ASME B31.3
Process Piping
Summary
Covers piping typically found in petroleum refineries, chemical plants, pharmaceutical plants, textile plants, and cryogenic plants.
Scope
Design, materials, fabrication, assembly, erection, examination, inspection, and testing of piping.
Key Requirements
Examination Requirements
Chapter VI defines examination requirements.
- Normal service: VT + sampling NDT per Table 341.3.2
- Category M (lethal): 100% RT or UT of girth welds
- High Pressure: 100% RT or UT
Preheat Requirements
Table 330.1.1 defines minimum preheat based on P-Number, thickness, and carbon equivalent.
PWHT Requirements
Table 331.1.1 defines PWHT requirements.
- P-1 (carbon steel): required above 19mm
- P-4 (chrome-moly): typically required
- P-8 (austenitic SS): generally not required
Applicable Materials
Carbon SteelLow Alloy SteelStainless Steel 304Stainless Steel 316Chrome-Moly (P91)Chrome-Moly (P22)Duplex Stainless SteelNickel Alloys
Applicable Processes
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