Pipeline Scada System

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Overview of Instrumentation, SCADA & Telecommunication Systems of Pipelines Anish Aggarwal GM(Project – Sys. & Gas) IndianOil Pipelines Division

Cross - country Pipelines
• For transportation of large volume of crude oil/ petroleum products from one place to another cross country pipelines are laid. • In comparison to other modes of transportation, pipelines are:
Most economical Safe Fast Environment friendly

Typical Cross-country Pipeline
A typical cross-country pipeline would have • An originating pump station (Mother station) • One or more intermediate stations – Booster/ Delivery station • RCPs (Repeater cum Cathodic Protection stations) in between • A terminal (delivery) station

Typical Cross-country Pipeline
For safe and reliable movement of products through cross-country pipelines, requirement of reliable control system & telecommunication system at each station as well as at the Master Control Station is essential to provide: • Efficient & safe operation of the pipeline • Remote monitoring and control of the pipeline • Inter station communication • Data transfer for SCADA and PAS

Instrumentation, SCADA & Telecommunication Systems
PAS SCADA-MCS

SCADA-SCC

PLC BASED CONTROL SYSTEM

FIELD INSTRUMENTATION

Indian Oil Pipelines

Indian Oil Pipelines

A Typical Pipeline Installation

A Typical Pipeline Installation

A Typical Pipeline Installation

Instrumentation Systems

Objectives for Safe Operations

A Well Designed Plant

Safety Systems

Viable + Eco friendly + Society Tolerable + Accident free Productive Operations

Purpose of Instrumentation in Pipeline
• Monitoring of process parameters: Pressure – Pressure transmitters & indicators Temperature – Temp. transmitters & indicators Flow – Flow meters e.g. turbine meters, PD meters, Ultrasonic flow meters Density- Density meters Level – Level transmitters, radar tank gauging systems

Contd….
• Protection of line pipe, tanks & Equipment: Pressure Switches Flow switches Level switches Oil mist detectors Efficient and smooth operation of pipeline • Leak detection

Safety Instrumentation Emergency Shutdown
• At each pipeline installation, an Emergency Shutdown System (ESD) is provided to ensure station / pipeline shutdown in case of emergency situations. • If the safety limits are exceeded, the control system automatically shuts down the pumping units and stations through emergency shutdown logics.

Safety Instrumentation Emergency Shutdown
In pipelines, Emergency Shutdown occurs primarily in case of any one of the following conditions:
• Actuation of any one of the emergency switches installed at different locations in the station including control room • Actuation through SCADA system • Sump tank level high-high • Station Discharge line pressure high-high • High-High Level Alarm of Storage Tanks • Suction header pressure low-low • Delivery line pressure high-high • Flow in surge line etc.

New Instruments ONLINE SULPHUR ANALYSER
• Euro IV compliant fuels having a sulphur content of 50 ppm would be introduced in select cities from Apr’ 2010. • The present method of cutting interface by measuring density of samples drawn from the pipeline cannot be used in case two similar grade of products differing only in sulphur content. • It is planned to install Sulphur analyzers for online monitoring of the sulphur content of the products and thereby helping in interface cutting of Euro – III & Euro-IV products.

Telecommunication Systems

Telecommunication Systems
For smooth operation of the pipeline, dedicated communication system with 99.9% (typ.) availability is installed for providing : • • • An instantaneous Reliable & Continuous exchange of voice & data between pumping/ terminal stations as well as with RCP locations.

Telecommunication Systems
Modes of communication in pipelines • • • • • • • H.F. Communication system V.H.F. Communication system Public leased circuits on hire Ultra high frequency (U.H.F) system Microwave Communication system Optical fiber Communication system Satellite Communication system

Telecommunication Systems
Communication Systems in pipelines• • Dual redundant hot standby STM-1 based systems. Equipped with Network Management System (NMS) at a central location for monitoring, control & configuration of communication equipment installed at different locations. • 12 Fibre Optical Fibre Cable

Telecommunication Equipments
FCBC 48V Battery Bank
Printer PC

D/I MUX

E P A B X

STM -1 Subscriber Lines

Conference Set

Data Connectivity for SCADA
CP UNIT RTU STM LINK DG SET SCADA SYSTEM

Telecommunication Systems Data Connectivity
• Apart from providing voice & SCADA data connectivity, the Ethernet Channels of communication network are utilised for:
Extending SAP Connectivity Extending LAN of Base Stations to other stations for e-mail services Remote viewing of CCTV Cameras Other applications e.g. connectivity to fire alarm system at RCP locations etc.

Control System

Control System
Enhanced Safety with :
• Highly reliable Dual redundant hot standby PLC based Control Systems having dual redundant power supplies, dual CPUs working on a dual redundant network. • Rugged and Reliable Remote Telemetry Units (RTUs) installed at Block Valve installations for monitoring the important parameters of mainline and control over these block valves through MCS/ SCCs.

Programmable Logic Controller (PLC)
• PLC provides regulating and discrete process control functions to the field units • Input/ Output modules of PLC are connected to basic primary sensors and also to final control element in the field • PLC is equipped with communication ports for communication with SCC and also to connect to LAPTOP to perform local station operations, programming and maintenance of the system

Contd….
• PLC provides PID loops • PLC control sequence software will continue to respond automatically to internal parameters as well as to field settings even in case of failure of communication with SCC maintaining safe operation of the station.

SCADA System

SCADA System
• SCADA system is installed to provide effective and efficient monitoring and control of the entire pipeline from Master Control Station (MCS). • SCADA system has a MCC and Station Control Centres (SCCs) at attended stations viz Pump Stations/ delivery station/ pump - cum - delivery stations/ terminal stations. • Programmable Logic Controllers (PLC)/ Remote Terminal Units (RTUs) are installed at attended stations/ scraper stations/ block valve stations for interfacing the field devices with the control system.

Typical SCADA System Schematic
MCS COMMUNICATION INTERFACE MIMIC

REMOTE SCC PLC BVs

REMOTE SCC PLC BVs

LOCAL SCC PLC BVs

REMOTE SCC PLC BVs

Main Objectives of SCADA System
The main objectives of a cross country petroleum pipeline SCADA system are: • To provide effective & efficient monitoring and control of entire pipeline network • To optimise use of equipment and manpower and to protect equipment. • To check pipeline integrity • Remote control of important station equipment, process set points & block valves from MCS

Contd….
• Emergency shutdown of entire pipeline from MCS • Acquisition & display of pipeline parameters, alarms from attended stations, scraper stations, C.P. stations & block valves at MCS

Master Control Station
MCS system is: • Designed to provide effective & efficient monitoring, safe operation and control of SCCs/ RTUs for entire pipeline • Configured with a dual hot standby computer system • Adopts distributed architecture using intelligent units; all interconnected thro’ a redundant local area network (LAN) • Equipped with software running under multiprogramming, multi-tasking real time environment

Contd….
• Includes self diagnostic facilities to check and indicate healthiness of the total system • Acquires data from SCCs/ RTUs in real time either through communication circuits • Displays/ records data dynamically in graphic and text formats for the entire pipeline • Archiving of data

Typical MCS Configuration
DUAL REDUNDANT CONTROL SYSTEM MCS cum SCC SERVERS REDUNDANT MCS OPERATOR WORKSTATIONS FOR DESPATCH PURPOSE SCC OPERATOR WORKSTATIONS ENGINEERING TERMINAL STATION-IN-CHARGE TERMINAL

DUAL REDUNDANT 100 MBPS ETHERNET LAN ROUTER’S GPS SYSTEM` ` DYNAMIC MIMIC FRONT END SERVER COLOUR DESKJET PRINTER TO SCC’s ON POINT TO POINT BASIS

LASERJET PRINTER

TO RTU’s

DOT MATRIX PRINTER

DUAL REDUNDANT PLC
I/O MODULES

FIELD DEVICES

FLOW FLOW COMPUTER- COMPUTER-2 1

DUAL I/O LAN

Station Control Centre (SCC)
SCC system is:
• Designed to provide effective & efficient monitoring, safe operation and control of local station and Scraper Station/ block valves, if any, under its control • Configured with a dual hot standby computer system • Adopts distributed architecture using intelligent units; all interconnected thro’ a redundant local area network (LAN) • Includes self diagnostic facilities to check and indicate healthiness of the total system

Contd….
• Acquires data from local PLC and Scraper Station/ block valves RTUs under its control in real time and transmits the same to MCS • Displays/ records data dynamically in graphic and text formats for the local station and block valves under its control • Archiving of data

Typical SCC Configuration
DUAL REDUNDANTCONTROL SYSTEM SERVERS DUAL REDUNDANT OPERATOR WORKSTATION STATION-IN-CHARGE TERMINAL

DUAL REDUNDANT 100 MBPS ETHERNET LAN

FRONT END SERVER

TO MCS

ROUTER COLOUR DESKJET PRINTER DUAL REDUNDANT PLC DOT MATRIX PRINTER

I/O LAN
TO RTU PROGRAMMING TERMINAL

I/O MODULES

FIELD DEVICES

FLOW COMPUTER

SCADA System
Alarm / Event Processing • Central processing of Alarms • Event list giving details of events of pipeline / control system • Facility of archiving events / alarms

SCADA System
Trend Generation • • • • • Real time and historical trends Number of trends on a single screen Facility of grid and precise reading On-demand trending Easy to configure

SCADA System
Reports • Daily / Shift reports • Automatic report printing facility • Export to different file formats for easy information exchange • Equipment availability reports • Management Information Reports

SCADA System
History • Logging of Alarms / events • Disk backup facility • Cyclic or on change logging • Triggered on timer / event / user action

MMI Screens

Pipeline Application Software
• Application software generates real time dynamic models as well as predictive/ trainer session models • Some of the typical dynamic models are
Leak Detection Batch tracking Scraper Tracking Pressure Drop Estimation Pipeline Performance Analysis

Pipeline Application Software
• Predictive/ trainer session models combine dynamic models and ‘hypothetical’ operations to analyse the outcome of Operator action in a safe and controlled manner. • Offline simulation models can also be used to train operators.

Pipeline Application Software
• Automatic Look Ahead Model
Uses “current state” from real time model and simulates future operation conditions of pipeline. Used to warn operator of impending short term violation of constraints etc.

• Predictive Model
It is an Off-line model. Uses same equation as Real Time Model and simulates pipeline operations based changes to the “current state” or archived historical states previously generated.

• Leak Detection (Pressure-Flow Deviation)
Detects occurrence of leak and gives estimate of volume, based on differences between the data produced from the Real Time Model and SCADA measurements.

Pipeline Application Software
• Leak Detection (Volume Balance)
Detects occurrence of a leak and gives estimate of volume based upon Mass/Volume Balance. Mass / Volume In = Mass / Volume Out : No Leak Mass / Volume In > Mass / Volume Out : Leak

• Batch Tracking
Batch tracking is done by tracking the movement of a known mass of the product in a pipeline. Time when a batch is introduced into the pipeline goes as basic input to the system. Depending upon the flow rate and density of the product at various points, the movement of product in the pipeline is calculated.

• Scraper Tracking
Scraper tracking model calculates the position of scrapers in the pipeline. It estimates the arrival time of each scraper at its receiving station. Used by the operator to monitor the movement of scrapers and to schedule scraper-receiving operations.

Pipeline Application Software Batch Tracking
Q D
Density Flow Rate Batch Dispatch time Batch/Interface volume Batch/Interface position Batch Arrival Time
Batch Tracking Module

Q D

Pipeline Application Software Scraper Tracking
Q Sig ID

Scraper Tracking Module

Q Sig

Scraper Launch Signal Flow Rate

Scraper Dispatch Time Scraper Position Scraper Arrival Time

Web Enabled SCADA System
• With the advancement of technology, Web Enabled SCADA systems are the recent trend in the industry. • Such a system gives access and control of a plant from anywhere in the world through the web. • The system picks up data from the operational SCADA system master stations or local control station by employing proxy servers and transports this data to web pages through a suitable communication medium.

Contd….
• On the web page, suitable interactive graphics are
created to give user friendly man machine interface for monitoring or control of a plant or pipeline.

• Can connect to multiple servers and multiple clients
inside the organization and at remote locations to monitor and control the system processes

• Tight security is enabled so that only authorized users
can control the process

Contd….
• Can send MIS report, maintenance report, breakdown
reports through auto emails

• Allows multiple simultaneous viewers in real time
worldwide

• Lowers cost by eliminating costly telephone and leased
line remote access

Contd….
• Due to increasing attack of the viruses through Internet,
special steps are required to be taken during design/ installation of Web Enabled SCADA systems to ensure that the system will not be damaged due to virus attacks.

• The security system installed as part of the Web Enabled
SCADA system needs to be monitored/ upgraded continuously as any damage to the control system due to virus attack may prove disastrous.

Contd….
• Fall back arrangements also need to be put in place as
part of original system and the same to be taken care of during design/ installation of the system.

Summing Up
• Accurate,
repeatable and reliable safety instruments and measurements are vital for efficient, more reliable, continuous & safe operation of pipelines. Technology (IT) have resulted Instrumentation & Process Control. in a great impact on

• The rapid and revolutionary changes in the field of Information

• It has always been our endeavor to continuously update the
Instrumentation, SCADA & Telecommunication System of our pipelines with latest state of the art technology.

Thank You

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