Joint Efficiency 3

[Estassoc]

I'm designing an aluminum pressure vessel. Shell and
head material is SB209-5083-O. Shell weld is Type 1
and torispherical head is seamless. There are no radiogragraphy for this vessel. What efficiency will
I use for the required minimum thickness calculation
for the head?

I'm using a 0.70 efficiency for the shell thickness
calculation.

Appreciate any help on this matter.

 

[gr2vessels]

Hi Estssoc,
The Table UW-12 specifies E=0.7, as you mentioned, for no radiography design of the shell. Since the head is seamless, use E=1 for the dished end calculation.
cheers,
gr2vessels

 

[Shmulik]

gr2vessels,
Seamless head efficiency is NOT 1 unless UW-11(a)(5)(b) requirements are met.

When UW-11(a)(5)(b) requirements are not met (as it seems here), E head = 0.85 from UW-12(d)

http://www.authorizedinspector.com/Joint Efficiencies.htm

 

[Estassoc]

Thanks guys. Appreciate the help.

I'll use 0.85 efficiency per UW-12(d).