ASME Dimensional Standards

To ensure compatibility of piping fittings manufactured by various manufacturers globally, American Society of Mechanical Engineers has devised dimensional standards for various piping fittings. These are the most used dimensional standards in word for piping. They cover various fittings like pipes, tees, elbows, reducers, flanges, crosses and many other fittings. Here is a comprehensive list of such piping dimensional standards.

Sr.NumberTitle
1B1.20.1Pipe Threads, General Purpose (Inch)
2B1.20.3Dryseal Pipe Threads (Inch)
3B16.1Cast Iron Pipe Flanges and Flanged Fittings: Classes 25, 125, and 250
4B16.3Malleable Iron Threaded Fittings: Classes 150 and 300
5B16.4Gray Iron Threaded Fittings: Classes 125 and 250
6B16.5Pipe Flanges and Flanged Fittings NPS 1/2 Through NPS 24 Metric/Inch Standard
7B16.9Factory-Made Wrought Buttwelding Fittings
8B16.10Face-to-Face and End-to-End Dimensions of Valves
9B16.11Forged Fittings, Socket-Welding and Threaded
10B16.12Cast Iron Threaded Drainage Fittings
11B16.14Ferrous Pipe Plugs, Bushings, and Locknuts With Pipe Threads
12B16.20Metallic Gaskets for Pipe Flanges: Ring-Joint, Spiral-Wound, and Jacketed
13B16.21Nonmetallic Flat Gaskets for Pipe Flanges
14B16.25Buttwelding Ends
15B16.28Wrought Steel Buttwelding Short Radius Elbows and Returns
16B16.34Valves : Flanged, Threaded, and Welding End
17B16.36Orifice Flanges
18B16.38Large Metallic Valves for Gas Distribution (Manually Operated, NPS 21/2 to 12, 125 psig Maximum)
19B16.39Malleable Iron Threaded Pipe Unions
20B16.42Ductile Iron Pipe Flanges and Flanged Fittings, Classes 150 and 300
21B16.47Large Diameter Steel Flanges (NPS 26 Through NPS 60)
22B16.48Steel Line Blanks
23B36.10Welded and Seamless Wrought Steel Pipe
24B36.19Stainless Steel Pipe