Piping Codes, Standards, and Specifications

In the new computer-aided design (CAD) era, the compliance to industry codes, standards, and specifications remains essential for the successful completion of a process facility, safe operation, and the satisfaction of health, safety, and environmental (HSE) requirements. The chapter is divided into the following sections:

1.1 Introduction

1.2 Definitions

1.3 Codes

1.4 Standards and Specifications

1.1 Introduction

Compliance to a code generally is mandatory, imposed by regulatory and enforcement agencies or their representatives. Also, the insurance company for the facility requires the owner to comply with the requirements of the relevant code or codes to ensure the safety of the workers and the general public. Compliance to standards normally is required by the rules of the applicable code or the purchaser's specification.

A vast majority of these codes, standards, and specifications have their origins in the United States, because initially this is where the most oil and gas activity was based. This is not likely to change in the near future; however, in recent years, there has been an increase in the alignment with ISO, and this is likely to increase.

Despite the strength of U.S. codes, standards, and specifications, similar documents from other engineering centers should not be ignored, like British standards (UK), DIN (Germany), AFNOR (France), JIS (Japan), and others.

1.2 Definitions

A code identifies the general requirements for the design, materials, fabrication, erection, test, and inspection of process piping systems. For example, ASME B31.3-Process Piping is classified as a design code. This is the most commonly used international design code for process plants.

A standard contains more-detailed design and construction parameters and standard dimensional and tolerance requirements for individual piping components, such as various types of valves, pipe, tee, flanges, and other in-line items to complete a piping system. For example, ASME B16.5, Pipe Flanges and Flanged Fittings, is classified as a dimensional standard, but it also references ASTM material specifications.

A specification, as the word implies, gives more specific information and data on the component; and ASTM's are considered to be material specifications, although they sometimes are ambiguously called standard specifications. ASTM A105 is the "standard specification for carbon steel forgings for piping applications."

To conclude and combine these definitions, ASME B31.3 is a design code, with flanges designed to the ASME B16.5 standard, which are constructed to the material specification ASTM A105.

It is not uncommon for even experienced personnel to get the definitions of these three types of document mixed up, and it is important to comprehend the distinct differences.

1.3 Codes

A regulatory organization imposes mandatory compliance to a code, from the basic design through to mechanical completion and eventual hand-over of a plant to the operator. For example, ASME B31. 3, Process Piping, is the refinery code. The insurer of the plant will make this a contractual requirement to ensure safety for personnel and plant during construction, commissioning, and ongoing operation.

The codes, standards, and specifications that relate to piping systems and piping components are published by various organizations. These organizations have committees comprising representatives from industry associations, manufacturers, EPC contractors, end users/operators, government bodies, insurance companies, and other interested groups.

A committee is responsible for maintaining, updating, and revising the codes, standards, and specifications, taking into consideration all technological developments, research, experience feedback from end users, and any changes in referenced codes, standards, specifications, or regulations.

The oil and gas industry has been established for many years, and changes to industry codes are generally negligible. Periodically, revisions are published, listing amendments that have been made to the document. It is essential that engineers and designers who work regularly with the document use the latest edition.

With regard to referencing a particular edition, issue, addendum, or revision of a code or standard, the piping engineer must be aware of the national, state, provincial, and local laws and regulations governing its interpretation in addition to the commitments made by the owner and the limitations delineated in the code or standard.

1.3.1 American Society of Mechanical Engineers Boiler Pressure Vessel Codes

The boiler pressure vessel (BPV) section covers major codes and standards related to piping. Some of these codes and standards are discussed briefly, whereas others are listed for convenience of reference.

American Society of Mechanical Engineers

The American Society of Mechanical Engineers (ASME) is one of the leading engineering organizations in the world. It develops and publishes engineering codes and standards. The ASME established a committee in 1911 to formulate rules for the construction of steam boilers and other pressure vessels. This committee, now known as the ASME Boiler and Pressure Vessel Committee, is responsible for the ASME boiler and pressure vessel code. In addition, the ASME has established committees that develop many other codes and standards, such as the ASME B31 code for pressure piping.

ASME Boiler and Pressure Vessel Code

The ASME Boiler and Pressure Vessel Code comprises 12 sections:

Section I, Power Boilers.

Section II, Material Specifications.

Section III, Rules for Construction of Nuclear Power Plant Components.

 Division 1, Nuclear Power Plant Components.

 Division 2, Concrete Reactor Vessel and Containments.

 Division 3, Containment Systems and Transport Packaging for Spent Nuclear Fuel and High-Level Radioactive Waste.

Section IV, Heating Boilers.

Section V, Nondestructive Examination.

Section VI, Recommended Rules for Care and Operation of Heating Boilers.

Section VII, Recommended Rules for Care of Power Boilers.

Section VIII, Pressure Vessels.

 Division 1, Pressure Vessels.

 Division 2, Pressure Vessels (Alternative Rules).

 Division 3, Alternative Rules for Construction of High-Pressure Vessels.

Section IX, Welding and Brazing Qualifications.

Section X, Fiber-Reinforced Plastic Pressure Vessels.

Section XI, Rules for In-Service Inspection of Nuclear Power Plant Components.

Section XII, Rules for Construction and Continued Service of Transport Tanks.

Code Cases: Boilers and Pressure Vessels.

Code Cases: Nuclear Components.

ASME Section I, Power Boilers

This ASME section provides requirements for all methods of construction of power, electric, and miniature boilers; high-temperature water boilers used in stationary service; and power boilers used in locomotive, portable, and traction service. Rules pertaining to use of the V, A, M, PP, S, and E code symbol stamps are included. The rules are applicable to boilers in which steam or other vapor is generated at pressures exceeding 15 psig and high-temperature water boilers intended for operation at pressures exceeding 160 psig or temperatures exceeding 250°F. Superheaters, economizers, and other pressure parts connected directly to the boiler without intervening valves are considered part of the scope of Section I.

ASME Section II, Material Specifications (Scope)

ASME Section II consists of four parts, three of which contain material specifications and the fourth the properties of materials listed previously.

Part A, Ferrous Material Specifications.

Part B, Nonferrous Material Specifications.

Part C, Specifications for Welding Rods, Electrodes, and Filler Metals.

Part D, Properties

Practical Guide to ASME Section II.

Part A, Ferrous Material Specifications, provides material specifications for ferrous materials adequate for safety in the field of pressure equipment. These specifications contain requirements and mechanical properties, test specimens, and methods of testing. They are designated by SA numbers and are derived from ASTM A specifications.

Part B, Nonferrous Material Specifications, provides material specifications for nonferrous materials adequate for safety in the field of...