“Natural Gas Pipeline Overview” (ASME B31.8)

N. Bose BabuE.D (Projects and Technical Services)

Gujarat State Petronet Limited

05/02/2016

“The greatest discovery of my generation is that a human being can alter his life by altering his attitudes of mind” - William James

“Natural Gas Pipeline System Overview”

What is a Standard ?

A standard can be defined as a set of technical definitions and guidelines –“how to” instructions for designers and manufacturers.

Standards, which can run from a few paragraphs to hundreds of pages, are written by experts who sit on many committees.

What is a Code ?

A code is a standard that has been adopted by one or more government bodies and that has the force of law.

B31.8 and 49 CFR 192 or PNGRB Regulations.

• ASME B31.8 and 49CFR192 (Part 192) are separate, independent documents developed and maintained by separate organizations.

• B31.8 is an engineering safety standard, written in performance language.

• Part 192 is a minimum safety regulation, written in prescriptive language.

• The provisions of PNGRB Regulations (808) E, is binding in India for all Natural Gas Pipeline Projects.

• The code is not a handbook

• Pipeline design principals are qualitative

• Pipeline failures occur at defects and discontinuities

• Material toughness is important

• Safe operation requires sound maintenance practices

MILESTONES IN PIPELINE HISTORY

• ca. 1800 Gas mains in streets of London and Baltimore

• 1858-9 Oil and gas lines laid from Col. Drake’s wells

• ca. 1900 Earliest era of pipelines still in operation today

• 1928 1st Ed. of API 5L

• 1935 1st Ed. of ASA B31.1 Code for Pressure Piping, Tentative Standard

• 1952 First publication of B31.1.8 as separate volume of B31 Code for Pressure Piping

• 1955 First publication of B31.1.8 under new Section 8 Committee

• 1968 49CFR192 promulgated; essentially copied from 1968 edition of B31.8

• 1970 B31.8 Section Committee became dormant

• 1974 B31.8 committee reformed to advance state of recommended practices

ASME PIPING CODES

• B31.1 Power Piping

• B31.2 Fuel Gas Piping

• B31.3 Process Piping

• B31.4 Pipeline Transportation Systems for Liquid Hydrocarbons and Other Liquids

• B31.5 Refrigeration Piping

• B31.8 Gas Transmission and Distribution Piping Systems

• B31.9 Building Services Piping

• B31.11 Slurry Transportation Piping Systems

• BPV III, NB/NC/ND-3600 Nuclear Power Piping

Types of Codes

EMPIRICAL

Based on EXPERIENCE

(Design by RULES)

• All B31 piping codes

• BPV I unfired boilers

• BPV III - Class 2/3

• BPV VIII - Div 1

ANALYTICAL

Based on THEORY

(Design by ANALYSIS)

• BPV III - Class 1 nuclear

• BPV VIII - Div 2

Back of Title Sheet

CODE OPERATIONS

• The B31 Main Committee operate under written procedures accredited by ANSI and which require:

• A balanced membership

• Memberships to be individual, not corporate

• A consensus to revise the Code and issue Interpretations

• Public review of proposed revisions to the Code

Further:

• ASME does not approve or rate any item, construction, or activity

• Participation by government or industry representatives does not constitute government or industry endorsement of the Code or ASME endorsement of represented organizations

B31.8 INTERPRETATION EXAMPLE

INTERPRETATION: 6-5

SUBJECT: Allowable Stress for Buried Pipe Subject to Ground Movement

DATE ISSUED: August 21, 1989

APPLICABLE EDITION: [Now required by B31]

INQUIRY: What is the maximum allowable stress for buried pipelines subject to movement at active ground faults?

REPLY: B31.8 does not provide a maximum allowable stress for catastrophic events such as earthquake fault movement, see Para. 840(a).

CODE CASE 137PIPING NOT COVERED BY ANY B31 CODE SECTION

Inquiry: When no B31 Section of the Code for Pressure Piping specifically covers a piping system, which Section should be used for materials, design, fabrication, assembly, erection, examination, inspection, and testing of the system?

Reply: At his discretion, the user may select any Section determined to be generally applicable. However, it is cautioned that supplementary requirements to the Section chosen may be necessary to provide for a safe piping system for the intended application. Technical limitations, legal requirements, and applicability of other codes or standards are other factors which should be considered.

NEED FOR ENGINEERING JUDGEMENTINTRODUCTION

The Code sets forth engineering requirements deemed necessary for safe design and construction of pressure piping. While safety is the basic consideration, this factor alone will not necessarily govern the final specifications of any piping system. The designer is cautioned that the Code is not a design handbook; it does not do away with the need for the designer or for competent engineering judgment.

NEED FOR ENGINEERING JUDGEMENT802.21 INTENT

The requirements of this Code are adequate for safety under conditions usually encountered in the gas industry.Requirements for all unusual conditions cannot be specifically provided for, nor are all details of engineering and construction prescribed. Therefore, activities involving design, construction, operation, or maintenance should be undertaken using supervisory personnel having knowledge to make adequate provision for such unusual conditions and specific engineering and construction details. All work performed within the scope of this Code shall meet or exceed the safety standards expressed or implied herein.

803 DEFINITIONS

• Pipeline or transmission line: pipe installed for purpose of transmitting gas from one location to another or to interconnect sources of supply

• Gas main or distribution line: pipe installed in a community to convey gas to individual service lines

• Service line: piping installed between main and meter

• Gathering line: pipe which transports gas from production to a gas processing plant

CODE LANGUAGE

• Shall = provision is required

• Should = provision is recommended but not required

• May = provision is not required and not prohibited (optional)