mistake in drilling

[fazel2]

we had a mistake in drilling one hole in a header of a harp (hrsg boiler).
we want to build up the wrong hole by welding and again drill another hole in proximity of repaired area.
Is it permitted or prohibited according to ASME SecI or any other technical codes?
If it is permitted , is there any usual procedure for repair and test of this hole.
OD of hole is 35mm and thickness of pipe is about 34mm.
design pressure of the header is 157 bar.
pipe material is A335-P22

 

[metengr]

Yes, you can plug weld the hole and re-drill. Just make aure that you document this activity as a nonconformance in accordance with your Quality system manual, and your AI is involved.

 

[jbeckhou]

You will need to produce a WPS for welding a hole. A good reference is API-6A Hole procedure.

Petrotrim Services

 

[Duwe6]

Respectfully disagree on needing a new WPS. Your full-penn WPS will meet the Code requirements, assuming it is not limited in joint geometry. If it is limited, that WPS can be revised to include this welding.

Biggest issue it that you write the NonConformance Report, and get your AI involved with this repair. Do this first, as the AI's opinion on your WPS is the only one that matters.

 

[GenB]

"weld buildup" I would use a piece, prepare it for welding,
WPS? may or may not use same WPS ; full penetration is required with little or no reinforcing; test per your procedure and AI requirement as you may be required to UT the final weld. but 1.1/2" or 35mm opening is not a big sin...
Tube welding to header WPS may not be appropriate for the patch
but it could be okay,