U stamp required for this vessel?

[wangzh2k]

Hi All,

I would like to confirm something in U stamp requirement to a small pressure vessel.

The design pressure is 125 psig
The shell will be 12 inches pipe sch40
Ends will be cap in sch 40.
Length of the shell will be 4 feet.

Per my understanding to U1(c)(2)(i) of ASME VIII-1, it is within the scope of VIII-1, the stampe is required.

Any comments will be appreciated.

 

[metengr]

Your assumption for a U-stamp is correct for this vessel.

 

[jte]

wangzh-

Yes, your interpretation is correct. If you are getting the argument that it is built of piping components and thus is a pipe, take a look at Interpretation VIII-1-04-46 in Volume 56, 2006.

jt

 

[wangzh2k]

Thanks all

 

[JStephen]

Note that falling within the code limits doesn't always mean it must be a code vessel. Some jurisdictions don't require vessels to be stamped, and if you're outside the US, it may fall under some other requirement. Also, I believe pressurized water tanks are exempt even though they otherwise fall within the requirements.