Alteration of a top cover on an ASME VIII Div. I Pressure Vessel

[ProcessEng69]

Hi there,

due to a defect we need to replace a bolted flat top cover on a U-stamped pressure vessel at our client's site. The vessel is located in Texas and has no NB registration (not required as per Texas jurisdiction).

Is it possible to replace the bolted cover with a new one (no standard blind flange) without the R-stamp? Are there any further regulations we have to follow for this alteration? Do we need to re-hydro test the whole pressure vessel again after mounting the new cover?

Any information on this topic would be very helpful!

Thank you very much in advance.

Have a nice day!

 

[metengr]

Since Texas does not regulate pressure vessels, it is up to the client and/or the insurance company who insures the equipment to decide on what needs to be done in terms of code to follow and documentation requirements. If it were me, I would require either an R-Certificate holder following the requirements in Part 3 of the NBIC or API 510.

 

[gr2vessels]

I understand this is a new equipment that has not been yet in service, but needs alteration on site. Well, the new cover is/was not part of the originally completed vessel and has not been hydrotested to the code. Accordingly, a new design, fabrication and proving process has to be done, in order to satisfy the code requirements. Anything less than that would be a compromise to the safety of equipment. Indeed, it is up to the Client in Texas to specify the alteration process, but common sense will prevail and as mentioned above by metengr, the R stamp and API 510 should be followed. Also, yes, the new cover will have to be hydrotested with the whole assembly.
Cheers,
gr2vessels

 

[ProcessEng69]

Thank you for your quick help, guys.

The vessel is still in service. The defect on the top cover is not safety relevant. We will get in touch with our client to clarify how we shall proceed with the alteration of the top cover.

Have a nice day!!

Cheers,
ProcessEng69