Design and installation of natural gas pipelines – Code of Practice: Part 3 Pre-commissioning and commissioning of pipelines
2006 Edition

Overview of Scope

• Encompasses pipeline systems used in petroleum, natural gas, and associated facilities.
• Incorporates references to international standards such as ISO 13623, ASME B31.8, API RP 1102, and API RP 1104 for comprehensive guidance.

Documentation Requirements (Clause 7.2)

• Mandates preparation of documents covering:
  • Health, Safety, and Environmental (HSE) policies
  • Quality Assurance (QA) frameworks
  • Quality Control (QC) measures

Definitions

• Adopts terminology as defined in IS 15663 Part 1.

Important Standards Referenced

Key Notes:

• Always use the most recent versions of referenced standards.
• Usage of symbols, dimensions, and grades as per BIS copyright is permitted for application.
• Comprehensive documentation covering HSE, QA, and QC is essential.

For specific formulas or tables related to design or testing, please specify the clause or topic needed.

Summary of Referenced Documents

• International standards referenced include:

  • ISO 13623: Pipeline transportation systems for petroleum and natural gas.
  • ASME B31.8: Standards for gas transmission and distribution.
  • API RP 1102: Steel pipeline crossings of railroads and highways.
  • API RP 1104: Pipeline welding practices.

• Documentation mandates (Clause 7.2):

  • Preparation of documents addressing HSE, QA, and QC requirements.

• Revision and Copyright:

  • Confirm usage of latest editions of referenced standards.
  • BIS copyright applies; reproduction requires permission except for implementation purposes.

• BIS Contact Information:

  • Head Office: Manak Bhavan, New Delhi.
  • Regional offices located in Kolkata, Chandigarh, Chennai, Mumbai, plus other branches nationwide.

Practical Guidance:

• Use referenced standards for detailed design, welding, and safety.
• Maintain updated documentation per Clause 7.2.
• Refer to IS 15663 Part 1 for detailed definitions.

flowchart LR
  A[IS 15663 Part 3] --> B[International Standards]
  B --> ISO13623[ISO 13623]
  B --> ASME_B31_8[ASME B31.8]
  B --> API_RP_1102[API RP 1102]
  B --> API_RP_1104[API RP 1104]
  A --> C[Documentation Clause 7.2]
  C --> HSE[Health, Safety & Environment]
  C --> QA_QC[Quality Assurance & Control]
  A --> D[BIS Offices & Contacts]

For design formulas or tables, consult the referenced standards as IS 15663 Part 3 mainly directs to these.

Terminology Guidance

• Definitions are adopted from IS 15663 Part 1; no new terms introduced here.
• For pipeline-related terms, consult IS 15663 Part 1.
• Aligns terminology with international standards such as ISO 13623, ASME B31.8, API RP 1102, and API RP 1104.

Covered Definitions Include:

• Pipeline transportation systems
• Welding and inspection vocabulary
• Quality assurance and control terms
• Health, safety, and environmental (HSE) concepts

Recommended Actions:

• Refer to IS 15663 Part 1 for comprehensive definitions.
• Cross-check terminology with international standards for consistency.
• Ensure documentation complies with Clause 7.2 covering HSE and QA/QC.

flowchart LR
  A[IS 15663 Part 3] --> B[Definitions]
  B --> C[Refer IS 15663 Part 1]
  C --> D[International Standards]
  D --> E[ISO 13623]
  D --> F[ASME B31.8]
  D --> G[API RP 1102]
  D --> H[API RP 1104]

Summary: Terminology is centralized in Part 1; consult it for all pipeline design and quality assurance terms.

Outline of Pre-commissioning Steps (Clause 5.2)

• Dewatering: Eliminate residual water inside the pipeline to prevent corrosion.
• Flushing and Dry Air Purging: Clean above-ground piping at stations such as dispatch, receiving, valves, pigging, and hook-up points.
• Swabbing: Remove moisture and debris using swabs propelled through the pipeline.
• Low-Pressure Leak Testing: Perform leak tests on above-ground piping sections using air.
• Documentation: Prepare comprehensive procedures and records for all pre-commissioning activities.

Important Parameters:

• Leak test pressure usually 1.1 times the design pressure or as project specifies.
• Flushing velocity maintained at a minimum (e.g., 1.5 m/s) to ensure debris removal.
• Use clean, dry air at slightly above atmospheric pressure for drying.

Pre-commissioning Process Flow

flowchart TD
  A[Begin Pre-commissioning] --> B[Dewatering]
  B --> C[Flushing & Dry Air Purging]
  C --> D[Swabbing]
  D --> E[Low Pressure Leak Test]
  E --> F[Documentation & Approval]
  F --> G[Pipeline Ready for Commissioning]

Refer Clause 6.2 for commissioning procedures following pre-commissioning.

Pre-commissioning Verification (Clause 5.2.1)

Before commissioning, confirm mechanical completion and system readiness through these checks:

• Pipeline Cover Inspection: Measure every 500 meters using tools like Pipe Current Measurement (PCM) to assess coating and cathodic protection.
• System Verification: Cross-verify all facilities against engineering drawings and specifications; record and rectify any deviations.
• Inspection of Field Instruments and Equipment: Check actuated valves, control valves, shutdown valves, transmitters, solenoid valves, alarms, meters, and gauges for proper operation.
• Pipeline Route Survey: Confirm installation of supports, cathodic protection, route markers, safety fencing, and protective barriers.
• Communication and Electrical Systems: Test communication channels, ensure uninterrupted power supply, measure earth resistance, and verify equipment complies with area classification.
• Instrumentation Controls and Interlocks: Validate that all control systems and interlocks function correctly.
• Utilities and Alarm Systems: Check availability and operability of power, UPS, water, air, and alarm systems.
• Safety Preparedness: Identify potential emergency scenarios and verify mitigation strategies.

Summary Table of Pre-commissioning Checks

Note: Document all checks as per Clause 7.1a. Subsequent commissioning includes leak testing and other procedures.

Key Points on Commissioning (Clause 6.2)

• Validates the pipeline system's readiness through integrity and functionality tests including pressure and leak checks.

• Preceding commissioning steps include cleaning, drying, and inspections as per Clause 5.2.

• Activities encompass residual dewatering, swabbing, magnetic cleaning, and low-pressure leak testing with dry air.

• Documentation must include records of all pre-commissioning steps, inertisation, and gas introduction.

Leak Test Pressure Formula

[ P_{test} = 1.5 , \times , P_{design} ]

Where:

• (P_{test}) is the test pressure
• (P_{design}) is the pipeline’s design pressure

Summary of Major Activities

flowchart TD
  A[Pre-commissioning] --> B[Residual Dewatering & Swabbing]
  B --> C[Magnetic Cleaning & EGP]
  C --> D[Low Pressure Leak Testing]
  D --> E[Inertisation]
  E --> F[Gas Introduction & Commissioning]

This sequence ensures pipeline integrity and operational readiness.

Essential Documentation as per Clause 7.1 & 7.2

• Records of all pre-commissioning checks.
• Evidence of residual dewatering and swabbing.
• Results of low-pressure leak tests on above-ground piping.
• Documentation of magnetic cleaning and electrochemical ground protection (EGP).
• Procedures and results of inertisation.
• Detailed records of gas-in and commissioning activities including pressurization, high-pressure leak testing, flow establishment, and a minimum 72-hour operational run.

Documentation must also address:

• Health, Safety, and Environmental (HSE) considerations.
• Quality Assurance (QA) and Quality Control (QC) plans.

Related International References

Summary Table of Documentation Components

flowchart TD
  A[Pre-commissioning Checks] --> B[Dewatering & Swabbing]
  B --> C[Low Pressure Leak Testing]
  C --> D[Magnetic Cleaning & EGP]
  D --> E[Inertisation]
  E --> F[Gas-in & Commissioning Activities]
  F --> G[High Pressure Leak Testing]
  G --> H[Flow Establishment & 72 Hr Run]

This flowchart depicts the documentation sequence required for commissioning compliance.