Steam Piping Union to Flange
Steam Piping Union to Flange
(OP)
I am looking to replace 3/4" and 1" schedule 80 and schedule 40, in both sizes, and wanted to know if there is a definite standard as to when you can and cannot use unions on certain size pipe. Steam pressure can range from 60 - 100 psi.





RE: Steam Piping Union to Flange
jt
RE: Steam Piping Union to Flange
- Socket-weld fittings (w/ SW unions for break-out) in all sizes 2" (DN 50) and smaller
- Butt-weld fittings (w/ Weld-neck Flanges for break-out) in all sizes 3" (DN 80) and larger.
RE: Steam Piping Union to Flange
The piping joints and size ranges are consistent with the power piping codes.
You ask:
"if there is a definite standard as to when you can and cannot use unions on certain size pipe"
Yes there is..... its in the ASME B31.1 and.3 codes and the defined list of acceptable standards for piping fittings and joints