Pressure Vessel Rerating

[InspectorWilly]

Got an ASME VIII D1/NBIC Question. So, my engineers forgot to send out updated mechanical calculations, or to update the hydro test pressure in the drawings. The equipment was fabricated per the new calcs (material thicknesses and such), but hydro tested to the old values, which was a much lower pressure (about 70% of required). The equipment has already shipped to the customer. The question is, can we submit an R-2 to cover the new calcs and have an R-stamp shop perform the hydro at the higher pressure? Or do I need to get the equipment shipped back to the shop and reperform the hydro and write up a new U-1? The equipment has not yet been placed in service. Thanks in advance!

-Willy

 

[fegenbush]

Since the U-1 is signed by the AI and the unit was released from the shop, I would use an R-2 even if you get it back in the shop. Some may say that it looks poorly on them to have a new vessel with a rerate tag on it, but my opinion is that proper documentation of what actually happened looks like an honest company following industry standard procedures.

 

[InspectorWilly]

fegenbush,

I agree that the R-2 is cleaner, but more to the point, which jurisdiction does this fall under? NBIC, or ASME?

-Willy

 

[metengr]

The equipment has already shipped to the customer. The question is, can we submit an R-2 to cover the new calcs and have an R-stamp shop perform the hydro at the higher pressure? Or do I need to get the equipment shipped back to the shop and reperform the hydro and write up a new U-1? The equipment has not yet been placed in service

This is NBIC code space because the vessel has been completed, regardless if the vessel has or has not been placed into service.

 

[metengr]

You can also check API 510 since this is a pressure vessel.