Over the last 15 years I have been involved with numerous projects (predominantly oil & gas) that have had pressure components manufactured all over the world and shipped to site for installation.
When defects are discovered in supplied vendor piping, tanks or vessels they are usually repaired / reworked on site or if the schedule allows (and it is practical) they are returned to the vendor for repair.
Piping and to a lesser extent tanks usually prevent no problems as the sub contractors on site generally have qualified welding procedures and qualified welders available – if the items are still under warranty the welding documents are sent to the vendor for approval prior to repair / rework starting. If out of warranty then the client / owner or their representative usually reviews and approves the documents.
However, pressure vessels are a whole different ball game.
You do not generally fabricate pressure vessels on site so the majority of subcontractors will not have qualified welding procedures to cover repairs or rework.
What has happened numerous times in the past is the vendor will supply a repair / rework WPS and the welders will then perform qualification tests based on this WPS.
This is where I am looking for clarification.
QW-100.1 states “Any WPS used by a manufacturer or contractor that will have responsible operational control of production welding shall be a WPS that has been qualified by that manufacturer or contractor in accordance with Article II, ……..”
QW-103 states that wherever the words manufacturer or contractor are used they shall include installer or assembler.
Unless the vendor sends a representative to site to assume “responsible operational control of production welding” how can we, the “installer” use the vendor supplied WPS and be in compliance with QW-100.1 ?
For example, Vendor supplies a WPS with a critical heat input range and this is totally ignored by the on site manufacturer/contractor/installer/assembler.
That pressure vessel then explodes – who would ultimately be accountable / liable ?
The vendor who supplied the WPS, the subcontractor who conducted the repairs, or the main contractor who approved the use of vendor supplied weld procedures ?
Regards,
Shane
Shane, the lawyers would debate that one and all parties would lose however per your statement: "For example, Vendor supplies a WPS with a critical heat input range and this is totally ignored by the on site manufacturer/contractor/installer/assembler." In this regard I believe the site manufacturer/contractor/installer/assembler would be found negligent and thus the "ultimate guilty party."
In your current situation in the other thread I believe you should be looking very closely at ASME VIII if that was the constructing code. ASME IX gives very little clarity for that situation but I believe the site manufacturer/contractor/installer/assembler has very likely voided any warranty of the manufacturer and certainly the "liability" of the manufacturer is now significantly lessened now that the site manufacturer/contractor/installer/assembler has started destructive investigation. Just some friendly words, go forward cautiously, maybe even consider sending Walt an e-mail for advice.
An EDIT: In your scenario of the Vendor supplying the WPS to the manufacturer/contractor/installer/assembler for repairs, if the Vendor is not present to monitor and supervise implementing their WPS, ASME IX has not been complied with either.
Hi Jon,
Thanks for the response.
Have sent an e-mail to Walt for possible clarification.
On this particular project the vessels are fabricated in accordance with AS 1210 (Australian equivalent to ASME VIII Div 1) but welding procedures and welder quals are in accordance with ASME IX.
The example re: Heat Input was just that, a hypothetical.
Who would know if the original manufacturers WPS had or had not been complied with if the original manufacturer did not supervise (or maintain operational control) of the repairs / rework ?,
Regards,
Shane
Agree Shane and your point: "Who would know if the original manufacturers WPS had or had not been complied with if the original manufacturer did not supervise (or maintain operational control) of the repairs / rework?" is spot on. In any case if the original manufacturer was not there to supervise welding (this is "assuming" their WPS was used) then ASME IX has not been complied with and I keep bringing the point about warranty and stamping because these too would be voided under ASME VIII Rules which are similar to AS 1210.
To me this is pretty cut and dried. And it doesn't matter if the original contractor showed up to supervise the welding or not. That is not ASME's definition of operational control in IMO.
If you are going to demonstrate operational control those welders have to be essentially working for the orginal contractor. And they have to have been qualified by the original contractor, or at least the orginal contractor had to have had someone present when the quals were made and this participation has to be stipulated in writing.
And in the end the field contractor is responsible if this is not the case.
You're correct on the operational control concept Jeff. It's just been incorrectly accepted in some parts of the industry as discussed. It was originally conceived at the Savannah River Site when Westinghouse became the new Operator, taking over for DuPont who had built and operated the plants for maybe 40 years, Westinghouse wanted to assume ownership of the Dupont WPS/PQRs etc., There's a bit more to it than that of course but that was its beginning.
Shane,
Is the PV being installed in USA or Australia?
In the majority of states & jurisdictions in the USA, repairs to a PV require a contractor performing such repairs to hold an NBIC "R" stamp certification. By holding such a stamp the contractor also employees an AI who would be the one signing off on all welding procedures, NDE and subsequent hydrostatic testing of the repaired PV.
After such repairs have been authorized, made and signed off, the contractor would be responsible for failure of PV if failure is proved to be from repair.
It would be in court for a lengthy time no matter what and all would be guilty till proven innocent.
QCRobert
The ASME certification/stamp is only required in US, unless it is a regulatory requirement in your country. If you are in Europe, there are other rules for pressure equipment repair. You should ask your local authority who approved first place the operation of that vessel, what are their requirements for the vessel recertification and approval for use after the repair. For example, in Australia you have to follow the requirements of standard AS 3788, as stipulated by the goverment, regardless of what design code was the vessel designed to initially and you don't need any ASME or API stamp.
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