UHX 14.5.9 Step (9)

[SyedZainAli]

This is wrt ASME S8D1 edition 2013 para UHX-14.5.9(b) which deals with checking the tubes for buckling stress in case of a floating head heat exchanger.

Can anybody explain the reasoning/logic behind this para which is relevant for floating head shell and tube heat exchangers?

As this para is valid for FLOATING head heat exchangers, I am unclear as to how compressive stresses and correspondingly how bucking stresses are induced in the tubes.

Thanks in advance to share your perspective.

 

[SnTMan]

SyedZainAli, I have never understood this either. I suppose it could be due to (slightly) unbalanced shell presure load on floating tubesheet, or sliding friction of floating head (although apparently no data for it) or some effect I don't see at all.

I can't believe it amounts to much.

Regards,

Mike

 

[SyedZainAli]

Mike
Yesterday i was designing a shell and tube exchanger with AES configuration this error came, to eradicate this error i increased the the thickness of Fixed tubesheet from 150 mm to 200 mm and then error gone hence i am searching for the right solution this may lead us to avoid that useless increase in the thickness of tubesheet coz it impacts the total cost



thanks for your share
Syed Zain ALi