"R" Stamp required or not? 4

[ET50]

We recently recieved a pressure vessel and installed it in our system. Before actually putting it into service we discovered a pinhole leak on one of the weld seams on the shell during a Nitrogen purge/leak test of other devices. We sent the vessel back for repair, and it arrived back without an "R" Stamp or other documentation. Is this legal given that the vessel never was commished into service in our system, or does it require an "R" stamp because it was initially inspected, hydrotested, and "U" stamped regardless of the fact it never officially went into service?

 

[jtseng123]

We have a new vessel shipped from California to Colombia. Plate got damage after arriving Colombia, and repaired with R- stamp.

 

[vpl]

What does your ANI say?

Patricia Lougheed

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[metengr]

The weld repair should have been performed either by an organization holding an R-Certificate from the National Board or under API 510.

Once a pressure vessel is completed, (stamped, hydrotested and witnessed b y the AI) it is no longer under the scope of code of construction, period. The vessel can sit idle for years and not be commissioned.

 

[ET50]

Metenger,
Thanks, that was my understanding as well. Because this is the first time we have had this issue, I just wanted to make sure my understanding of the code was correct before contacting the fabricator tomorrow.

 

[metengr]

ET50;
If this is indeed a nonconformance I would suggest you have the repair organization supply you with a qualified welding procedure specification and perform surface and radiographic examination to ensure suitable weld repair. You are going to need to assemble as much information regarding how the weld repair was performed and post weld repair NDT for acceptance of this nonconformance.

Your other other option is to hire an organization with a current R-Certificate and have them re-repair this location.

 

[ET50]

Just heard back from the fabricator and they said because the vessel didn't require PWHT or radiographic examination to begin with then it doesn't require an "R" stamp. They are saying that it is a minor weld restoration per UW-38 and UCS-56 and that since the weld didn't need to be replaced, cut out, or new material put in place it doesn't qualify for an "R" stamp.

I'm only trying to make sure they aren't taking advantage of us since I'm not an ASME expert. Having the above new information does this sound reasonable or they just trying pull the wool over our eyes. This is a small CS horizontal vessel (24" Dia x 48 overall length) with 150 psi design pressure, and basically ambient temp.

Thanks in advance!

 

[metengr]

ET50:

Just heard back from the fabricator and they said because the vessel didn't require PWHT or radiographic examination to begin with then it doesn't require an "R" stamp

.

Incorrect assumption and no understanding of code rules. They need to review Part 3 of the NBIC under Weld Repair. Minor or major repair, when an arc is struck you need an R-Certificate, period.

As I mentioned this vessel is no longer under fabrication because it is COMPLETED. The fabricator is unaware of ASME code rules. Go back and cite to them UG-99 a) 1 of ASME Section VIII, Div 1.

 

[jtseng123]

Metengr,
If I remember correctly, someone in the forum many years ago saying if the original WPS/PQR is applied, no need for R-stamp to repair a crack seam or nozzle. Is that a true statement ?(we do apply R-stamp for repair)

 

[metengr]

jtseng123;
No, this is incorrect.

 

[Christine74]

Since the vessel was never actually put in service I don't see any reason why the original manufacturer can't make the weld repair, re-hydrotest the vessel, and re-sign the Manufacturer's Data Report.

If the exact same thing had happened but the vessel had never left the shop I can guarantee that no "R" stamp would be applied.

-Christine

 

[Christine74]

Also note that paragraph 1.1.1 of API 510 specifically states "This inspection code applies to all refining and chemical process vessels that have been placed in service unless specifically excluded per 1.2.2."

 

[jtseng123]

Ny project manager says " Oh yes, you need R stamp"
My construction manager says " Oh no, you don't need to".

 

[metengr]

Since the vessel was never actually put in service I don't see any reason why the original manufacturer can't make the weld repair, re-hydrotest the vessel, and re-sign the Manufacturer's Data Report.

This is not permitted by ASME Code.



People are mixing apples and oranges. IF an ASME code stamped is completed - stamped, hydrotested and signed data report the vessel is COMPLETED by ASME Code.

Any welding after this point if in the shop, on a barge, in the field etc., must be done by a qualified organization with an R-Stamp if done to the NBIC) or other in-service code.

 

[gtaw]

The original post never stated this vessel was a code stamped vessel, nor was it stated whether this vessel is located in a state or location where an ASME stamped nameplate is required.

I was the fabrication manager for a company that fabricated both code stamped and unstamped vessels. Only the code stamped vessels were required to be repaired in accordance with the NBIC. Those vessels with a code stamped nameplate that were damaged, after the AI witnessed the hydrotest and all documentation was completed, during loading, shipping, unloading, etc. were required to be repaired under the auspices of our "R" stamp.

Vessels sold to clients that did not require the vessel to have an ASME stamped nameplate, even though they were designed and fabricated per ASME, did not require final inspection by the AI nor did the AI witness the hydrotest. Repairs to those vessels that were not require an “R” stamp.


Best regards - Al

 

[metengr]

The assumption WAS a code stamped vessel since it was described as a pressure vessel. Regardless, either API 510 or the NBIC should be used for guidance for weld repairs otherwise you take significant risk.

 

[davefitz]

as I read NB23 part 3 par 3.3.2, routine repairs do not need R stanping, but must be recorded on an R-1 form andnoted as routine. Prior permission by the AI is needed prior to avoiding the code inspection and stammping for a routine repair. If the repair requires more NDE than visual , or PWHT,it is not routine.

 

[jtseng123]

gtaw,
I have a real case. A code stamped vessel fabricated many years ago, never put to service. Another company bought this vessel and shipped to overseas, and got damage in shipping. They hired a third party U/R stamp qualified vendor to fix the damage, for sure it involved welding and NDE. Is the "R" stamp required to be added to the original U stamp ?
What you say " ...were required to be repaired under the auspices of our "R" stamp" may not always happen, especially when it is shipped to overseas. We also have the original vendor went bankruptcy.
However I understand your point is the "warranty" issue. Let's put that aside for now.

 

[ET50]

GTAW,

In the original post I mentioned it was "U" stamped. It was manufactured in California and could literally be in sevice anywhere in the world so it is also PED certified. It's final destination is determined when assembled into the system after an order is placed.

Anyway this subject is still open and unresolved between the manufacturer and us. Hopefully a resolution will take palce in the next week. I'll post the final outcome. In the mean time any other info is appreciated.

 

[Duwe6]

jtseng123 for 'full' R-stamp repairs, or any Alterations your R-stamp Repair contractor will attach another, R-Stamp, plate. If the Code Data Plate bracket is big enough, they will attach the Repair plate beside/below the original U-stamp plate. And an R-1 form for Repairs, or an R-2 for Alterations will be completed and signed by the contractors QC Mgr and their AI.

If the Repair contractor's AI deems that the repair is inconsequential enough, and 'calls' it a Repair-of-a-Routine-Nature, only the R-1 form is completed. No R-stamp data plate required.

Some of the above folks are over-interpreting API-510 and NBIC on the subject of hydro. If the repair area is truly a pinhole, the only way the contractor's AI will require a full hydro is if he is VERY unsure of himself, is mad at the contractor, or mad at you. The purpose of a hydro is to proof-test the design and fabrication of a vessel, to make damn sure that the vessel will not go BOOM in service. Minor repairs do not change the pressure capacity of a vessel. Remember, we are allowed to add a 2"NPS nozzle without calculations or reinforcement, meaning that 2"NPS-sized holes will not hurt the pressure capacity of a vessel.