Gas Transmission and Distribution Piping Systems

ASME Code for Pressure Piping, B31

AN INTERNA TIONAL PIPING C ODE ®

ASME B31.8-2016

(Revision of ASME B31.8-2014)

ASME B31.8-2016

(Revision of ASME B31.8-2014)

Gas Transmission and Distribution Piping Systems

ASME Code for Pressure Piping, B31

AN INTERNA TIONAL PIPING C ODE ®

Two Park Avenue • New York, NY • 10016 USA

Date of Issuance: October 19, 2016

The next edition of this Code is scheduled for publication in 2018. This Code will become effective 6 months after the Date of Issuance.

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CONTENTS

Foreword viii

Committee Roster x

Introduction xiv

Summary of Changes xvi

General Provisions and Definitions 1

801 General 1

802 Scope and Intent 1

803 Piping Systems Definitions 2

804 Piping Systems Component Definitions 4

805 Design, Fabrication, Operation, and Testing Terms and Definitions 7

832.5-1 Modulus of Elasticity for Carbon and Low Alloy

Steel 31

Figure

851.4.1-1 Allowable Ripple Heights 80

Tables

851.4.4-1 Wall Thickness for Unlikely Occurrence of

Burn-Through 81

854.1-1 Location Class 89

857.4-1 Wall Thickness Allowance for Uprating a Ductile Iron

High-Pressure Main or System 94

Chapter VI Corrosion Control 95

1. Corrosion Control — General 95

2. External Corrosion Control for Steel Pipelines 96

3. Cathodic Protection Criteria 98

4. Operation and Maintenance of Cathodic Protection

   Systems 98

5. Internal Corrosion Control 98

6. Steel Pipelines in Arctic Environments 99

7. Steel Pipelines in High-Temperature Service 100

8. Stress Corrosion and Other Phenomena 101

9. Cast Iron, Wrought Iron, Ductile Iron, and Other Metallic Pipelines 101

Chapter VII Intentionally Left Blank 102

Chapter VIII Offshore Gas Transmission 103

A800 Offshore Gas Transmission 103

A801 General 103

A802 Scope and Intent 103

A803 Offshore Gas Transmission Terms and Definitions 103

A811 Qualification of Materials and Equipment 104

A814 Material Specifications 105

A817 Conditions for the Reuse and Requalification of Pipe 105

A820 Welding Offshore Pipelines 105

A821 General 105

A823 Qualification of Procedures and Welders 105

A825 Stress Relieving 106

A826 Inspection of Welds 106

A830 Piping System Components and Fabrication Details 106

A831 Piping System Components 106

A832 Expansion and Flexibility 106

A834 Supports and Anchorage for Exposed Piping 107

A835 Anchorage for Buried Piping 107

A840 Design, Installation, and Testing 107

A841 Design Considerations 107

A842 Strength Considerations 108

A843 Compressor Stations 111

A844 On-Bottom Stability 112

A846 Valves 113

A847 Testing 113

A850 Operating and Maintenance Procedures Affecting the

Safety of Gas Transmission Facilities 114

A851 Pipeline Maintenance 115

A854 Location Class 115

A860 Corrosion Control of Offshore Pipelines 115

A861 External Corrosion Control 116

A862 Cathodic Protection Criteria 117

A864 Internal Corrosion Control 117