Craig,

At this time, you would have to ignore the bending components and sum up the stresses and then compute the membrane stress intensity (Pl + Pm). It would be nice to implement the stress summation in WRC-297 module, similar to that in the WRC-107 module.

The loads that you enter should also be sustained (such as from weight or internal pressure). The stresses generated due to thermal expansion loads are categorized as Q and should be summed up to Pl + Pm + Q (membrane + bending).

In WRC modules, the Pm stress intensity is just the stress due to internal pressure. For a cylinder the maximum value is the hoop stress.