In ASME B31.1 1986, Section 104.8.2 Stress due to Occasional Load, and Section 104.8.3 Thermal Stress Range has an option to take credit for SAM load case(s) moments in equation 12 or equation 13 (see definitions for Mb and Mc. What is the correct method to apply the option of analyzing SAM load case moments in Eq 13 instead of Eq. 12 in the code using AutoPIPE.
At this time AutoPIPE does not have an automatic option to switch SAM load case from Code equation 12 to 13. This has to be performed manually with the following Steps.
Step 1 - Create a model with Piping code = ASME B31.1 1986, SAM load case(s), and Analyze the model.
Step 2 - Select Tools> Combinations> Code Comb tab and delete all default combinations = (SUS)+S1 to (SUS)+S10.
Step 3 - Create new user code combination(s), as SAM is unsigned and thermal moments are signed, ABS SUM may be selected as the combination method.
Create additional combinations similar to above as needed.
Step 4 - Review Results.
By deleting the combinations (SUS)+S1..S10, the SAM load case were removed from Eq 12 and was added to Eq 13 with the new User combinations created in Step 3 above. In addition, this version of the program shows Ma as a term in the online help code equation section for "Stress Due to Occasional loads", this is a typo and should be replaced in future versions with correct term Mb.
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