Buried Pipe Allowable Stress

[bonkers]

With reference to a buried natural gas pipeline road crossing, I have calculated the total combined stress on the pipe. I now have the % SMYS value. My question is what do I use for the maximun allowable limit for an ASME B31.8 location class (3)? Do I use the basic design factor(F) which is already used in the pipe design formula for an allowable limit? If so, this limit would be 50% SMYS but I have been using 62% SMYS from previous unsubstantiated sources. Does anyone know of a reference source?

Thanks for any help!
Bonkers

 

[BigInch]

B31.4 (I have 2006) combined stress and other limits are shown in TABLE A402.3.5(a) Where it is indicated as F3 = 0.9 * SMYS

Unfortunately I do not have a B31.8, so check that for a similar table... and please let me know what it says.

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"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

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