Welded Manways on ASME VIII Div 1 vessels
Welded Manways on ASME VIII Div 1 vessels
(OP)
Is the weld on a 2:1 SE cover on a manway for an ASME VIII Div 1 vessel covered by the Code.
We have several large stamped vessels to be installed in a nuclear waste clean up plant, that after shop hydro and National Board stamping are delivered with a tacked welded 2:1 SE head as a manway cover. All the piping connections on the vessels are butt welded and it is necessary to inspect these vessels for internal cleanliness prior to placing them in service, hence the loose manway cover.
The vessels are designed for 40 years life and are in radioactive service and will therefore not be subject to further inspection once commissioned. In fact the vessels are enclosed in totally inaccessible cells within the processing buildings.
The question is, does the welding of the manway cover need to be covered by ASME VIII by way of an R stamp or can this weld be considered a piping weld under ASME B31.3 similar to all the other butt welds connecting the piping.
This is probably territory for an ASME interpretation but I'm curious to know if anyone has encountered a similar situation previously.
We have several large stamped vessels to be installed in a nuclear waste clean up plant, that after shop hydro and National Board stamping are delivered with a tacked welded 2:1 SE head as a manway cover. All the piping connections on the vessels are butt welded and it is necessary to inspect these vessels for internal cleanliness prior to placing them in service, hence the loose manway cover.
The vessels are designed for 40 years life and are in radioactive service and will therefore not be subject to further inspection once commissioned. In fact the vessels are enclosed in totally inaccessible cells within the processing buildings.
The question is, does the welding of the manway cover need to be covered by ASME VIII by way of an R stamp or can this weld be considered a piping weld under ASME B31.3 similar to all the other butt welds connecting the piping.
This is probably territory for an ASME interpretation but I'm curious to know if anyone has encountered a similar situation previously.





RE: Welded Manways on ASME VIII Div 1 vessels
Another point of view: when a weld connection of piping is treated per piping code, then you have a piping system with an imposed code of practice, but which would be the code of practice of the manway cover?
prex
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RE: Welded Manways on ASME VIII Div 1 vessels
RE: Welded Manways on ASME VIII Div 1 vessels
RE: Welded Manways on ASME VIII Div 1 vessels
Since it is not a repair or alteration, ASME stamping may be required by a PP piping stamp holder,
any future welds after stamping is not your responsibility,
unless you have contracted it.
If you hold your Stamp VIII-1 for field work, you can perform the welding on site, requiring a new certification,
then it may be easyer not to shop stamp but when the job is finished on site. It looks to me that fiel work is not your case.
GB
RE: Welded Manways on ASME VIII Div 1 vessels
Anyway. If it is a manway cover - presumably it can be removed. If it can be removed it can be hydro tested independently. It can be cleaned etc.
Is an existing cover to be reused. Then this has been tested already and can be used.
I would be looking at whether the manhole cover can be used in service or if it was a transport cover.
RE: Welded Manways on ASME VIII Div 1 vessels