When liberal stress allowance is turned on, the thermal expansion stress range is 93% of the B31.3 Code allowable. The maximum sustained code stress in the model is 8% of the sustained allowable. There is thus "a lot" of "stress" available to "go over" and help out on the allowable stress range. When the liberal stress allowable is turned off (in the configuration file), my thermal expansion stress range is 144%. I can't rationalize why this is OK. Is it OK?