Valve wall thickness
Valve wall thickness
(OP)
Hi,
Does anybody know of a definitive standard or method for calculating the thickness of a WOG rated ball valve? I have purchased ASME B16.34 which seems to only give class ratings and associated thicknesses, but it does not cover WOG.
I have a 1000 WOG valve with ANSI 150 flanged ends and wonder how it relates to ASME B16.34 or whether it is acceptable as a class 150 ball valve under the terms of ASME B16.34? It seems that the max. pressure (1000 psi per WOG rating) is higher than that of class 150.
Many thanks.
Does anybody know of a definitive standard or method for calculating the thickness of a WOG rated ball valve? I have purchased ASME B16.34 which seems to only give class ratings and associated thicknesses, but it does not cover WOG.
I have a 1000 WOG valve with ANSI 150 flanged ends and wonder how it relates to ASME B16.34 or whether it is acceptable as a class 150 ball valve under the terms of ASME B16.34? It seems that the max. pressure (1000 psi per WOG rating) is higher than that of class 150.
Many thanks.





RE: Valve wall thickness
You would need class 600 flanges on the valve in order to rate it 1000 psi WOG
RE: Valve wall thickness
If yes for first part, you are almost certainly stuck with ANSI 150.(Of practical reasons and cost for reconstructing and retesting.)
RE: Valve wall thickness
Thanks.
RE: Valve wall thickness
As soon as flanges are added, and the flanges are calimed to meet class 150, the valve rating cannot be higher than B16.34 allows for the material. Even the MSS standard (SP-72) for flanged ball valves state this. What may be happening is that an unknowledgeable valve supplier has modified their thread or socket weld end design to add flanges and continued to use the 1000 CWP rating designation. This is not correct.
RE: Valve wall thickness