Blind Threaded holes tubesheet

[Ehiman1]

Hello,
I have a heat exchanger where tubesheet has blind threaded holes where a flange is bolted.
Does it necessary to calculate the length of the threaded holes in the tubesheet?
It doesn’t exist a formula in tubesheet chapter to check it according to ASME.
Can we follow good engineering practice?

 

[Cobra17]

UG-43(g) gives tapped holes for studs, but it's more for connecting to the shell of a vessel. You might also want to check the Handbook of bolts and bolted joints, pgs 136-138

 

[SnTMan]

Ehiman1, if you are under Sec VII, Div 1 and I imagine your costruction correctly, following UG-43(g) would be sufficient I'd think.

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[Ehiman1]

Thank you for your help.
UG-43 is based on ratio of allowable strength of the materials (screw and component) and diameter oh the bolt/hole and everything is clear.

In these days checking the different codes I also found a similar formula in EN-13445-3 code, but I don’t understand why the considered ratio Rp,screw / Rp,component seems to be based on proof strength of the materials and not design strengths as per ASME code.
Does it a wrong interpretation from my side? Because two formula lead to very different values of the length to be considered.

Chapter is 11.4.3.3 with
L = 0.75*do*Rp,screw/Rp,component.

But Rp should be proof strength and not design strength of the material.

 

[MJCronin]

I believe that TEMA will tell you what you are looking for ...

MJCronin
Sr. Process Engineer