Is pressure retaining fillet weld qualification by fillet weld possible under ASME IX.

[Vecho]

I work as QA in energy industry and run into a problem under ASME IX.

Scenario:

• Supplier has fillet weld PQR and want to set the qualification range of correspondent WPS into all fillet sizes on all base metal thicknesses and all diameters. I am deciding its approval.

To be specific, the PQR has 2mm thickness of base metal 1 and 4 mm thickness of base metal 2.

The WPS would be applied to 1.5mm thickness of base metal.

• The above PQR has 3 pass for one side but the WPS would has only 1 pass for one side.

To be specific, the PQR has root, fill and face pass.

The process is GTAW for 304.





In QW-202.2(c) Qualification for Fillet Welds.

WPS qualification for fillet welds may be made on groove ‐ weld test coupons using test specimens specified in (a) or (b). Fillet ‐ weld procedures so qualified may be used for welding all thicknesses of base metal for all sizes of fillet welds, and all diameters of pipe or tube in accordance with TableQW-451.4.

This is qualification by groove weld, so ti is not what I am looking for.

Nonpressure retaining fillet welds, as defined in other Sections of the Code, may as an alternate be qualified with fillet welds only. Tests shall be made in accordance with QW-180. Limits of qualification shall be inaccordance with Table QW-451.3.

This is qualification for Nonpressure retaining fillet welds.

And the paragraph end here.
From my understanding, it is possible to qualify pressure retaining fillet weld by fillet weld. QW-202.2(c) do not mention it because it is so obvious. Right?
And we should do it according to QW-180 FILLET-WELD TESTS.



My second guess is Limits of qualification, from fillet weld to pressure retaining fillet weld, shall be in accordance with Table QW-451.3. So it is for all fillet sizes on all base metal thicknesses and all diameters, from Table QW-451.3.



My third guess is the this PQR, which has 3 pass, need additional test for its apply to WPS, which has only one pass.

According to Table QW-256 Welding Variables Procedure Specifications (WPS) — Gas Tungsten-Arc Welding (GTAW).

Multi to single pass per side is Supplementary Essential.

QW-410.9 A change from multipass per side to single pass per side. This variable does not apply when a WPS is qualified with a PWHT above the upper transformation temperature or when an austenitic or P-No. 10H material is solution annealed after welding.

4th Guess: This is a socket fillet weld on pipe. Is socket fillet weld considered nonpressure retaining fillet welds?



Edit: There is a similar topic on fillet weld qualified by fillet weld in this forum, but I kind of not convinced by the reply.
Here is the reply and the link

the applicable paragraph of ASME IX is QW-202.2 (c) Qualification for Fillet Welds. The first sentence states “WPS qualification for fillet welds may be made on groove‐weld test coupons using test specimens specified in (a) or (b).” In this sentence the key word “may” is used, which implies that is a recommendation only (if you stop reading the paragraph).

But one of the main rules for the use of ASME BPVC is the reading of the whole paragraph. The penultimate sentence of QW-202.2 (c) is: “Nonpressure‐retaining fillet welds, as defined in other Sections of the Code, may as an alternate be qualified with fillet welds only”. And the inverse conclusion of this sentence is pressure‐retaining fillet welds must be qualified by groove‐weld test coupons.

https://www.eng-tips.com/threads/asme-ix-pqr-fillet-weld-for-pressure-parts.420631/

Gowelding has similar statement.

Fillet Welds: All weld sizes and parent metal thickness approved QW451.3
Note Fillet welds must be approved by a groove weld for pressure retention

http://www.gowelding.com/wp/calc3.htm