Fittings permit a change in direction of piping, a change in diameter of pipe or a branch to be made from the main run of pipe. They are formed from plate or pipe, machined from forged blanks, cast or molded from plastics. Fittings do not require normalizing in accordance with ASTM due to size or pressure rating. It should be normalized when used for service temperature below 30 °F.
Dimensional Standards
1) ASME/ANSI B 16.1 – Cast Iron pipe flanges and flanged fittings
2) ASME/ANSI B 16.3 - Malleable iron Threaded fittings
3) ASME/ANSI B 16.4 – Gray Iron Threaded fittings
4) ASME B 16.5 – Pipe Flanges and Flange fittings
5) ASME B 16.9 – Factory made wrought steel butt welding
6) ASME B 16.11 - Forged fittings, Socket welding and Threaded
7) ASME/ANSI B 16.28 – Wrought steel butt welding short radius elbows and return
8) ASME/ANSI B 16.42 – Ductile Iron pipe flanges and flanged fittings
9) BS 1640 – Butt weld fittings
10) BS 3799 – Socket weld and screwed end fittings
11) BS 2598 – Glass pipelines and fittings
12) IS 1239 Part II – M.S Fittings
13) IS 1538 – Cast Iron Fittings
14) MSS- SP – 43 – Stainless steel Fittings.
Advantages and disadvantages of Screws End fittings
- Easily made at site.
- Can be used where welding is not permitted due to fire hazard.
- Joints may leak when not properly sealed.
- Use not permitted by code if severe erosion, crevice corrosion, shock or vibration is anticipated.
- Strength of pipe and pipe fittings are reduced as threads reduce wall thickness.