwater tank



motorized turning device, complete, with manual turning equipment



gland steam system complete with gland steam condenser



complete noise and heat insulation



turbine enclosure, complete



fire protection equipment .




all connecting piping, fittings, safety devices, fastenings,-etc.
static and dynamic calculation or the turbine foundation (including
deflection calculation due to occurring forces and moments).
Turbine oil plant
Lubricating and control oil plants for the turbine generator complete. including at least:

• oil tank including oil strainers
• main oil pump preferably direct driven"
• auxiliary oil pump (100%) with AC motor drive
• emergency oil pump with DC motor drive







jacking oil pumps one with AC, one with DC motor drive (if applicable)
control oil pumps with AC motor drive (if separately necessary)
oil vapour extraction fans with AC motor drive with oil separation in the piping
oil coolers
double oil filter for the complete lubricating oil flow
double oil filter for the complete control oil flow
•all connecting piping, fittings, non return valves. safety devices. fastenings., supports of
the oil system. Sheet metal ducts for oil piping and other oil spray protection equipment.
• connections for mobile purification plant
'.
• 1 (one) common mobile oil purification plant for all turbine oil systems
Waste oil disposal system
Drains for oil tanks, oil coolers, etc. to liquid waste basin including all required piping,
filters, valves, instrumentation etc.
Downtime Ventilation Plant
1 (one) transposable downtime ventilation
complete with air drying plant, etc.

plant

to

avoid

down

time

corrosion,

Condenser
2 (two) condensers, complete. with spring sponsor expansion compensators on the
on the steam duct, with hotwell, condensate level control etc., each including at
least:
• vacuum breaking device
• all connecting piping, safety devices, fastenings, etc.
• 1 (one) steam/air ejector for start up complete.

2 (two) evacuation units for the steam side with steam/air ejectors, complete
with vacuum condensers, piping, valves, fastenings, etc,.


evacuation connections to vacuum parts of the plant complete with piping,
valves etc.



3 (three) half load main condensate pumps complete, each with motor drive
and minimum flow device.



Automatically controlled condenser sponge ball cleaning system with
automatic sorting & and counting of the balls, complete including screens,
ball circulating pumps, connecting piping, fittings, fastenings, local control,
monitoring and switchgear equipment, etc.

Turbine bypass stations
Separate HP and IP steam bypass stations (each bypass line equipped with

1 (one) emergency stop valve and 1 (one) reducing valve), complete with the
associated actuating and control equipment, piping from the station(s) to the
cold reheat line/to the condenser and from the feedwater/main condensate
line to the injection points.
Control and monitoring equipment
All control, governing, measuring and monitoring equipment, instrumentation
necessary to match particular design arrangements of the apparatus and
units, including


electro-hydraulic turbine governor



jump and rate limiter



monitoring and protection system complete



instrumentation and monitoring
Generator and electrical auxiliaries



1 (one)
follows:

synchronous



internal closed-cooling cycle with air-to-water coolers (incl. one stand by
cooler) as preferred solution, or alternatively



internal closed-cooling cycle with water cooling directly through stator
winding and rotor winding and internal closed-cooling cycle with air-towater coolers (incl. one stand by cooler) for remaining parts,



complete compounded excitation system (static or brush less rotating
system) (the Bidder shall mention the reason why he did choose what)
and A VR with power factor control,



generator control panel,



generator star point and terminal cubicles,



complete generator busducts up to generator step-up transformer and unit
auxiliary transformer, including isolators, surge arrestors, voltage and
current transformers, etc.,



generator and unit protection,
monitoring equipment,

synchronization,



associated
etc.

CO 2

equipment

AC

generator

including

with

fire

complete

cooling

measuring,

protection,

metering

pipework,

2.2.2 Feedwater pumps
For steam generator 3 (three) feed water pumps , 62.5% capacity each
including flow control devices, two in operation and one as stand-by,
complete with electrical drive, nonreturn valve, hydraulic fluid coupling t
base plates, drive motors etc. and speed increasing gear.
For each pump set:

system

as

and

control




1 (one) complete minimum-flow system including minimum-flow valve,
flow measuring device, start-up line etc.
3 (three) booster pumps complete (if applicable)
Control equipment and monitoring equipment
All necessary local and remote instrumentation control and monitoring
equipment with a scope at least conforming to the corresponding
descriptions plus further instrumentation needed for adaptation to
special versions of equipment.

2.2.3 Feedwater heating system
For power unit to be supplied at least:
Combined deaerator/ feedwater tanks
1 (one) feed water tank with deaerator complete, with supporting structure
all stub pipes, stiffeners, baffle plates, steam heated stand pipe, separate
warming up steam line strainers upstream the deaerator spray nozzles,
vapour extraction system etc.
HP feed heater 6
1 (one) HP feedheater complete with supporting structure, fastenings,
connection branches, safety valve, level indication, condensate level
control
HP feed heater 5
I (one) HP feed heater complete with supporting structure, fastenings,
connection branches safety valve level gauge condensate level control
HP-feed heater emergency bypass system and condensate emergency
drain control
LP feed heater 3
1 (one) LP feedheater, complete with supporting structure anchorage, level
gauge and condensate level control, etc.
LP feed heater 2
1(one) LP feedheater, complete with supporting structure, anchorage, level
gauge and condensate level control, etc.
LP feed heater 1
1(one) LP feedheater, complete with supporting structure, anchorage, level
gauge and condensate level control, etc.

Separate desuperheater (if applicable)
1

(one) HP desuperheater for HP feedheater, complete with supporting
structure, etc.
Control equipment and monitoring equipment
All necessary local and remote instrumentation control and monitoring
equipment with a scope at least conforming to the corresponding descriptions plus further instrumentation needed for adaptation to special versions
of apparatus and equipment.

2.2.4

Piping, insulation
Piping, valves and accessories
All required piping as far as not included in the other sections (as e.g. steam
generator plant, water treatment systems, auxiliary systems) including all
accessories such as drains, vents, valves, safety devices, steam traps,
condensate drainers, strainers, actuators, pipe supports, anchor points,
expansion joints, nozzles for instrumentation and control fixtures, flanges,
gaskets, connection elements, calibrated pipe pieces for expansion measurements, silencers for blow-off lines, lines and bypasses for start-up lines
etc.
Insulation





2.2.5

Heat conservation
Personnel protection

For the prevention or the formation of condensation at piping, valves etc.,
with surface temperature less than dew-point of ambient air
Noise insulation to the extent necessary

Vessels
Cold condensate tank
2

(two) cold condensate tanks, complete.
Atmospheric flash tank
2 (two) atmospheric flash tanks, complete
Drain condensate tank
2
(two)
drain
condensate
tanks,
complete,
including
required
drain
condensate pumps Tank, vessels where these are not already included in
the other sections of the specifications.

2.3 Special Technical Requirements
2.3.1

General
The requirements specified in no under section 'General Technical Requirements' are to apply and, where applicable, further regulations from the
other sections of this specification.
The turbine generators and the respective associated equipment are to be
able to be operated without any restriction and any limitation in time at each
load between no-load and maximum load.
Grey cast iron will not be accepted in general. If there should be grey cast
iron contained in a series-manufactured small part which is under consideration,
the
express
approval
of
the
Owner/Owner's
Representative's
Representative is necessary.
Stub pipes on the casings and larger constructional parts must have a
minimum wall thickness of 5 mm; the minimum nominal bore is 20 mm. If
flanges are provided, these are to be at least of nominal pressure 25 bar.
The control valves are to be operated in each case with auxiliary energy.
Direct acting control valves will be accepted only for gland steam controller.

2.3.2

Steam

turbine
Casing
The steam turbine is to be designed to ensure a very good and rapid adaption of the turbine to alterations in load and alterations in the steam conditions.
In order to be able to check the condition of the turbine blading without
opening the casing, borescope openings are to be provided at suitable
points on the casing.
In order to allow for rapid assembly and dismantling, the turbine casing is to
be split horizontally and supplied with guides to permit safe lifting of the
casing.
The casing and their built-in features is to be supported centrically as far as
possible. The design and surface preparation of the supports are to be such
that thermal expansion is not prevented. Packing plates shall be provided to
enable good alignment to be achieved.
Blading, nozzle segments
Rotor and stator blades, nozzle segments and control parts are to be produced in erosion and corrosion resistant material (stainless steel).

For all rotor blades, only fully machined or pre-forged and mechanically
machined
designs are permissible. For the
first rotor blade stage
only
milled shrouds are permitted (shroud band integral to the blade and formed
by . machining). The low pressure rotor blades are to be provided with additional edge protection, where necessary. The turbine stages operating in
the steam region are to be provided with sufficient water drains.
Rotor
The coupled critical speeds of the turbine
outside the range from 85% to 120% of the
be statically and dynamically balanced in the factory.

and generator rotor must lie
nominal speed. The rotor is to

It must be possible to re-balance the rotors on site without particular difficulty. The fixed parts of the steam turbine plant must be free of any resonance which might disturb the operation .
In the design of the rotor, all notches, sharp inner edges or excessively
small radii are to be avoided so that fatigue failures are excluded. All
internal radii arc to be provided with a high quality surface finish.
Bearings
Basically, the bearings are to be designed as horizontally
ings. The thrust bearings must be capable of taking load
and be self-aligning. They must be axially adjustable.

split plain
from both

bearsides

It must be possible to check the thrust bearing wear during operation.
Earthing brushes are to be provided at the turbine side bearing of the
generator to protect the bearings. Similarly the necessary bearing and pipe
insulation must be provided to give protection against eddy currents. In
order to prevent oil leaks, suitable bearing seals such as oil thrower rings
are to be provided.
It must be possible to dismantle the
turbine casings or dismantling the generator.

bearing

shells

without

removing

the

Gland steam
Gland steam must not be discharged into the turbine hall. The labyrinths
be provided should have spring elements if possible. It must be possible
inspect the outer labyrinth through a removable cover without having
open the turbine.

to
to
to

The gland steam system is to be provided with a gland steam and vapour
condenser and vapour suction fans. The materials to be used for the gland
steam condenser shall be of stainless steel material.

Emergency stop valves, governor valves, reducing valves
Spindles, fittings and control parts are to be manufactured in stainless steel
material. The guide surfaces are to be manufactured in hard wearing materials
or they must be armoured. Spindle leakage losses must be avoided by suitable
seals.
In order to facilitate the safe and reliable shut-down of the machine, the
emergency stop valves and governor valves must be arranged with easy
access as near as possible to the appropriate turbine casings. In so far as
flange connections are provided on the live stearn side, these are to be
executed as high quality designs.

Turning device
Hydraulic or electrically driven turning devices may be employed. The turning
device must disengage automatically as soon as the turbine speed exceeds the
turning speed. Automatic engaging of the turning device must be foreseen
remotely from the central control room and manually from local position. A
manual turning gear provision should be included for the black periods.
If jacking oil pumps are used they are to be interlocked so that turning without
jacking oil supply is precluded. Interconnection between the lubricating oil
supply and turning operation is to be ensured by automatic interlocks.

Couplings
If toothed couplings are employed, these are to be provided with forced oil
lubrication. All parts of toothed couplings are to be fully machined. Coupling
hubs and sleeves are to be individually balanced, statically and dynamically, at
a speed corresponding to the operating speed. For the design the short circuit
shock has to be assumed at least 8 times the nominal torque on the drive
coupling for at least 100 times. If necessary, this value is to be corrected
upwards after the torsional critical speed calculations for the total plant and the
actual generator short circuit torque are known.

Other turbine equipment
The turbine bleeds above I bar are to be provided with bleed steam emergency
shut off or emergency check valves.
2.3.3 Lubricating and control oil system
The lubricating and control oil system serves to supply the lubrication points
and the control equipment of the steam turbine. The oil supply equipment is
to be arranged in a separate oil room.
The temperature rise of the bearing oil in the bearings must not exceed 30
K, and the oil drain temperature of the bearings must not exceed 75 0C.
The oil tank is to be dimensioned so that the content is not changed more
than 10 times per hour.

Oil vapour suction fans and oil separators are to be provided. The possibility
of unacceptable concentration of the oil vapour must not exist at any point of
the oil system.
All oil-carrying parts must be separated from equipment subjected to hot
steam so that premature ageing of the turbine oil and the danger of fire is
excluded. The oil pipes must be run in separate oil ducts away from the
cables.
The oil pipes must be seamless and connections between oil-carrying parts
must be welded or flanged. Flange connections of the oil pipes outside oil
ducts and turbine oil room must be encapsulated. The fastening of the oil
pipes must be such that excessive vibrations are excluded. Oil drain points
are to be equipped with double stop valves. It must be possible to shut off
the control oil circuit separately.
The auxiliary oil pumps should he arranged on the oil tank. The auxiliary oil
pump must be able to start automatically in the case of a drop in oil pressure. If positive displacement pumps are employed, pressure relief valves
must be provided in each case for the full flow quantity. To avoid an
unallowable drop in pressure during switch over of oil pumps, a pressure
accumulator is to be installed in the oil system (if necessary).
The DC emergency oil pump has to be connected electronically in a failsafe
way. It has to be ensured by proper means so that the pump is always
working in emergency cases. Off-command from the central control room
shall only be possible in case of turbine standstill.
The oil coolers are to be provided with a withdraw able tube bundle. If2
coolers are installed; they must be switch able during operation without
interruption of the oil flow and must be easy to clean. The coolers are
connected to the closed circuit of the plant auxiliary cooling water system.
The materials used for the oil coolers shall be equivalent to the materials •
specified for the gland steam condenser.
The oil filters in the lubricating oil main circuit and in the control oil circuit are to
be arranged as duplex filters which can be switchover without interruption.
In addition, an oil separator (preferably of the centrifuge type) with all auxiliary
equipment is to be provided for at least 3% of the circulating oil flow. The
separator shall be capable of being used both in operation and when the
turbine is out of service. Those parts of the oil separator in contact with fluid are
to be manufactured from stainless material. Dirt and all solid particles greater
than 5 microns are to be removed in the oil separator. However, oil additives of
any type should not be removed from the oil. It is necessary that an oil vapour
extraction must be provided for this equipment. The oil separator delivered shall
be of the self-cleaning design.
The different oil systems are to
arrangement and different colouring.

be

made

easily

A suitable sampling device shall be provided for the oil tank.

distinguishable

by

a

clear

The scope of the system should include the lube oil transfer pump and motor,
clean and dirty storage tanks and lube oil conditioning equipment. All piping
from the lube oil storage tanks to the lube oil conditions, to the main turbine
reservoir and the lube oil conditioner to the rooftop vents is included.

2.3.4

Insulation
In order to avoid a possible penetration of oil, insulation with an oil-tight hard
cover is to be provided for the turbine. Damaging heat radiation on to- the
foundations must be avoided.
Asbestos insulating material will not be accepted.
Hot sections which cannot be insulated, such as for example observation
openings, are to be provided with a corresponding contact protection.
All external thermal insulation shall be of the blanket type and be capable of
removal and replacement for overhaul purposes without damage. Thermal
insulation shall be provided, where appropriate, to prevent adjacent concrete
surfaces from reaching excessive temperatures.

2.3.5

Turbine cladding
The turbine cladding is to be designed as a sheet metal cladding with noise
insulation and provided with sufficient corrosion protection. It shall cover the
complete turbine area including the turbine outer bearings. Heat build-up
within the turbine cladding is to be avoided by suitable ventilation.

2.3.6

Downtime ventilation
The maximum relative humidity in the turbines during standstill downtime
periods shall not exceed 40% under all possible ambient conditions and
suitable airdrying plant and connections shall be provided for the ventilation.
The air guidance within the unit to be protected is to be arranged so that all
parts experience a sufficient flow. The ventilation equipment is to be
designed for at least two air changes per hour referred to the volume to be
ventilated.

2.3.7

Fire protection equipment:
The fire protection equipment shall be provided as far as applicable.
The lubrication and control oil areas shall be provided with:

2.3.8



automatic fire detection and alarm system



utilizing flame and heat detectors



automatic fixed fire extinguishing system with alternative manual operation

Condenser

The design of the condenser shall comply with the design data of the
turbine generator. In dimensioning the heat exchange surface it must be
assumed that all the load cases must be met even if 10% of the condenser
tubes are blocked. Under-cooling of the condensate is to be avoided. The
pressure design on the steam side must at least cover the range from full
vacuum to bar gauge and, on the water side, at least 3 bar gauge.
The water side of the condenser is to be divided into two independent
halves. Each half must be so dimensioned that the turbine generator can be
operated with corresponding decreased load while the other half is out of
action. The condenser has to meet the requirements of the main cooling
water system with respect to material. The Contractor must show that
sufficient experience with the chosen material is available; in particular
reference shall be made to the expanding of the tubes into the tube plates
and the welding of the tube plates to the condenser shell.
Dangerous vibrations of the condenser tubes must not occur during operation. Therefore a corresponding number of carbon steel tube support plates
must be employed. If necessary, baffles are to be provided to protect the
tubes. The holes in the tube plates and tube support plates shall be accurately drilled, renamed and chamfered on both sides to facilitate assembly
of the tubes. Sufficient space is to be provided for withdrawal of the
condenser tubes.
Each half of the water chamber shall contain venting and water drain
connections of adequate size. Sufficient and manually actuated venting at the
cooling water side in case of sudden outage of the main cooling water pumps is
to be provided. The water side of the condenser is to be designed so that
satisfactory functioning of the continuous condenser cleaning equipment is
ensured.
The water side of the condenser is to be designed so
functioning of the condenser cleaning practice by chemicals is ensured.

that

satisfactory

The arrangement of the condenser must be such that no unacceptable forces
can be exerted due to thermal expansion, over-pressure or. the filling of the
steam space with water.
In addition, the condenser
during start-up or operation.

must

be

suitable

for

accepting

all

drains

occurring

A suitable number of manholes with internally held covers is to be provided on
the steam and water sides of the condenser having at least a nominal bore of
500 mm. Furthermore, means of observing the vulnerable condenser tube
regions must be provided.
The capacity of the hotwell shall correspond to a condensate flow of at least
2.5 minutes during full load condenser operation. The complete control loop for
controlling the hotwell level including minimum condensate flow and control
valves is part of the condenser. Local pneumatic control devices are not

accepted.
All connections in the vacuum area must be welded.

2.3.9

Continuous condenser cleaning equipment
The condenser shall be equipped with a sponge baIl condenser cleaning
system. This equipment shall be controlled locally. For this purpose a local
control panel and all interconnecting cables for measurements and motors
shall be provided. The local control panel shall contain all necessary control
and switchgear equipment and shall require only one feeder. Potential-free
contracts shall be available for annunciations in the central control room of
any fault in the condenser cleaning part.

2.3.10

Turbine bypass stations
The turbine bypass stations serve to remove surplus steam from the hot
reheat steam line into the condenser in case of start-up/shut-down or
turbine trip as well as HP steam into the cold reheat line. The bypass
stations arc to be provided completely with pressure and injection water
regulation. It must be suitable for automatic operation. The opening of the
by-pass valve is to be interlocked with pressure checks for injection water
pressure and condenser pressure. The pressure setting must be adjustable.
Turbine bypass operation must be possible without time restrictions. This
system should be sized for approximately sixty (60) percent, of the normal
main steam flow.

2.3.11

Evacuation units
Either steam ejectors or waterring pumps may be employed for
maintaining the vacuum in the condenser. They shall be designed
sufficiently large to maintain the vacuum in the condenser even with small
leaks. The start-up vacuum shall be provided by means of a start up
evacuation unit.

2.3.12

Main condensate pumps
The rate of delivery of the main condensate pumps should be at least
according to the quantities in the worst combination of their occurrence.
The delivery head of the main condensate pumps is to be stated by the
Contractor.
Casings and rotors are to be provided with wear rings in order to permit
easy replacement of the parts subject to wear. Condensate from the discharge pipe is to be used as sealing water as far as required .
The pump motors are to be so designed that even with 25% overload the
pumps will not be switched off. Pumps and driving motors are to be supplied on a common base plate.

The installation height of the pumps and the NPSH value of the pumps are
to be matched to one another so that there will be sufficient suction head
even under the most extreme operating conditions.

2.3.13 Generator and generator main connections
Generator
The generator shall operate satisfactorily as a single unit, in parallel with the
other unit and with the grid system under all normal working conditions and
shall be designed for continuous operation.
The connections of the generator and the auxiliaries are indicated in the
tender drawing "General Single Line Diagram".
The generator shall be of the 2 pole cylindrical rotor type.
Generator stator
The casing of the stator should be of fabricated steel construction.
The stator core has to be made of high permeability low loss stampings,
tightly clamped together to reduce noise and vibration to a- minimum.
Attention will be given to prevent excessive vibration at twice rated frequency being transmitted to the generator foundations, pipes or associated
equipment.
The stator winding is to be star connected and should be so designed such
that the replacement of a damaged portion is a relatively simple matter. The
winding shall be effectively braced and blocked to withstand without being
permanently disturbed, the forces set up by single phase or three-phase
short circuits at the terminals. The general construction of the stator and the
bracing of the winding overhang shall be such as to provide adequate
cooling surfaces and the avoidance of hot spots.
Suitable anti-condensation heaters has to be provided which will be energised automatically when the generator is shut down.
Generator rotor
The cylindrical rotor body shall be of forged steel, comprising one solid
forging. After rough machining the forging shall be subjected to 100%
ultrasonic examination. Damper windings or damper wedges have to be
fitted as necessary to prevent cyclic irregularities and as a precaution
against local overheating of the rotor surface.
The design of the rotor cooling system should ensure that no hot spots
develop. The packing blocks used in the rotor winding has to be of
approved materials and suitable for the high temperatures and mechanical
forces which exist in the rotor.

Particular attention will be given to the insulating and securing of the rotor
winding and its connections to avoid vibration and the possible failure of
either conductors or its insulation. Rotor retaining rings will be thoroughly
tested
before
application
to
the
generator
rotor
(ultrasonic
penetrate
inspection).
An earthing brush has to be fitted at a suitable position on the shaft, which
is free from contamination by oil etc. Brush changing should be possible
safely
and
easily
while
the
generator
is
operating.
Where
necessary
suitable precautions shall be taken against harmful flow of shaft currents by
the provision of insulating bearings. Insulation provided for this purpose has
to'" be designed to withstand a test voltage of 2 kV AC.
Generator bearings
The bearings shall be of the metal sleeve type and designed so as to be
readily accessible and replaceable without the removal of the rotor.
All bearing oil wells shall be provided with
ready means of checking oil flow, filling and draining.

visual

oil

level

Thermometer pockets must be provided on each sleeve bearing
type thermometer with adjustable alarm contacts to provide.
excessive oil temperature ..

indicators

and

with a dial
warning of

Bearings dependent on lubricating oil has to be provided with a complete
and approved lubricating oil system capable of maintaining the continuous
operation of all parts of the machine, without undue heating, at all loads,
together with the necessary equipment to provide suitable lubrication during
normal start-up and shut-down, emergency shut-down, barring and all other
conditions. The system for the generator will be part of that for the prime
mover and automatically maintained.
Generator excitation system
Provision shall be made for
operation of the main generator.

testing

the

excitation

equipment

without

the

A brush less rotating diode type (RE) of excitation system or a terminal-fed
static excitation system (SE) may be supplied, provided the Bidder/Contractor can prove this is his standard system and there is proven and extensive
experience on installations in similar locations to the Site.
A block diagram of the complete excitation system has to
together with the constants of the transfer functions for the
stabilizing circuits. The time constant of the exciter shall also be included.
The over-current capability for the generator shall be 150%, 30 s.
The nominal exciter response has to be not less than 0.5 s' 1.

be supplied
control and

The continuous rated current and voltage of the main exciter has to be not
less than 110% of the generator excitation current and voltage required to
maintain rated output at the terminals of the generator. The ceiling voltage
must not be less than 200% of maximum continuous rating.
Rotating exciters have to be of the enclosed ventilated
be directly driven by the generator.

type. IP54. They will

Anti condensation heaters shall be provided in the air circuits of the exciter.
The leads from the heaters has to be brought out to an isolator located
close to the bed plate with suitable interlocks provided to energise the
heaters with the generator at stand-still.
Ventilating air for rotating AC exciters should be closed
incorporating an air-to-water heat exchanger. and shaft mounted fans.

circuit

cooling.

Generator exciter
• Rectifiers for RE system
The rectifier bridge will comprise a simple three phase full wave configuration. Each bridge arm shall consist of a number of diodes in parallel per arm
with suitable protection incorporated.
Particular attention should be paid to the full load and
ments of the generator in addition to the protection of the diodes.

field

forcing

require-

The repetitive peak reverse voltage rating of the diodes in each arm of the
rectifier
bridge
shall
be
greater
than
the
maximum
reverse
voltage
appearing across an individual diode by a factor of at least 2.0. The
maximum
reverse
voltage
appearing
across
the
rectifier
bridge
will
be
determined from a calculation of the induced voltage following a faulty
synchronization.
Suitable surge suppression equipment shall be provided across the
bridge if necessary to afford overall protection of the rectifier
excessive over voltages

rectifier
against

In order to protect the diodes when connected in parallel. either each diode
should be protected by an H.R.C. fuse together with individual R-C circuit
suppression and diode failure indication or. if the Bidder/Contractor can
demonstrate that individual fuse protection is not required. consideration •
will be given to incorporating such fuse protection in the AC leads from the
exciter. Preference will be given to those schemes uti!ising diodes of
sufficiently high peak reverse voltage capability such that the requirement
for individual diode R-C circuit suppression may be eliminated.

The diodes in the rectifier bridge has to be continuously rated such that
generator full load. field forcing, fault conditions and a reserve capability of
at least 20% can be carried with one failed device per bridge section. A
diode failure detection device is required to monitor all diodes forming therectifier assembly.
The
Bidder/Contractor
should
describe
the
method
used
to detect and report such failures and the resultant action of the excitation
system.
Rectifiers for SE system
The thyristor converter shall incorporate a number of three phase full wave ,
bridges, and has to be arranged so that a minimum of20% reserve capacity
is incorporated. The converter should be of modular construction so that a
minimum
of
one
bridge
may
be
removed
for
maintenance
(shut-down
required), which still allow full load excitation and unit operation without any
restrictions.
In the event that the converter derives its AC power requirements from the
main
generator
terminals,
the
excitation
supply
transformer
should
be
capable supplying full field forcing voltage at 80% of rated generator output
voltage. In addition a permanent DC control supply for electronic circuits will
be provided with such a method of converter supply.
The thyristors are to be protected by line or arm H.R.C. fuse as appropriate.
and may operate in connection with suitable crow-bar circuits. Indication of
thyristor failure has to be provided. Provision shall be made in the design of
the converter for the protection of the thyristors against gross over voltages.
The repetitive peak reverse voltage rating of the
the three phase bridges of the converter has
maximum reverse voltage appearing across an
factor of at least 2.0.

thyristors in each arm of
to be greater than the
individual thyristor by a

Suitable surge suppression equipment shall be provided
the converter unit to ensure overall protection of the converter.
Provision has to be
heat sink temperatures.

included

for

The thyristors shall be continuously
forcing and fault conditions can be
section.

the

detection

and

across

the

annunciation

input

of

of

excess

rated such that generator full load, field
carried with one failed device per bridge

Generator voltage regulation
The excitation control equipment shall consist of automatic voltage regulator of the static type with single channel together with a manual control
device. The system must be capable of either automatic and manual operation
and
will
incorporate
appropriate
auto/manual
changeover
facilities.
Local and remote set point control shall be provided for both automatic and
manual control.

The system shall include suitable limit control features, fault detection and
protection
features
and
where
appropriate
generator
transformer
overfluxing protection. In the event that dual channel operation is offered,the standby AVR
channel
will
be
continuously
monitored,
and
system
operation
and protection shall be unaffected by transfer of control from one channel to
another.
The thyristor output stage of the excitation control equipment
continuously rated for the excitation demand of the generator at
field forcing under fault conditions and a contingency of 75%.

must be
full load,

Generator automatic voltage regulator (AVR)
The A VR shall be of the continuously acting type with no dead bands
enabling
control
of
the
excitation
over
the
whole
generator
operating
characteristics. The AVR must be capable of maintaining the generator
terminal voltage within ± 0.5% of the set value for any voltage deviation
over the whole load range of the generator.
The voltage response characteristic should be given by
AVR damping control at normal, maximum and minimum settings.

the

Contractor

The AVR must be equipped with an active power dependent
stabilization circuit (Power System Stabilizer) for damping rotor oscillations.

for

voltage

Generator excitation limiter
A minimum excitation limit device has to incorporated to prevent the AVR
reducing the generator excitation below a value which might endanger
power system stability limits. The limit unit shall be arranged to provide an
alarm and interlock in the event of extreme low excitation when operating
under either automatic or manual excitation control.
The characteristic of the var-Iimiter must be adjustable and facilities should
be provided so that the var-Iimiter operating characteristic can be adjusted
to any setting within the specified range.
Over-excitation protection must be incorporated to ensure that if excessive
excitation is sustained beyond an adjustable present current/time limit, the
A VR is either tripped or the excitation is automatically ramped down. The
current/time setting must be such that no damage will be caused to any part
of the A VR or to the excitation rectifiers.
The AVR shall in addition include the following protective devices which
trip the AVR to manual control and initiate appropriate alarms and still
the set after a predetermined delay in the range 0-30 min.:


Overvoltage protection



Overcurrent protection



V.T. fuse failure protection



AVR failure protection

will
trip



Overfluxing protection (volts/Hz protection)



A VR power supply failure protection.

Overnuxing protection must be provided and will be part of the excitation
control system and shall be operative during both automatic and manual
modes of excitation control. The protection has to prevent the transformer
magnetic flux from rising to a value at which the voltage/frequency ratio,
pre-set within the range 1.00 to 1.25, would be exceeded.
Generator control
An approved means of manually controlling the excitation
primarily for generator commissioning and maintenance
will be possible from approximately 0 to 110% UN.

must be provided
purposes. Control

Means for both local and remote (from central control room) operation or
the manual control shall be provided with


auto/manual balance indicator (local cubicle and central control room).



changeover switch (local cubicle and central control room).
However, remote
III use.

changeover should be inhibited when the local control is

A follow-up device must be provided to automatically adjust the standby
manual excitation control so that in the event of a changeover from
automatic to manual control here will be a minimum change in lhe level
or excitation.
All automatic limiter shall stop the automatic folIow-up device or the
manual
voltage
controller
from
reducing
the
manual
voltage
regulator
selling below the prescribed are limits of excitation for the generator when
under manual control. The characteristics or the limiter shall have the
same range of adjustment as the var-limiter of the AVR channel, but when
commissioned will be set for less leading conditions than the var-limiter.
Generator droop compensation
Quadrature
droop
compensation
must
be
provided
to
ensure
correct
sharing
reactive
power
in
accordance
with
generator
rating.
The
compensation shall have an adjustable compensation range of ± 10% and
has to be so connected that the compensation can readily be taken out of
service.
Generator exciter field suppression equipment
The exciter field suppression equipment shall be provided and may be
accommodated within the AVR cubicle. The field switches must be capable
of making and breaking the circuits under the most onerous fault
conditions. The switches shall be suitable for local and remote as well as
automatic operation. The generator field switch must also be suitable for
manual operation.

Means has to be provided on the cubicles for indicating
remotely whether the switches are in the 'open' or 'closed' position.

locally

The field suppression resistor shall be
maximum field current as quickly as possible.

to

non-inductive

and

rated

and

suppress

Generator sliprings and commutators
Where slip rings, commutators, and associated brush gear are provided
they must be designed to operate without injurious sparking or excessive
wear and it shall be possible to run for Ht least four months without
replacements of the brushes. The brush gear housing has to be designed to
provide
maxill1
umvisibility
via
inspection
windows.
Guards
of
insulating
material should be mounted between the slip rings and between brush
holders of opposite polarity.
Approved arrangements shall be made for locating and operating
for grinding surfaces. The grinder has to be supplied under this Contract.
Slip rings and commutators should be in a separate cooling
so that dust from brush gear wills not enter the exciter generator windings.

a

medium

grinder

circuit

Generator temperature measurement equipment
Pt 100 temperature detectors and indicators of approved type shall be
provided for measuring the maximum internal temperature of the generator
and the cooling medium temperatures. The positions will be subject to
agreement and provision should be made for the following requirements:


stator windings, between coils in slot









cooled air from coolers (per cooler section)
hot air from generator (per cooler section)
direct cooling water (if applicable)
exciter cooling air inlet
exciter cooling air outlet
bearings (generator and exciter)
spare on terminal board for test purposes
Each indicator must have adjustable settings for
ture alarm which shall be independent of the
lected.

initiating a
temperature

high temperaindication se-

The leads from the temperature detectors have to be brought out to a
terminal box on the generator in a position which is accessible during
normal operation of the set. All temperature detectors shall Rave the same
characteristics. A multi-point temperature indicator with selector has to be
mounted in the central control room.
Generator cooling equipment

The generator cooling system must be complete and include all necessarycoolers, fans,
pumps
and
control
apparatus
as
required
for
safe
and
efficient operation of the plant and has to comply with the requirements of
IEC 34-3.
As cooling systems the following has to be provided:
•Internal closed-cooling cycle with air-to-water coolers
cooler) as preferred solution, cooling classification
IC7A1W7,

(incl. one stand by
of complete generator

or alternatively
•internal
closed-cooling
cycle
with
water
cooling
directly
through
stator
winding and rotor winding together with internal closed-cooling cycle with
air-to-water coolers (incl. one stand by cooler) for the remaining parts,
cooling classification of generator stator and rotor windings IC3(W7)W7
and of remaining parts IC7A1W7.
If H2 cooled Generator is proposed, Contractor has to supply, install 2x 100%
capacity H2 Generator, 02 nos. of H2 compressor (for H2 storage bottles), H2
storage bottles, on line H2 analyzer, H2 dryer, Co2 system etc.
The generator coolers etc. must he sized so, that rated generator output at
class B operation can be mainlained with 10% of the tubes blocked. The
cooler and isolating valves have to be arranged to permit easy isolation and
cleaning of individual sections after shut-down. With one cooler section
withdrawn, the operation of the generator can be continued at rated generator output, utilizing the thermal limits of class F.
The cooler tubes shall be mounted and supported
expansion and vibration. Any necessary apparatus
withdraw
the
air coolers or permit repair has to be provided. Water
detectors
must
be provided for all coolers, which will initiate an alarm in
a
leak
occurring.
CO2 equipment

to allow for the effects or
required to
9 positions

leak

1 position
1 position

the event of

18 positions
1 position

position
positions

each

2 positions.

CO2 systems have to be provided, including the
individual
CO2
bottle
storage close to each generator, the bulk CO 2 storage
plant
(outside
machine house) and all required equipment for satisfactory operation, such
as piping to the generator housing and to the bulk CO 2 storage plant,
:valves, vaporizer, fittings, hangers, supports, control and supervision.
Generator main connections (GMC)
The GMC's are to be designed ns self-cooled isolated-phase busduct system
protected against contact and designed for indoor and outdoor installation. The
complete GMC system must be provided with the necessary current and
voltage transformers, earth switches, star point connections for the generator,
overvoltage capacitors. isolating links li)r the unit auxiliary transformer and all

required fittings and internments.

The basic circuit of the GMC's and the instrument transformers and other
equipment is shown in Annex B8-2. All the necessary controls, regulating,
measuring and monitoring instruments including meters are to be provided
locally and/or in the central control room.
The GMC's are to be designed for the thermal and dynamic maximum
short-circuit currents occurring. All supporting and other constructions both
inside and outside the GMC, where not made of aluminum. must be made
in a hot-dip galvanized design. In the GMC-branch busduct to the unit
auxiliary transformer isolating links are to be provided in the single-phase
busbars. Anti condensation heaters are to be provided in each separate
GMC section.
GMC generator star point
The star point is to be made directly behind the generator bushing type
current transformers provided for this purpose. This high voltage section is
to be enclosed by a cubicle unit with solid metal walls. The earthing transformers as required by the generator stator protection system may be
arranged also in this cubicle if applicable.
GMC connection cubicles
Along the indoor run of the GMC's, all
voltage transformers, overvoltage capacitors,
be housed in steel sheet cubicles.

further auxiliary items such
earthing isolators, etc. are

as
to

GMC current and voltage transformers
All current transformers (CT) and voltage transformers
provided in accordance with lEC 144 respectively lEC 186.

(VT)

are

to

be

A tripping time of live seconds is to be taken as a basis for the thermal
stability of the transformers in the GMC's. The current transformers will be
or the toroidal type, cast resin insulated.
GMC transformer and cubicle connections
The generator step-up transformers and unit auxiliary transformer are to be
connected in a way that, in the event of any short-circuit forces, no harmful
deformations can occur.
The distances between the individual transformer bushings and therefore
the spacing and height of the main generator busducts arc to be selected
so that both repair and maintenance work can be carried out without any
difficulty.
In the case of three-phase terminal cubicles arc-proof
provided between the phases for both the generator
connection.

partitions are to be
and the transformer

GMC earthing switches
Motor-driven earthing switches of short-circuit-proof design arc to be used. The
necessary interlocks with the 230kV circuit breaker, etc. arc to be provided.

GMC protective capacitor
To reduce
the
overvaulting
installed
and
connected
to
generator step-up transformer.

stress,
three
protective
capacitors
the
generator
main
connection

must
near

he
the

Generator unit protection, synchronizing, measuring
Unit protection system
For the generator and unit protection system, digital protection relay types
has to be used. The individual relays or relay groups are to be installed in
the plug-in principle in standardized steel sheet cubicles. The basic circuit
will be as shown in Annex B8-2.
The protective relays are to be divided into two groups with the relays
group 2, for example, representing the back-up protection of the relays
group 1 and vice versa.

in
in

The subdivision of the protective relays into groups is to be associated with
fully
automatic
self-check
facilities
(watch
dog)
enabling
the
protective
relays self-test during operation without imposing any operating restrictions.
On request the test values will be printed, values outside the allowable
limits will be marked in the print and an alarm will be actuated.
The
Contractor
must
coordinate
the
with the protection system of the 230k
system of the grid.

aforementioned
protection
equipment
V switchgear and with the protection

Synchronizing
The general synchronizing point will be the 230kV
type electronic parallel-switching apparatus must be provided.

circuit

breaker.

A

plugin

In general, the 230kV circuit breaker will be synchronized by means of the
automatic
program,
but
all
required
equipment
for
conventional
manual
synchronization from the local generator control panels must he provided.
for this purpose, the parallel-switching measuring instruments such as twin
voltmeters, synchroscope and twin frequency meters will be integrated with
pushbuttons for speed regulation and voltage adjustment in the local generator control panels.
In case of manual synchronizing, this will only be
ON command is released by a separate synchro-check relay.

possible

when

switching-

Application of the appropriate voltage transformer outputs is to be effected
simultaneously with the choice of synchronizing point (synchronizing
selector) from the central control room.
Measuring
Electrical measuring and metering equipment must be provided locally and
in the central control room minimum as per the basic circuit shown in Annex
B8-2.

2.3.14 Control and monitoring equipment
Refer also
sections B9.

to

the

general

requirements

on

control

and

monitoring

in

The regulation equipment supplied must successfully control rapid changes
in load. Operation in the speed control mode shall also be possible.
The protection system supplied has to protect the turbine generator plant in
every phase of operation from overload and damage. It must be continually
ready for operation and capable of being checked even during operation
and must not be capable of being switched off even accidentally.
The control, regulation and supervision of the turbine generator has to be
complete and safe in every respect. Where required, 2-channels, 2 out of 3
logic or self-monitored systems arc to be provided.
An electro-hydraulic turbine governor system is to be employed, preferably
with the hydraulic part capable by itself of providing safe operation of the
turbine. The electro hydraulic governor shall embody the following functions:
Governor equipment
The description below contains the regulation tasks and a framework proposal for the solution of these tasks.
The Contractor is required to supply the range of equipment which makes
possible the safe fulfillment of the tasks (\s outlined and the maintenance of
the necessary regulation accuracy. In addition, the regulation circuits must
guarantee stable turboset operation at all load points.
Local instrumentation shall be grouped according to process sub-systems,
e.g. all instruments of control oil pressures and temperatures at a common
place.


Speed control



Inlet pressure control/limiting
and shall fulfill at least the requirements described below:



The turbine shall be capable of being run up from stationary to rated

speed under speed control with a governing accuracy of 1 % or better.
The system must also provide for proper management of automatic synchronizing.
• The speed overshoot caused by a full load shedding has to be less or
equal to 8% referring to nominal speed. The same is required by only
action of the mechanical/hydraulic governor.


A facility for limiting the rate of speed variation shall be provided.
• For the speed a set point adjustment facility
with limiting action on the jump and rate
allowances, shall be provided .

with presettable slope, and
limiter corresponding to the

The electro hydraulic turbine governor must be suitable for co-operating
with a functional group control system, with the jump and rate limiter
described
below
and
with
a
superimposed
distributed
control
system
(DCS).
All
governor
system
status
and
fault
conditions
are
to
be
signaled
individually in the control cubicle. In the event of a fault affecting the electro
hydraulic
governor,
the
mechanical/hydraulic
governor
shall
automatically
take over at least the functions of speed governing and inlet pressure
limiting.
Jump and rate limiter system
As a supplementary feature for the turbine governing system, a jump and
rate limiter system shall be supplied. This shall permit rapid load following
by the turbine and fast load-changing consistent with permitted levels of
material stressing and taking into account the thermodynamic response of
cylinder and shaft. This involves monitoring and evaluation of temperature
deterrence's at representative critical points. The critical points are to be
selected by the supplier in the light on the machine design (e.g. monitoring
of emergency stop valve, high-pressure cylinder and high-pressure shaft).
At least two measuring points are to be monitored accordingly.
The computed allowances are to be made available to the two set point
adjustment devices of the turbine governor for limiting purposes, and fed to
information displays and to the DCS in the central control room. On
attainment of a temperature or stress limit appropriate alarm signals arc to
he initiated.
The
jump
and
rate
limiter
shall
be
designed
to
be
Equipment faults must not lend to unacceptable limitations on operation.

self-monitoring.

Protection equipment
The protection interlock chain "Turbine protection" is to .be executed in
particularly safe and high quality technology and is to he introduced into the
control ns interlock criterion so that the turbine is protected from overload
and damage throughout the complete operating range. The following

protection criteria must be present as a minimum:


Steam inlet temperature and pressure greater than max.


Turbine speed greater than maximum [at least two (2) independent speed
checks for 110/112% with the possibility of testing during continuous
operation]



Bearing metal temperatures (thrust and journal) greater than maximum



Shaft position not correct



Bearing housing and/or rotor vibrations greater than maximum



Wall temperature difference of turbine casings greater than maximum



Control oil pressure lower than minimumj



Lubricating oil pressure lower than minimum



Relative extension greater than maximum



Level in lube oil tank lower than minimum



Generator protection operated



Fire-protection system operated



Unit trip operated



Local turbine trip operated



Condensate level in the condenser



Remote trip from the central control room
It is also necessary to guarantee that the operating personnel will he made
aware of danger by alarms before the operation of the protective mechaI11sms.
The turbine generator plant must be protected
preventive protective interlocks (passive protection).

from faulty operation

by

All the mechanical-hydraulic and electrical protective circuits 011 the turbine
must be so constructed (for example using 2-channel, 2 from 3 selection,
self-monitored principles) that faults in one protective interlock cause no
erroneous release, on the one hand. but do not prevent the initiation or
rapid shut down in actual cases of danger, on the other. The protective
circuits must be supervised by checking the equipment initiated from the
central control room and it must be possible at any time to inspect the
functional correctness of the protection without causing a trip of the turbine.
The protection signals must operate on all turbine emergency stop valves
and, where applicable, on the bleed emergency shut-off valves.

2.3.15 Feedwater pumps
The boiler feed water pumping sets shall be identical in designs and all
replacement parts will he interchangeable.
Only first class approved makes of best quality will be accepted.

33
7

Special emphasis is placed on a high resistance to corrosion of the
equipment. The feedwater pumps with all parts coming into contact with the
feedwater are to be constructed in chromium steel containing at least 13%
chromium. The materials must satisfy without restriction the requirements of
erosion
and
corrosion
resistance
resulting
from
operation
with
dematerialized water and water conditioned with volatile alkalizing agents
having a PH value equal to or greater than 7.0. Protective sleeves on the
shafts arc to be hard chromium plated, cooling sections and bearing
mountings of cast steel.
A reverse rotation locking devise shall be provided for each pumping unit.
The pumps must have generously dimensioned plain bearings (only for
booster pumps ball bearings can be offered as an alternative) and forced
feed oil lubrication. The total axial thrust of the pump shall be neutralized by
a hydraulic balancing device. A thrust bearing shall be provided, which is so
dimensioned that even in the event of short-duration cavitations no damage
to the pump will occur. The hearing metal shall have emergency running
proprieties.
The bearings must be designed
impeller due to thermal expansion.

to

accommodate

displacement

of

the

pump

The shaft seals shall be of the soft-packed stuffing box type in the case of •
booster pump and mechanical seals for main feedwater pumps. The stuffing
box and corresponding gland cover shall be cooled; the seal chamber nt
mechanical seals shall be cooled as well.
Removable wearing
the running joints.

rings

shall

be

installed

on

the

casing

and

All rotating parts shall be statically and dynamically balanced.
shall be carefully machined and polished and where it is
machine, a smooth surface shall be obtained by work.
II must be possible to start the pumps
up. Automatic changeover to the load
possible without delay.

safely from cold
point previously

impeller

at

Each impeller
impossible to

with prior warming
in use must he

The minimum-flow devices arc to he automatically actuated. They shall include
a hand start bypass. The minimum flow lines and balancing lines are to be run
separately for each pump to feedwater lank
Strainers should be included in the suction lines to protect
damage under all operating conditions. The strainer mesh
exceed 0.4 mm. The strainer and strainer body must
th:.1 lthe full area of the strainer is utilized. The free area of
he
at
least
equivalent
to
5
times
the
cross-section
corresponding suction pipe.

the pumps from
size should not
be matched so
the strainer must
m-ea
of
the

The rotor design shall be sub critical.

33
8

To combat vibration, the pumps should be mounted on reinforced concrete
foundation slabs supported on spring elements.
The pumps casing shall be properly insulated and sound protected.
The design pressure of the feed pumps shall be at least 1.2 times the pump
zero now pressure at the highest possible pump speed at cold conditions
and under maximum suction pressure conditions.
Oil supply
A closed oil system having separate internal working and lubricating circuits
must be provided for the feedpump and motor bearings.
The lubrication oil system shall also be equipped with an auxiliary lubricating oil pump which starts automatically in the event of a fall in lubricating oil
pressure. An adequate feed of oil shall be ensured under start-up and rundown conditions.
The oil systems are to be equipped with all necessary filters (double filters),
strainers, pipes, valves, etc. necessary for safe operation. Changeover of
the filters during operation must be possible without interruption and they
must be easy to clean.

2.3.16 Feedwater tanks and deaerators
The deaerator connected to the feedwater tank should be of the spray type
using the "Stork" system or of cascade-type with incorporated re-evaporation. In all cases the feed water tanks must have a warming-up steam line
supplied with steam from the auxiliary steam header.
The size of the deaerator must be sufficient for a water flow of at least 1.1
times the maximum boiler feed water flow plus the maximum feedwater
injection quantity.
If the feed water tank pressure falls, a supplementary steam supply is taken
from the cold reheat manifold. The supply from the cold reheat manifold is
also taken during start-up/shut-down operation, in order to maintain the
required minimum feed temperature.
The deaerator spray nozzles and the nozzle strainers shall be or stainless
steel.
The deacration area must be lined with stainless steel. The entire vapour
extraction system must be manufactured from stainless steel.
To allow for possible slopping of the contents of the feed tank, a horizontal
impact force of 10% of the maximul11 vertical load l11 ust be assumed.

33
9

In order to avoid the danger of corrosion, diverter plates should he lilted in
the dead corners of the feed tank to improve circulation. The wall thick-nesses for the
feed
tank
and
deaerator
shall
have
a
corrosion
allowance
of
at least 3 mm. The tank must be suitably stiffened to safely withstand Cull
vacuum.
All valves and fittings directly above the feedwater tank must be accessible
from platforms.

2.3.17

Piping, valves and

accessories
Pipe and valve specification
The pipe systems must conform to the requirements
"(General Technical Requirements", as a minimum requirement.

declined

in

B0

Interconnection work
Piping systems > DN 80 and > 120 0C must be stress analyzed from anchor
point to anchor point, regardless of battery limits or individual contracts.

2.3.18

Feedwater heaters
Installation and removal of the various items of plant must be possible
without difficulty. Special provisions must be made for the withdrawal of the
heater tube bundles.
The wall thickness for shells and ends shall be at least 8 mm. The heat
exchanger tubes shall be scam less with an inside diameter of at least 15
mm.
An adequate number of inspection holes must be provided at particularly
susceptible areas, such as the steam inlet, above the water level regulator,
etc. to allow visual inspection of the internal condition of the 'heat
exchangers.
The stub pipes shal1 he welded wherever possible, both internally and
externally. Stiffeners with inspection holes for stub pipes should be welded
in place where necessary.
LP feed water heaters
Adequate provision shall be made to protect the turbines against the
backflow of water from the LP feedheaters. In the event of increased level
the condensate of LP feedheaters I shall drain to the turbine condenser. If
the water level rises above a certain set point, a level monitor shall close
the shut-off valves in the bleed steam lines to the LP feedheaters.
Similarly, the emergency drain of the LP feedheaters and the steam side
safety) valves shall be suitable for discharging the maximum rate of
condensate flow according to the requirements

34
0

The LP feed heaters shall be of standard horizontal
tubes. A welded-on hotwell shall be provided for
required). The material of the tubes shall be of stainless steel.

tube-plate type with
water level control

U(if

All pipe collections and all connections on the vacuum side shall be welded.
Valves and other fittings exceeding nominal size
continuously or intermittently under vacuum shall
water connections.
Shell and tube bundle
protection at the steam
proper air extraction so
changers.

of
be

25 mm
provided

which are
with seal

shall be equipped with effective baffle plates and
and drains inlet. Particular care shall be taken for
that no air pockets can form inside the heat ex-

HP feedwater preheaters
During
low-load
operation
of
the
turbine,
when
the
pressure
in
HP
feedheater is no longer sufficient to drive the condensate into the feedwater
tank, the drain is led to the condensate drain tank (if necessary via a flash
tank) via a low-load drain control system. The automatic switchover of the
drain from the feed water tank to the storage tank and vice versa should be
done dependent on the pressure difference between HP heater and feed
water tank considering a suitable hysteresis characteristic.
Adequate provision must be made to protect the turbine against the
backflow of water from the HP feedheaters. If the water level rises excessively
the
feedwater
line
must
be
automatically
by-passed
and
simultaneously
the
motorized
shut-off
valves
and
the
emergency
check
valves in the bleed lines upstream the feedheaters are to be closed without
tripping the turbine.
It must be possible to operate the feedwater bypass valves of the HP feedheaters either manually or automatically. Automatic operation should be by
means of separate level monitors in the HP feed heaters. The operation of
the bypass valve shall not initiate turbine trip.
In case of pipe burst in the HP heaters the 2 out of 3 high level trip shall
initiate immediately the isolation of the HP heaters and bypassing the
feedwater.
The safety valve
must be capable
off valves.

to be provided on the shell side
of discharging the max. leak rates

The HP feedheaters
ME stamped heaters.

shall

be

designed

according

of the HP feedheaters
of the emergency shut

to ASME

and

shall

be AS

All
connections
must
be
welded.
The
feedwater
tubes
must
be
manufactured from high-strength steel. Adequate provision must be made in
the design for the possible expansion of the tubes and internals under the

34
1

different temperature conditions. The complete tube bundle must be stressrelieved.
Effective baffle plates and protection must be incorporated in the shell and tube
bundle adjacent to the steam inlet.
2.3.19 Tanks
Drain condensate tank
The drain condensate tank must be dimensioned for the maximum volume
of condensate arising from the atmospheric flash tank and tundish drains.
The inside tank overflow line is to be so dimensioned that the maximum
inflow of condensate can be discharged without the outflow velocity in the
line exceeding 0.8 m/s. The tank is to be of the horizontal cylindrical type
and mounted as low as possible so that an adequate head exists for all
infeeds.
The condensate level in the drain tank shall be automatically maintained
constant by means of control valve on the pressure side of the condensate
drain pumps. A common line for tank overflow and tank draining is taken to
the hot drainage system. The condensate-coming from the flash tank has
to be introduced into the tank below the lowest condensate level by way of
a pipe with nozzles. The pipe is to be fixed inside on the tank bottom and
must have a clear discharge cross section of at least 2.5 time the pipe
cross section.
Atmospheric flash tank
The atmospheric flash tank is a vertical cylindrical tank which must be so
dimensioned that the steam and condensate are properly separated and
can be separately discharged. The condensate will be discharged to the
drain condensate tank, the steam' to the atmosphere. The condensate
fed to the atmospheric drain flash tank can be run through common
collecting pipes with tangential inlet into the atmospheric flash tank.
Only condensate at approximately the same temperature and pressure can be
combined to a common header. the collecting pipes are not to be arranged at
the same height on the tank circumference.
The collecting pipes entering the atmospheric flash tank are to be so
dimensioned that the flash steam forming on inlet to the atmospheric flash
tank does not exceed a velocity of 100 m/s (if necessary, throttle orifices ate
to be provided in the inlet headers). The condensate is to be fed into the
tank above the highest water level and the flash tank outlet is to be provided
with a water trap to prevent steam from blowing through into the drain
condensate tank. Between the highest point on the water trap and the steam
space of the flash tank a vent line is to be provided for preventing complete
emptying of the water space of the flash tank.

34
2

Minimum Requirements

2.3.20 Drain condensate pumps

All parts of the pumps coming in contact with the water arc to be manufactured
in stainless material. Casings and rotors arc to be provided with wear rings in
order to permit easy replacement of the parts subject to wear. Condensate
from the discharge pipe is to be used as scaling water as far as required.
In normal cases one pump will be in operation. The second pumps shall
start automatically if the operating pump trips.
MW

The pump motors arc to be so designed that even with
25% overload the
pumps will not be switched off. Pumps and driving motors arc to be supplied
on a common base plate.
The installation height of the pumps and the NPSH value of the pumps are
to be matched to one another so that there will be sufficient suction head
even under the most extreme operating conditions.

2.4 Technical Schedules

%
%

The following technical schedules comprise part of this
and requirements specified in the respective forms arc
the missing data of forms arc to be completely filled in.
technical schedules arc to be submitted with the Bid.

Hz

specification. The data
to be adhered to and
The
completed

%

B2/FB Performance and Design Data

%

B2/FD Technical Data by Bidder
Section B2: Steam Turbine Plant

%

Performance and Design Criteria

Unit

Turbine
Turbine type
Number of turbine casings
Maximum Continuous Rating at generator terminals at
cooling
water inlet temperature of 35°C (according to mean cold
water temperature of cooling tower)

K

heating stages

bar

Condenser
Cooling
water
temperature
increase
Maximum cooling
water velocity in
condenser tubes
with
10% blocked tubes
Design pressure
Max.
cleanliness
factor referred to
design
cooling
surface

%

Permissible deviations of live steam pressure and live
steam temperature
m

Permissible tolerance of swallowing capacity

#

Frequency
Permissible frequency deviations at Maximum
Continuous Rating
without limitations
maximum 20 minutes duration but not exceeding 2
#
hours per year
maximum 10 minutes duration but not exceeding 1
#
hour per year

Number of pre-

m/s

m/s

Swallowing capacity at 100% live steam pressure

Data

m

Minimum
cooling
water velocity in
condenser tubes

34
3

Minimum tube bore of condenser tubes
Reheat condensing
steam turbine
2
250 + 10%

According to IEC
recommendations
latest edition
104
-0/+3
50

-3 to +3
-4
-5
minimum 6
max. 10
2.2
full vacuum
110
1.5 or according to

requirement of
sponge ball
cleaning equipment
17

34
4

B2/FB-1

34
5

34
6

BPDB, Barapukuria 250 MW Power Plant

Minimum Requirements

Section 82: Steam Turbine Plant
Performance and Design Criteria
Generator

Rated voltage at generator terminals

Unit

Data

kV
Select between
(11 - 15.75) ± 5%).
50

Rated frequency

Hz

Rated power factor (lagging)

cos phi
cos
phi .
%

0.80

Rated short-circuit ratio kc (without minus tolerance)

-

0.50

Insulation class for generator and exciter

-

F

Permissible operation at MCR according to insulation class

-

B

Rated system voltage

kV

12 - 17.5

Operating voltage

kV

Rated frequency

Hz

Select between1115.75
50

Impulse withstand voltage (to earth)

kV(peak)

75 - 95

Power frequency withstand voltage

kV

50

Type of ducts

-

Secondary current of current transformer

A

Single-phase.
self-ventilated
1

Rated power factor (leading)
Unsaturated subtransient reactance x"d (without minus
tolerance and at rated generator output)

0.92
17

1) Minimum ± 5% voltage variation range. The
Bidder/Contractor may prove. if higher values are appropriate.

Generator main connections (GMC)

Class of current transformer measuring core

0.5M5

Class of current transformer protection core

-

5P20

Secondary voltage of voltage transformer

V

110/ V3,110/3

Class of voltage transformer

-

0.5/0.2

Rated voltage

kV

12 - 17.5

Impulse withstand voltage 1.2/50~s (across open contacts)

kV(peak)

75.-95

Power frequency withstand voltage. 1 min (across open
contacts)

kV

Earthing switch

00

CO

00

CM

B2/FB-2

34
7

BPDB, Barapukuria 250 MW Power Plant

Minimum Requirements

Section B2: Steam Turbine Plant
Performance and Design Criteria

Unit

Data

Combined deaerator/feedwater tank
Mode of operation of
deaerator

°C' Max.
turbine low load
temperature

Design pressure

Design temperature
LP feedheaters
Design pressure of LP
feedheaters (steam
side)

Design temperature of
LP feedheater (steam
side)
Variable
pressure with
fixed minimum
pressure
120% of
respective
maximum
turbine bleed
pressure and
full
vacuum
HP feedheaters
Design pressure of
HP feedhealers
(sleam side)
Design temperature

120%
of
respe
ctive
maxi
mum
turbin
e
bleed
press
ure
and
full
vacuu
m
Maxi
mum
turbin
e noload
tempe
rature
plus
20 K,
but at
least
200
°C
of HP
feed
heater
s
(steam
side)

348

BPDB, Barapukuria 250 MW Power Plant
Design pressure of
HP feedhealer (water
side)
120% of
maximum
operating
pressure
Maximum operating
temperature plus 20
K

feedwat
er
pumps
at
minimu
m flow
and
cold
conditio
ns

120% of maximum
delivery head of the
Drain condensate pumps
No. of pumps

2 x 100%

B2/FB-3

349

Bidder/Contractor
Section B2: Steam
Turbine Plant
Technical Data by
Bidder

Data
Unit

Steam turbine generator
Total number of steam

MW

turbine generators

bar

Maximum Continuous

°C

Rating of turbine

°C

generator

kg Is

Steam pressure at HP-

kg/s

turbine inlet at MCR
Steam temperature at
HP-turbine inlet at MCR

bar

Steam temperature at

%

IP-turbine inlet at MCR
live steam flow at MCR
of turbine generator
No-load steam
consumption
Number of feedwater
preheating stages
Final feedwater
temperature at MCR
Exhaust pressure at
MCR
Exhaust moisture
Coupled critical speeds
up to 150% of nominal
speed

Steam Turbine
Manufacturer
Type

Sectional drawing No.

Casings
Number of casings
Casing design HP
Casing design IP
Casing design LP

Rotors
Number of turbine
shafts
Distance between
bearing centres HP/IP
shaft
LP shaft

B2/FD-1

rpm

mm
mm

Bidder/Contractor
Section B2: Steam
Turbine Plant
Technical Data b y
Bidder

Blading
HP regulating stage:
Type
of
wheel
Mean
blading
diamet
er

Pressure in the

regulating wheel

chamber at MeR

HP/IP blading:
Type of H.P./I.P.
blading
(impulse/reaction)
Number of stages
Length of blades last
row
Mean blading
diameter last row

LP blading:
Type of LP blading
(impulse/reaction)
Number of stages
Length of blades last
row
Mean blading diameter
last row
Exhaust area of last row
(axially)

Data
Unit

Materials
HP/IP outer casing
HP/IP inner casing
HP/IP blade carriers
LP outer casing
LP inner casing

mm

LP blade carriers

bar

HP/IP rotor
LP rotor
HPIIP nozzles
HP/IP rotor blades
LP nozzles
LP rotor blades

mm

Casing of emergency

mm

stop valves
(HP-steam; reheatsteam)
Casing of HP-steam

mm

governor valves

mm
m

Casing of reheat
steam governor
valves
Casing of LP-steam
governor valves
B2/FD-2

BPDB, Barapukuria 250 MW Power Plant
Section B2: Steam Turbine Plant
Technical Data by Bidder
Emergency stop valves

Bidder/Contractor
Unit

Number of valves
•HP-steam
•reheat-steam
Turbine speeds
Rated
rpm
Overs peed trip - electrical
- mechanical

rpm
rpm

Data

HP-steam governor valve
Number of valves
Size

mm

Type
Actuator
Reheat-steam governor valve
Number of valves
Size

mm

Type
Actuator
Bleed steam emergency shut-off valves Type
Manufacturer
Type
Bearings
Number of journal/thrust
bearings Type: Journal
Thrust
Maximum oil outlet temperature

0

C

BPDB, Barapukuria 250 MW Power Plant
Section B2: Steam Turbine Plant
Technical Data by Bidder
Dimensions

Bidder/Contractor
Unit

Total length of turbine generator
Length of foundation

m

BPDB,
Barapukuria 250 MW Power Plant
Width
of foundation

m

Section
B2: Steam Turbine Plant
Height
of foundation

m

Technical Data by Bidder
Weights

Unit

Data

m

Gland part
steam
condenser
Heaviest
to be
handled by crane

Bidder/Contractor

-

Number of condensers
Weight of heaviest part to be handled by crane
Materials:
Weight of complete turbine generator
Tubes

-

Shell and loading time to MCR
Starting

-

t
-

t

• Cold
start
from ambient temperature
Gland
exhauster
• warming-up
time
Number
of exhausters

min.

Type • starting time up to nominal speed

min.

Rating• loading time up to full load
• Warm start after 8 hours
Oil Supply
• warming-up time
Tank capacity
• starting
time up to(per
nominal
Number
of recirculation
hour) speed
• loading time up to full load
lubrication oil system pressure
• Hot start after 2 hours

Main oil pump

• warming-up time
Type
starting
Drivetime up to nominal speed
loading time up to full load
Speed
Turning device
Material of pump casing
Method of operation

Auxiliary oil pump

min.kW

min. m3
min. I/h
min.
bar(g)
min.
-

min.
min.

rpm

-

Turbine rotor speed
Number/capacity of pumps
Drive

rpm
-/%

Type
Rating
Rating
B2/FD-4

kW
kW

Speed

rpm

Material of pump casing

-

-

Emergency oil pump
Number of pumps

-

Type

-

B2/FD-5

Data

Bidder/Contractor
BPDB, Barapukurla Power Plant

Bidder/Contractor

Section B2: Steam Turbine Plant
Technical Data by Bidder

Unit

Rating
Speed
Material of pump casing

kW

rpm
-

H.P. jacking oil pump
Number of pumps

-

Type

-

Rating
Speed
Material of pump casing

kW

rpm
-

Oil vapour extraction
Number of extraction fans

-

Type

-

Rating

kW

Oil cooler
Number of coolers

-

Capacity per cooler

%

Erection (horiz.lvert.)

-

Max. oil outlet temperature

°C

Cooler length
Materials:

mm

Tubes

-

Shell

-

Oil separator
Manufacturer

-

Type

-

Flow rate per separator of lubrication oil flow

%

Heat rating

kW

Rating of drive

kW

Lubrication oil filter
B2/FD-6

Data

Section B2: Steam Turbine Plant

Technical Data by Bidder

Unit

Data

Type

-

Flow rate per filter

%

Grade of filtration

^m

Control oil system

System pressure

bar(g)

Control oil pump (where applicable)

Number of pumps

-

Capacity per pump

%

Type

-

Rating

kW

Speed

rpm

Material of pump casing

-

Control oil filter

Type

-

Flow rate per filler

%

Grade of filtration

^m

Condenser

Total number of condensers

-

Manufacturer

-

Type

-

Arrangement

-

Condensing Operation at MCR:

Steam flow

kg/s

Cooling water flow

m/h

Cooling water temperature rise

K

Cooling water pressure loss

bar

kJ/m2sK

Heat transfer coefficient
Fouling factor (which is considered in the cooling
surface)
Cooling surface (outside diameter)

%
m2

Number of flow passes

-

Bidder/Contractor
BPDB, Barapukuria 250 MW Power Plant
B2: Steam
Turbine Plant
Section B2:Section
Steam Turbine
Plant
Technical Data by Bidder
Technical Data by Bidder
Type or name of system
Diameter of tubes (bore)

mm

Wall thickness of tubes

mm

length between tube plates

mm

Bidder/Contractor
Unit

Unit
Data

Principle of monitoring (e.g. 1 out of 2, 2 out of 3. 2 out of 2
Number of tube
plates etc.) to be entered for:
with support
self monitoring
Number and sizeSpeed.
of cooling
-/mm
highwater connections
Materials:
Condenser pressure, high
Tubes
Temperature of exhaust steam or bypass steam, high
Tube plates

-

Relative expansion, high

-

-

Water boxes Shaft displacement. high

-

-

-

-

Shell

- lining of water boxes
Difference temperature of casing (diametrical
Hotwell capacityclearance), high
Vibration. high
Main condensateBearing
pumps metal temperature. high
Number/capacity of pumps
Lube oil pressure. low
Manufacturer
Fire protection
Type
Generator protection
Nominal capacity
Lube oil tank level. low
Delivery head

Vibration Measurement

minutes
-/%
-

-

m3/h

-

m

Motor rating
Closed valve head
Manufacturer

kW
m

-

Designation of system
Speed
Type of bearings
Type or name of system

rpm

-

-

-

Material of pump
casing/shaft/impeller
Total
number of shaft vibration sensors
Control and monitoring
equipment
Total number
of bearing vibration sensors

-

-

Downtime ventilation plant

Electro-hydr. governor:

Manufacturer Manufacturer

-

-

Designation ofMaximum
system air humidity downstream the turbine

-

%

Type or name of system

-

Number of sensors in total

-

Turbine protection system
Manufacturer

-

Designation of system

-

B2/FD-8

Data

(ref. to ambient temperature)
Method of operation

-

B2/FD-9

BPDB, Barapukuria 250 MW Power Plant

Bidder/Contractor

Section B2: Steam Turbine Plant
Technical Data by Bidder

Unit

Generator cooler (air to closed water system)
Manufacturer
Number of coolers and capacity

-/%

Material of tubes

-

Synchronous generator
Applicable standards
Manufacturer

-

Type

-

Protection class

-

Generator power characteristic curve No .

-

Rated generator output

MVA

Rated power factor lagging

cos phi

Rated power factor leading
Rated active power (at rated gen. output)

cos phi
MW

Rated voltage

kV

Voltage variation range
Rated current (at rated gen. output)

%
A

Rated frequency

Hz

Rated speed

rpm

Direct axis sub-transient reactance saturated x"d
(unsaturated, minimum value)

%

Maximum asym. three-phase short-circuit current

kA (peak)

(at rated gen. output)
Short circuit ratio kc
Interia constant (H) of the stem-turbine-plusgenerator-set (at rated gen. output)
Test voltage of stator winding
Test voltage of rotor winding

-

kWs/ KVA
kV
kV

Data

BPDB, Barapukuria 250 MW Power Plant
Section B2: Steam Turbine Plant
Technical Data by Bidder
Stator
Number of bushings
Type of winding
Insulation Class
Type of insulation
Rotor
Diameter of rotor body
Length between bearing centers
Type of windings
Type of damper winding
Insulation class
Type of insulation
Shut down heating
Rated power
Rated voltage
Excitation System
Type of excitation system (short description)
At no load: Exciter current

Bidder/Contractor
Unit
mm
m
kw
V
A

Exciter voltage
At rated generator output: Exciter current
Exciter voltage
Exciter machine

V
A
V

Manufacturer

-

Type
Power Input
Insulation class
Voltage regulator
Manufacturer

KW
-

Type

-

Voltage regulation range ±

%

Generator dimensions
Total length

m

Total height

m

Total width
Generator weights

m

Stator weight
Rotor weight
Transport weight complete generator

t
t
t

Heaviest part and its weight to be lifted during
maintenance in machine hall

-/t

Data

BPDB, Barapukuria 250 MW Power Plant

Bidder/Contractor

Section B2: Steam Turbine Plant

Unit

Technical Data by Bidder
Synchronizing equipment
Manufacturer
Type
V

Power supply voltage Input
Input range from - to
Frequency range from - to
Adjustable circuit breaker closing time, from to
Max. permissible angle between generator and grid
voltage
Digital generator protection system

Hz

msec

0

El
-

Manufacturer of protection system
Number of cabinets
Auxiliary voltage
Auxiliary voltage range
Protection system testing device

V
±%

Type
Generator main connections
Manufacturer
Type of ducts (short description)
Rated system voltage

kV

Rated frequency

Hz

Rated current

A

Impulse withstand voltage (to earth)

kV(peak)

Power frequency withstand voltage
Max. asymmetric three-phase short-circuit withstand
current
Rated short-time withstand current (3 sec.)

kV
kA(peak)
kA

Data

BPDB, Barapukuria 250 MW Power Plant
Section B2: Steam Turbine Plant

Bidder/Contractor

Technical Data by Bidder

Unit

Data

Current and voltage transformer
Secondary current of current transformers
Accuracy class: measuring
metering

A
-

-

protection
Secondary voltage of voltage transformers
Accuracy class: measuring

V
-

metering
protection
voltage regulation
Earthing switch
Manufacturer
Type of earthing switch
Rated voltage

-

-

kV

Rated frequency

Hz

Rated current

A

Rated short circuit making current

kA(peak)

Rated short time withstand current (3 sec.)

kA

Power frequency withstand voltage

kV .

Rated impulse withstand voltage
Rotor driven earthing switch

kV(peak)
yes/no

Protective capacitors
Type
Number of capacitors

Nos.

Rated voltage

kV

Rated frequency
Rated capacity

Hz
nF

Enclosure of steam turbine generator
Type
Manufacturer
Max. noise pressure level at 1 m distance
BPDB, Barapukuria 250 MW Power Plant
Section B2: Steam Turbine Plant

dB(A)
Bidder/Contractor

Technical Data by Bidder

Unit

Data

HP-steam bypass station
Number

-

Capacity of steam

t/h/%

IP-steam bypass station
Number

-

Capacity of steam

t/h/%

Feedwater pump
Number of pumps /each pump capacity
Manufacturer
Type
Minimum capacity
No. of stages
Type of journal bearings
Method of axial thrust hydraulic compensation
Type of axial bearings
Type of bearing lubrication

-/%
-

m3/h

Oil supply from
Type of glands or seals
Closed valve head
Materials:
Pump casing
Shaft
Impeller
Total power requirement of feed pump sets when the
turbine is running at MCR

-

m
-

kW

VOITH,
Germany

FWP Hydro coupler manufacturer

One pump set in single operation (at max.
speed):
Delivery rate HP/IP

m3/h/m*/h

Delivery head HP/IP

m/m

Net position suction head required
Power requirement of one pump set at motor terminals

m
kW

BPDB, Barapukuria 250 MW Power Plant
Section B2: Steam Turbine Plant

Bidder/Contractor

Technical Data by Bidder

Unit

Pump efficiency at rated capacity

%

Coupling
Type

Data

-

Maximum allowable transmitted load

kw

Booster pump (if applicable)
Number of pumps
Manufacturer

-

Type

-

Type of journal bearings

-

Type of thrust bearings

-

Type of bearing lubrication

-

Oil supply from

-

Type of glands or seals

-

-

Materials:
Pump casing

-

Shaft

-

Impeller

-

One pump in single operation (at max. speed):
Delivery rate

m3/h

Delivery head .

m

Power requirement of one pump set at motor terminals
Coupling

kw

Type
Maximum allowable transmitted load

kw
Bidder/Contractor

BPDB, Barapukuria 250 MW Power Plant
Section B2: Steam Turbine Plant
Technical Data by Bidder

Unit

Feedwater pump motor
Manufacturer

-

Dat

Type

-

Rated power

kW

Rated voltage

kV

Rated speed

rpm

Rated efficiency

%

Rated power factor

-

Starting time

sec.

Protection system

-

Insulation class

-

Type of bearings

-

Type of lubrication

-

Method of cooling the motor

-

(external fan/internal fan/water-cooled)
Deaerator for feedwater system
Manufacturer

-

Type

-

Mode of operation

-

Maximum outnow rate of deaerator

kg/s

Outside diameter (where applicable)

mm

Total length (where applicable)

mm

Materials
Shell (where applicable)

-

Internals

-

BPDB, Barapukuria 250 MW Power Plant
Section B2: Steam Turbine Plant

Bidder/Contract

Technical Data by Bidder
Feedwater tank

Unit

Manufacturer
Nominal capacity

m3

Normal working capacity

m3

Outside diameter

mm

Total length

mm

Materials:
Shell

-

Internals

-

Operating weight

kg

Weight during testing

kg

Water pressure loss at inlet (MCR)

bar

Design temperature deaerator

°C

Design pressure deaerator

bar

High pressure feedheater 1
(Design data at MCR of turbine unit)
Manufacturer

-

-

Type

-

Heat rate

kJ/s
kJ/m2sK

Heat transfer coefficient (outside diameter) condensation/drain

Terminal temperature difference
Steam side

K

Drain side

K
m2

Total heat exchanging surface (outside diameter)
- Shell outside diameter

mm

Total length
Tube outside diameter
Tube wall thickness
Materials:
Tubes
Tube plate
Shell
Weight

mm
mm
mm

-

-

-

-

kg

Data:

BPDB, Barapukuria 250 MW Power Plant
Section B2: Steam Turbine Plant
Technical Data by Bidder

Bidder/Contractor
Unit

High pressure feedheater 2
(Design data at MCR of turbine unit)
Manufacturer
Type
Heat rate
Heat transfer coefficient (outside diameter) condensation/drain

kJ/s
kJ/m2sK

Terminal temperature difference
Steam side

K

Drain side

K

Total heat exchanging surface (outside diameter)

m2

Shell outside diameter

mm

Total length

mm

Tube outside diameter

mm

Tube wall thickness

mm

Materials:
Tubes
Tube plate
Shell
Weight

kg

Low pressure feed heater 4
(Design data at MCR of power unit)

-

Manufacturer

-

Type

-

Heat rate
Heat transfer coefficient (outside diameter) condensation / drain

kJ/s
kJ/m2sK

Terminal temperature difference
Steam side

K

Drain side
Total heat exchanging surface (outside diameter)

K
m2

Shell outside diameter

mm

Total length

mm

Tube outside diameter

mm

Tube wall thickness

mm

Materials:
Tubes

-

Tube plate

-

Shell

-

Data

Weight

kg

BPDB, Barapukuria 250 MW Power Plant

Bidder/ Contractor

Section B2: Steam Turbine Plant
Technical Data by Bidder

Unit

Low pressure feedheater 5
-

(Design data at MCR of power unit)
Manufacturer

-

Type
Heat rate
Heat transfer coefficient (outside diameter) condensation/drain
Terminal temperature difference
Steam side
D rain side
Total heat exchanging surface (outside diameter)

kJ/s
kJ/m2s
K
K
K
m2

Shell outside diameter

mm

Total length

mm

Tube outside diameter

mm

Tube wall thickness

mm

Materials:
Tubes
Tube plate
Shell
Weight

kg

Low pressure feed heater 6
(Design data at MCR of power unit)
Manufacturer

-

Type

-

Heat rate
Heat transfer coefficient (outside diameter) condensation /drain

-

kJ/s
kJ/m2s
K

Terminal temperature difference
Steam side

K

Drain side

K

Total heat exchanging surface (outside diameter)

m2

Shell outside diameter

mm

Total length

mm

Tube outside diameter

mm

Tube wall thickness

mm

Materials:
Tubes

-

Data

Tube plate

-

BPDB, Barapukuria 250 MW Power Plant
Section B2: Steam Turbine Plant
Technical Data by Bidder
Shell
Weight
(Technical data for further feed heaters to be filled
in as required above)
Atmospheric flash tanks
Number of tanks for each boiler and turbine unit

Bidder/Contractor
Unit
kg

-

Cold condensate tank
Number of tanks for each boiler and turbine unit
Net capacity of each tank

m3

Drain condensate tank
Number of tanks for each boiler and turbine unit

-

Installation level

-

Drain condensate pumps
Number of pumps for each drain condensate tank
Capacity of pumps
Manufacturer of pumps
Electrical motor rating

%
kW

Data

Coal Handling System

41
4

B3. Coal Handling System
3.1 General
Existing coal handling system capacity is 300 MT/ hr which is being used
for existing 2 x 125 MW e units.
Existing Coal handling system is receiving coal from the adjacent coal
mine mouth with storage arrangement in the Power Plant coal yard,
transportation and storage in coal bunkers.
The raw coal from the coal mine to the coal storage area is transported
by a single line conveyor belt system. For the transportation of the
crushed coal from the coal storage area up to the coal bunkers of
existing 2 x 125 MW e units, a double line belt conveyor system is being
used.
A 'Coal Processing Plant' to remove iron, hard materials, waste & large
size coal and to control moisture of coal (within the limit of 10%) shall be
provided at the upstream of existing 'Magnetic Separator' with necessary
modification of relevant coal conveyer system.
A single line coal conveyor belt system with two (02) crusher units shall
be provided from the upstream of existing crusher unit to the new coal
yard with necessary modification of relevant coal conveyer system.
A coal conveyor belt system shall be provided in between new coal yard
and old coal yard.
Extension of existing two coal supply belt conveyors shall be provided from
existing unit no. 2 to the new 250 MW unit complete in all respect to feed
coal to the coal bunkers of the 250 MW unit.

3.2 Scope of Supply and Services
3.2.1 Coal handling system
Comprising essentially:
• a 'Coal Processing Plant' at the upstream of existing 'Magnetic
Separator' with necessary modification of relevant coal conveyer
system. Coal Processing Plant shall comprise the following but not
limited to:

Raw coal entry selection belt conveyor

Power double sides plough discharger

Circular vibration screen

Large size waste belt conveyor

Raw coal transfer belt conveyor

Raw coal upper bunker transfer belt conveyor corridor

Hanging ever-magnet iron remover




Dryer
Processed coal weighing belt scale etc.



belt conveyor up to the new coal crusher



two coal crusher complete with feed hopper, electric drive, necessary
supports, explosion and fire protection measure, dust proof housing,
classifier, inertisation devices, screening system



traversing
and
reversible
distribution
belt
conveyors
for
coal
transportation from the crusher to the new coal storage area (open and
covered storage area)



extension of existing two coal supply belt conveyors from existing unit
no. 2 to the new 250 MW unit complete in all respect to feed coal to the
coal bunkers of the 250 MW unit



ventilation and dust collecting equipment for all transfer points



steel structure, stairs, ladders,
supports, discharge hoods



all associated equipment
pulley scrapers, hold barks



auxiliary equipment such as belt weighing scale, coal sampling devices,
all necessary belt safety and protection devices



washdown system to clean the conveyor systems and walkways



weighing facilities (belt scale)



dust extraction and
piping, valves, etc.



passive safety measure to protect the stored crushed coal against selfignition



coal bunker ventilation system



scaling system



PLC safety interlocking system

such

suppression

walkways,
as

belt

system

conveyor

drives,

idlers,

including

bridges,
pulley,

water

3.3 Special Technical Requirements
3.3.1 General
The following factors shall be taken into account on system design and
equipment selection:






safety
reliability
maintainability
minimize indoor and outdoor environmental pollution
standardization of components.
The scope of design and supply of coal handling system include all the

spray

necessary
belt

and

system,

processes and facilities as mentioned.
The length of the coal conveyor system which has to be provided to
transport the coal from the upstream of existing crusher unit to new coal
storage area is approximately 60 meter and the length of the coal
conveyor system from new coal storage area to old coal storage area is 50
meter.

3.3.2 Belt conveyors
Wherever applicable,
conveyor bridges.

the

belt

conveyors

shall

be

lodged

in

closed

An unilateral walkway with open grid flooring shall be provided parallel to
all conveyors. Idler sets shall be provided with labyrinth seals and shall run
true. Bearings shall be of the "maintenance free type", i.e. lubrication shall
be required not more frequent than once per year.
Drive pulleys, tail and take-up pulleys shall be of closed design.
Pedestal bearing shall be provided with labyrinth seals.
Belt scrappers shall be arranged at the discharge pulley and, if
necessary, for tail pulleys.
Material and construction of covering plates between upper and lower
discharge hoods and product guides shall be chosen in view of optimum
sliding behaviour of the product, avoidance of clogging and limitation of
noise. Material shall be stainless steel, reinforced fibre glass or equivalent.
Rubber aprons for guidance shall be provided.
Gears shall be of the slip-on type. Flexible or hydraulic start-up couplings
(depending on size and requirements) shall be used.
In order to reduce the volume of spare parts, the number of different
types for driving units shall be kept to a minimum.
Retention assemblies such as limit switches, true-run switches, belt
monitors, lanyard switches shall form part of the mechanical equipment of
the conveyor plant.
For conveyors of short length, fixed installed tension devices may be used,
while for conveyors of longer length tension carriages or equivalent self
regulating tension devices to be used.
Junction towers shall consist of steel frame work and
Intermediate stairs and steps shall be provided with grid floorings.

outside

cladding.

Above the conveyor heads or take-up stations respectively trolley beams for
a payload of 3 tons shall be provided.

Distribution of coal to the individual coal bunkers shall be done preferably
by a horizontal tripper conveying system. It remains at the latitude of the
Contractor if the tripper conveyors will be provided with carriages,
movable on rails or whether one reversible conveyor will be attributed to
each pair of bunkers. Special care shall be given to the selection of the
sealing system "bunker-tripper conveyor".

3.3.3

Magnetic separator and tramp iron detectors
One inline magnetic separator in conjunction with two tramp iron detectors
shall be installed in the conveyors feeding to the coal crusher. One of the
tramp iron detectors shall be installed upstream of the magnetic separator
and shall activate the magnet, while the other one shall be installed
downstream of the magnetic separator and shall stop the conveyor system
in case that iron is detected.
The magnetic separator shall use an electric magnet and shall be provided
with its own rectifier.
A magnetic separator of the "belt drum" type may be used.
Removal of tramp iron may be made manually by using a trolley. This trolley
shall be supplied with the system.

3.3.4

Weighing facilities (belt scale)
The belt scale of the electronical type shall be integrated in the conveyor
system leading to the boiler.
The scale shall have an accuracy of not less than ± 1%.
Indication
recorded.

3.3.5

of

instantaneous

conveyance,

totalizing

and

tripping

shall

be

Reclaiming system
The raw coal shall be handled by conveyor to the crusher/screen house.
The crushed coal shall be conveyed directly to the boiler coal bunkers. In
the case coal is not needed in the boiler coal bunkers the crushed coal shall
be sent to coal storage areas. The transfer of the crushed coal to the coal
storage area and the distribution shall be done by traversing and reversible
belt conveyors. Crushed coal storage area shall have a capacity of 8 days
plant - MCR requirement considering the worst coal involved. The coal
storage area will be operated only in emergency when coal is not received
from mines.

Suitable traveling type of stacker shall be provided to stack the crushed coal
to a height relevant to the availability of space. Necessary platform with
drainage facility shall be considered. Soil improvement to improve bearing
strength and other requirement shall be considered as required. Reclaim
from both coal storage areas (covered and open storage area) shall bedone by front end
loaders
and
loaded
to
underground
hoppers
for
further
feeding to downstream conveyors of inplant coal handling. Required number
of front end loaders shall also be supplied. Number of front end loaders
shall be adequate to feed the conveyors at 110% MCR of boilers.
The inplant conveyors capacity shall be adequate to fill the boiler bunker in
8 hours operation.
The coal storage areas shall be provided with necessary fire water system
and compacting/dust suppression system.
Covered storage to cater to about 4 days MCR requirement shall be
provided as part of the total coal storage area. The covered storage shall be
constructed with structural steel supports and metallic sheet covering. Size
and arrangement of the covered storage shall be such that it shall not
hamper stacker movement/operation.

3.3.6

Crushing and screening system
Coal received shall be screened and crushed to the required size of the mill
system in the crusher prior to sending to boiler bunkers.
Adequately sized surge hopper, with feeder chutes/flap gates, shall be
provided to have maximum flexibility in the flow of coal.
Two crushers shall be provided (one as standby).
Crushers shall be of suitable heavy duty impact type. Crusher and screens
shall be supported suitable and isolated from other foundation work.
Necessary antivibration dampers shall be provided for crushers and screen
foundations.
Screens shall be provided to screen the fines in the coal in order to
minimize loading of crusher. The screening and crushing system shall be
designed for 2 x 100% to meet the requirement and retain flexibility in
operation.
Screens
shall
be
of
heavy
duty
rotary
screen
or
electromechanical screen with unbalanced motor. The capacity of the
screens and crushers shall be suitable for adequate recirculation design
margin.
The screened coal shall be sent to boiler coal bunkers directly.

3.3.7

Bunker feeding system
The capacity of the conveyors system up to bunker feeding conveyors shall
be adequate to meet one day's requirement in two shifts of 8 hours
operation. Samplers and belt weigh scale shall be provided prior to bunker

feeding conveyor with the necessary controls.
Bunker filling shall be done by a traveling tripper conveyor arrangement.
The bunker floor shall be sealed to have effective ventilation system and

tripper arrangement shall be given for bunker filling. This system shall
also include bunker sealing arrangement, bunker ventilation system and
traveling tripper conveyor.
Necessary bunker flooring shall also be included.

3.3.8

Dust extraction/dust suppression/ventilation system
Dust extraction system shall be provided in all the junction towers and
crusher house to minimize the air pollution problem. Process water shall be
used for dust suppression system. I
Dust suppression system shall also be provided to the coal storage area.
Necessary spray system and arrangement shall be provided in both coal
storage areas.
Bunker ventilation shall be provided to extract the dust due to bunker filling
operation.
The system shall be designed for air
particulate matter shall not exceed 0.5 mg/m3.

3.3.9

quality

in

which

respirable

Safety interlocking system
A PC based PLC safety interlocking system for coal handling system shall
be such that sequential starting/shut-down of all the equipment due to trip
condition of downstream conveying equipment is ensured. The trip-off of
the minimum equipment in the safest sequence during abnormal operating
conditions shall be ensured. The functions of safety interlocking system is
as follows:




3.3.10

annunciate/indicate initiating cause for the equipment which has tripped
prevent restarting of equipment until safe conditions are restored
retain flexibility of operation as is consistent with safety

the interlocks provided shall permit one stream operation retaining the
flexibility in operation.

Control room
The inplant coal handling system starting from the crusher up to boiler
bunker feeding trippers operation shall be controlled from inplant coal
handling control room located in the Plant near to crusher house. Other
equipment/components shall be operated from local stations (see also
Chapter 9).

BPDB, Barapukuria Power Plant

Section B3: Coal Handling System

Minimum Requirements

Performance and Design Criteria

Unit

Data

Coal handling system

Bulk density to be considered for capacity calculation

kg/m3

0.65

Bulk density for calc. power of drive

kg/m3

1.0

Safety factor for design of conveying elements and
conveying equipment

1.1

Safety factor for capacity selection of storage equipment

1.0

Capacity of belt conveyors to bunkers shall permit the
transport of the daily (or hours) coal demand to the bunkers
within

hours

4

Max. velocity of belt conveyors

m/s

2.0

Number of streams and capacity for related equipment:

• elevated coal belt conveyor (if required)

1 x 100%

• ground level bell conveyor

1 x 100%

• traversing and reversible distribution belt conveyor

1 x 100%

• coal crusher

2 x 100%

• extension of bunker tripping conveyor
• magnetic separator

2 x 100%
1 x 100%

• belt scale

1 x 100%

• tram iron detectors

2 x 100%

Separating degree of separator (filler), dust suppression
(particulate matter)

mg/m3

0.5

B3/FB-1

BPDB, Barapukuria Power Plant
Section B3: Coal Handling System

Bidder/Contractor

Technical Data by Bidder/Contractor

Unit

Coal handling equipment
Belt conveyors
Type

-

Manufacturer

-

Belt widlh

mm

Height of borders

mm

Handling capacity
Belt velocity

kg/h
m/s

Material of belt

-

Drive power

kW

Coal crusher
Number

pcs

Manufacturer

-

Type

-

Capacity

t/h

Screen dimension

mm

Final grain size

mm

Motors:
• manufacturer

-

• type

-

• rating

kW

• rated voltage

kV

• speed

rpm

Magnetic separator and tramp Iron detectors
Type/ Manufacturer

-

Number'

pcs

Location

-

Rated power

kW

B3/FD-1

Data

BPDB, Barapukuria Power Plant
Section B3: Coal Handling System
Technical Data by Bidder/Contractor

Bidder/Contractor
Unit

Data

Weighing scale
Type
Manufacturer
Capacity
Accuracy
location

_
kg
%
-

Tripper conveyor
Manufacturer
Type of construction
Number
length

_
-

pcs
m

Capacity

kg/h

Width

mm

Belt velocity
Coal bulk density

m/s
kg/m3

B3/FD-2

Air and Flue Gas System

Table of Contents
B4. Air and Flue Gas System
General

4.1
4.2

Scope of Supply and services

1
2
3

Air Supply Systems
Flue Gas System
Electrostatic Precipitator

1
2
34.3
4
5
6
7

General
Air and flue gas ducts and dampers
FD fans and ID fans
Steam air preheaters
Regenerative air preheater (AH)
Flue Gas recirculation fans (if required)
Electrostatic Precipitators (ESP)

Special Technical Requirements

Air and Flue Gas System
4.1 General
The air supply and flue gas system shall be designed in a double flow path.
Each of the components shall be provided twice. In case of failure of any
equipment within the air and flue gas system the steam generator shall be still
able to obtain 60% of its MCR. Dampers in the air and flue gas ducts shall
consider a cross over operation (e.g. operation forced draught fan left side.
regenerative air heater right side)
Provision for flue gas recirculation system for decreasing the NO x emission has
to be provided, if necessary.
4.2 Scope of Supply and Services
4.2.1

Air supply systems
Comprising essentially:








hot air ducts to mills' and burners
2 (two) cooling air fans with electric motors
2 (two) steam-heated air preheaters with condensate drain control
system



2 (two) regenerative type air preheaters including rotor with motor,
gearing, automatic sootblowing equipment, washing device. reserve drive,
rotation monitoring as well as fire alarm device, an extinguishing and
rinsing device with additional washing and rinsing drive
all necessary isolating and regulation dampers with electric actuators,
expansion joints and Venturi measurement devices



4.2.2

2 (two) complete FD fans with electric motor, forced lubrication system

air ducts with reinforcement and support structure comprising
the FD fan and mill primary air fan inlet ducts

the FD fan and mill primary air ducts between the air fans and the
regenerative air preheaters



insulation including cladding



all measures necessary for damping out vibration and for noise
attenuation including silencer.

Flue gas system
Comprising essentially:

B4.





Flue gas ducts with reinforcements and support structure. isolating and
regulations dampers with electric actuators expansion joints, Venturi
measurements devices, etc. consisting of raw gas duct with ash hopper
between the steam generator out- let and the regenerative air preheaterinlet
duct, from the regenerative air preheater exit to the inlet hood of the
electrostatic precipitator (ESP), clean gas duct from the exit hood of the
ESP to the induced draft fan (ID fan), common duct between ID fans and
further to the stack inlet



2 (two) ID fans (with special type impeller blade considering 100% ash
with flue gas causing no damage or unbalance) including electric motor,
forced lubrication system



2 (two) flue gas recirculation fans including electric motor arrangements
for minimizing NOx formation, if necessary



all necessary isolating dampers (for all ID fan, Coal mill, ESP, flue gas
recirculation fans for plant running maintenance) and regulation dampers
with electric actuators. expansions joints

insulation including cladding


all measures necessary for
attenuation including silencers.

damping

out

vibrations

and

for

noise

4.3 Electrostatic precipitator (ESP)
Comprising essentially:









steel supporting structure
gas tight steel casing

hoppers and chutes including spray electrodes.
including motors
electrical equipment
control system with cubicles, analog and binary equipment
walkways, ladders. stairs
heat insulation
electric tracing for all ash hoppers.

rapping

equipment

4.3 Special Technical Requirements
4.3.1 General
The air flue gas system shall be of the balanced draft type and designed
in two parallel lines. The system shall be completely gas tight.
All the equipment shall be of the high efficiency aerodynamic design
silent in operation vibration free and must guarantee complete safety in
service. All fans shall be dynamically balanced in the factory.

The flues and ducts shall be adequately supported and shall be
provided with necessary inspection access, observation and cleaning
doors shall, be provided to give access to flues and ducts for
inspection and maintenance. These doors shall be gas tight under all
working conditions.' Each inspection door has to be equipped with
one small observation flap which can be opened and closed withoutany tool. The
inspection
doors
have
to
be
provided
for
inspection
of
each heating surface at flue gas inlet and outlet.
All necessary gas flues and air ducts shall be provided including
auxiliary
plant.
Wherever
necessary,
balance
ducts
fitted
with
isolating dampers shall be provided. It shall be so arranged to
maintain an even draught across the width of the boiler unit at the
exit from the boiler.
All flues and ducts shall be designed to give an equal distribution of
gas and air flow to the various portions of the units and freedom from
pulsation, vibration and noise.
Wherever necessary, a series of sampling, measuring and test points
shall be arranged in the flue and duct in approved positions. means
shall be provided for measuring the total combustion air flow.

4.3.2 Air and flue gas ducts and dampers
The expansion joints shall be of steel and suitable insulated. Such
joints shall incorporate internal plates to prevent deposition in the
joints.
Air ducts and gas flues shall be of all-welded construction of steel
plates suitable stiffened by means of angles, tees or flats secured to
the outside. Circular air ducts are preferable.
Ductwork shall be fabricated in sections with flanged ends so that
field erection will require either the end matching and securing of
connecting flanges attached to the adjacent units or welding of the
adjacent flanges.
One (1) Venture throat shall be installed for measuring the air flow of
air heaters primary and secondary air pulverizers hot and cold air and
burners,
Suitable connection shall be provided for permanent instruments and
for check and test purposes. for pressure readings all flue gas
sampling, All ducts shall he designed to minimize resistance to air
and gas flow and to give good distribution or gas and air flow.
The secondary air dampers of the burner must
proportioning of the combustion air to each burner
proved during commissioning tests.
All necessary isolating and control dampers
reliable and convenient operation of boiler unit .

shall be

permit the exact
which has to be
provided

lor

the

Dampers shall be provided to meet the following operating conditions:
• isolation of the steam generator against heat losses when out of

operation with one FD fan etc. and reverse


operation with two (2) regenerative air heaters but one (I) FD fan
respectively one (1) ID fan



to take each burner group into and out of operation



to control the combustion air flow of each single burner.
Dampers to be used for these operation procedures shall be equipped
with electric drives and approved limit switches. The remote control and
interlock system will be supplied under Chapter B9 of this specification.
Dampers must be capable of opera\ion under
pressure
without
binding
or
seizure,
and
shall
devices in the fully open and shut positions.
Except where otherwise agreed,
and mounted in frames, and,
horizontal spindles.

the
be

dampers shall be of
wherever possible/shall

maximum differential
fitted
with
locking
the
be

multi-leaf
arranged

type
with

Dampers in flue gas ducts shall be designed and located so that the buildup of ash behind the damper blade is reduced to a minimum and their
opened and closed position has to be used for the FD fan and boiler
interlocking.
The damper spindles shall be of steel which is sufficient resistant and
special attention shall be given to the design of the dampers. spindles and
hearings to protect them against the ingress of dust/ash and distortion or
deterioration due to high temperature. The bearings of the dampers shall
be located outside and shall he or the self-lubricating type.
Special attention shall be given to the sealing arrangements
dampers to ensure gas and air tightness when in the shut position.
Each damper shall be equipped
unmistakable notch on both shaft ends.

with

a

local

indicator

and

or

isolating

an

easy

Tapping holes
suitably and correctly located for its
purpose
shall be
provided
for
permanent
instruments
and
for
checking
and
testing
purposes for pressure readings and flue gas sampling. All ducts shall be
designed to minimize resistance to air and gas !low and to give good
distribution of air flow particularly to boiler sides and the burner air
registers or to the burner wind box.
The air or flue gas leakage of the dampers when closed shall not exceed 1
% of the maximum flow.
All flue gas dampers which are installed
operation of the unit shall be provided
shall be supplied between the dampers.

for isolation of components during
double. When closed. sealing air

Both
regenerative
air
preheaters
shall
be
provided
with
one
common
bypass on flue gas side so that during cold start-up operation without anyregenerative air
preheater
will
be
possible.
The
flue
gas
damper
in
the
bypass
shall
be
suitably
interlocked
to
avoid
that
the
maximum
permissible temperature of stack will be exceeded.
Due attention shall be paid for the material selection of the flue gas duct in
which during continuous operation the flue gas will be stagnant.
Selection of ducts and dampers within the air and flue gas system shall be
done so that the wet washing of one regenerative air preheater will be
possible. while the boiler will operate on partial load with the other air
preheater
in
operation.
Nevertheless
the
Contractor
has
to
guarantee
continuous
operation
of
the
regenerative
air
pre
heaters
without
wet
cleaning
for
the
duration
stated
under
"Guarantees"
(Guarantee
data
sheets BO/FG).
In general, the air and flue gas ducts shall be interconnected by welding.
Only
in
places
where
maintenance
or
repair
is
required
(dampers,
expansion joints, fans, etc.). flanged connections may be provided.
Air boxes for
fed separately.

burners

shall

Connection between boxes
done by steel expansion joints.

be

designed

so

for

burners

and

that

the

at

least

each

membrane

row

wall

will

be

shall

be

All ducts which are not insulated shall be suitably cleaned and painted for
resistance to corrosion. ducts and flues requiring thermal insulation shall
comply with the requirements of this specification.

4.3.3 FD fans and ID fans
Two (2) FD fans of radial type with backward curved blades shall be
supplied. Each fan shall be designed for a combustion air !low which
corresponds to 60% of MCR when operating with design coal and
20% excess air at furnace outlet. Furthermore, the design of the FD
fans shall allow a margin for fouling of heating surface. The design of
the ID fans shall consider a rise of flue gas temperature and of flow
resistance due to fouling of heating surfaces.
Load operation between .30% and 60% MCR shall he possible with
just one FD fan, one air preheater and one ID fan.
The FD fan shall be capable
partially or completely from outside.

of

drawing

the

combustion

air

in

The control of the fans shall be done by inlet guide vane
controllers (swirl controllers).
The fan casing shall be of approved type and so arranged that a
section of the upper half is easily removable to facilitate the removal
of the fan impeller without extensive dismantling of connecting flues
and ducts. The casings shall be constructed of steel plates with
adequate stiffening to prevent breaking or vibration.
The casing shall be securely braced with structural shapes and all
seams continuously welded. The inlet sections shall be fitted with
inlet cones which also form inlet seals with the fan impeller. The fan
shall be supported on foot angles welded to the extended sides of
the casing. A casing drain not less than DN 50 shall be provided.
All fans shall be suitable for all-weather outdoor operation.
All fans shall be driven directly by a constant speed electrical motor.
Fan and motor shall be anchored on a common foundation of
concrete
with
vibration
dampers,
anchoring
plans
with
foundation
loads to be supplied by the Contractor.
The motors shall
minimum air and
power.
The material
machinery.

for

be designed for operation of the
gas temperature without exceeding

the

shaft

shall

be

thermally

fans also at a
the rated horse

stabilized

prior

to

final

The shaft forged and machined from mild steel or high tensile steel
shall be designed to have its first critical speed not less than 125% of
rated
speed.
The
impeller
shall
be
statically
and
dynamically
balanced before shipment commissioning.
If as a result of electrical black-out there is a total failure of the

cooling water supply, the bearings must be capable of performing
without cooling and be safeguarded against over-temperature.
The sealings shall be preferably of the labyrinth type.
Cooling and heating equipment has to be provided.
All platforms shall be provided to all components of the fan and
motor subject of maintenance.
White metal bearing with forced lubrication shall be provided. The
lubricating system consisting of oil receiver oil heater oil pumps, oil
coolers shall be dimensioned to incorporate the lubrication of the fan
motor too. One complete lubrication unit shall be attributed to each
fan.
For fans operating with flue gas, measures shall be taken to
reduce the fans wear because of dust and fly ash to a minimum.
Inlet and/or outlet silencers shall be provided in order not to exceed
the specified noise level. The silencers shall be of the clement type
so that it will be possible to exchange the individual silencer
elements. The filling c1cments shall consist of noncombustible. heat
resistant damp-proof material.
Fans of smaller capacity (shaft power less than 50 kW) may be
provided with roller bearings and control by throttling will be
acceptable.
The fan casings shall be insulated against heat and noises. The
insulation shall be divided into pre-fabricated sections which can be
easily moved, and comply with the specification of Chapter B06.
Silencers are to be provided on the suction and discharge side.

4.3.4 Steam air preheaters
To ensure that the boiler exhaust gas temperature docs not fall short the
dew point the primary and secondary air shall be preheated by steam air
preheaters.
The steam heated air heaters shall be arranged in each air duct between
FD fan and the regenerative air preheater.
The tube ends shall be welded into mild steel tube plates and the element
supporting framework and headers shall be of all-welded construction.
The position or the steam air preheater shall allow for the complete
draining of all pressure parts.
The heating surface shall consist of finned tube elements which shall be
hot dip galvanized after assembling. Aluminum fins are not acceptable.

The air heater shall be equipped with a 100% bypass at the air side.
Condensate shall be led back to an appropriate point in the feedwater\
condensate system through a trap and a control tank. All steam and drain
piping control and isolating valves. and all other fittings shall be provided
in order to satisfy the above requirements.
Drain condensate pumps of the vertical barrel type shall be provided.
Heating coils shall be easily removable for cleaning and maintenance.
The steam supply can be taken from suitable bleed points on the turbine
(see Heat Balance Diagram). During start-up the steam can be taken from
the auxiliary steam line. The condensate shall be cooled in a cooling stage
at the air inlet to at least 80°C when working at MCR.
Drain connections (blind flanges or screwed plugs) shall also be upstream and down-stream of the steam air preheater in the bottom of the
air duct (not only in the steam air preheater frame).
Condensate pipes shall be valved so that the condensate can be returned
to the unit from which the steam is coming from.
The air temperature control shall be performed by means of steam now
control. located at the inlet of the steam air preheater.

4.3.5 Regenerative air preheater (AH)
Two (2) AHs shall be provided. They shall be designed to cool down
the flue gases to 150°C when operating with coal at MCR with the
designed excess air at furnace outlet of 20%. This design condition
shall take into consideration the leakage of combustion air in the AH
after an operating period of at 'least 1000 hours without adjustment of
the sealing elements. The design air inlet temperature when burning
coal shall be at least 80°C. However, the Contractor shall take into
consideration the sulphur content of coal to avoid corrosion in the
AH.
All provision shall be made to keep the amount of leakage air to a
minimum. The total air leakage of a freshly adjusted AH shall result in
a C02 drop of not more than 1.0 between 60% and 100% MCR.
The AH shall be designed to operate normally in parallel, but if one
AH is out of operation, the other one shall be able to keep the steam
generator at 60% of MCR. The sections for the primary air and
secondary air shall he apportioned in accordance with the primary
air/secondary air flow ratio for the design point.
The AH shall be supplied with vertical shafts, including elements.
casing,
sootblowers,
element
supports.
external
supports.
driving
gears and driving units, forced lubrication equipment together with

coolers
and
all
other
operation of the Plant. .

equipment

required

for

the

safe

The heating elements shall consist of low alloy steel
less than 0.5 mm thickness and shall be properly packed in baskets.

and

sheets

efficient

of

not

The
heating
elements
shall
be
spaced
and
compactly
arranged
within
sectors of the cylindrical housing, but they shall be kept at a fixed
distance
from
each other. The
individual
elements
shall
be
partly or
entirely corrugated or modulated to give a turbulent flow of the gases
and air.
The hot and cold end elements shall be arranged in casings with
removable
compartments
and
the
design
shall
allow
for
the
removal
of
the
cold
and
hot
end
element
baskets
through
access
doors
provided in the AH housings.
At least 300 mm in height of the cold heating elements shall be
enamelled
in
order
to
achieve
longer
service
life.
The
cold
end
elements
shall.
be
properly
packed
in
baskets
and
a
sufficient
number of access door provided for easy and fast replacement. The
Tendered
shall
give
full
particulars
of
the
material
and
estimated
performance
of
the
intermediate
and
low
temperature
sections
and
the
frequency
of
material
replacement.
Electrical
hoist
with
runways
etc. for maintenance and replacement shall be provided.
Each AH has to be equipped with two drives. The main drive is to be
an electric motor through a gearbox or a hydraulic motor. A standby
motor
drive
to
the
same
gearbox
or
hydraulic
motor
shall
be
provided. The drive is to be complete with a self contained lubricating
system
which
shall
include
a
water
cooling
system
facilities
for
manual
rotation
and
rotation
monitor
of
signal
that
the
AH
is
in
operation shall be provided.
For
on-load
cleaning
integral
steam
soot
blowers
for
cold
and
hot
side shall be arranged. The blowing pressure shall be designed with
respect to the thickness of the heating elements. The Contractor shall
take the steam for soot blowing from a source within his limits of
supply.
Steam
blowing
equipment.
bearings
and
other
parts
which
so require. shall be air sealed to avoid infiltration of corrosive flue
gases.
The
sootblowing
device
has
cleaning of the AH heating surfaces.
The
AH
shall
be
equipped
fire
alarm
equipment
display
arranged
for
water
washing
shall be supplied.

to

be

designed

for

the

most

effective

with
fire
extinguishing
devices
including
panel.
The
AH
elements
shallbe
and
all
necessary
washing
equipment

The necessary drainage troughs hoppers, pipes, valves shall be

supplied.
Adequate sealed and illuminated inspection windows for inspection
during
operation
and
removable
door
and
access
ways
for
maintenance and repair shall be provided.
If as a result of electrical black-out there is a total failure of the
cooling water supply. the bearings must be capable of performing
without cooling and be safeguarded against over-temperature. An oil
bearing temperature measuring equipment shall be supplied to judge
the oil temperature.
Possibility of hot end and intermediate AH element inspection and
replacement shall be provided (openings with removable covers in
the ducts above the air heaters. internal beams or hooks for lifting the
elements).
External hoist with trolleys and beams to extract
sufficient length, electrically operated, shall be provided.

the

elements

or

Initial thickness measurement of cold end elements has to be carried
out as spot-checks before commissioning that corrosion resistance
can be proved after 6.000 operation hours by measuring the sheet
thickness again for operational informal ion.
The seals between the primary and the secondary portion shall be
designed like those between the secondary portion and the flue gas
ducts. i.e. with moveable. multi-part, radial sector plates, capable of
following automatically the rotor deformation as well as with shell
seals likewise moveable. Both. the radial and the shell seals shall be
readjustable from outside during operation.
Ten (10) thermocouples up to a local control box shall be supplied for
each AH to judge the cold end element temperature to avoid cold end
corrosion .
The external surfaces shall he insulated in
requirements of this specification (see Chapter B06).

accordance

with

the

before

the

4.3.6 Flue gas recirculation fans (if necessary)
In addition to the general requirements for fans stated
selection of flue gas recirculation fans shall comply with the following:
In order to prevent corrosion during standstill. the flue gas
recirculation fans shall be provided with turning gears.
The recirculation fans shall be interlocked and protected against back
reverse rotation or loss of differential pressure between fan outlet and
supply point to boiler .

4.3.7 Electrostatic precipitators (ESP)
Two ESPs shall be provided for each steam generator. Each ESP
shall be designed for the maximum flue gas flow with at least 40%
excess air in the furnace (ESP capacity= 140% MCR) and a flue gas
temperature of 180°C (in case of AH stop 350°C for 10 min.).
The dust burden of the flue gas entering the ESP shall be determined
by the Contractor.
The ESPs should be arranged behind the AH and before lD fans.
The ESP minimum requirements are:


fields with gas tight casing
• electric heated hoppers with sufficient steep hopper slope to
avoid ash bridging
and sufficient volume
access doors platforms. stairs and inside gangways and ladders
complete ESP internals and rapping devices
supporting structure
thermal insulation
paintings








Electrical part:









transformer rectifier unit with spark control
control panel
discharge electrode supports and rapper insulator
penetrating insulator
insulator heater
portable grounding rod
ESP control centre for enclosed cubicle (indoor use)
all motors .

The spraying electrode shall be made of material that can resist
tension crack corrosion.
The use of wire-type spraying electrodes is not permitted.
Each ESP shall consist of a single steel casing with sufficient equal
mechanical and electrically independent treatment zones in series. It
shall be possible to keep the ESP in service. even when one zone
becomes unavailable. The supporting structure shall be made of
steel.
A corrosion and heat resisting steel grid shall be provided at the inlet
to each precipitator to prevent large pieces of partly burned particles
which may be present to the gas stream. from entering the collecting
zone.

The
spraying
and
collecting
electrodes
shall
be
designed
replacement. , Sectionalized collecting electrodes would be preferred.

for

easy

Dust/ash
loading
shall
be
considered
when
designing
dueling.
To
prevent
the
formation
of
condensed
water
protection
against
freezing.
the
ESP
shall
be
equipped
electrically
operated
heating
system
for
the
complete
hoppers.

raw
and
with
fly

gas
as
an
ash

The
insulator
devices
at
the
HV
electrically and designed for easy replacement.

inlet

passages

shall

be

healed

The gas-tight casings. access doors and peep holes in the casings of
electrical
and
mechanical
connections
shall
be
designed
to
minimize
air leakage into the ESP. Internal pockets or ledges where ash might
accumulate
shall
be
avoided
wherever
possible.
The
rapping
gear
for
the
collecting
electrodes shall
as
far
as
possible be
arranged
inside
the ESP. The intensity and frequency of the rapping shall be variable
and the gear shall operate without undue noise.
Expansion
joint
against erosion.

shall

be

provided

from

steel

with

inside

protection

The Contractor shall take all necessary steps to ensure free ash flow
out of the hoppers. A rapping mechanism which raps intermittently at
the
hopper shall
be
provided
to avoid
bridging of
fly ash
in the
hopper.
The
hopper
shall
be
effectively
dried
out
during
commissioning
and
shall
be
insulated
as
specified
to
prevent
condensation
which
impedes removal of the dust. The dust hoppers shall be provided with
ash bridge -breaking devices of the approved type which shall be a
permanent
fixture
arranged
near
the
outlet
from
each
hopper
and
operable
from
a
platform
underneath
the
hopper
when
the
precipitator is in service.
The hoppers shall be furnished with double rotary locks for isolation.
Special attention shall
across the precipitator.

be

given

to

ensure

uniform

flue

gas

distribution

The
local
control
panel
for
the
precipitator
shall
be
provided
placed
near
the
ESP
and
shall
cont61in
all
equipment
instrumentation
for
both
automatic
and
manual
controls.
There
be remote indication for from this cubicle to the mimic diagram of
central
control
panel
to
indicate
precipitator
operation
status
(e.g.
and OFF). All precipitator and rapping gear fault alarms for the
shall be brought up by a common signal at the control room to
alarm panels.

and
and
shall
the
ON
ESP
all

A safety interlock system shall be provided to prevent
the ESP unless the electrical equipment is isolated and earthed.
The electricity to each collecting
rectifiers
with
independent
high
to ensure maximum efficiency of
be permitted.

each

shall

be

insulator

monitored

The results shall be submitted to the Client/Consultant.

separate
arranged
will not

an

alarm

compartment,

to

each

During commissioning the Contractor shall make measurements to
determine the following:
flue gas distribution across the inlet cross-section of ESP
inlet dust loading
dust size distribution before ESP
dust properties
dust size distribution alter ESP
dew point of the flue gas.

into

and

All electrical heating of the precipitators shall be under thermostatic
control on the 'local panels. The temperatures of the heated surfaces
shall be monitored and in case of low temperature, provision shall be
made for alarms which will be raised at the ESP control panels.








access

zone shall be supplied from
voltage
automatic
controls
ESP. PCB filled transformers

The dust level in the ESP hopper
given if the dust level becomes too high.
Access
shall
be
provided
to
hopper and before and after each field.

any

Bidder/Contractor
BPDB, Barapukuria Power Plant
Section B4: Air and Flue Gas System
Section B4: Air and Flue Gas System
Technical Data by BIdder/Contractor
Technical Data by BIdder/Contractor
Air flows

Bidder/Contractor
Unit
Data

Unit

At ID fan suction side

Data

mbar

Forced draught fan

m3/s

Primary air fan At stack Inlet
Flue gas recirculation fan Inlet

m3/s

mbar
mbar

Flue gas flows Flue gas recirculation fan outlet

mbar

Regenerative air preheater primary side:

Air
0
Barapukuria
Power Plant
wet/dry (m3 at 0 BPDB,
C, temperatures
1013
mbar)
Ambient B4: Air and Flue Gas System
Regenerative airSection
preheater secondary side:
Primary steam
air heater outlet
3
Technical
Dataheated
by BIdder/Contractor
wet/dry (m at OC, 1013 mbar)

Sealing and cooling air fans

Secondary steam heated air heater outlet

Flue gas recirculation fan:
Regenerative air healer outlet:
0
wet/dry (m3 at 0 Manufacturer
C, 1013 mbar)
• Primary part
Type
Stack inlet:

• Secondary part
Number

Pulverizer
inlet
0
of bearing
wet/dry (m3 at 0 Type
C, 1013
mbar)

Air pressure

FD fan outlet

m3/s
m3/s

°C
m /s
m3/s

Unit °C

m3/s
m3/s

-

3

°C

°C

-

- °C

m3/s
m3/s

Fan
speed
Forced
draft fans
Inlet temperature
Manufacturer

Bidder/Contractor

°C
rpm

mbar

0

C

Steam air preheaters

Secondary steam air heater outlet
mbar
Number
Manufacturer
Primary air fan outlet
mbar
Number
of steam air preheaters
Type of construction
Downstream of air preheater:
Heat
exchange
area
Capacity
of each
(m3 at 00C. 1013 mbar) at design Point
• Primary side Steam mass flow rate
• Secondary sideTotal pressure head at design point Type of air inlet controlmbar
Steam pressure at inlet
Type of bearing
Upstream of air Condensate
preheater: temperature at outlet
• Primary side Number of air inlets
mbar
Combustion air mass flow rate Combustion
Fan efficiency at MCR
• Secondary side
mbar
Combustion air temperature at inlet
Power consumption at MCR
Before burners
mbar
Combustion air temperature at outlet
FD fan motor:
Pressure
loss on the combustion air side
• Manufacturer

Flue gas pressure

Tube•material
Combustion chamber
Power
Forms of tubes (oval or round)
Before superheater • Related voltage
Fin material
Before economizer
• Speed
Pitching of fins
Before air preheater • Cooling water consumption
Thickness of fins
Before ESP
B4/FD-2
Weight
B4/FD-1

mbar
mbar
mbar
mbar

-

-

pcs

pcs 2
mm/s

kg/s
mbar
bar
0

C
pcs

kg/s
0

C

%
kW

0

C

bar
- kW
kV
rpm
mm

kg/s

mm
mbar

t

Regenerative air preheater (RAH)
Manufacturer

-

Number

pcs
-

Type
Heat exchanged

MW

Total heating exchange area

m2

Hot end layer height

m

Cold end layer height (ceramic/enamelled)

m

Stator diameter resp. rotor diameter

m

B4/FD-3

Data

BPDB, Barapukuria Power Plant

Bidder/Contractor

Section B4: Air and Flue Gas System

Unit

Data

Hot end plate thickness

mm

Cold end plate thickness

mm

Material of the hot end plates

-

Material of the cold end plates (ceramic/enamelled)

-

Inlet flue gas flow rate with particlates

kg/s

Outlet flue gas flow rate with particulates

kg/s

Inlet combustion air flow rate

kg/s

Outlet combustion air flow rate

kg/s

Total weight incl. motor

t

Inlet flue gas temperature

o

C

Outlet flue gas temperature

o

C

Inlet combustion air temperature

"c

Outlet combustion air temperature

"c

Minimum mean heating surface temperature at cold end layer outlet

"c

Rotational speed

-1

mm

• Manufacturer

-

• Type

-

• Rating

kW

• Rated voltage

kW

• Speed

min-1

Cleaning equipment for RAH
-

Manufacturer

-

Number of sootbloers per RAH
Type

-

Duration of one sootblowing cycle

min

Operating time of a sootblower per cycle
Steam consumption per sootblower and cycle/AH

min
kg

Steam consumption of all sootblowers and cycle/RAH

kg

Number of sootblower cycles per day

B4/FD-4

BPDB, Barapukuria Power Plant

Bidder/Contractor

Section B4: Air and Flue Gas System
Technical Data by Bidder/Contractor

Unit

RAH washing installation

Data

-

Washing medium
wash water flow

kg/s

Duration of washing process

h

Wash water pumps
Manufacturer

-

Type
Number

pcs

kg/s

Flow rate

Induced draught fan (ID fan)

pcs
-

Number of ID fans per boiler
Manufacturer
Type

-

Delivery capacity at design point

mbar

Total pressure head at design point

kg/m3

kg/s

%
kW

Density of flue gas (STP)
Efficiency at MCR

o

Max. allowable flue gas temperature

C

Type of controller

-

Gearbox manufacturer

-

Type

-

Range of control
Weight per fan and motor

t

Motor:
• Manufacturer

-

• Type

kW

• Rating

kV

• Rated voltage
• Speed
Cooling water consumption

B4/FD-5

• -1

min
kg/s

BPDB, Barapukuria Power Plant

Bidder/Contractor

Section B4: Air and Flue Gas System
Technical Data by BIdder/Contractor

Unit

Flue gas recirculation fan (if necessary)

-

Manufacturer

-

Type of construction
Number of fans
Capacity of each (m3 at O0 C. 1013 mbar)

pcs
m3/s
m3/s

Capacity of each

BPDB, Barapukuria Power Plant

Bidder/Contractor

Static head

mbar

Section B4: Air and Flue Gas System
Technical
Data
by Bidder/Contractor
Type of inlet
control
Fan motor:
Discharge electrodes

Unit

• Manufacturer
Type

-

Thickness

mm

• Power
•Material
Rated voltage
Number per treatment zone

Data

-

Data

kW

kV

-

Speed

rpm
kg/s

Total number per unit

Cooling water consumption

Electrostatic
(ESP)
Effective
lengthprecipitator
between
• plates

Manufacturer

mm

• pitch

mm

Minimum flash over distance between electrodes

mm

Number of ESP
Number of treatment zones in series per ESP
Specific of
absorption
surface
Number
HT sets per
zone

pcs
pcs
m2/m3/s

Collecting
electrodes
Number of HT
sets per unit
-

T ype of rectifier

Type

Thickness
Type
of rapping gear
Collecting
Material electrodes

mm
-

-

Discharge
electrodes
Number per
treatment zone

-

Frequency
or rapping
Total number
per unit

-

Steel casings

Effective height
Projected area per zone
Thickness

mm

m
m2

Total projected
area per unit
Casing
design temperatures

°C

m2

Effective
area static
per unit
Casing
design
gas pressure

mbar

m2

T ype of insulation / Thickness of insulation

mm

Pitch

B4/FD-6
Method of insulation attachment
Type of external finish

Hoppers
Number of dust hoppers per precipitator
Capacity of each dust hopper

t

Tolal capacity of dust hoppers

t

Dust density on which above is based

kg/m3

Thickness of hopper plates

mm

B4/FD-7

mm

BPDB, Barapukuria Power Plant
Bidder/Contractor
Section B4: Air and Flue Gas System
Technical Data by Bidder/Contractor

Unit

Type of heating of hopper (total hopper)
Type of rapping gear

-

Type of rapping

g/m3

ESP outlet dust burden at STP (dry) adjusted to 5% CO2
CO2 content

%

Gas temperature

°C

Gas volume at inlet conditions
• dry

m3/s

• wet

m3/s

Carbon content of dust
Density of dust

%
g/m3

Anticipated dust burden at (STP, dry)
• furnace outlet

g/m3

• ESP inlet

g/m3

• ESP outlet (at 5% 02)

mg/m3

Collection efficiency of ESP

P/o

Gas velocity in treatment zone

mls

Treatment time
Draught loss
Temperature drop in ESP
Rated capacity of each HT set
Ash discharge capacity In case of silo loading
B4/FD-8

s
mbar
°C

kW
t/h

Data

Ash Handling System

B5. Ash Handling System
5.1 General
5.2 Scope of Supply and Services
5.2.1
5.2.2
5.2.3

Bottom as removal system
Fly ash removal system
Ash slurry system

5.3 Special Technical Requirements
5.3.1
5.3.2
5.3.2.1
5.3.2.2
5.3.2.3
5.3.2.4
5.3.3
5.3.3.1
5.3.3.2
5.3.3.3
5.3.3.4
5.3.3.5
5.3.3.6
5.3.3.7
5.3.3.8
5.3.3.9
5.3.3.10
5.3.3.11

General features
B ottom ash removal sy stem
Crusher
Bottom ash bunker
Ash hoppers. gates and dust isolating valves
Belt conveyors for ash handling
Fly ash removal system
Jet conveyors
Intermediate fly ash bunker (if necessary)
Pressure vessel ash conveyors
Air slides
Rotary seal and traversing chutes
Heating system
Flat isolating valves
Exhaust air filters. exhaust fans. air supply system
Fly ash silo
Compressed air system
Slurry pumps. waste water pumps

5.3.4

Pyrite removal (pulverizer rejects)

B5 Ash Handling System
5.1 General
The design and supply of the ash handling system shall include all ash
handling equipment necessary to remove the ash from following sources:






furnace (bottom ash)
pulverizer rejects
economizer
regenerative air preheater (AH)
ESP
Basically the ash handling system is subdivided into a pneumatic and
hydraulic conveying system.
The ash from the furnace pulverizers and economizer shall be integrated into
the bottom ash removal system.
The ash from AH shall be conveyed to a ash mixing vessel/ash conveyor pump
slurry pump). By this ash slurry pump the ash shall be pumped via pipe lines to
the ash settling pond.
The ash from the ESP and economizer shall be transported by a pneumatic
conveying system.
This specification covers the systems required for extraction transportation within
the boundary or the power station storage and for lading of the bottom ash and fly
ash together with the relevant ancillaries corresponding to the design date of this
section (data sheets B5/FB).

5.2 Scope of Supply and Services
This section sets out the scope of the installations covered by this specification as
well as requested supplies and services but without excluding other necessary
components and services not mentioned.

5.2.1 Bottom ash removal system
Comprising essentially:







1(one) drag link scraper ash/slag extractor complete with driving unit for
variable speed air tight casing tensioning device for drag link all electric drives
base frames. steel structure, etc designed for operation with process water
ash/slag chute for feeding the scraper conveyor
complete process water cooling system
connecting pipes separating valves. controls to the process water circulating
system
complete ash, slag crusher including gear, motor coupling base plates and
anchoring holts












complete ash conveying system starting from ash/slag crusher outlet up to the
bottom ash silo inlet including belt conveyor tripping conveyor (or shuttles)
driving units complete with gear and motors
protection devices corner tower und transfer stations (if necessary), supporting
structure together with galleries stairs, gangways, cladding of steel structure.
structural members Il)r fixing lining appliances for dismantling of various components
bottom ash silo including lining, steel support structure, shut-off gate,
loosening and discharge equipment, hopper, all mechanical, electrical and
control equipment associated with the silo
protection facilities to protect equipment against the adverse effect of process
water
drag link conveyor below the bottom ash silo
truck unloading facilities
hydraulic ash discharge including mixing vessel.

5.2.2 Fly ash removal system
Comprising essentially:



















ash hoppers under the second flue gas path (if any) regenerative air
preheater and ESP including one manually operated shut-off valve and one
automatic opening gate for each hopper
complete electrical trace heating system to all hopper, ash chutes, rotary
locks, cellular wheel sluices
jet conveyors for each extraction hopper together with compressed air cock
and fans for jet conveyors (one 100% standby) including base frames electric
motors. Sound attenuation facilities (silencers. sound insulation)
all interconnecting pipe work and valves for jet conveyor air
all connecting pipes from the jet conveyor up to the intermediate fly ash
bunker
Intermediate fly ash bunker, together with cyclone separator for waste air
purification; electrically or pneumatically actuated gates to be installed under
the bunker and electric heating facilities for heating of the bunker hoppers
ash pressure vessel conveyors (one in standby) consisting of pressures
vessels ash inlet valve air intake valve control and vent valves drainage
valves pressure nozzles and all sensors actuators and instruments for
functional group control
rotary air compressors inclusive bed plates anchoring bolts coupling electric
motors, silencer, air suction, filters non return valves, safety valves, air
coolers air storage tanks. all necessary instruments and sound attenuating
insulation (if required)
fly ash silo waste air filters of the bag filter type, including filler with bunker
mounting collar, rappers with actuators, suction and scavenging air fans,
inclusive coupling and motors
all necessary interconnecting pipe lines and valves between ash pressure
vessel conveyor, intermediate bunker, fly ash silo rotary air compressors blowoff silencers .
fly ash silos including lining, steel support structure, with bottom fluidizing
equipment (fans, gates, pipes, hopper, all mechanical electrical and control

equipment associated with the silo).

5.2 Ash slurry system
Comprising essentially:


Ash/water mixing vessel with all associated equipment






pump service vessel
ash slurry pumps with electric drive. flexible coupling
piping for mixing water
ash slurry transport system with all necessary pipeline work valves etc.

water recirculation system from ash pond to ash/water mixing vessel including
recirculation water pumps
facilities for drainage and cleaning of the slurry pipelines
pipeline scraper.




5.3 Special Technical Requirements
5.3.1 General features
The design of the fly ash and bottom ash (slag) handling system shall be based
on the following considerations:
The ash and slag disposal are (ash settling pond) will be located inside the boundary of the Power Station. There for transportation or ash and slag shall be made by
suitable conveyor systems. Silo discharge facilities for bagging (50 kg bag) and
truck Ioading has also to be provided.
The location of storage and loading facilities (silos, bunkers. etc.) shall allow a
centralized handling or fly and bottom ash irrespective or the design/system
variant chosen. The arrangement of these facilities shall not interfere with the
operation area of the boiler.
All possible measures shall he taken to protect components which are coming into
direct contact with process water against its adverse effects (use of material, etc).
The ash handling system shall be designed and constructed in view of a "dust
free" operation.
The ash handling system shaII be operated fully automated.
Fly ash shall be collected from the flue gas pathes of the steam generator (if
applicable), the air hoppers and from the hoppers of ESP. It shall be envisaged
to conveyed as much as possible fly ash with pneumatic conveyors. A dense
lean phase dry pneumatic system (e.g. air slide) under each fly ash hopper to
convey the fly ash to the fly ash silo shall be installed.
The discharge of the ash resulting from some of the above points into the
bottom ash removal system will also be accepted, provided the ash
temperatures necessitate it for safety requirements.

In order to prevent clogging of ash in bunkers, silos and lines appropriate
measures such as provision of ash fluidizing air, lining (or manufacturing from
special material) of the bunker bottoms, etc shall be taken.
When selecting the individual equipment special attention shall be paid to
resistance against erosion. Suitable erosion resistant linings (e.g. for bottom ash
hoppers, slurry pipes, etc.) shall be provided.
The air slide fluidization and conveyor air are each generated in two ventilators
respectively compressors whereby one is "on standby", the air shall be dried
and, if necessary, heated. The fly ash silo shall be isolated and heated.
The 4 (four) ventilators (compressors) for the two pneumatic conveying systems
are parallel connected to a pipeline, so the four ventilators /compressors can be
spare for each other.
In order to limit the wear-and-tear in the conveyor piping, the following
precautionary measures are taken:
•low conveyor speed/velocity
•large wall/thickness
•lining of the pipe elbows which are easily replaceable.
Insofar as the conveyor piping is place over long distances in the open
atmosphere. These parts are to be isolated.
All the pneumatically charged intermediate and collecting silos and loading silos
are each equipped with two exhaust air Filters - designed as bag filters and two
exhaust air ventilators, of which one or each is "on standby". Exhaust air
installations in the open air shall be enclosed.

5.3.2 Bottom ash removal system
The relevant equipment shall perform the following tasks:
•extraction or the bottom slag/ash from the furnace
•preparation of the bottom ash for transport
•transport and settling of slag/ash
•bagging and loading into trucks
The bottom ash from the furnace drops into a drag link scraper extractor.
Ash extraction from the furnace shall be accomplished in continuous
operation. The drag link scraper extractor conveys the bottom ash from
the process water filed slag extractor box to a slag/ash crusher. A suitable
conveyor system transports the slag to the bottom ash silo. Construction
(e.g. number of components, elevation, etc.) and accessories shall ensure
the decantation of water and the loading into trucks.

The bottom ash slag removal system has to be designed for worst coal
operation. The submerged scraper conveyor is to be constructed in such away that
the wet slag can be cooled in the water basin and extracted by
conveyor equipment without a problem at all boiler loads and the total coal
range.
Floating ash/sing is to be prevented by means of a corresponding arrangement of
water spray.
One submerged scraper conveyor is to be arranged under each ash/sing chute of'
the boiler furnace. The submerged frame in the water basin must guarantee an
absolutely tight seal against air ingress into furnace.
The drag link scraper ash/slag extractor shall be of the semi-wet type. The lowest
part of the conveyor shall be located under the furnace hopper. Consideration shall
be made with regard to the relative expansion of the furnace and the drag link
scraper and to exclude the intrusion of false air via the extractor into the boiler.
Bottom and side walls of the extractor shall be lined to avoid excessive erosion.
The quenching water shall be injected into the conveyor in the part were the slag is
falling into the water bath in order to smash the big pieces of slag.
The removable submerged scraper conveyor is to be manufactured in welded
plate construction with profile stiffening brick lining cooling water overflow basin
including water discharge pipe (including draining equipment).
The drive motor of the conveyor chain is to be connected to a hydraulic item and
via elastic coupling to a step-down transmission. By means of a continuously
variable adjustable gear the conveyor speed shall be adjustable to the respective
quantities of ash/slag as to minimize wear.
The capacity of auxiliaries shall be selected under the consideration that for load
changes the ash flow may reach three times the ash now at normal continuous
operation. Due to the above the conveyer shall be equipped with drive with
variable speed and with safety clutch.
The slag extractor shall be equipped with a device enabling to change over from
dumping on the conveyor belt to dumping into a small hopper from which the
bottom ash can he taken over by a trolley.
Suitable openings for inspections shall be provided.

5.3.2.1 Crusher
The crusher shall he provided with dust proof shaft passages. Casing doors shall
with quick look for checking and exchanging wear pans.
The shaft shall be supported from both sides in amply sized and dust proof self
aligning roller bearings.

For conveyors or short length, fixed installed tension devices may he used while
for conveyors of longer length tension carriages or equivalent self-regulatingtension
devices to be used.
Corner towers if necessary) shall consist of steel frame work and outside
cladding. Intermediate stairs and steps shall be provided with grid floorings.
Above the conveyor heads or take-up stations respectively trolley beams for a
payload of 3 tons shall be provided. The bottom ash supply into bottom ash
bunker shall be done by means of a horizontal tripper conveyor. For drives,
brakes, etc. the general provisions stated in other specifications for cranes and
hoists will apply.

5.3.2.2

Bottom ash bunker
The bottom ash bunker associated to the mechanical ash handling system shall
fulfill the following requirements:
Inclination of bottom, lining of bottom and loosening and discharge facilities shall
be selected in order to exclude clogging of the bunker to the maximum possible
extent. The bottom ash bunker shall be of welded construction from steel plates.
Provisions shall be made for draining the rest water of the bottom ash. Bunker
shall be designed to be suited for loading into trucks. Truck loading may be
performed. Feeders for truck loading shall be provided with electrically or
pneumatically actuated shut-off devices and rubber chutes.
For decantation of water and for storage and/or loading also separate bunkers
or
separate compartments of one bunker may he used.
Because the system operates with process water, bunker shells shall be of
suitable material.

5.3.2.3

Ash hoppers, gates and dust isolating valves
Each fly ash hopper shall be fitted with two valves: one gate shut-off valve hand
wheel operated and one automatic opening gate (with pneumatic or electric
actuator).
The transfer chute with built-in grate (e.g. light mesh size of about 100 x 100 mm)
and a flap to a belt conveyor connected down stream is to be installed behind
the scraper conveyor. In case ash/slag parts do not fall through the above grate,
they are to be directed from the grate to a crusher, to be crushed and then also
transferred on to the belt conveyor.
The crushing tools shall he manufactured from highly wear resistant special
material. The bearings shall he manufactured so as to prevent the ingress or dirt
and ash/slag granules.
Between electric motor and gear a flexible coupling shall be provided, while between gear and crusher slipping clutches are required.

5.3.2.4 Belt conveyors for ash handling
Wherever applicable, the belt conveyors must be lodged in closed conveyor
bridges.
A unilateral walkway with open grid flooring shall be provided parallel to all
conveyors. Idler sets shall be provided with labyrinth seals and shall run true.
Bearings shall be of the maintenance free type, i.e. lubrication shall be required
not more frequent than once per year.
Drive pulleys tail and take-up pulleys shall be of closed design.
Pedestal bearing shall be provided with labyrinth seals.
Belt scrapers shall be arranged at the discharge pulley and, if necessary, for
tail pulleys.
Material and construction of covering plates between upper and lower discharge
hoods and product guides shall be chosen in view of optimum sliding behaviour
of the product, avoidance of clogging and limitation of noise. Material shall be
stainless steel, reinforced fibre glass or equivalent. Rubber aprons for guidance
shall be provided.
Gears shall be of the lip on type. Flexible or hydraulic start-up couplings
(depending on requirements) shall be used.
Retention assemblies such as limit switches, true run switches, belt monitors,
lanyard switches shalI form part of the mechanical equipment of the
conveyor plant

5.3.3 Fly ash removal system
The fly ash handling system shall be of the pneumatic type.
The ash accumulated under the boiler second path (if applicable), at the air pre
heater and under the ESP shall be discharged pneumatically in continuous
operation by means of jet conveyors. If necessary, the jet conveyors shall
deliver the ash into an intermediate bunker. The intermediate bunker shall be
arranged near to the steam generator. Compressed air for the air jet conveyors
shall be supplied by two rotary fans (one of which will serve as standby). For
heating up of the conveying air a steam coil air heater (or an electric heater)
shall he provided.
The transport of the ash from the intermediate bunker and fly ash silos shall be
made by conveying systems suitable for transport of fly ash over longer
distances (so called "air pressure vessel conveyors"). The fly ash shall be
conveyed to a joint fly ash silo and loading plant which serves both units.

Exhaust air from intermediate bunker and fly ash silo shall be removed via
adequate filters. At the fly ash silos exit, the ash shall be wetted by a
humidifyingworm conveying system using process water. For fly ash silo fly ash
fluidization
shall he provided.
The following requirements have to be considered by the Contractor:






all the pressure vessel conveyors, conveyor lines and switch points are
to be provided for 100% quantity at five conveyor cycles per hour

the exhaust air filter unit-located on the intermediate bunker (if necessary) is
to be supplied redundantly

all the bends and loops in the conveyor lines to the fly ash silo are to be
provided with wear protection lining (fusion-cast basalt)

all the service and instrumentation air stations are to be designed
redundantly in total

the service air for low pressures up to 1.5 bar is to be generated by rotary
piston blowers; the service air for higher pressures and the instrument air
are to be generated by screw type compressors. All the compressors must
be completely designed as dry running compressors

air receivers and adsorption dryers are to be connected down stream of the
screw type compressors; air heating is 10 be provided for the rotary piston
blowers (if necessary)

all the units are to be provided with a sufficient number of inspection, poker
holes and drain holes

all fly ash pipes have to be equipped with tube connections (studs) and
valves for blowing fee the pipes in case of blockages

all hopper gates, ash chutes, rotary locks, air conveying chutes, etc. are
to be equipped with electrical heating systems (if necessary)
all ash silos have to be equipped with anti-bridging devices

all fly ash conveying equipment, the complete exhaust air filter unit as well as
the piping with heated air are to be provided with insulation as well as
insulation cover plates

exhaust fans connected down stream of the exhaust air fillers are to be
equipped with vane controllers to keep the vacuum in the ash silo constant

a sufficient number of duct isolating valves are to be installed in the air
slide system so that certain chute sections can be closed for repairs
during operation

fine meshed grates above the duct cloths installed in the air slide are to be
provided.
fans and blowers must be designed with two bearings

shafts of dust conveying units must in addition to the usual seals, also be
provided with grease seals to avoid dust exit (with arrangement of
bearing and seal in and housing).

5.3.3.1 Jet conveyors
Jet conveyors shall be designed for the maximum flue gas temperature
prevailing at their branch point. One separate jet conveyors shall be attributed to
each ash extraction point. Above the jet conveyors electrically (or pneumatically)
operated shutoff gates and pipe switch points for optionally discharging the wash

water or ash shall be arranged.

5.3.3.2

Intermediate fly ash bunker (if necessary)
Intermediate fly ash bunker shall be of welded construction from steel plates.
The intermediate bunker shall be equipped with a cyclone separator from where
the waste air shall be laid to the gas duct before the ESP.

5.3.3.3

Pressure vessel ash conveyors
Pressure vessel ash conveyors shall be used for conveying heads which cannot
be mastered by jet conveyors.
Ash pressure vessel conveyors shall be suited for dry (purely) pneumatic
transport of fly ash.
Pressure vessel with all piping connections electrically controlled loading and
unloading fittings inspection doors electrical level measurements including automatic control system shall be provided.

5.3.3.4

Air slides
Air slides are to be provided with inspection glass and hand hole covers at
intervals of at least 3 m.
The insulation must be split designed and be provided with quick action service
locks.

5.3.3.5

Rotary seal and traversing chutes
The rotary seal and traversing chutes are to be equipped with hand hole covers
so that impurities can be removed. The rotary seal sluices arc to be provided
with protruding stub shafts and square shafts so that they can be turned back
by hand for the purpose of removing impurities.

5.3.3.6

Heating system
All the hopper gates in the ESP, collecting bunker coal chutes rotary locks cellular
wheel sluices and air conveyor chutes are to be equipped with steam trace heating
including the necessary isolating valves and condensate separators. If steam is
not available they arc to he equipped as electrical trace heating (at least 400
Watt/m2).
A list showing which plant parts are to be provided with heaters must accompany
the offer.

5.3.3.7

Flat isolating valves
Flat isolating valves - electrically or pneumatically operated - may not be employed
as operational valves in dust conveying plant parts (permitted only as emergency
isolating valves).

5.3.3.8

Exhaust air filters, exhaust fans, air supply system
The exhaust air filters are to be designed as bag filters with compressed air pulse
dedusting, differential pressure monitoring including remote display access doors
exhaust air filter bunkers including electrical trace heaters (400 Wattlm 2) and
exhaust fans including vane controller system,
The two fly ash silos and two storage bunkers are to be equipped with one
exhaust fan and one exhaust air filter each.
Every exhaust air filter shall be designed for the dedusting of the conveyor air from
the pressure vessel conveyor unit of ESPs of both storage bunkers as well as the
exhaust air from loading equipment.

5.3.3.9

Fly ash silo
The fly ash silo shall be of welded construction from steel plates.
Inclination of bottom, lining of bottom and discharge and/or ash extraction devices
shall he selected to exclude clogging to the maximum possible extent.
For loosening of ash each silo shall be provided with a bottom fluidizing system
operating with air.
The fly ash silos shall be air tight and shall be protected with bunker over
pressure/under pressure flaps.
Arrangement of silos shall permit direct loading of ash into trucks or rail wagons.
The silos shall be equipped at the outlet with a gate and humidifying system (worm
or equivalent).
Optionally the fly ash shall be carried from the ash silo to the drag link conveyor
below the bottom ash silo. By this conveyor, the fly ash is fed into the mixing
vessel at the hydraulic ash system.

5.3.3.10

Compressed air system
Compressed air supply systems or slides intermediate pressure vessel conveyor
and fly ash collecting hunker pressure vessel has to he supplied.
Three complete rotary piston blower stations (one of which is to be a 100%
standby) with electrical air preheating, the necessary piping and all fittings as well
as suction and discharge silencers and filters. The air should be generated oil
free.
Air supply of boiler and ESP hopper is to be equipped by three complete
screw-type compressor stations (one of which is to be a 100% standby
including piping all fittings as well as suction and discharge silencers and
filters. Cooling shall be made by dosed auxiliary cooling water. Material of
cooler shall be selected accordingly.

This also includes all the piping to the jet conveyors as well as their continuation
to the fly ash silo, respectively intermediate bunkers including all fittings and the
jet conveyors.
The compressed air stations are to be designed in accordance with state-of-theart technology, including for example standby quick throw-over switches, dryers,
storage basins and condensate discharge lines as well as electrical binary and
analog measurement equipment.

5.3.3.11 Slurry pumps, waste water pumps
The pumps mentioned above shall be able to handle ash slurry and dirty water.
Therefore pumps with low speed (low circumferential velocities) shall be selected.
Number of pumps shall be selected according to the function of the specific
physical arrangement. All pumps shall be provided with double capacities.

5.3.4 Pyrite removal (pulverizer rejects)
The pyrites collected ill the pyrite container of each mill shall be conveyed to
the bottom ash handling system by belt conveyors and/or hydraulic conveyors.
Parts having a particle size larger than 40 mm shall be removed manually
using a trolley.
BPDB, Barapukuria Power Plant

Minimum Requirements

Section B5: Ash Handling System
Performance and Design Criteria

Unit

Data

Data for equipment capacity selection
Coal

as per Annex

Boiler rating for capacity determination of ash handling plant

MCR of boiler

Safety factor for design of conveying elements and equipment

1.1

Safety factor for capacity selection of storage equipment

1.0

Design ash quantities (minimum) for removing elements
• combustion chamber

%

25

• second pass/air pre heater
• ESP

%
%

15
90

Net storage capacity of bottom ash bunker corresponding to the ash
production at MCR

days

2

Net storage capacity of fly ash bunker corresponding to the ash production
at MCR

days

2

Net storage capacity of the intermediate fly ash bunker corresponding to the
ash production at MCR

hours

8

Net retaining capacity of the hoppers of the ESP corresponding to the ash
production at MCR

hours

4

Capacity of bagging system and truck loading devices shall permit the
emptying of the bunker content within

hours

4

Max. velocity of belt conveyors

m/s

2.0

Minimum number x capacity for unit related equipment
Drag link scrapper extractor (bottom ash)

1 x 100%

Ash/slag crusher

1 x 100%

Ash bell conveyor up to bottom ash silo

1 x 100%

Bottom ash silo

1 x 100%

Fly ash silo

1 x 100%

Jet conveyor air fans (if any)

2 x 100%

Jet conveyor air preheater (if any)

1 x 100%

Fly ash pressure vessel conveyors

2 x 100%

Rotary air compressor

2 x 100%

Ash slurry pumps
Water recirculation pumps

2 x 100%

BPDB, Barapukuria Power Plant
Section B5: Ash Handling System
Technical Data by Bidder/Contractor

2 x 100%

Bidder/Contractor
Unit

Operating data
Data shall be filled in for guarantee coal at MCR
Ash resulting from:
• furnace
nd

kg/h

• 2 pass (if any)

kg/h

• air pre heater

kg/h

• ESP

kg/h

• rejects of coal mills

kg/h

Total amount of ash

kg/h

Bulk densities considered for calculation:
• dry combustion chamber ash (bottom ash)
• dry fly ash
• rejects of coal mills
• humidified fly ash

kg/
m3
kg/
m3
kg/
m3
kg/
m3

• moist ash from combustion chamber

kg/
m3

• specific gravity of bottom ash

kg/
m3

Bottom ash handling system
Electric power demand
Instrument air demand

kW
m3/h

Process water demand

kg/h

Data

Drain flow to sewage

kg/h

Fly ash handling system
Electric power demand
Instrument air demand

kW
m3/h

Process water demand

kg/h

Ash slurry system

Electric power demand

kW

Process water demand (hydraulic transportation)

kg/h

BPDB. Barapukuria Power Plant
Section B5: Ash Handling System
Technical Data by Bidder/Contractor

Bidder/Contractor
Unit

Design Data
Bottom ash handling system
Submerged link scraper slag extractor
Number
Type

pcs
-

Conveying capacity

kg/s
-

Turndown range
Gradient of the inclined section

0

Type of chain

-

Chain speed at MCR

m/s

Clearance width of trough
Trough volume referred to max. water lever

m
m3

Motors:
• manufacturer
• type
• rating / rated voltage

-

-

kW/ kV

• speed
Required water quality

rpm
-

Water mass flow rate
Chemical additives (if any)
• type
• quantity

kg/s
-

kg/h

Weight of conveyor

t

Content of sediment in the water

mg/l

Water content in ash/slag at extractor outlet
Crusher for ash/slag
Manufacturer
Type

%
-

-

Data

Number
Capacity

pcs
t/h

Power demand
Bulk density

kW
kg/m3

Screen dimension

mm
mm

Final grain size

BPDB. Barapukuria Power Plant

Bidder/Contractor

Section B5: Ash Handling System
Technical Data by Bidder/Contractor

Unit

Motors
• manufacturer

Data
-

• type

-

• rating

kW

• rated voltage

kV

• Speed

Min-1

Belt conveyors
The Bidder/Contractor shall fill in the following data for each
belt conveyor.
Type

-

-

Manufacturer
Belt width

mm

Height of borders

mm

Shaft centres

m

Handling capacity
Belt velocity

kg/s
m/s

Idler spacing in the upper stand

m

Idler spacing in the lower stand
Drive power

kW

m

Bottom ash silo
Number of silo

-

Type

m3

Net volume
Overall dimensions (length/width/height)
Inclination of bottom
Number of bagging and truck loading connections

m/m/m
0

-

Material
• shell
• bottom lining
Type of bottom ash silo extractor shell
Capacity of bottom ash silo extractor

B5/FD-3

---kg/h

BPDB, Barapukuria Power Plant

Bidder/Contractor

Section B5: Ash Handling System
Technical Data by Bidder/Contractor

Unit

Data

Fly ash handling system
2nd flue gas pass ash removal
Number of tapping points

pcs

Type of gates



Size of gates
Number of jet conveyors
Conveying capacity

pcs
kg/h

Conveying distance

m

Air preheater hopper ash removal
Number of tapping points

pcs

Type of gates
Size of gates
Number of jet conveyors
Conveying capacity

-

pcs
kg/h

Conveying distance

m

ESP hopper ash removal
Number of hoppers
Type of gates

pcs
-

Size of gates
Number of jet conveyors
Conveying capacity
Conveying distance
Jet conveyor air fans (if any)
Number of fans

-

pcs
kg/h
m
pcs

Type of fans
Manufacturer
Air flow rate
Discharge pressure
Motor speed
Rating
Air inlet temperature at MCR

-

3

m /s
mbar
rpm
kW
0

C

BPDB, Barapukuria Power Plant

Bidder/Contractor

Section B5: Ash Handling System
Technical Data by Bidder/Contractor

Unit

Jet conveyor air heater (if any)
Type

-

Number

-

Heat rate
Heating surface

MW
m2

Air inlet temperature

0

C

Air outlet temperature

0

C

Intermediate fly ash bunker (if any)
Number of bunkers

-

Type
Net volume

m3

Overall dimensions (length/ width/ height)
Number of compartments

m/m/m

Number of tapping points from bottom
Inclination of bottom

0

-

Type of outlet gates
Material
• Shell

-

• bottom (lining)
Air pressure vessel conveyors

-

Type

-

Manufacturer

-

Number
Handling capacity of each

kg/h

Conveying distance
3

m

Air demand (m measured in 0 C, 1013 mbar)

m3/s

Air pressure
Rating

bar
kW

Speed

0

rpm

Data

BPDB, Barapukurla Power Plant

Bidder/Contractor

Section B5: Ash Handling System
Technical Data by Bidder/Contractor

Unit

Air compressors for pressure vessel conveyors
Number
Type
Air now rate for each
Delivery pressure

pcs
m3/h
bar

Rating

kW

Fly ash silos
Number of silos
Type
Net volume
Overall dimensions (length/width/height)
Inclination of bottom

3

0

m3
m/m/m

Number of bagging system and truck loading
connections
Material :
• shell

-

• bottom (lining)

-

Fly ash silo exhaust air filter
Type
Manufacturer
Number per Silo
Exhaust air handling rate
Max. temperature

m3/h
°c

Rapper power demand
Motor rating

kW
kW

Motor rating for suction and scavenging air ran

kW

Collecting efficiency of precipitator

%

Silo bottom fluidizing air fans
Number of fans
Type of fans
Manufacturer
Air now rate

pcs
m3/s

Discharge pressure

mbar

Data

BPDB, Barapukuria Power Plant

Bidder/Contractor

Section B5: Ash Handling System

Technical Data by Bidder/Contractor

Unit

Data

Motor speed

rpm

Motor rating

kW

Mixing worm conveyors

Number

pcs

Worm length

-

Product to be handled

-

Conveying capacity

kg/h

Number of inlets

pcs

Rating

kW

Motor speed

rpm

Material:

• casing

-

• worm

-

Process water demand

kg/s

Ash slurry system

Slurry pumps

Number

pcs

Manufacturer

-

Type/arrangement

-

Flow rate per pump
Speed

kg/h
min-1

Rating

kW

Material:
• impeller

-

• casing

-

Slurry water recirculation pumps (if applicable)
Number

pcs

Manufacturer

-

Type/arrangement

-

Flow rate per pump

kg/h

BPDB. Barapukuria Power Plant

Bidder/Contractor

Section B5: Ash Handling System
Technical Data by Bidder/Contractor

Unit
. -i

min

Speed
Rating
Medium handled
Material:


• impeller
• casing

B5/FD-8

1

kW

Data

Water Storage and Treatment
Systems

B6. Water Storage and Treatment Systems
6.1 General
6.2 Scope of Supply and Services
6.2.1
6.2.2
6.2.3
6.2.4
6.2.5

6.2.7
6.2.8
6.2.9
6.2.10
6.2.11

Deep tube wells and pump houses
Raw water storage and supply
Demineralised water treatment plant
Demineralised water storage tank and pumping station
Chemical handling and storage facilities
6.2.6
Dosing system for condensate, boiler feed water and
cooling water conditioning
Condensate treatment system
Potable and service water system
Waste water treatment
Chlorination system
Laboratory

6.3 Special Technical Requirements
6.3.1
6.3.2
6.3.3

Demineralised water treatment plant
Conditioning plants
Condensate treatment plant

6.4 Technical Schedules

B6. Water Storage and Treatment Systems
6.1 General
This specification covers the design manufacturing
complete water storage and treatment system for
power plant.

and supply of the
the entire specified

Discharge water from coal mine after required treatment will be used as
cooling water and the existing deep tube well water will be used for potable
water & demi water production of the proposed 250 MW. At present approx.
1200 MT/ hr is discharged from the Coal mine. Coal mine discharge water
quality is mentioned below:
Sl
no.
1.
2.
3.
4.
5.
6.
7.
8.
9.

Test Item
PH
Conductivity
Iron (Fe)
Silica (sio2)
Suspended Solid
Turbidity
Total dissolved solid
Chloride (Cl)
Hardness

The water storage
following parts


and

Unit
8.35
360 ^s/cm
0.95 mg/l
37.5 mg/l
187 mg/l
3.2 NTU
157 mg/l
9.6 mg/l
2.66 mmol/l
treatment

system

of

this

section

includes

the

Cooling water
Coal mine discharge water receiving system from coal mine discharge
water tank, Clarifiers (2 x 1200MT/ hr), Settling water tank (capacity 5000
m3), Pumps, Coal slurry tank, filters, chemical dozing system, Clear water
tank(capacity 2000 m3), Cooling water supply system, Interconnection with
the existing cooling water system.
Drainage
clarifiers.



system

must

be

incorporated

with

all

tanks/

reservoirs

and

Demineralised water
Raw water receiving arrangement from existing deep tube well system,
Raw water tank (1000 m3), Filters (Fe-Mn filters, Multimedia filters,
Cartridge filters), Clear water tank, RO plant ( 2 x 60 m 3/ hr), Decarbonator
(tank capacity 2 x 200 m3), Mixed bed ion exchanger, pumps, Demi water
tank (2 x 1000 m3), Demi water supply system, Interconnection with the
existing demi water system.

Drainage system must be incorporated with all tanks/ reservoirs.








chemical handling and storage facilities
dosing system for condensate and boiler feed water conditioning
condensate treatment system
potable and service water system
waste water treatment system
chlorination system
laboratory for waste water and coal analysis
The demoralisation water plant shall be sized to serve all demineralised
water consumers of the power generator units and common facilities. The
quality of the treated raw water and condensate shall correspond with the
requirements of the boiler feed water for the heat recovery system and
operation of the associated steam turbine.
The waste water system or this sub-section shall be designed to cope with
the waste water emission regulations.
The design of the water storage and supply systems shall consider
necessary measurements for start-up and commissioning of the power
plant. The requirements specified in BO.3.6 under Section 'Supply and
Services' are to apply.

6.2 Scope of Supply and Services
This section sets out the scope of the installations covered by this
specification as well as requested supplies and services, but without
excluding other necessary components and services not mentioned.

6.2.1 Deep tube wells and pump houses
Deleted
6.2.2 Raw water storage and supply
The scope of this equipment includes the complete raw water supply for
demineralised water , service water, and potable water system. Raw water
storage shall be done by one raw water storage tank.
Raw water tank shall be equipped with 2 x 100% raw water pumps as
supply pumps. The raw water supply to potable water system
demineralised water system and service water within the power plant shall
include a filtration system and the complete piping system to the
consumers valves, fittings and an adequate numbers of taps at the service
water system. Raw water for demineralisation plant, service water and
potable water system shall be existing deep tube well water.

6.2.3

Demineralised water treatment plant
The demineralised water treatment plant is to supply make-up water in
sufficient quantity for boiler feed-water and for the auxiliary cooling water
systems as well as for other consumers, which require high-purity water
by demineralisation of raw water.
Demineralising process shall include Fe Mn filters, Activated carbon filters,
Multi media filters, cartridge filters Reverse osmosis, Decarbonator, Mixed
bed ion exchanging. Capacity of the RO plant shall be at least 2 x 60 m 3/
hr (02 nos., each capacity 2 x 60 m 3/ hr) on the basis of output
(demineralised water production). Demi water production capacity of
mixed bed shall be at least 2 x 120 m 3/hr (02 nos., each capacity 2 x 120
m3/ hr). Membrane of RO plant and resin of mixed bed must be USA/
Europe origin. Colour of anion and cation resin will be different.
Included are chemical storage and dosing tanks, pumps, all necessary
accessories and the complete electrical and instrumentation installation
including one (1) local control panel at the water treatment building with
monitor or mimic diagram indicators alarm systems terminal strips for
transfer signals and all other electrical equipment for closed or open loop
control function.
The instrumentation shall comprise necessary equipment for monitoring
and automatic operation of the plant complete with remote control
devices, push buttons selector switches signal lamps, alarm indication and
electrical wiring.

6.2.4

Demineralised water storage tank and pumping station
The scope of this system includes all work required to install the
demineralised water system including the demineralised water storage tanks
(2 x 1000M3) and pumping station. It includes demineralised water supply
pumps (2 x 100%) instrumentation, valves, piping, fittings, air-resp. CO 2sealing device for storage tank, welding, hangers and supports.
All piping of unconditioned demineralised water shall be 304L stainless steel.

6.2.5

Chemical handling and storage facilities
The scope of this equipment includes the chemical handling and storage
facilities including at least one HCI-storage tank. one caustic soda storage
tank complete with inlet. outlet level indicator drainage manhole vent with
acid
vapour
absorption
transfer
pumps
complete
with
connecting
pipework.
truck
unloading
station
with
unloading
manifold
hose
connections. all necessary equipment and installation for safe operation of
the station and a drum store for dosing chemicals.

6.2.6

Dosing system for condensate. boiler feed water and cooling water
conditioning

Chemical feed - condensate
The
scope
of
this
equipment
includes
the
condensate-chemical
feed
system which will consist of a skid-mounted stainless steel hydrazine and
ammonia feed tanks and dosing pumps (2 x 100%) piping valves fitting
welding.
instrumentation
and
controls,
hangers
and
supports,
two
barrel
pumps with appropriate piping for emptying drums. Both hydrazine and
ammonia will be fed downstream off the polisher vessels to scavenge
oxygen and control pH.
Adequate
space
and
means
for
maintaining
the
provided as well as for controlling containing and treating of spills.

equipment

The condensate
chemical feed
equipment
ammonia and hydrazine feed to the auxiliary boiler.

arranged

shall

be

shall

to

be

provide

Chemical feed - Boiler
The
scope
of
this
equipment
includes
the
boiler-chemical
feed
system
which will consist of a phosphate feed lank with mixer and dosing pumps
(2 x 100%) all mounted on a skid. along with piping valves fillings, welding
instrumentation and controls, hangers and supports.
Adequate
space
and
means
for
maintaining
the
provided. ns well as for controlling containing and treating of spills.
The
boiler
chemical
feed
equipment
phosphate feed to the auxiliary boiler.

shall

be

equipment

arranged

shall

to

he

provide

Water sampling system
Analysis and recording
boiler water and steam
the boiler room. Boiler
and air cooled by air cooler.

for chemical control of the condensate feedwater
systems shall be provided by a sampling station in
sampling station room must be ash free (air tight)

The
system
will
provide
temperature,
pressure
and
now
control
for
continuous
automatic
analysis
and
recording.
The
equipment
will
consist
of freestanding sampling panels, sink, conductivity cells, pH cells, oxygen
analyzers,
silica
analyzers,
sodium
analyzers,
hydrazine
analyzer,
recorders,
components
for
either
returning
samples
to
the
condensate
system
or
dumping
them
to
waste
tubing
piping
valves
instrumentation
and controls.
Grab samples will
be
located in the service building.

carried

back

Samples to be piped to the panel shall include:
1. Condensate pump discharge
2. Condensate at deaerator inlet

to

the

central

sampling

laboratory

3. Condensate deaerator outlet
4. Boiler feed pump discharge
5. Economizer inlet
6. Main Steam
7. Boiler blowdown
8. Condenser hotwell
9. Polisher outlet(after chemical feed)
10.Auxiliary boiler feed pump discharge
11. Auxiliary boiler blowdown
Conductivity measurement and recording shall provided for:

1. Condensate pump discharge
2. Condensate at deaerator inlel
3. Condensate at deaerator outlet
4. Boiler feed pump discharge
5. Economizer inlet
6. Main steam
7. Boiler blowdown
8. Condenser hotwell
9. Condensate polisher outlet(after chemical feed)
10.Auxiliary-boiler feedwater
11. Auxiliary boiler blowdown
pH measurement and recording shall be provided for:

1.
2.
3.
4.
5.
6.
7.

Condensate pump discharge
Condenser hotwell
Economizer inlet
Boiler blowdown
Condensate polisher outlet (after chemical reed)
Auxiliary boiler feedwater
Main steam
Oxygen analysis and recording shall be provided for:

1.
2.
3.
4.

Condensate pump discharge
Deaerator inlet or outlet
Boiler reed pump discharge
Auxiliary boiler feedwater
Silica analysis and recording shall be provided for:

1.
2.
3.
4.

Boiler blowdown
Condensate polisher outlet
Economizer inlet
Main steam
Sodium analysis and recording shall be provided for:
1. Condensate pump discharge

2.
3.
4.
5.
6.

Condenser hotwell
Condensate polisher outlet
Economizer inlet
Main steam
Boiler blowdown
Hydrazine analysis and recording shall be provided for the economizer
inlet and auxiliary boiler feedwater.
Chemical feed - Cooling water
The scope of this equipment includes the cooling water conditioning feed
system which will consist of a feed tank with mixer and dosing pumps all
mounted on a skid along with piping, valves, fittings, welding
instrumentation and controls, hungers and supports.
Adequate space and means for maintaining the equipment
provided. as well as for controlling containing and treating of spills.

shall

be

The cooling water chemical feed equipment shall be arranged to provide
corrosion inhibitor feed to the cooling water system.
According to the bidder's design of the cooling system the quality of the
cooling water has to prevent negative effects by fouling and scale
deposits.
Necessary equipment for treatment of make-up water or dosing of scale
inhibitors are within the scope of supply and services of the bidder.
A detailed technical description of the system and the proposed treatment
equipment has be submitted with the tender documents.

6.2.7

Condensate treatment system
The scope of this equipment includes a condensate treatment system
complete with cartridge filters manually operated by-pass associated
piping, pneumatically operated valves and cartridges, ion exchanger line
designed for treatment of condensate flow rate of 3 x 50%, with cation and
anion ion exchangers, regeneration station, regeneration water pumps,
associated piping and pneumatically operated valves for full automatic
operation and regeneration.

6.2.8

Potable and service water system
Station potable water shall be produced by adding chlorine to filtered raw
water from the raw water system and storing it in a potable water storage
tank (1 x 500M 3). The scope of this equipment includes the potable water
storage tank sized to cover necessary storage capacity of power plant
water and associated housing complex demand 2 x 100% water supply
pumps complete piping system to all potable water consumers.

The quality of potable water shall be further adjusted if required to ensure
that the water has a slightly positive Langelier Saturation Index and is
non-corrosive.

6.2.9

Waste water treatment systems
The scope of this system includes the chemical wastewater collection and
treatment system.
The chemical wastewater collection and treatment system (chemical
drain) shall consist of sump- pumps for following areas








water treatment plant
chemical storage
chemical unloading station
floor drain at main machine sets
floor drain at boiler area
stack drain
battery room.
a complete piping system for chemical drain an intermediate storage basin
or tank sized to collect waste water out of above mentioned areas (
storage capacity shall be 24 h of station waste water production)
neutralization' and treatment tank for treatment of waste water with
agitator pH control and dosing units tn neutralize waste water with HCl
and NaOH dosing of FeCI3 and flocculent, settlement tank, sludge
treatment and nil necessary equipment for treatment, monitoring and
measuring or waste Water treatment including remote control devices,
piping and electrical equipment.
The wastewater output of the ion exchanger plant and Leakage from the
regeneration station shall be fed into the chemical drain system. In
addition any chemicals escaping from the indoor or outdoor chemical
preparation and storage plant in the event of leakages are also to be led
to the chemical drains.
The pre-treated chemical polluted wastewater shall be discharged to the ash pond.

All waste water discharge to the environment shall comply with the
Environmental Quality Standard of Bangladesh. Annex shows the relevant
standard values effluent. Additional equipment to comply with these
regulations shall be considered in the scope or supply and services.

6.2.10

Chlorination system
The scope of this system includes the chlorine feed system to chlorinate
the cooling water of Power Plant at the cooling water towers and to
chlorinate the potable water system. One (01) sodium hypochlorite (Naocl)
plant (free chlorine concentration shall be minimum 1%) having minimum
capacity 10 ton/ day shall have to be provided.

6.2.11 Laboratory
The laboratory
control of






installations

and

equipment

shall

be

installed

for

routine

service water
water-steam-condensate water
waste water and
coal and ash
oil
in a coal fired power plant.
The
scope
of
supply,
installation,
necessary supplies and services even
these.
The instruments
The
laboratory
stipulations.

and
shall

testing,
commissioning
comprises
if no special reference is made

all
to

equipment to be delivered shall be as up-to-date.
be
designed
in
accordance
with
general
safety

Analysis
The scope of supply,
necessary equipment to
power plant.

installation, testing, commissioning shall include all
analyse the parameters of a Coal fired thermal

Laboratory instruments
The
laboratory
equipment
shall
comprise
all
instruments
and
apparatus
necessary
for
the
analytical
investigations
including
all
necessary
accessories.
All
programmable
instrumental
computers
must
be
maintained
English
version
software.
Minimum
requirements
for
instruments and apparatus are as follows:___________________________________
Sl.
No

1

Name of instruments

Quantity

Remarks

01 (one) pc

Complete set with spare

2
3

Atomic Absorption
Spectrophotometer (AAS)
Spectrophotometer (Digital)
Spectrophotometer (Analog)

01 (one) pc
02 (two) pcs

4

pH meters (Digital)

03 (three) pcs

5

Electrical micro balance (Digital)

02 (two) pcs

6

03 (three) pcs

7

Electrical Conductivity meters
(Digital)
Electrical balances (Digital)

8

BOD meter (Digital)

02 (two) pcs

9

COD meter (Digital)

02 (two) pcs

Complete set with spare
Complete set with spare
for each
Complete set with spare
for each
Complete set with spare
for each
Complete set with spare
for each
Complete set with spare
for each
Complete set with spare
for each
Complete set with spare
for each

03 (three) pcs

Sl
.
N
1

0
1
1
1
2
1
3
1
4
1
5
1
6
1
7
1
8
1
9
2
02
12
22
32
42
52
6
2
27
82
93
0
3
31
23
3

Name of instruments

Quantity

Remarks

DO meter (Digital) ppb level.

02 (two) pcs

Oil Centrifuge machine (3000 rpm)

02 (two) pcs

Flash point testing device (Open cup)

02 (two) pcs

Flash point testing device (Closed
cu )
p
Di-electric constant tester for oil
analysis.
Electric Furnace with temperature
regulator
Electric Oven with temperature
control
Distillation apparatus (ASTM
method)
Ion selective meter (Digital)

02 (two) pcs

Pour pointer

02 (two) pcs

Electron Microscope
Contamic kit (for oil sediment test)
Decicator (big size)
Incubator
Autoclave
Computer (Inter Core two dual Core)
Temperature meter (for pump motor)

01(one) pc
01(one) pc
04 (four) pcs
01(one) pc
01(one) pc
01(one) pc
02 (two) pcs

Coal crusher (For laboratory analysis)
Coal disintegrator machine with sieve
Specific gravity meter (0.4 to 2.0)
Viscometer with oil temperate
regulator
Refrigerator (14 cft)
Electric heater
Colorimeter for free chlorine (Cl2)
test.

01(one) pc
01(one) pc
02 (two) pcs
02 (two) pcs

Complete set with spare
for each
100 pcs test tube (100ml
label marking) with
spares
Complete set with spare
for each
Complete set with spare
for each
Complete set with spare
for each
Complete set with spare
for each
Complete set with spare
for each
Complete set with spare
for each
Complete set with spare
for each
Complete set with spare
for each
Complete set with spare
Complete set with spare
Complete set with spare
Complete set with spare
Complete set with spare
Complete set with spare
Complete set with spare
for each
Complete set with spare
Complete set with spare
Complete set
Complete set with spare

01(one) pc
01(one) pc
02 (two) pcs

Complete set with spare
Complete set with spare
Complete set with spare

01(one) pc
02 (two) pcs
02 (two) pcs
02 (two) pcs
02 (two) pcs

Chemicals
The types and quantities of chemicals supplied shall he calculated in such
a
way
that
all
necessary
analyses
can
be
carried
out
to
permit
uninterrupted laboratory operation.
Normal solutions for titrimetric analysis to be
vials for later dilution (type; Merek Titricol or equivalent).

in

the

form

of

prefabricated

The
quantities
of
all
chemicals
must
be
sufficient
for
the
analytical
supervision
of
the
power
plant
during
commissioning
period,
warranty
period & LTSA period. The purity of the chemical substances must be in
accordance with the requirements of the various analytical methods to be
performed.

General glassware and tools
This scope of supply, installation, testing, commissioning comprises the
complete furnishing of the laboratory plastic/ glassware and safety kids.
Minimum requirements are as follows:_______________________________________

S
l.

Name of plastic/glass wares

Quantity

Each 05 (five) pcs.

Remarks

1

Automatic burette with pipes &
rubber ball
(1 ml, 2 ml, 3 ml, 10 ml, 25 ml)

2
3

Eye-protectors
Rubber thick hand gloves
(Acid/caustic proof)

50 (fifty) sets
50 (fifty) sets

Good quality
Good quality

4
5

Acid/caustic proof apron
Musk (Acid/caustic proof)

15 (fifteen) sets
25 (twenty five)
sets

Good quality
Good quality

6

Pyrex measuring glass cylinders
(500ml,250ml, 100ml, 50ml)

7

Pyrex glass beakers (1000ml,

05 (five) pcs +10
(ten) pcs +10 (ten)
pcs +10 (ten) pcs
Each 10 (ten) pcs.

500ml, 250ml, 100ml, 50m.)

Good quality, total
twenty five pcs.

Good quality , total
thirty five pcs.
Good quality , total
fifty pcs.

8

Pyrex glass funnels (5 ml, 10 ml,
20 ml, 25 ml, 50 ml)

Each 05 (five) pcs

Good quality, total
twenty five pcs.

9

Reagent glass bottles
(acid/caustic/silica proof) one liter

20 (twenty) pcs

Good quality, total
twenty pcs.

1
0

Reagent glass bottles (light
proof/coloured) one liter and half
liter

06 (six) pcs one
liter + 06 (six) pcs
half liter

Good quality, total
twelve pcs.

11

Pyrex glass volumetric flask
(1000ml, 500ml, 250ml, 100ml,
50ml)

Good quality, total
fifty pcs.

1
2

Plastic beaker (500 ml)

10 (ten) pcs + 10
(ten) pcs +10 (ten)
pcs +10 (ten) pcs
+10 (ten) pcs
05 (five) pcs.

1
3

Plastic type volumetric flask
(250ml, 100ml, 50ml)
Pipette filler

Each 10 (ten) pcs.

Good quality, total
thirty pcs.

1
4

Glass transparent
good quality

1
5

Conical flask with lid (250ml)

20 (twenty) pcs
different size
20 (twenty) pcs

1
6

Conical flask (250ml)

20 (twenty) pcs

Good quality,
twenty pcs.

1
7

Crucible (rectangular) ash test for
coal

20 (twenty) pcs

Good quality,
twenty pcs.

1
8

Crucible with lid (circular) volatile
test for coal

20 (twenty) pcs

Good quality,
twenty pcs.

1
9

Crucible with lid (circular) inner

20 (twenty) pcs

Good quality,
twenty pcs.

moisture test for coal

Good quality,
twenty pcs.
Good quality,
twenty pcs.

Laboratory furniture
The following laboratory
supplies as a minimum:





equipment

shall

be

included

in

the

scope

of



work places for wet-chemical work working surfaces proof against
chemicals and heat. doors and cabinets in the floor-mounted units with
integrated sinks at one end with a swivel-type mixing faucet for cold
and warm water and splash wall electrical connection outlets
compressed air supply gas supply and water supply



closed laboratory ventilation hood working surfaces proof against
chemicals and heat drawers and cabinets in the floor-mounted unit
electrical connections outlets compressed air supply. gas and water
supply

weighing table for the precision analysis balances


work benches with artificial resin surface for titrimetric analysis. proof
against chemicals and heat with drawers and cabinets in the floormounted units



potable water stainless steel connection from existing
distribution network to places where water is required .



complete compressed air distribution network in the laboratory rooms.
made of galvanised carbon steel piping from the compressed air
system



complete compressed air reducing and filtering device for oil-free and
dust-free

potable water

deminemlised water system
When furnishing the laboratory, there may he no gaps left in the working
surfaces. Adequate numbers or control elements for water, electricity,
compressed air supplies etc. shall he provided and so arranged that they
can be easily operated.
Adequate provision shall be made for storage space liter glass equipment
chemicals, etc. and likewise there shall he adequate working surfaces and
stowage surfaces for analysis equipment.
Spare parts.
Spare parts for the warranty period and LTSA period are to be included
in the price schedules.

6.3 Special Technical Requirements
The requirements specified in B0.6 under Section 'General Technical
Requirements are to apply and. where applicable. furtl;er regulations from
the other sections of this specification.

The water storage and treatment system shall afford:



fully automatic operation of single supply and treatment facilities
control from local control panels. Important alarms measurements and
status signals shall be transmitted to the Central Control Room.

6.3.1 Demineralised water treatment plant
The demineralised water treatment plant is to supply make-up water in
sufficient quantity for boiler feed-water and for the secondary cooling
water systems as well as for other consumers which require high-purity
water by demineralisation of raw water. Demineralising shall be done by
filtration, RO, decarbonizer and mixed bed exchangers. All common plant
items such as pumps. pipes controllers and resin traps are to be designed
so that the ion exchanger lines can work in parallel if necessary .
The dual media filter is to remove suspended matter from the raw water to
protect the ion exchangers from fouling by mechanical impurities.
The filters shall be designed for automatic backwash
backwash water shall be taken from the make-up water main.

cleaning.

The

Backwashing of the filter shall be started after triggering of a high
differential pressure alarm in the local control system of the water
treatment plant. The program for backwashing must be time controlled.
The dual media filter is to be provided with differential pressure gauge with
adjustable high alarm and 2 (two) sight-glasses.
Sampling facilities are to be provided at all requisite points upstream and
downstream of the filters.
Ion exchangers
The exchangers are to be protected internally against corrosion by a 3 mm
layer of tough rubber. All rubber lining is to be manufactured by the socalled hot process which means real vulcanization.
The cation and anion exchangers are to be equipped with two (2) sightglasses one (1) at the upper resin level one (I) in the upper section at the
exchanger vessel.
The above mentioned requirement applies for ion exchange vessels with a
now rate > 20 m 31h. Smaller plants could be constructed with GRP
vessels.
The mixed bed exchangers are to be equipped with three (3) sightglasses. one (1) at the upper resin level, one (1) in the upper section at
the exchanger vessel and one (1) at the level of the resin interface .

The exchanger resins selected must have a high resistance to fouling.
The number of nozzles in the exchangers shall be at least 80 per m .
The ion exchangers are to be equipped with a fully
enabling the regeneration cycle to be started and to run
in response to operation by the water treatment operator.

automatic system
fully automatically

The control system must provide the following programs:





Starting
Stopping
Selection of a particular step and
Repeat of each step of the program
The individual steps of the program e.g. backwashing, introduction of acid,
rinsing acid etc. must be indicated on the local control panel by means of
process graphic displays and specially designed control displays.
The program sequence shall stop at
operator
may
check,
for
example,
separated or mixed correctly.

predetermined points in order that the
that
the
mixed
bed
resins
have

The program must stop when regeneration has finished. The line, which
has been regenerated is to be brought back into operation by a control
action from the water treatment local control room.
The correct position and actual position of the various valves for each
stage of the program must be monitored automatically. In the event of a
fault, the program must stop and the fault indicated on the local control
panel. An alarm must also be given. if the operating programme is not
completed within a given time. Suitable precautions must be taken to
ensure that no switching errors can occur and no critical situation may
arise in the case of voltage or compressed air failures.
The
operation
or
the
demineralisation
plant
shall
be
controlled
by
continuously
measured
indicated
and
recorded
conductivity
readings
downstream of the anion and mixed bed exchangers.
Regeneration (end or the service cycle) of the mixed
be initiated based on first occurrence of anyone of the following:





bed

exchanger

shall

High conductivity in the effluent
High silica in the efl1uent
Pre-set volume or time has been reached
High differential pressure across the resin bed
Sampling facilities are to be
downstream of the ion exchangers.

provided

at

all

requisite

points

upstream

and

Special consideration has to be given to the corrosion protection of all
surfaces coming into contact with HCL .
Protective double block and bleed valving shall be installed where
necessary to prevent, contamination of the various media. as a minimum
at the following points:



Downstream of the regenerating pumps
in the regenerating pipelines before each mixed bed filter
The dilution
meters.

(regeneration)

water

lines

are

to

be

equipped

with

flow

Waste water, chemicals spilling and leakages
The wastewater output of the ion exchanger plant and leakage from the
regeneration station shall be fed into the chemical drain system. In
addition, any chemicals escaping from the indoor or outdoor chemical
preparation and storage plant in the event of leakages are also to be led
to the chemical drains.

6.3.2

Conditioning plants
The dosing units shall be fully skid-mounted units. The concentrated
chemicals ammonia and hydrazine supplied shall be diluted to a 1 to 2%
solution by mixing with demineralised water. The solid phosphate shall be
diluted to a 3 to 5% solution in a separate mixing and dosing station.
Dosing pumps shall be of the reciprocating metering type
Appropriate piping or adsorption devices
station shall ensure no ammonia gas leakage.

of

the

ammonia

conditioning

The dosing station for hydrazine shall be designed and erected in full
compliance with regulations for storage and handling of hazardous
substances.

6.3.3

Condensate treatment plant
The specified requirements for ion exchangers of demineralization plant
are to be applied also for the condensate treatment plant.
Regeneration (end of the service cycle) of the ion exchanger shall be
initiated based on first occurrence of anyone of the following:




High conductivity in the effluent
Pre-set volume or time has been reached
High differential pressure across the resin bed

The cartridge tilters are to be provided with differential pressure gaugewith
adjustable high alarm.

6.4 Technical Schedules
The
following
technical
schedules
comprise
part
of
this
specification. The data and requirements specified in the respective
forms are to adhered to and the missing data of forms are to be
completely tilled in. The completed technical schedules are to be
submitted with the Bid.
BPDB, Barapukuria Power Plant

Bidder/Contractor

B6: Water Storage and Treatment Systems
Technieal Data by Bidder

Unit

Cooling water system
Cooling water production capacity
Number of Settling water tank
Each Settling water tank capacity
Number of Clear water tank
Each Clear water tank capacity

m3 / hr
no.
m3
no.
m3

No. of other tanks (if required)
Capacity of other tanks, each

no.
m3

Number of coal slury tank
Each coal slury tank capacity

no.
m3

No. of clarifiers

no.

Capacity of each clarifier
Type of other filters

m3 / hr
-

No. of coal mine discharge water receiving pumps

no.

Capacity of each coal mine discharge water receiving
pump

m3 / hr

No. of Cooling water supply (makeup) pumps

no.

Capacity of each Cooling water supply (makeup) pump

m3 / hr

Potable water storage
Number of tanks
Net capacity

No.
m3

Material

Potable water pumps
Number of pumps
Rate of delivery

No.
m3/h

Power consumption at coupling

kW

Material: Housing/impeller

-

Chlorine dosing system potable water
Type of dosing equipment

Data

Chlorine dosing system cooling water system
Type of dosing equipment

BPDB, Barapukuria Power Plant

Bidder/Contractor

B6: Water Storage and Treatment Systems
Technical Data by Bidder

Unit

Data

Raw water storage (from existing deep tube well
water)
Number of tanks

No.

Net capacity

m3

Material

-

Raw water pumps
Number
of pumps
BPDB, Barapukuria
Power Plant

No.
Bidder/Contractor
m3/h

RateB6:
of delivery
Water Storage and Treatment Systems

Technical Data by Bidder

Unit

Power consumption at coupling

kW

Dual media filter

Material: Housing/impeller
Number of filters

Raw water pumps (other consumers)

No.

Throughput:
Minimum/Maximum
Number
of pumps

3
mNo.
/h

Material
Rate
of delivery
Diameter
Power consumption at coupling
Cyl. jacket length

m3/h
mm
kW
mm

Total height
Material:
Housing/impeller

mm

Number
of airstorage
blowers
Clear
water
Number
of
tanks
Rate of delivery

No.
N No.
m3 /h

Each
tank Net capacity
Degasifier

3
m
/h
No.

Material
Number of unils Throughput:

m3 /h

Number of pumps

No.

Demoralisation
water plant
Flow rale of pumps / Delivery head

3

m /h / bar

Number
Diameterofoflines
degasirier lower
Net continuous flow rate each line
Height
Net treated water volume per cycle each line
Material tower
Cycle length
Number of air blowers

No.
m3/h
mm
m3
mm
h

Regeneration
time
Rate of delivery

h
No.

Mixed bed exchanger
Regeneration
mode
Chemical consumption
Number of mixed bed exchangers

No.

HCI 100% each line
Throughput:•Minimum/Maximum

kg/cycle
m3/h

Exchanger
• NaOH
100%capacity:
each lineCation
Total
waste water discharged
Anion

eq
kg/cycle
m3/cycle
eq

capacity of cation resin
Quality of treatedOperating
water:
of anion resin
• Conductivity
• Silicamaterial quantity Cation
Exchanger
B6/FD-2

Anion

eq/IE
eq/IE
|jS/cm
mg/I
I
I

Velocity of operation flow (min.lmax.)
Velocity of backwash riow

m/h
m/h

Design pressure
Diameter

bar
mm

Cyl. jacket

mm

length Total
height

mm
mm

B6/FD-3

Data

BPDB, Barapukuria Power Plant

Bidder/Contractor

B6: Water Storage and Treatment Systems
Technical Data by Bidder
Ion exchange washing unit

Unit

Number of units
Volume tank

No.

Material:

I

Regeneration station for hydrochloric acid
Number of regeneration stations
Number of pumps

No.
No.

BPDB, Barapukuria Power Plant

Bidder/Contractor

Type
of pump
B6: Water
Storage and Treatment Systems
Rate of delivery

Technical Data by Bidder
Material

Data

I/h

Unit

Regenerationofstation
caustic
soda
Concentration
dilutedfor
acid
for regeneration
Volume of dosing tank
Number of regeneration stations

Data
%
I
No.

B6/FD-4

Number of pumps

No.

Type of pump
Rate of delivery
Material

I/h
-

Concentration of diluted acid for regeneration

%

Volume of dosing tank

I

Pump for. regeneration water
Number of pumps

No.

Rate of delivery

m3/h

Power consumption at coupling

kW

Material: Housing/impeller

-

Air blower
Number of blowers

No.
Nm3/h

Rate of delivery
Delivery head

Bar

Power consumption at coupling

kW

Pump for make-up water
Number of pumps

No.

Rate of delivery

m3/h

Power consumption at coupling'

kW

Material: Housing/impeller

-

Demineralised water storage tank
Number of tanks

No.

Each tank net capacity

m3

Diameter

mm

Cylindrical height

mm

Material:
B6/FD-5

BPDB, Barapukuria Power Plant

Bidder/Contractor

B6: Water Storage and Treatment Systems

Technical Data by Bidder

Unit

Data

Chemical handling

Hydrochloric acid system

Number of storage tanks

No.

Capacity

mJ

Diameter/cy!. height

mm

Material

Caustic soda system

Number of storage tanks

No.

Capacity

mJ

Diameter/cy!. height

mm

Material

Waste water treatment system

Sump pumps

Number of sump pumps

No.

Pumping rate

m3/h

Material

Intermediate storage basin/tank

Capacity

Material

Diameter/cy!. height or length/width/height

mm

Discharge pump

Number of pumps

No.

Pumping rate

m3/h

Power consumption at coupling.

kW

Malerial

Neutralisation tank
Number of tanks

No.

Capacity

mJ

Diameter/cy!. height
Material
Power consumption agitator

mm
-

kW

BPDB, Barapukuria Power Plant

Bidder/Contractor

B6: Water Storage and Treatment Systems
Technical Data by Bidder

Unit

Discharge pump

Number of pumps

No.

Pumping rate

m3/h

Power consumption at coupling

kW

Data

Material

Settling tank
Number of tanks

No.

Capacity

m'

Surface area

m2

Material

Sludge dewatering
Type of sludge dewatering
Conditioning station
Medium: Ammonia solution
Number of dosing stations

No.

Capacity of dosing tank

m'

Material: Tank

Number of dosing pumps

Agitator
Pipes, Valves

Pumping head

No.
bar

Pumping rate variable from - to

I/h

Material: Head/Piston / Diaphragm

Medium: Hydrazin
Number of dosing stations

No.

Number of dosing tanks

No.

Capacity of dosing tanks

m'

Material: Tank
Number of dosing pumps
Pumping rate variable from - to
Material: Head/Piston
B6/FD-7

Pipes, Valves

No.
l/h

BPDB, Barapukuria Power Plant

Bidder/Contractor

B6: Water Storage and Treatment Systems
Technical Data by Bidder

Unit

Medium: Trisodiumphosphate

Data

Number of dosing stations

No.

Number of dissolving tanks
Capacity of dissolving tanks

No.
m3

Material: Tank
Agitator
Number of transfer pumps

-

No
m3 /h

Rate of delivery
Material:
Number of lifting and tipping devices
Capacity of dosing lank

No.
m'

Material:' Tank
Number of dosing pumps

Pipes. Valves

Pumping rate variable from - to

No.
I /h

Material: Head/Piston

Medium: corrosion inhibitor

Diaphragm

Number of dosing stations

No.

Number of dissolving tanks
Capacity of dissolving tanks

No.
m3

Material: Tank
Agitator
Number of transfer pumps
Rate of delivery

No.
m3/h

Material:
Number of lifting and tipping devices

No.

Capacity of dosing tank

m3

Material: Tank

Number of dosing pumps

Pipes, Valves

No.

I/h

Pumping rate variable from - to
Material: Head/Piston
Diaphragm

BPDB, Barapukuria Power Plant

Bidder/Contractor

B6: Water Storage and Treatment Systems
Technical Data by Bidder
Condensate system

Unit

Data

Net treated water volume per cycle of each ion exchanger line

m3

Chemical consumption:
Regeneration time

h
h

Regeneration mode
Chemical consumption:
• HCI 100% each line
• NaOH 100% each line

kg/cycle
kg/cycle
m3/cycle

Total waste water discharged

Quality of treated water:
conductivity

|jS/cm

Cartridge filter
Number of filters

No.

Throughput:

m3/h

Material
Type and material of cartridge

Cation exchanger

Number of exchangers

No.

Throughput: Minimum/Maximum

m3/h

Exchanger capacity:
Exchanger material quantity

eq
l

Total exchange capacity max.

eq/lE

Velocity of operation flow (min./ max.)

m/h

Velocity of backwash flow

m/h

Design pressure

bar

Diameter

mm

Cyl. jacket length

mm

Total height

mm

Anion exchanger

Number of exchangers

No.

Throughput: Minimum/Maximum

m3/h

Exchanger capacity
Exchanger material quantity

eq

I

8PDB, 8arapukurla Power Plant

Bidder/Contractor

86: Water Storage and Treatment Systems
Technical Data by Bidder

Unit

Anion exchanger

Total exchange capacity max.

Data
eq/IE

Velocity of operation flow (min./ max.)

m/h

Velocity of backwash flow

m/h

Design pressure

bar

Diameter

mm

Cyl. jacket length

mm

Total height

mm

Regeneration station for hydrochloric acid
Number of regeneration stations

No.

Number of pumps

No.

Type of pump
Rate of delivery

I/h

Material

-

Concentration of diluted acid for regeneration
Volume of dosing tank

%

I

Regeneration station for caustic soda
Number of regeneration stations
Number of pumps

No.
No.

Type of pump
Rate of delivery

I/h

Material
Concentration of diluted acid for regeneration
Volume of dosing tank

%

l

Pump for regeneration water
Number of pumps

No.

Rate of delivery

m'/h

Power consumption at coupling
Material: Housing/impeller

kW
-

393



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