Hello everyone (especially Richard Ay),

I am confused with the "Relief Load Synthesis" result which is the force of "thrust at valve pipe/vent pipe interface"&"thrust at vent pipe exit".

My input data are as follows: line tem. 500C,design pressure 7460Kpa,orivice ID 30mm,relief valve piping 96mm,vent stack length 6700mm, ratio of gas specific heats 1.3,gas constant 461.5 N.m./Kg./deg.K

I got the result which showed the interface force:9237N and the ventpipe exit force:4714N.

However, I check the result using the method of ASME B31.1 nonmandatory appendice II, which I got the F1 result:
5186N. This data is more nearly to the vent pipe exit force caculated by CAESAR II.
The input data of caculation by 31.1 is as the same as CAESAR II, which W = 12.4 lbm/sec (from caesar ii), A1=15.23in^2,h0=1463.37btu/lbm

How can I select for the piping stress caculation?

Thank first!