Tied Tandem Expansion Joint

Hello All,

Please see the attached expansion joint data sheet. I have reviewed a couple examples/theories on possible ways to model this assembly, but non of them match this type of arrangement. Specifically when they are tied to the elbows.

Any suggestions or guidance on the proper way to model this assembly would be greatly appreciated.

Thank you,

Jeffrey.

It depends on how complicated you wish to get here. The tie rod model is the only thing different here.
You could either:
1 - Instead of modeling the tie rod, just do not specify an effective bellows diameter (to ignore the pressure thrust which will be carried by the tie rods) and check the elbow displacements - they should not move towards or away from one another
2 - model the tie rods as a single element down the centerline from one elbow node to a CNode'd restraint to the other elbow node
3 - a really complicated model with all tie rods modeled around the pipe

Dave,

I appreciate the fast response. From reading your post I believe we are on the right track on how to approach this and compare the different methods.

Thanks,

Jeffrey.