WPS Selection for Dissimilar Base Metal Thicknesses

[weeeds]

Is anyone aware of a list or schedule of weld joint configurations showing dissimilar base metal thicknesses, such as shown in ASME VIII Div I Fig. UW-13.2, that specifies the required base metal thickness range to be qualified?
We are trying to clear up some issues with respect to selecting the correct procedure for welding corner joints in P1-P1, P1-P1 with impacts, P8-P8, and P8-P8 with impacts.
Thank you

 

[metengr]

No, but if you find such a document let us know.

 

[weeeds]

If metengr does not have an answer to this question then I believe we have a serious problem.
Some welding specialists I spoke to have "their understanding", or "their opinion" but it just does not make sense to me that this issue is not clearly specified in the Code.
Attached is the only documented information I have been able to come up with but, I believe, it does not address the application where impacts are required.
A question this fundamental must have a well defined answer.
Yes? No?

 

[HgTX]

In AWS D1.5, it's the thickness of the weld, not the thickness of the base metal, that's qualified. (Preheat depends on base metal thickness.)

So a butt weld between pieces of different thickness would be considered to be the thickness of the thinner piece. For a corner joint, I guess you'd have to look at the depth of the groove throat.

Perhaps ASME has a similar philosophy.

Hg

Eng-Tips policies: faq731-376

 

[metengr]

ASME B&PV Code book sections (I, VIII) use nominal thickness for weld joints. Obviously, the nominal thickness definition must be reviewed and followed in the Code book. This is why there are no comprehensive tables for weld procedure qualification related to base metal thickness and specific materials.

You can develop your own spreadsheet based on base material and weld metal thicknesses limits and using exemptions for impact qualification. However, as I mentioned above, if you find such a comprehensive table let me know, as well.

 

[weeeds]

metengr
Do you agree that there is too much room for interpretation in the proper selection of the controlling base metal thickness, or are you of the opinion that the information to make the decisions is there clearly in Sect. VIII Div. I and Sect. IX and just has to be extracted?

 

[metengr]

or are you of the opinion that the information to make the decisions is there clearly in Sect. VIII Div. I and Sect. IX and just has to be extracted?

I would not say clearly, but the information is there in Section VIII, Div 1 to be extracted and applied.