Not much happening in this forum at the moment, so maybe some food for thought....

I recently dealt with a compressor discharge line 24" dia, 1.75" thk A106B. The line was not insulated. Four fluid temperature probes at the machine nozzle all registered 170 deg C but the pipe surface, accurately measured was 70 deg C. Inner pipe wall temperature is unknown. This significant thru' wall temperature differential clearly exists in heavy pipe, yet the induced stress is not generally recognised. It must be axial tensile at the pipe outer wall, thus additive to longitudinal bending and pressure stresses.

What do you think ?