ASME VIII Div 1 App 2 vs API 6A

[MuzMond]

Hello,
Rookie engineer here.
I was asked to check an API 6A flange (15,000 psi) for excessive stresses using the ASME VIII Div 1 App 2 calculation, the stresses exceed the allowable when the flange dims match the API dims.

Is the ASME VIII flange calculations applicable to API 6A.

I will go through the standard again and look out for ommisions, just wondering if you more experienced guys could give me a heads up.

Regards,
Muz

 

[fegenbush]

Frequently, standard flanges fail an Appendix 2 check. I know that when I have done them, ASME B16.5 flanges are over bolted (too large of bolt diameter). If permissible, use the published pressure and temperature ratings. If that is not possible, it may be necessary to design a custom piece.