Managing System Integrity of Gas Pipelines Jegadeesh Nagaraj - - PDF document

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Managing System Integrity of Gas Pipelines

14th March, 2018 at CIDM Jegadeesh Nagaraj Manager (O &M), GSPL

GSPL was set up in 1998 to complement the efforts of GSPC. While GSPC harnesses and procures natural gas, GSPL is building the infrastructure that transmits the gas across the state of Gujarat and ultimately allows last-mile linkage to the end-user. GSPL is laying a gas grid, to facilitate gas transmission from supply points to demand centers. Equipped with the latest bi-directional gas transmission technology to enable two-way gas flow. The network is continuously monitored using SCADA systems integrated with GIS technology. GSPL is India’s second largest natural gas transmission company by network length

• perating 2618 kms in Gujarat. First company to start services on common carrier

principle. Connected to all major sources like Petronet LNG Dahej, Shell LNG Hazira, Cairn , Panna-Mukta-Tapti (PMT), Reliance KG Basin with RGTIL’s East-West Pipeline, ONGC - same is being delivered to 23 districts in the State.

ABOUT GUJARAT STATE PETRONET LTD

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Natural Gas Pipeline System

• Designed for High Pressure Natural Gas Transmission
• Buried(Under ground), Highly Safe for bulk transmission,

Reliable Network

• Every 20~25 Kms

Emergency Isolation and Remote Operation

• Master Control Room

Monitoring all technical parameters through SCADA 24X7

• Cathodic Protection to prevent corrosion for under

ground pipeline

• Connecting Gas Source to Demand Centers

Pipeline

• Prevention of Pipeline failure through Integrity

Management System

What happens when disaster strikes…

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WHAT IS INTEGRITY

• The quality of being honest and having strong moral
• principles. Doing the right thing even when nobody's
• looking. your moral or ethical convictions.

Persons having integrity means you are true to yourself and would do nothing that demeans

• r dishonours you.

FOR PROCESS – integrity means doing the right thing in a right time and reliable way INTEGRITY

What is Integrity Management System ? “A comprehensive, systematic and integrated process that includes all the activities that are required to prevent a failure”

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Background of Integrity Management System

Contd..

• PNGRB (Integrity Management System for Natural Gas

Pipelines) Regulation, 2012 notified No: F. No. Infra / IM/NGPL /1/2010 dated 05/11/2012.

• ASME B31.8S (Managing System Integrity of Gas Pipelines).

Supplement for ASME 31.8

• NACE RP – 0102 In-Line Inspection of Pipelines
• NACE RP – 0502 External Corrosion Direct Assessment
• NACE SP – 0206 Pipeline Internal Corrosion Direct

Assessment Methodology Regulation- India Standards (Non-mandatory)

Integrity Management System

Contd..

a life cycle approach….

It involves all aspects of the Pipeline system right from Design, Construction, Operation & Maintenance (O&M) and Integrity Management.

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• Identifying potential pipeline impact by threat
• Gathering, reviewing and integrating data
• Risk assessment
• Evaluate all threats
• Integrity assessment
• Response to integrity assessment and mitigation

Pipeline Integrity Management System

19-03-2018 7 Integrity Management Program Integrity Management Program Elements (IMP)

IMP elements IMP Plan Performance Plan Communication Plan Management of Change Plan Quality control plan

IMP - Process Flow Diagram

• !

! ! !

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Integrity Management Program

What Can a Risk Assessment Do??

“A risk assessment, no matter what method, it cannot be precise because risk is not a precise concept.”

Risk Identification

Contd..

• RISK = Probability (degree of belief) * Consequences
• Any Pipeline segment the Risk Identification is a MUST
• The Risk can be categorized into three levels:

– Low – Medium – High

“A Systematic process in which potential hazards from facility

• peration are identified, and the likelihood and consequences of

potential adverse events are estimated”

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Integrity Management

Contd..

PIPELINE THREATS

Integrity Management

22 Threats (for 1threat, cause-unkown) 21 threats are divided in 9 Categories and grouped in 3 time factors

Contd..

Pipeline Threats (ASME31.8S)

I.Time Dependent 1)External Corrosion (EC) 2) Internal Corrosion (IC) 3) Stress Corrosion Cracking (SCC) II) Stable 4) Manufacturing related threats

• Defective pipe seam welds
• Defective Pipe (Lamination, Hard Spots)

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Contd..

Construction 5) Construction/Welding/Fabrication Threats

• Defective Pipe Girth Weld
• Defective Fabrication Weld
• Wrinkle Bend
• Stripped Threads/Broken Pipe/ Coupling failure

6) Equipment

• Gasket, O-ring Failure
• Control/Relief Valve Failure
• Seal /Pump packing failure
• Miscellaneous

Integrity Management

Pipeline Threats

III) Time Independent 7) Third Party / Mechanical Damage * Damage inflicted by 1st, 2nd, 3rd Parties * Previously Damaged Pipe * Vandalism or Terrorism 8) Incorrect Operation *Incorrect Operational Procedure 9) Weather Related & Outside Force * Cold Weather * Lightning * Heavy Rains or Floods * Earth Movements

Integrity Management

Pipeline Threats

19-03-2018 11 Pipeline Threats- Assessment Techniques

Contd..

Threats Assessment Methods Internal /External Corrosion In-line inspections / Geometry/ Gauging inspections Cathodic Protection evaluation - PSP PSP ON/OFF Survey CIPL / DCVG, CAT Survey Peel off Test Soil Resistivity assessment Third Party Damage ROU/ROW details Location Class, Crossings, HCA, PDI Patrolling records Identification of High Consequence Areas Equipment/ Operation Errors Pipeline monitoring -Pressure,Temp.,Flowrate,Flow Velocity, Quality In-line inspections / Geometry/ Gauging inspections Pipe Thickness records Equipment breakdown records Gas leakage/ Failure records Subsurface gas detection survey Depth /Dig Verification Survey Under ground pipe DC Power

Coating Damage

Series of Anodes (auxiliary structure)

+

• Underground

Above ground Soil

T/R Unit

Coating

BASIC CP INSTALLATION & ITS WORKING

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Contd..

• In-line inspections / Geometry/ Gauging

inspections Video Clip

• Coating integrity survey (CIPL / DCVG & CAT

Survey)

• Stress corrosion cracking study Video clip
• Corrosion Coupons
• Regular aerial & Foot patrolling
• Cathodic Protection monitoring

It is very important to have a good pipeline design, well supervised construction and professionally managed Operation & Maintenance to have a better results of IMP

Contd..

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• THANK YOU