I am analysing the piping at a receipt station for a 42" X70 gas pipeline. Pressure elongation is significant and therefore i have included bourdon effects in the analysis. When this is activated Caesar applies the strain to all load cases with pressure. Therefore i am having an issue with failure at some tee intersections in the sustained case (W+P1) due to the elongation of the pipeline. By my understaing, this elongation is a self limiting load and therefore it seems overly conservative to require the stresses resulting from this to meet the sustained allowable.

To treat this as a self limiting load in Caesar, the only option i can see is to determine the temperature rise that is equivalent to the pressure elongation and apply this temperature to the model so that it is treated as an expansion stress.

Am I correct in believing the stress due to pressure elongation does not need to be applied to the sustained case and if so, can anyone provide some advise on how they have delt with this situation?