Iv tried to search for this answer but couldnt find what i was looking for.

My company did a stress analysis on some piping lines to determine if slug flow was over stressing the system as a study. We ran both static and dynamic cases and presented our findings and that was it for the study. Now our client wants us to recommend changes but our stress guy who originally did the study is no longer with the company. Iv reviewed his work as i wanted to be sure what we were submitting would be correct. He calculated slug flow forces and inputed them into time history analysis correctly but i think he might of set up the non-linear restraints wrong in the dynamic case.

My question is, from the static case where we had guides and limit supports with various gaps, and places where there were just +Y supports, is it necessary to change the model so there are no non-linear supports? Such as, is it necessary to make all +Y supports into Y supports, and change all gaps on guides so there are no gaps so the pipe is held down?

The manual says Static Load Case for Nonlinear Restraint Status: Most often the user selects the operating case to set the nonlinear restraint configuration.

I tried both ways, and i was getting huge stress values when i have 0 gaps and the stress was many multiple times low when i left the gaps in there and selected the corresponding operating case.

Thanks
joe