HEX U-Bends under external pressure

[lgracio]

thread794-256857

Hi all,

Is it really necessary to calculate the external pressure of U-Bends? Can we assume the U-bends are self-stiffened as it is joint to the straight part of tube, so the weakest part is the straight long tube?

If we use TEMA RCB-2.31 I have seen many calculator programs (AutoPIPE Vessel) showing the formula to = t1*(1 + do/4R), but I cannot understand how the t1 is given in relation to external pressure.

Or is TEMA formula using t1 only considering the U-bends under internal pressure?

Main question is how to calculate the required thickness of U-bend under external pressure using EN13445 + TEMA?

I appreciate your experienced support.

Many thanks.
LG

LPSG-Engineering Solutions
Mechanical Engineer
Portugal-Setubal

 

[r6155]

See Toroidal shell in “Roark's formulas for stress and strain”.

Regards