ASME B31.3 – 2020 Process Piping

ASME has been defining piping safety since 1922.

ASME B31.3 contains requirements for piping typically found in petroleum refineries; chemical, pharmaceutical, textile, paper, semiconductor, and cryogenic plants; and related processing plants and terminals. It covers materials and components, design, fabrication, assembly, erection, examination, inspection, and testing of piping.

This Code applies to piping for all fluids including:

1. raw, intermediate, and finished chemicals;
2. petroleum products;
3. gas, steam, air and water;
4. fluidized solids;
5. refrigerants; and
6. cryogenic fluids.

Also included is piping that interconnects pieces or stages within a packaged equipment assembly.

Key changes to this revision include:

• Unlisted Valves (para. 307)
• Flexibility and Stress Intensification Factors (paras. 319 & 320)
• Impact Testing (paras. 323.2.2, 323.3.1)
• Flange Attachment Welds (para. 328.5.2)
• Heat Treatment (para. 330.1, 331.1)
• High Pressure Fluid Service Pressure Design (para. K302.3.2)
• High Pressure Fluid Service Fatigue Analysis (paras. K302.3, K304.8)

B31.3 is one of ASME’s most requested codes. It serves as a companion to ASME’s B31.1 Code on Power Piping as well as to the other codes in ASME’s B31 series. Together, they remain essential references for anyone engaged with piping.