ASME QW 200.4 (a)

Date 10-16-2008 02:18

If I understand correctly, the PQR with flux-coated rod was performed on a 0.240" thick coupon. This qualifies a range of 1/16" to 0.480" base metal thickness. The deposited weld metal thickness qualified for the flux-coated rod would be 2 times the actual thickness for that portion recorded in the PQR. The other 3 PQR's qualify a base metal thickness range of 1/16" to 0.960" with solid wire. However, the flux-coated rod is an unclassified filler metal since the AWS/SFA specifications only address bare wire. The last paragraph in QW-200.4(a) says:

"When following a WPS that has more than one welding
process, filler metal, or set of variables, each process,
filler metal, or set of variables may be used individually
or in different combinations, provided
(1) the essential, nonessential, and required supplementary
essential variables associated with the process,
filler metal, or set of variables are applied
(2) the base metal and deposited weld metal thickness
limits of QW-451 for each process, filler metal, or
set of variables are applied."

(2) says the qualified base metal thickness must be applied to each "filler metal", which is unclassified for flux-coated rod vs. classified under AWS for the bare wire. I believe you are limited to a maximum qualified base metal thickness of 0.480" for the use of flux-coated rod root passes. If a PQR were run on material at least 1/2" thick, QW-200(b) would allow the PQR to be used to support flux-coated rod root passes on thicker materials.

By canuckweld Date 10-16-2008 10:05

The flux cored rod is certified under A5.22 as R308LT1-5 and is considered an F6. I guess the question should be "Is the Thickness of the base metal and the thickness of the weld deposit are a requirement before you can join WPS's?". The thickness of the root pass with the Flux Cored rod on the PQR was 0.100". I need to weld an 8" sch 100 (0.594" wall) pipe using the flux cored rod for the root as this is a closure weld that can not be purged. I want to use the 1st procedure that allows me to fill out to 0.480" and then apply the 2nd procedure that allows me to weld out to 0.960".
Am I allowed to do this under QW 200.4 (a)??

By MBSims

Date 10-16-2008 22:30

My bad - you typed "flux-cored" and I had "flux-coated" on my brain from a similar question. I still believe the answer is no based on the last paragraph in QW-200.4(a).

By pipewelder_1999 (****)

Date 10-16-2008 13:18

Her is the response to a similar(identical) question in another forum.

Here is a modification of your statement without reference to the filler metal product form.

I have a WPS that is qulaified for 0.120" to 0.480" using GTAW . I have another WPS that was welded with GTAW for the full thickness with a range of 0.074" to 0.864" Can I use the 2 WPS in a joint on 8" 0.594" wall.

If you combine WPS's they must be qualified for the joint. There are allowances for combinatins of procedures in QW 200.4(b) however that exception is allowed in situations in which the PQR was for material 1/2" thick or greater.

I may be missing something but that is how I see it.

Gerald
www.weldingdata.com

By Fahmee Date 10-19-2008 04:18

Hi Canukweld,

My opinion is you can use existing 2 WPS ( root by Flux core TIG + fill by solid). your 1st WPS cover on root ( using flux core filler) and 2nd WPS has cover up to 0.864". but you have to create new WPS by combining the 2 PQR to support it. not require to requalify.

By MBSims

Date 10-19-2008 13:59

I don't see how you can combine two procedures welded with a different set of variables to increase the thickness range. Please explain how this meets QW-200.4.