1. Gas Transmission Pipelines
ENGINEERING SERVICES LP
HOUSTON, TEXAS
Engineering Specification

2. Gas Transmission Pipelines
1.0 SCOPE
Operation/Maintenance of Gas Transmission Piping Systems
Design
Fabrication
Installation
Inspection
Testing
Safety

3. Gas Transmission Pipelines
Intent
Provide engineering specifications for safe construction, opera-tion, maintenance, and inspection of gas transmission piping systems.
Shall meet or exceed ASME/ANSI B31.8 and DOT 49CFR192.

4. Gas Transmission Pipelines
Exclusions
Design and fabrication of pressure vessels covered by ASME BPV Code
Piping with metal temperatures above 450oF or below -20oF
Design and manufacture of proprietary items of equipment, apparatus, or instruments
Hazardous liquid pipelines (B31.4)

5. Gas Transmission Pipelines
3.0 PIPING SYSTEMS DEFINITIONS
General Terms
Piping Systems
Pressure Relief
Valves

6. Gas Transmission Pipelines
Piping Systems Component Definitions
Pipe and Piping Terms
Dimensional Terms
Mechanical Properties
Carbon Steel Pipe
Pipe Manufacturing Processes

7. Gas Transmission Pipelines
4.0 Design, Fabrication, Operation, and Testing Terms
LOCATION CLASS
Uprating
Pressure Terms
Temperature Terms
Stress Terms

8. Gas Transmission Pipelines
5.0 MATERIALS AND EQUIPMENT
Qualifications of Materials and Equipment
Marking
Material Specifications - Steel Pipe
Equipment Specifications
Transportation of Line Pipe
Conditions for the Reuse of Line Pipe

9. Gas Transmission Pipelines
6.0 WELDING
Welding Terms
Preparation for Welding
Butt Welds
Fillet Welds
Seal Welds

10. Gas Transmission Pipelines
Qualification of Procedures and Welders
Requirements for Piping Systems Operating at Hoop Stresses Less Than 20% SMYS
Requirements for Piping Systems Operating at Hoop Stresses More Than 20% SMYS
Variables Requiring Separate Qualification of Welding Procedures and Welders
Welder Requalification Requirements
Qualification Records

11. Gas Transmission Pipelines
Preheating and Stress Relieving
Preheating
Stress Relieving
Maximum carbon or carbon equivalent
Thickness
Dissimilar materials
Fillet and groove weld limitations
Stress Relieving Temperatures
Methods of Stress Relieving
Equipment for Local Stress Relieving

12. Gas Transmission Pipelines
Welding and Inspection Tests
Inspection of Welds on Piping Systems Intended to Operate at Less Than 20% SMYS
Inspection and Tests for Quality Control of Welds on Piping Systems Intended to Operate at 20% or more of SMYS
Repair or removal of defective welds in piping intended to operate at 20% or more of SMYS

13. Gas Transmission Pipelines
7.0 PIPING SYSTEM COMPONENTS AND FABRICATION DETAILS
Valves and pressure reducing devices
Flanges
Standard fittings
Branch connections
Special connections fabricated by welding
Closures

14. Gas Transmission Pipelines
Reinforcement of Welded Branch Connections
General requirements
Special requirements
Reinforcement of Multiple Openings
Extruded Outlets

15. Gas Transmission Pipelines
Expansion and Flexibility
Amount of expansion
Flexibility requirements
Combined Stress Calculations
Supports and Anchors for Above Ground Piping
Supports and Anchors for Buried Piping

16. Gas Transmission Pipelines
8.0 DESIGN, INSTALLATION, AND TESTING
Steel Pipe Design Formula
Limitations on Design Pressure, P
Limitations on Specified Minimum Yield Strength
Additional Requirements for Wall Thickness, t
Design Factors, F, and Location Classes
Fabricated Assemblies & Pipelines on Bridges
Cover, Clearance, and Casing Requirements

17. Gas Transmission Pipelines
Installation of Steel Pipelines
Construction Specifications
Inspection Provisions
Bends, Elbows, and Miters in Steel Pipelines
Pipe Surface Requirements for Pipe to Operate at 20% or more of SMYS
Detection and repair of gouges, grooves, dents, and arc burns

18. Gas Transmission Pipelines
Miscellaneous Construction Operations
Handling, hauling,and stringing pipe joints
Installation of pipe in the ditch
Backfilling
Preventing combusible gas-air mixture in the pipeline
Welding with gas in the pipeline
Purging of pipelines

19. Gas Transmission Pipelines
Testing After Pipeline Construction
Two (2) hour strength test at 1.5 times design pressure
Test pressures versus Location Classes
Leak testing after construction
Safety During Tests

20. Gas Transmission Pipelines
Compressor Station Equipment
Design
Electrical Facilities
Safety Devices
Pressure Limiting Devices
Explosion Prevention

21. Gas Transmission Pipelines
Compressor Station Piping
Gas Piping
Specifications for gas piping
Installation
Testing
Identification of valves and piping
Piping design codes - Fuel gas, air, lubricating oil, water, steam, and hydraulic.

22. Gas Transmission Pipelines
Control and Limiting of Gas Pressure
Requirements for Design of Pressure Relief and Pressure Limiting Stations
Capacity of Pressure Relieving and Pressure Limiting Stations and Devices
Required capacity
Proof of adequate capacity and satisfactory performance of pressure limiting and pressure relief devices
Uprating

23. Gas Transmission Pipelines
8.5 Valves
Required spacing of gas transmission pipeline valves
Location of gas transmission pipeline valves
Vaults (Valve Boxes)
Structural design requirements
Accessibility
Vault Sealing, Venting, and Ventilation
Drainage and Waterproofing

24. Gas Transmission Pipelines
9.0 OPERATING AND MAINTENANCE PROCEDURES
Basic Requirements
Essential Features of the Operating and Maintenance Plan
Essential Features of the Emergency Plan
Pipeline Failure Investigation
Prevention of Accidental Ignition
Blasting Effects

25. Gas Transmission Pipelines
9.2 PIPELINE MAINTENANCE
Continuing Surveillance of Pipelines
Pipeline Patrolling
Leak Surveys
Permanent Repair Procedures for Injurious Gouges, Grooves, Dents, Welding Defects, Leaks, and Nonleaking Corroded Areas
Testing Repairs and Replacement Pipe Sections

26. Gas Transmission Pipelines
PIPELINE MAINTENANCE (Continued)
Nondestructive Testing of Repairs, Gouges, Grooves, Dents, and Welds
Pipeline Leak Records
Pipeline Markers
Abandoning of Transmission Facilities
Repositioning a Pipeline in Service

27. Gas Transmission Pipelines
Miscellaneous Facilities Maintenance
Compressor Station Maintenance
Inspection and testing of relief valves
Repairs to compressor station piping
Maintenance of Pressure Limiting and Pressure Regulating Stations
Emergency valve inspection procedures
Valve records
Prevention of accidental operation

28. Gas Transmission Pipelines
Pipeline Service Conversions
Historical Records Study
Requirements for Conversion to Gas Service
Conversion Procedure
Records of the Conversion

29. Gas Transmission Pipelines
10.0 CORROSION CONTROL
External
Internal
Pipelines in High Temperature Service
Stress Corrosion and Other Phenomena
Records
Expanded corrosion control presentation is a part of three (3) other training programs.