Expansion Joint in Heat Exchanger

[Tankman650]

I have a Heat exchanger (TEMA BEM) with an expansion Joint. The analysis per TEMA 8.xx is rather involved. I have decided to analize using FEA. I can set up the model and do the analysis and feel comfortable with the results rather than go through the TEMA calcs.

My question is has anyone compaired the TEMA formulas with FEA???

Thanks

 

[prex]

Never done that, but wouldn't advise you to continue on that path: you will need to adopt the stress classification criteria of ASME VIII Div.2 (expansion stress limited to 3*S), but any back link to TEMA criteria will be hard to find. prex
motori@xcalcsREMOVE.com

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Online tools for structural design

 

[vesselguy]

I totally agree with prex. Seems like prex has been around the block couple of times like me.

Anyway, I know it is now very easy to use a tool like FE/Pipe to model expansion joints and do a FEA. But, the catch is to tie it the aceptance relationship from TEAM to Div. 2, Appendix 4. It can even be tricky for experienced guys. Just do the TEMA cals in MathCAD or something like that and be done with it. I've done it and it's not that hard.

Also, many boiler's branch engineers know the TEMA rules and would make their job much easier (translates to accepting your design easier and faster) if you just follow the typical rules.

FEA should be used only when 1) by an experienced engineer and 2) a closed form solution is not available.
Just because software development has made it such that even a dummy (like me) can use it without a Masters degree on FEA does not mean we should use it on everything.

 

[Raydel]

Try using CodeCalc by COADE. It has an expansion joint analysis for heat exchangers built into the sofware. You may find this useful. If you know anyone with this software offer them a beer in exchange for a design.