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ASME Section VIII Div I: Repair - Rewelding of A Coupon Back onto A Pressure Vessel

ASME Section VIII Div I: Repair - Rewelding of A Coupon Back onto A Pressure Vessel

ASME Section VIII Div I: Repair - Rewelding of A Coupon Back onto A Pressure Vessel

(OP)
I am seeking guidance for acceptable repair to a pressure vessel. In this instance, a fabrication shop punched a hole in the wrong spot of a pigging barrel (see attached picture). After notifying 3rd party inspection, they took the plug (same material grade, composition and thickness) beveled it back and shot 100% x-ray on the repair spot. Additionally they did a 14 hour hydro test at 1800 PSI on the vessel (1.5 x design).

I'm coming up short for answers when searching ASME Section III Div I. Is this an acceptable repair? If not, what, if anything, is considered acceptable?

Greatly appreciated.

RE: ASME Section VIII Div I: Repair - Rewelding of A Coupon Back onto A Pressure Vessel

I am not familiar with section III so I am not positive, but I don't think that will fly with the code or the client. The shell of the vessel is obviously out of round at the repair site. Is there a tolerance on vessel roundness? Is the fabricator a qualified R-stamp holder? I don't think anyone would let that slide as new fabrication. If I ordered a vessel, and that showed up on my door step I would not be a happy camper.

RE: ASME Section VIII Div I: Repair - Rewelding of A Coupon Back onto A Pressure Vessel

craigjw, this kind of thing happens fairly reqularly and the repair you describe is generally condsidered acceptable for Sec VIII, Div 1 work, assuming full penetration welding of course. Only relevant section I know of is UG-78.

Unfortunately the repair in your picture looks not good at all, as the owner I would not be happy.

Regards,

Mike

RE: ASME Section VIII Div I: Repair - Rewelding of A Coupon Back onto A Pressure Vessel

(OP)
SPDL310: I apologize, I meant Section VIII. Thank you for the response. I have asked one of my inspectors who is a CWI to chime in. So far we are stacking hands on rejecting this fab job.

SnTMan: That was also the only relevant section I could find as well. I agree, it looks like poor workmanship.

Thank you both for your replies!
-Craig

RE: ASME Section VIII Div I: Repair - Rewelding of A Coupon Back onto A Pressure Vessel

There is nothing in Section VIII to prohibit this type of fabrication repair to correct a nonconformance. The surface should have been ground flush to ensure no local stress concentration.

RE: ASME Section VIII Div I: Repair - Rewelding of A Coupon Back onto A Pressure Vessel

This is a heavy wall vessel and that valley left will not affect performance if meets Code for the over grind. The suck in may be for lock of pre heat and xrays will not see that. hopefully the inside looks same or better. I wary more on the design, those large reinforcing pads will not allow correct expansion-contraction.I'm not the greatest designer I just see things.

RE: ASME Section VIII Div I: Repair - Rewelding of A Coupon Back onto A Pressure Vessel

This is a common method of repair to a misplaced nozzle cut out in a Section VIII, Div. 1 vessel. When possible it is preferable to use the same cut out material to make the repair. You don't indicate whether this vessel was subject to PWHT, was it?

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