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ASME B31.4 (Pipeline Transportation for Liquids and Slurries

ASME B31.4


Section B31.4 of the ASME Pressure Piping Code prescribes requirements for the design, materials, construction, assembly, inspection, and testing of piping transporting liquids such as crude oil, condensate, natural gasoline, natural gas liquids, liquefied petroleum gas, liquid alcohol, liquid anhydrous ammonia, and liquid petroleum products between producers’ lease facilities, tank farms, natural-gas processing plants, refineries, stations, ammonia plants, terminals, and other delivery and receiving points.

The scope of ASME B31.4 also includes the following:

  • Primary and associated auxiliary liquid petroleum and liquid anhydrous ammonia piping at pipeline terminals (marine, rail, and truck), tank farms, pump stations, pressure-reducing stations, and metering stations, including scraper traps, strainers, and prover loops

  • Storage and working tanks, including pipe-type storage fabricated from pipe and fittings, and piping interconnecting these facilities

  • Liquid petroleum and liquid anhydrous ammonia piping located on property which has been set aside for such piping within petroleum refinery, natural gasoline, gas processing, ammonia, and bulk plants

  • Those aspects of operation and maintenance of liquid pipeline systems relating to the safety and protection of the general public, operating company personnel, environment, property, and the piping systems

ASME B31.4 does not apply to:

  • Auxiliary piping such as water, air, steam, lubricating oil, gas, and fuel

  • Pressure vessels, heat exchangers, pumps, meters, and other such equipment, including internal piping and connections for piping except as limited by Paragraph423.2.4 (b) of ASME B31.4

  • Piping designed for internal pressures:

  1. At or below 15 psi (100 kPa) gauge pressure regardless of temperature

  2. Above 15 psi (100 kPa) gauge pressure if design temperature is below —20°F (—29°C) or above 250°F (120°C)

  • Casing, tubing, or pipe used in oil wells, wellhead assemblies, oil and gas separators, crude oil production tanks, other producing facilities, and pipelines interconnecting these facilities

  • Petroleum refinery, natural gasoline, gas processing, ammonia, and bulk plant piping, except as covered within the scope of the code

  • Gas transmission and distribution piping

  • The design and fabrication of proprietary items of equipment, apparatus, or instruments, except as limited by this code

  • Ammonia refrigeration piping systems provided for in ASME B31.5, Refrigeration Piping Code

  • Carbon dioxide gathering and field distribution systems

The rules of this code provide for protection of the general public and operating company personnel, for reasonable protection of the piping system against vandal- ism and accidental damage by others, and for reasonable protection of the environment.

Effective Edition, Addenda, and Code Cases

To determine the effective edition, addenda, and code cases for an application within the jurisdiction of ASME B31.4, follow the requirements delineated for ASME B31.1 for piping systems other than nuclear safety-related piping systems. #Little_PEng


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