Steel mill terminology: "weld repair" - Do mills repair defects?

[just_some_shmuck]

I have a material certification report (for C-channel) and at the bottom, it states: "No weld repair was performed on this heat".

This makes me wonder: Do mills sometimes repair defects in structural shapes? Grind out the defect, fill it with weld, grind it smooth, and send it out the door?

 

[TugboatEng]

That's a good question. You're in the mill already, the defective beam doesn't have far to go to get remelted and recast. It would be hard to break even on the labor of repair and inspection vs recasting. Also, for continuous cast sections, I would expect the defect to be continuous as well which means there would be a lot of repair required.

 

[WKTaylor]

On non-heat treated parts... that are weldable... welding [same alloy filler] can be approved/used as to salvage-repair parts pre-HT with obvious defects... when approved.

Castings, forgings, plate, rolled, extruded shapes, etc may weld-repaired, when approved.

Regards, Wil Taylor
o Trust - But Verify!
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation, Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", HBA forum]
o Only fools and charlatans know everything and understand everything." -Anton Chekhov

 

[mrmalcolm]

Imperfections of a harmless nature, for example pitting, rolled-in scale, indentations, roll marks, scratches and grooves, regarded as being inherent of the manufacturing process, are permissible irrespective of their number, provided the maximum permissible limits of Class A of EN 10163-2, are not exceeded and the remaining plate or wide flat thickness remains within the average allowable minus thickness tolerance.
Total affected area with imperfection not exceeding the specified limits are not to exceed 15% of the total surface in question.
Affected areas with imperfections with a depth exceeding the limits of Class A of EN 10163-2, shall be repaired irrespective of their number.
Cracks, injurious surface flaws, shells (over lapping material with non-metallic inclusion), sand patches, laminations and sharp edged seams (elongated defects) visually evident on surface and/or edge of plate are considered defects, which would impair the end use of the product and which require rejection or repair, irrespective of their size and number.

 

[EdStainless]

If you read specs carefully you will find some that say weld repair must be reported, others say that if can only be done with prior approval, and some that don't mention it at all.
If the product requires NDT then it must pass the original NDT after the repair.
You can't use a different test.

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P.E. Metallurgy, consulting work welcomed

 

[JR97]

From the QA side, some specifications require a positive statement if no weld repairs were performed (similar to no mercury containing compounds were used during manufacturing). The mill probably chose to stick the statement on all the paper to avoid missing it on one that required it.

JR97

 

[Ng2020]

Agree... it's a " no animals were harmed in the making of this film" kind of statement.