Hi Jeff,
The pipe was manufactured as per purchase order (as welded) and it was rolled plate with a longitudinal seam in accordance with API 5L Grade B.
Someone on the clients team must have read about the stress corrosion problems associated with Amine service and carbon steel pipes and the need to PWHT.
So, the client decided all C/S piping must be subject to PWHT (2 years after initial order and supply).
We now have a huge amount of 450 NB Sch 10 (6.35 mm) on site that does not have PWHT. They are going to weld and PWHT circ welds on site using one of the site contractors WPSs but there is nothing to cover the manufacturers welds.
That was where my original question came from - would a PQR using 25 mm plate (SA 516 Gr 60) and GMAW/SAW be even remotely applicable to our situation.
Both P1 Gr 1 and thickness is no problem so code compliant (ASME IX) but something does not feel right - just cannot put my finger on it.
Regards,
Shane
It sounds like you need an ECO, and send all of that pipe to a heat treat outfit so they can cook all of it in an oven. extra cost billed to the customer of course.
Shane,
IMO
To you its not a PWHT. You didn't do the welds.
To you its a heat treat of a base metal the same as if you decided to normalize a plate that has been hot rolled.
Therefore, its not an ASME Section IX issue. Its a customer specification issue.
However, by agreement between you and the customer you need to establish a testing verification regime and acceptance criteria. And you need to protect your companies interest with disclaimers.
I don't think there is anything ethically wrong. Its just engineering. But there is no Code compliance or non compliance for that matter involved.
Its an engineering judgment call, IMO.
Somebody may be able to help us out here, there may even be an API standard that accomodates this type of engineering application.
The only way to make this cleaner is if the pipe manufacturer performed the heat treat in compliance with WPS they have, or if they subcontracted you to do the PWHT and then you did it within their system and procedures.
I jus think that technically speaking once you go from one contractor to another its no longer a WPS PWHT issue. You can't verify their welding and so have no WPS.
By jarcher
Date 05-27-2011 20:08
Edited 05-27-2011 20:13
Looks to me be an expensive proposition any way you slice it - either stress relieving all that pipe, with the problems that ensue from that, or applying some kind of internal epoxy coating. Either solution being payed for by the customer. My money is on the epoxy being cheaper. Either way, from what you've said, it's the customer who mispecified and should pay the freight. If, as you say, its a P1 to P1 weld backed by a good WPS/PQR and the construction code doesn't require PWHT, it's not a quality compliance issue - your company fulfilled its contractual obligation, assuming the customer had responsibility for the metallurgical engineering. BTW, buyer's remorse is becoming very common in the oil patch since Mocondo.