Dear colleagues:

I have a problem with a new pressure vessel designed in agreement with API 510 & ASME VIII div I STAMP "U", the manufacturer performed an additional hole for nozzle in top head, I request one hole in superior shell head at 0° and this was opened twice at requires location and at 270°, the manufacturer propose plug the hole (dollar plate) for repair the reactor , however I am not sure that this are correct, because:

A) API 510 8.1.5.2.2 Insert plates is a permanent repair but is for "process vessels that have been placed" in agreement with...
1 Scope
1.1 General Application
1.1.1 Coverage
This inspection code covers the in-service inspection, repair, alteration, and rerating activities for pressure vessels and the pressure- relieving devices protecting these vessels. This inspection code applies to all refining and chemical process vessels that have been placed in service unless specifically excluded per 1.2.2.

B) If the vessel was requested with "U" stamp, when the repair will do, the stamp shall be "R" and then the vessel can´t be considered like new.

What part of ASME Sec. VIII goverment this kind of repair?

I look forward to receive your valuable comments
Thanks in advance

Julio Rodriguez
PEMEX Refinacion
Project Coordinator

I don't know about API 510, but I might be able to help with ASME.

How are you attaching the plate? If it's welded then it's just an ordinary category A weld. If it's threaded in, then UG-43(e) applies. Either way, I don't see why the R-stamp would be necessary, unless you're saying it's already been inspected and U-stamped.

trottiey:

Thanks for your support & quick response, the plug will be with bevel & double weld (internal & external) , then the supplier will perform PT & RT. I´m agree with you if the vessel hasn´t been stamped "U", then " R" stamp don´t applies.

Ah. So then are you looking for the code that governs R-stamp repairs? That would be NBIC NB-23. I'm not sure if I've answered your question.

Yes, your support has been very useful to me. Thanks