I am working on a manifold design (design pressure 15000 psi) which is based on ASME B31.3 Chapter IX High Pressure Piping. Unlike B31.4 & B31.8 there is no separate code for B31.3 high pressure piping in CAESAR.

Based on B31.3 code the allowable stresses in CAESAR are based on tables in Appendix A. But Chapter IX K302.3.2 recommends a different method using Appendix K values to calculate the allowable stresses.

If we compare allowable stress value (27.3 ksi) Appendix A value for X70 material with Chapter IX based allowable stress value (42.2 ksi) there is a major difference. We can edit the allowable stress values in the input based on chapter IX values? I need expert advice.

Thanks

Yes, you can replace the allowable stress values loaded by CAESAR II with the values you wish to use.