Low Thermal Input MIG Welding???

[qcrobert]

Good afternoon Gents,
What a wonderful, invaluable forum this is that we can draw on the knowledge and experience of such a vast audience of forum members.

I am investigating GMAW process equipment that will exert the least amount of thermal input into welding a .750" thk rolled CS flange to a .375" thk SS plate.

I have limited experience with Pulse Arc and was disappointed with the results in that heat input was still to high for my desires.

Although on the expensive end, the Fronius Cold Metal Transfer MIG welding process seems ideal and may be contacting such for a demonstration at our facility.

Would like to query all as to their experience and comments on this or any other MIG welding process that could produce the results I desire.

Thanks in advance

 

[unclesyd]

You need to take a look at this relatively new process. we are currently using it to weld 2205 Duplex SS. It fast and the heat input is definately lower. This process is actually a variant of the older hot wire TIG process. Welders don't seem to any trouble picking up on it.

 

[stanweld]

It was commonplace to make this weld with the short arc transfer mode during the 1960's and 1970's. Welders needed to be qualified on 3/8" wall with side bends.

 

[qcrobert]

Yes I am familiar with TIG Tip and Ed Craig. Unless the TIG Tip was pulse it wouldn't be low enough heat input for this project.

We do use pulse arc GTAW on many other projects where thin stainless steel is welded and concern for warpage is involved.

Needing high desposition fillet welds with practically no heat as the tolerances we are dealing with are .004".

Will report back on the CMT process after demonstration.

Thanks again for your input.
Robert

 

[TVP]

Robert,

Based on your comments, I agree that you need to investigate CMT from Fronius.

 

[Guest102023]

Is distortion the concern here? Is it a fillet or groove weld?

I believe the Fronius equipment referenced is similar to Lincoln STT and Miller RMD, which are advanced short-arc machines.

I suggest you qualify a GMAW process (regular spray or pulsed) or even FCAW (more user-friendly) and claim the added penetration. This will permit a smaller fillet size, and is the most effective technique to reducing heat input. This would require a qualification test.

 

[kingnero]

Depending on the application, MIG-Brazing might be worth considering, especially since it's an CS/SS connection.