ASME piping standards
American Society of Mechanical Engineers (USA): Codes for piping design, pressure vessels and dimensional standards for flanges, fittings, valves and threads. 27 standards most used in piping, flanges, fittings, valves and materials.
| Standard | Covers | Category | On this site |
|---|---|---|---|
| ASME B1.20.1 | NPT taper pipe threads, general purpose (inch) | Threads | Open → |
| ASME B16.1 | Grey iron pipe flanges and flanged fittings | Flanges | Open → |
| ASME B16.5 | Pipe flanges and flanged fittings NPS ½ to 24, Class 150–2500 | Flanges | Open → |
| ASME B16.9 | Factory-made wrought buttwelding fittings | Fittings | Open → |
| ASME B16.10 | Face-to-face and end-to-end dimensions of valves | Valves | – |
| ASME B16.11 | Forged fittings, socket-welding and threaded | Fittings | Open → |
| ASME B16.20 | Metallic gaskets for pipe flanges (ring joint, spiral wound, jacketed) | Gaskets | Open → |
| ASME B16.21 | Non-metallic flat gaskets for pipe flanges | Gaskets | – |
| ASME B16.25 | Buttwelding end preparation (bevels) | Fittings | Open → |
| ASME B16.34 | Valves — flanged, threaded and welding end; pressure–temperature ratings | Valves | – |
| ASME B16.36 | Orifice flanges | Flanges | Open → |
| ASME B16.47 | Large-diameter steel flanges NPS 26 to 60, Series A and B | Flanges | Open → |
| ASME B16.48 | Line blanks (spectacle blinds, spacers, paddle blanks) | Flanges | Open → |
| ASME B18.2.1 | Inch-series bolts and screws (hex, heavy hex) | Bolting | Open → |
| ASME B18.2.2 | Inch-series nuts (hex, heavy hex) | Bolting | Open → |
| ASME B31.1 | Power piping code | Design codes | – |
| ASME B31.3 | Process piping code | Design codes | Open → |
| ASME B31.4 | Pipeline transportation systems for liquids and slurries | Design codes | – |
| ASME B31.8 | Gas transmission and distribution piping systems | Design codes | – |
| ASME B31.9 | Building services piping | Design codes | – |
| ASME B36.10M | Welded and seamless wrought steel pipe dimensions | Pipe | Open → |
| ASME B36.19M | Stainless steel pipe dimensions (S schedules) | Pipe | Open → |
| ASME BPVC Section I | Rules for construction of power boilers | Design codes | – |
| ASME BPVC Section II | Materials — specifications (SA, SB) and allowable stresses | Materials | Open → |
| ASME BPVC Section V | Non-destructive examination | Testing & inspection | – |
| ASME BPVC Section VIII Div. 1 | Rules for construction of pressure vessels | Design codes | – |
| ASME BPVC Section IX | Welding, brazing and fusing qualifications (WPS, PQR, WPQ) | Welding | – |
Subjects are short summaries, not official titles. Always buy the current edition from the issuing body; check which edition your project specification names.
Frequently asked questions
Which ASME standards cover piping?
ASME B1.20.1 (npt taper pipe threads); ASME B16.1 (grey iron pipe flanges and flanged fittings); ASME B16.5 (pipe flanges and flanged fittings nps ½ to 24); ASME B16.9 (factory-made wrought buttwelding fittings); ASME B16.10 (face-to-face and end-to-end dimensions of valves); ASME B16.11 (forged fittings) and others listed on this page.
Last updated 2026-11-02