Dear all,

Can anyone please guide me how to build an expansion joint with below requirements,
1. 52 inch diameter
2. 300psig (20bar) is the line design pressure
3. Untied
4. Metallic
5. Preferable material - 316

While building the same, I am getting an error message - "joint requested is not available".

Regards

Try reading the Expansion Joints modeling procedures in the Applications Guide accessible from the Help menu in CAESAR II. If you still have difficulty understanding the procedures (which is pretty straight-forward if you follow it) then you can ask for further help.

Regards,

Dear Nidh,

The expansion joint database contained by the CAESAR II expansion joint modeler has an extensive number of pre-engineered bellows elements. Unfortunately, 52” diameter is not one of them as it is an off size and the pressure is very high for this diameter and hence the error message. You’ll have to get assistance from an EJ manufacturer. You can submit your request at Pathway’s website (myej.com) in the “ask the expert” section.

Dan Edgar

PS – You’ll have to include the temperature and movements for the bellows.

Dear Nidh,

If you wish to model this, you may as well just put a very low stiffness in for a simple flexible connection, because the pressure thrust forces are going to dominate the model behaviour.

You have stated the bellows is untied. The pressure thrust for this unit will be massive - at 52in size it is about 2740 kN (equivalent of about 280 tonnes mass). In practice it will be greater because the diameter of the bellows convolutions is greater than the pipe size.

So you will require huge restraints somewhere either side of the expansion joint.

Perhaps you should re-think this application.