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Repair WPS

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metboss

Petroleum
Sep 12, 2012
152
Hi All,
We have one weld repair job and our contractor submitted the repair specific WPS. But, they submitted the original PQR which is applicable for production welding WPS.
The details are as: Repair welding WPS (process SMAW and SAW) no PWHT, code ASME IX
Production welding PQR (process GTAW, SMAW and SAW) no PWHT, code ASME IX

For repair WPS, does it require to qualify the process with all testings (side bend, tensile,RT) again? OR original production welding PQR is enough to support to repair WPS? OR a separate PQR is required?
Pls.any insight? Thanks.
 
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What does the repair consists of?
If you can make the repair using the parameters of the PQR, for me there's no need for additional PQR's.
However, if it requires special processes or skills that are not tested using the original PQR, it's clear you need additional testing.

Obviously, if the root of the PQR is done using GTAW and the repair consists of root welding using SMAW, that's an immediate fail.
 
What I’ve always had to submit is weld repair procedure, outlining the steps required to make a quality repair, and not a weld repair specific WPS.

This procedure always includes details of the joint prep, welding - which typically includes the originally approved WPS, and required NDE as a minimum.

As mentioned above, there shouldn’t be a need for other PQRs unless there is something unique not captured in the original PQR.

The devil is in the details; she also wears prada.
 
This question has fascinated me for long, still does. Is a separate PQR required for repairs? That is, is it needed to make a coupon, grind out some of the weld metal, and fill it again, and then do tension and bend tests? In other words, is repair required to be simulated in procedure qualification?

Here is what i learned, after some digging in codes.

1. Section IX does not require any simulation of repair. That is, the same WPS used for initial weld can be used again. Somebody once asked a very interesting question in interpretation IX-17-04: a weld is made up of gtaw at the root, followed by smaw for remaining thickness. Is it permitted to repair in the SMAW portion with GTAW process, within the deposition thickness limits of gtaw? The answer given in interpretation is yes. So,this is some valuable context. (Though, that Sec IX permits this - is a little intriguing).

2. Some codes, such as KTA 3211.3, ask for repair to be simulated if the repair is going to be done using a different process than the original one. For example, in the example cited in interpretation IX-17-04, repair with gtaw in a smaw deposited weld would require simulation of repair in the procedure qualification.

3. Logically speaking, the approach of KTA codes, as indicated in sl no. 2 above, makes greater sense. And so that is what i adopt in my work place. If the process is different, a simulation is required.

4. If the process is same, i go with what DVWE says. A repair procedure is usually asked, by some customers, which should detail how/how much digging is to be done, what NDE should be done on the dug up surface, and what NDE should be done after filling up of the repair groove. WPS, however, can be same as the original one.

Excuse me for the long reply, please.
 
It depends on the governing code if one applies to the work required.
ASME B&PV code sections apply to new construction. NBIC generally comes into play when a vessel is in-service and a repair or modification is needed. They typically refer to the ASME code section for qualifying the WPS used for the repair.

On the other hand, most of the work I do isn't covered by AWS or ASME. Some of the equipment is 100 years old. Many of the components are steel castings. The WPS is very specific to the component being repaired and there is no "excess" material available to "qualify the WPS". Best practices and experience is what determines how the repairs are carried out. Some of the repairs can be alloy steels similar to 4130 up to 17-inches thick. There isn't a lot of published data to work with, but we do the best we can and so far, over the last twenty years, the repairs have been successful when the contractors doing the work follows our direction. How do you ensure the contractors follow the WPS? You keep a watchful eye on the work while it is in-process. Once the repair is complete, it is too late. People tend to be forgetful when no one is overseeing the work.

Best regards - Al
 
Thank you all for your insight. We have decided to go ahead with the original WPS (original production weld) for repair too as "essential variable & welding process (where weld repair required i.e. SMAW)" are same.
Thank you again for valuable time in responding to my query.......
 
My contractor done SAW welding repair By SMAW welding process,in section ix where its mentioned to support my statement or how can i expressed my opinion them by ASME section IX clause?

Regards,
HC.
 
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