TRUNION MODELING IN CAESAR II

Posted by: NAG

TRUNION MODELING IN CAESAR II - 10/17/19 09:20 PM

Hi I want to know the trunnion modeling in CAESAR II software.& what are the important points to be check after modeling.

Please share if you have example C2 model & trunnion checking excel sheet. I need both trunnion in horizontal pipe as well as trunnion in elbows.
Posted by: Michael_Fletcher

Re: TRUNION MODELING IN CAESAR II - 10/18/19 11:27 AM

Trunnions on straight pipe can be modeled as unreinforced, or if needed, reinforced tees, but may optionally be analyzed via FEA.

Attachments on tees should have their SIFs calculated via FEA, such as FEBend.

Find more info here:
https://coade.typepad.com/coadeinsider/2016/10/20161206-caesar-webinar.html
Posted by: NAG

Re: TRUNION MODELING IN CAESAR II - 10/19/19 01:23 AM

hi Michael,

thanks for your reply.

As you mentioned FEA method has option to verify the trunnion.

But without FEA we cannot do manual calculation. We don't have FEA software.

Please suggest me alternative method.
Posted by: Michael_Fletcher

Re: TRUNION MODELING IN CAESAR II - 10/21/19 09:15 AM

Before I had access to such software, I would state the following: "Due to the inability to verify the SIFs at attachments on bends, I cannot recommend installing trunnions on bends. Industry leaders advise me that SIFs can range from anywhere to below 1 (noting that minimum SIF then becomes 1) to 10 and possibly even higher, depending on the geometry of the bend, trunnion, and weld, and calculating SIFs on such geometry are outside the scope of the piping to code to calculate. Because of this fact, CAESAR presently does not have the functionality to calculate such SIFs itself, and will be unlikely to until the piping code includes it."

As such, I gave them 4 options:
1. Buy the software.
2. Expect attachment on an elbow to be rerouted.
3. Accept liability for ignoring best recommended industry practice.
4. Pay someone else who has the software to do the work.

As a side note, there are plenty of other configurations and fittings that the piping code does not directly address, either, including laterals and Y-joints.
Posted by: NAG

Re: TRUNION MODELING IN CAESAR II - 10/21/19 10:14 PM

Hi Michael_Fletcher ,

Thank for the detailed reply.