asme ix QW-410.9 in multiprocess

[261073eam]

Hello,

I have qualified a PQR (P8 and T=10 mm) welded by GTAW (3 mm deposited by one pass) and SMAW (7 mm by 3 passes) process with CVN requirements. Then, it is possible to weld a test coupon of 3 mm by one pass only with GTAW process?

I mean, the QW-410.9 Multi to single pass/side take into account a pass by each technique or the total passes made by different techniques?.

Thanks in advanced

 

[DVWE]

You pose an interesting question for sure. Without a doubt, your original PQR is considered multiple pass, regardless of different welding processes.

One thing to keep in mind is your minimum qualified thickness, per QW-403.6. Because you have qualified with impact testing, your minimum allowed base metal thickness (T) is 10mm as per your PQR, so you really can't weld on a T = 3mm unless you are doing a separate PQR.

Technically QW-410.9 is applicable in your situation. However, I know that the purpose of multiple pass is the tempering effect of stacking weld beads (i.e. top weld bead tempers the weld bead below it as it is being deposited). And as this is a P-No. 8, perhaps someone with a little more knowledge of tempering those applicable in that P-No. group can chime in.

 

[261073eam]

I am sorry, the exactly question is this:

I have qualified a PQR (P8 and T=5,5 mm) welded by GTAW (t=4 mm deposited by TWO pass) and SMAW (t=1,5 mm by one pass) with CVN requirements. Then:

- It is possible to weld a test coupon of 3 mm by one pass only with SMAW process?

- QW-410.9 must be applied in case of each welding process or "multiple pass per side" includes GTAW pass and SMAW pass processes.

 

[DVWE]

It is possible to weld a test coupon of 3 mm by one pass only with SMAW process?

When you mention "test coupon" what do you mean? Are you doing another separate PQR?

QW-410.9 must be applied in case of each welding process or "multiple pass per side" includes GTAW pass and SMAW pass processes.

Includes GTAW pass and SMAW pass processes.

 

[261073eam]

I mean 3 mm plate to construction proposes.

Therefore, you are saying that multipass per side is independ of the welding technique used during PQR qualification. I thought that the esential/suplementary variables apply for each technique.

Thanks

 

[DVWE]

Therefore, you are saying that multipass per side is independ of the welding technique used during PQR qualification.

Yes. Your PQR is considered multiple pass, no matter how many different welding processes you used.

I thought that the esential/suplementary variables apply for each technique.

That is also true, but this supplementary variable applies to both welding processes in the same manner.