US Registration for small vessels
US Registration for small vessels
(OP)
Hello,
I'm Canadian based, so please excuse my ignorance.
For small pressure vessels in Canada, we have a separate registration requirements (H-fitting). I'm trying to understand if there is an equivalent system for vessels in the United States (specifically in Tennessee).
As an example, we have a small vessel (less than 5 ft3) being shipped to and installed in Tennessee. Per National Board document NB-370, it appears that there is an exemption for vessels under 5 ft3. Does this mean no registration of any kind is required? Can we just ship the vessel to site and they can bolt it up?
Thank you,
Marty
I'm Canadian based, so please excuse my ignorance.
For small pressure vessels in Canada, we have a separate registration requirements (H-fitting). I'm trying to understand if there is an equivalent system for vessels in the United States (specifically in Tennessee).
As an example, we have a small vessel (less than 5 ft3) being shipped to and installed in Tennessee. Per National Board document NB-370, it appears that there is an exemption for vessels under 5 ft3. Does this mean no registration of any kind is required? Can we just ship the vessel to site and they can bolt it up?
Thank you,
Marty





RE: US Registration for small vessels
Quite likely, a vessel that is exempt per the exemptions in the ASME code would be exempt from state regulations as well, but you'd need to confirm that via state law.
RE: US Registration for small vessels
RE: US Registration for small vessels
RE: US Registration for small vessels
Code: ASME VIII-1
MAWP: 90psi @ 331°F
The specific state regulation: Tennessee state regulation.
Paragraph 68-122-105(a)(5) states: (a)This part shall not apply to the following boilers: (5) Unfired pressure vessels having a volume of five (5) cubic feet or less.
So, my question again, is any registration required for a small pressure vessel less than 5 ft3 in Tennessee? Could I ship a vessel there with an MAWP of 10,000psi but a volume of 4.9 ft3 with no registration?
(I'm just asking because it seems odd coming from a Canadian h-fitting background)
Thanks,
Marty
RE: US Registration for small vessels
RE: US Registration for small vessels
RE: US Registration for small vessels
The Category H fitting designation under CSAB51 is very poorly understood in my opinion. Lots of stuff gets separately registered as a Category H fitting when it is really nothing more than a wide spot in the pressure piping system which itself is registered and given a CRN. Category H is intended for articles which will be manufactured repeatedly for sale and hence need independent CRNs, not for one-off small "vessels" falling below the scope of ASME VIII. B51 is poorly written so the misunderstanding is widespread.
RE: US Registration for small vessels
Maybe that answers your question?
RE: US Registration for small vessels
Unfired pressure vessels:
a. Having a volume of 5 cubic feet or less;
b. Designed for a working pressure of 15 psi or less.
I always considered both conditions need to be met but now I'm not so sure.
Also it's not true that all states require ASME and NB registration. Some states don't even have pressure vessel laws.
RE: US Registration for small vessels
Regards,
Mike
RE: US Registration for small vessels
NB-370 is trying to summarize from the state laws. If you leaf through the state law however, those two exemptions are listed under separate lines as independent exemptions.
SnTMan,
I was hoping this would garner a quick response from the collective knowledge. I guess not, time to wade through the jurisdictional telephone soup.
Cheers,
Marty
RE: US Registration for small vessels
Good luck,
Mike
RE: US Registration for small vessels
RE: US Registration for small vessels