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AC TIG welding of steel

SShep71

Cast Iron
Joined
Sep 17, 2014
Location
San Diego, Ca
BEFORE YOU POST: I have a pretty good understanding of welding, I have been welding for long enough now, I understand that steel and other ferrous and non-ferrous (stainless,inco,etc) materials are commonly welded with DC TIG. In order to save the arguments that are likely to follow please consider this before posting the expected "EVERONE KNOWS THAT STEEL IS WELDED WITH DC", "AC IS FOR ALUMINUM ONLY", "AC DOES NOT WORK FOR STEEL", "WHY WASTE YOUR TIME WITH STEEL AC"...etc etc etc.


I am trying to find a research paper that was released years ago about using highly unbalanced AC waveform to improve welding steel with TIG. I remember reading it and I had it bookmarked, however I lost a lot when my computer got totaled. The paper went into the specific wave form used and the parameters that were used during the process as well as the gas wire and all the pertinent info. I know there were a few companies that were looking into using AC TIG for steel but the resultant info was kept under wraps. I was hoping that someone on here may remember the paper or article as well and may be able to help find it. Thanks again for the help, PLEASE try not to turn this into a blood bath.

I know that there are other forums and websites, but there seem to be exceptionally large EGOs on some other more dominant welding websites, and GOD FORBID that one offend the welding "GODS" out there. It is unfortunate as the forums have become a waste of time because of that, let's not do that here. I just need help sourcing the relevant info.
 

DrHook

Cast Iron
Joined
Oct 8, 2013
Location
Pierre
No clue, here, but I'd like to read it, as I have "experimented" "by accident" in my own shop, and know it can be done, albeit not well...:D
 

DDoug

Diamond
Joined
Oct 18, 2005
Location
NW Pa
BEFORE YOU POST: I have a pretty good understanding of welding, I have been welding for long enough now, I understand that steel and other ferrous and non-ferrous (stainless,inco,etc) materials are commonly welded with DC TIG. In order to save the arguments that are likely to follow please consider this before posting the expected "EVERONE KNOWS THAT STEEL IS WELDED WITH DC", "AC IS FOR ALUMINUM ONLY", "AC DOES NOT WORK FOR STEEL", "WHY WASTE YOUR TIME WITH STEEL AC"...etc etc etc.


I am trying to find a research paper that was released years ago about using highly unbalanced AC waveform to improve welding steel with TIG. I remember reading it and I had it bookmarked, however I lost a lot when my computer got totaled. The paper went into the specific wave form used and the parameters that were used during the process as well as the gas wire and all the pertinent info. I know there were a few companies that were looking into using AC TIG for steel but the resultant info was kept under wraps. I was hoping that someone on here may remember the paper or article as well and may be able to help find it. Thanks again for the help, PLEASE try not to turn this into a blood bath.

I know that there are other forums and websites, but there seem to be exceptionally large EGOs on some other more dominant welding websites, and GOD FORBID that one offend the welding "GODS" out there. It is unfortunate as the forums have become a waste of time because of that, let's not do that here. I just need help sourcing the relevant info.

No arrows slung from here.

Did you try weldreality.com ?

Many people use A.C. on steel. I like 7014 rod on A.C. no arc blow, lights off like on D.C.

TIG with sq. wave and balance control offset, sounds like a good idea even on steel.
 

akjeff

Aluminum
Joined
Nov 17, 2008
Location
AK
Have used AC TIG to braze cast iron/steel, but have never tried it to weld steel. Interesting. No flames from me on this.
 

jermfab

Cast Iron
Joined
Jul 25, 2013
Location
atlanta, ga
I’ve known several “old-timers” who used balanced AC tig welding for light gauge stainless steel. I met them in an architectural sheet metal shop I was working in. They both claimed the AC waveform helped keep some heat out of the material and keep critical, thin pieces from tacoing. I remember on of the guys welding sink-mounting clips to the underside of a finished stainless steel countertop with AC. It was one of those mistakes that could have been costly if the finished side of the counter required lots of finishing rework, the old-timer wasn’t concerned at all. He knew he wasn’t gonna burn through or sugar the backside. I think pulsed TIG has kinda taken over from using AC for that kind of work though.

I’ve also known a couple purported aircraft welders who claimed the only way to weld aluminum was DC negative. They were quick to tell you it HAD to be done in an inert environment and only with the absolute cleanest possible material. These were also the only guys I’ve ever met who could claim TIME with the old Miller Aerowave machines. It’s totally possible they were just blowing smoke up a young kids ass as well.



Be safe




Jeremy
 

Scottl

Diamond
Joined
Nov 3, 2013
Location
Eastern Massachusetts, USA
Hmmm, "highly unbalanced AC" sounds like DC with some opposite polarity spikes so it probably could be described as "enhanced DC". If someone finds the paper I'd also like to read it.
 

GregSY

Diamond
Joined
Jan 1, 2005
Location
Houston
I can honestly say my TIG welds look no different whether I use AC or DC. On this turbo manifold, I used both methods and I will be interested to see if anyone can even tell.weld.jpg
 

pavt

Stainless
Joined
Jun 30, 2013
Location
20 miles north of Buffalo NY
I wish I could see the article you are looking for. I've been welding long enough (since 1992) for a living, as well as some machining. Had formal training in both areas. No reason why you couldn't do Ac TIG on steel, I've done it just fine. Tends to eat up a bit more tungsten is all. Sometimes works real good on sheet metal.
 

DDoug

Diamond
Joined
Oct 18, 2005
Location
NW Pa
Hmmm, "highly unbalanced AC" sounds like DC with some opposite polarity spikes so it probably could be described as "enhanced DC". If someone finds the paper I'd also like to read it.

It's the balance control, also called "cleaning" it applies d.c. to offset the square wave a.c.
 

joebass

Aluminum
Joined
Apr 3, 2005
Location
NY
I dont know about a research paper but there was a user on the miller motorsports page back almost 20 years ago? I think his name was "Hawk". He was the Dynasty Guru back then when most had Syncrowaves. That was before any of the major forums were up. Just Hobart I think. Anyway, I seem to recall him playing around and doing non critical work with AC. Check it out maybe?
 

Cyclotronguy

Stainless
Joined
Sep 21, 2005
Location
Northern California
Maybe I am confabulating, but I belive I saw the same TM. Thirty years ago or more, I was welding pressure and high vacuum appratus, and the shop had an Airco AC tig machine that was the size of a domestic refrigerator and I belive 400A AC Miller was I belive the actual maker of the machine and it's manual referenced putting a DC bias on the output for special GTAW applicaitons.

For heavy copper and some high chrome alloys they would bias up that machindes output with a bank of group 8D tractor batteries
 

kenton

Hot Rolled
Joined
Dec 15, 2015
If you have a near by engineering college you might try visiting the library and asking the librarians for help finding the paper.
 

SShep71

Cast Iron
Joined
Sep 17, 2014
Location
San Diego, Ca
I will post the paper if I ever find it, I sent an email out to the welding schools I went to and to the AWS and AISC contacts to see if there is any headway there. If I cannot find anything I will have to create my own research and I will be sure to post the outcomes up on here. As far as my specific requirement for the weld, well. . . that is still under wraps as I do not know yet if I should/can go over what I am doing.

@jermfab: I weld thick sections of Al with a 45deg bevel on DCEN then after a good cleaning I go back and do a top pass on AC to fill out whatever bevel is open and to improve the appearance. I have heard from more than one seasoned welder that AC TIG on steel with a properly balanced (or unbalanced depending on how you look at it) setup is amazing as far as the heat affected zone, the penetration, puddle control, things like that. It doesn't just work with the standard TIG setup as the ability to control the DCEN and DCEP independently was purportedly the key. I have an Aerowave at my shop, it is my favorite welder by far, I have a Dynasty 200DX as well but the Aerowave just has the power and the duty cycle. I have welded with a Dynasty 350 and a Dynasty 700 as well, apples to apples they are comparable.

@GregSY: The only thing that I can tell from that picture is that the original fabricator needs to consider a new hobby, perhaps ceramics or pottery.

@alphonso: There is no need to "bite your tongue". If you have relevant info or questions than ask away. The one thing I wanted to avoid was a whole bunch of the same illegitimate responses that do nothing but detract from the original post's intent.

@pavt: I as well do not see any reason that AC TIG has any issues, I was just looking for the paper that went into the specifics. There is no real reason to spend the time and energy redoing what was covered in the paper just to find out the results didn't produce the advantages I am looking for.


@Cyclotronguy: That sounds like some serious bias with that many batteries on one side of the waveform, it would be interesting to see the affect that much has on a weld. I would think that the unbalance would actually start to affect the electromagnetic field lines and begin to distort the TIG arc. If you have never welded right next to a strong magnet before give it a try, the affects of the field lines on the TIG arc are pretty sweet.

@kenton: I thought about that but everything is online now anyway, all the research papers are available to download through the schools online library. There are some older publications that have not yet made their way over as of yet, but it is being worked on. I will look into it to cover my basis anyway and get back to everyone.
 

DDoug

Diamond
Joined
Oct 18, 2005
Location
NW Pa
There are many technical papers that will never be on the 'net.
That's why I scrounge up all I can when I find them.
 








 
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