GMAW WPS on 1/2" Plate

By hevydoti432 Date 12-05-2018 15:28

Hello everyone,

Looking qualified base metal and weld metal deposit for a weld procedure for maximum efficiency. The base metals have been welded together and bend test and tensile test done and have passed.

Background:
ASME section IX 2017 edition
GMAW short cir.
.035 wire
1/2" Plate SA-516-70
no pass greater than 1/2"
no PWHT required
Single V-groove, 1/8" gap.

What is the maximum thickness qualified 1.1 times the thickness or 2 times the thickness.

Table QW-451.1 (note 1) and (note 2) refers me to QW-403.10 for base metal and QW-404.32 for weld metal deposit which both refer me back to Table QW-451.1 (note 1) and (note 2). It's a never ending cycle.

My question is at what point are the notes disregarded and just go with the table? Or would it be the 1.1 times the thickness for short arc transfer?

Thanks

By TimGary (****)

Date 12-05-2018 20:52

Just saying....

If you're really trying for maximum efficiency, you should not be short circuiting with .035 wire on 1/2" plate...
That is the opposite of GMAW max efficiency.

Tim

By Lawrence (*****)

Date 12-06-2018 13:54

Agree with Tim

I know.... You didn't ask for criticism.

While GMAW short circuit can be done in compliance on base metals that thick (you have proven it with the PQR) Doing it out in production, with all the vagaries of fit-up, technique, position, and access may prove to be much more difficult to harvest the quality I know you want.

The alternatives available with wave form controlled processes (both short circuiting, spray, and hybrid) are both more productive and typically able to achieve higher quality with less effort and skill level.

By hevydoti432 Date 12-06-2018 19:00

I agree as well, but when the higher ups are dead set on something because of what resources are available. What can you do besides showing them what's in the pudding.

By Shane Feder (****)

Date 12-23-2018 12:37

Who do you think will take the fall if these "inappropriate" welds fail in service ?
The "higher-ups" will be nowhere to be seen.
Up to you !

By Jim Hughes (***)

Date 01-03-2019 14:16

hevydoti432,
It does not look like anyone answered your question about 1.1 vs 2. For Short Circuit mode, it is 1.1 for deposited weld metal and material, if its less than 1/2". 1/2" and over its 2T,2t, per Tables QW-451.1 or QW-451.2. It does not matter if your using standard Short Circuit or a wave form technology like STT or RMD. Now, I have a question for you. Are you using GMAW Short Circuit for the root pass only? The company I work for is using RMD for plate work for the root pass with some very good success. Let me be clear, for root passes only. I think RMD is better than STT because it seems to handle poor fit-ups better than STT and the equipment is more versatile.