Minimum thickness of a cover with bolt holes that do not fully penetrate

[Stephen Max]

Hello everyone,

I am designing a pressure vessel according to division one rules. It is a special purpose pressure vessel that will have a door to allow access into the PV after depressurization. The door opens internally and is sealed against the PV by the operating pressure. I have specified the thickness of the door according to UG-34, eqn 3.

To complicate matters, the outer surface of the door will have other parts bolted to it. Thus there are bolt holes on the outer surface that do not penetrate the full thickness of the door.

The question is, do I need to increase the thickness of the door to account for the bolt holes? I haven't been able to find anything in the div 1 rules that pertain to external holes in a cover that do not penetrate the full thickness of the cover. There is a rule for a peripheral gasket groove, but I don't think that applies, or does it?

Is this a case where instead of following a specific rule I could do a stress analysis to verify safe levels of stress at operating conditions?

Thanks.

 

[chicopee]

Weld metal boss on the external surfaces of the PV and its door and thread them. The thicknesses of the PV and its door are left intact.

 

[SnTMan]

See also UG-43(d) for some guidance.

Regards,

Mike

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

 

[Stephen Max]

Thank you! That is exactly what I was looking for.