Query on ASME IX SMYS

[wontweldcantweld]

Hello all,

I've reposted this from the materials and metallurgy forum as it's an ASME query.

This is for CRO (Corrosion Resistant Overlay) i.e. cladding of 8630 80KSI components.

Basically, I'm reviewing a welding procedure for a client, which they have welded two separate test pieces. It's the same material grade (8630, which I believe is unassigned under ASME) but one test piece is done on 80KSI (552 MPa), and the other on 75KSI (517 MPa).

They've both been combined into a single WPS welding procedure, which has got 80KSI on it. I've questioned it but been told that under ASME that SMYS is not an essential variable and therefore as it's the same 'grade' (despite being unassigned) this would be acceptable as its for overlay cladding, not a butt weld. Additionally, the PM and AWM tensile of the 70KSI have also come out at higher than 80KSI which is where I think this argument has come from.

I would say this wouldn't be qualified but can also see their argument. Is anyone aware of this being permitted under ASME or if it's a non-essential variable?

Thanks,
wontweldcantweld

 

[DVWE]

I’m curious if you are reviewing an overlay only WPS, or the joining (groove weld) of CRO parts?

For joining, yield strength has never been a requirement for Section IX qualifications. Only Tensile. See QW-150 and 153.

Also, tensile tests, bend tests, toughness tests, etc. are not considered “essential variables”. They are simply the required mechanical tests for WPS qualification.

The devil is in the details; she also wears prada.

 

[wontweldcantweld]

Hi DVWE,

Apologies, this is for CRO only, with Inconel 625.

The SMYS is that of the base material. For example, would a PQR which was CRO on 8630 75KSI material, be qualified to weld 80KSI material? Note that 8630 is unassigned, though seeing as its *technically* the same grade, would this change in base material SMYS constitute an essential variable?

Thank you,
wontweldcantweld

 

[DVWE]

For example, would a PQR which was CRO on 8630 75KSI material, be qualified to weld 80KSI material?

Yes, it would. Typically, there are three required tests to qualify a CRO WPS. Chemistry, liquid penetrant, and bend tests. Customers may require hardness testing or others. Tensile testing, including yield strength, is not required.

Note that 8630 is unassigned, though seeing as its *technically* the same grade, would this change in base material SMYS constitute an essential variable?

No, it will not. See QW-250 for the specific welding process used and the list of essential variables.

The devil is in the details; she also wears prada.