I'm checking the stress analysis of a 12" stainless steel pipe, but I can´t find the allowable stress in the B31.3 code ( material ASTM 778 Gr. TP 316L)
ASTM 778 Gr. TP 316L is not listed in B31.3 so you have to look at B31.3 paragraph 323.1.2 and then paragraph 302.3 for allowable stress bases. You might be interested in this web site: