What's new
What's new

Why do I keep getting bad argon?

Dave_C

Cast Iron
Joined
Sep 29, 2008
Location
KY USA
Two fill ups ago, I got a bad tank of argon. It was like I was trying to weld with CO2. After that, I shelled out and got a large tank to use as the main tank, keeping my smaller one as a backup.

Now I've got my (freshly filled as of Friday) large tank and the weld has an almost porous looking finish; like the weld itself has been shot blasted. When it welded, it looked like there was a very small amount of contamination in the weld pool; the type of contamination that you should really stop and clean, but nothing really to worry about - especially for the small jobs I'm doing for myself. Now it is possible that well, maybe I'm imagining this, and I'm just having a bad bay, but it's the same on all tungstens, and doesn't make a difference if I'm at 65 through to 75% cleaning, or if I go from 80 to 200Hz. There are only so many settings on a 200 DX after all. And yes, I'm on AC lol...

So I jump to my smaller tank (also filled Friday) that now acts as my backup when I run out of the large tank, and once again, it's like I'm welding with CO2- same as several fill-ups ago...

I am obviously going to go back to my supplier on Monday, but the last time I took a tank back, they acted all surprised like I was a freaking idiot, as no one else had complained. I'm almost at the point of asking for a refund and telling them where they can put their tanks, and going with Holsten gasses - who are actually closer to me...

I'll post some pics of these awful welds later, but I was curious if anyone else has had the 'shot blasted' weld appearance before, and just maybe, today, I'm doing something silly...
 
Forgot to say, I'm getting a lot of arc scatter as well - that's why I'm really thinking my large tank is contaminated. It's really, really difficult to do a lap and inside weld.
 
Two thoughts:
1. Switch to DC electrode negative and weld some clean stainless. If the weld turns out good then you can't point to the gas, the machine running on AC is the problem.

2. Check for a clogged gas connection.

3. If the problem is only on AC then a local dealer might have service tech that can visit your site. Some one came to my place and the problem was a clogged fitting. The service guy even refused my buying him a takeout sandwich and drink at the meeting. That was Miller service ten years ago.

4. Your statement "my tank" : it's not really your tank. You own it but when you get a refill the tank is exchanged for a supposedly clean and filled replacement, Right?
 
Just fishing, but you checked your equipment and hoses for leaks? You might be aspirating oxygen into the system from a bad connection. That would explain multiple bad Ar tanks.
 
4. Your statement "my tank" : it's not really your tank. You own it but when you get a refill the tank is exchanged for a supposedly clean and filled replacement, Right?

My Argon tank is my own, I've never exchanged it, never been asked too, always get it refilled, takes a little longer than an exchange
 
Been a more and more common theme... the extent some of the high end fab guys are running filter drier systems before their welder.

Right from the article...

"I am not sure why but it seems that the owner size cylinders are the culprits in most cases.

My theory is that owners cylinders just dont get as much attention as the leased cylinders."

Welding Gas Dryer
 
My Argon tank is my own, I've never exchanged it, never been asked too, always get it refilled, takes a little longer than an exchange

I own my tank too, but it's always exchanged for a properly cleaned and filled tank. I own the tank currently in my possession. That's how it has worked at two dealers that do filling off site and one dealer that has on site filling. Those three dealers claimed that exchange tanks are always cleaned first. If your refill is just a refill and nothing else then your assumption might be right. Ask them how they process your refill. Suggest that you do not get too attached to your cylinder.
 
I have had probably 6 different gas suppliers in the 45 years I have had my own shop and have never gotten a bad tank of any kind of gas. anytime I have had an issue it was always welding equipment.
 
I'm more confused than ever...

There is definitely is a difference between my two tanks of argon.
Even running Beads without any filler rod, The small tank leaves a thick layer of the white powder / dust all over the end of the cup. The other one does as well, but to a lesser degree. I've changed between the tanks forwards and backwards at least a half dozen times, and the smaller tank makes the cup white a lot more than the other ( which is something I've never really noticed before).
 
IMG_4549.jpgIMG_4547.jpgIMG_4550.jpgIMG_4552.jpg

First pic is the cup - you can see where I have wiped the powder away.
Second pic is of my tungsten. This is getting torn up in a way I've not seen before. The point is also disappearing (2% lanth).
Third pic is a trial plate. 1/16 6061. Working from right to left, the first bead is no filler rod, and cold tungsten, Second bead is no filler rod and hot tungsten (laid down immediately after the first bead), third is me trying my hardest to fight the arc and force a bead with 1/16 4043 filler... This is repeated (from bottom upwards) for the frequency and tank # as shown...
last picture is a close-up showing the weird coloration and apparent contamination at the start of the no-filler beads on the #2 tank (what seems to be the worse one)...

FYI This was welding 40 all-in and 70%.

I've tried two different packets of 4043, a tube of 5356 and some 4943, which I normally reserve for die castings or other more difficult welds as is hard to find and pricey...
I've tried welding 6061, and 3xxx, and even pulled some past welds out the scrap bin trying to weld a good as they were; all to no avail.

I welded some 304, and I've got a somewhat grey, hot looking weld - I can't even get the rainbow welds running a non- filler bead; something I've never had a problem with before.
 
IMG_4554.jpg

This is as good of a close-up that I can get with the I-phone, showing the shot- blasted finish of the weld.

I've tried at least three different suppliers-worth of gas lenses from both 1/16 and 3/32 - including some very well used ones that worked fine previously, but just looked ugly and beat up. I finally reverted to standard collets and cups, both in 1/16 and 3/32. No diffetence anywhere.

Please understand how annoying it is for me to be posting these welds onto on the Internet; I am capable of a hell of a lot better than this, hence my real frustration.

:-(
 
My mind went instantly the same place as Dave G
" You might be aspirating oxygen into the system from a bad connection. That would explain multiple bad Ar tanks."

I've had this happen myself and in my case it was leaking right up in the torch head. Nothing you would have noticed from the outside of the torch by just looking. There are of course many other places in the plumbing system from tank to torch. Got another torch to stick on and try?

I can give you another personal example of how sensitive aspirating is. When I bought a new Lincoln MP 350 mig welder last fall, before it even left the store, my salesman took the nozzle off the gun and looked to see if it had a silicone o-ring to seat against. Then proceeded to tell me he had sold several of those machines to a large fab shop and they were complaining of porosity in their welds. Turns out the original design of that gun did not have a o-ring provision and oxygen would (could?) aspirate at that point into the shielding gas stream. It doesn't take much.

I'm not saying you aren't getting some contaminated argon from your supplier, just throwing out some more encouragement to check over your equipment.

Keep us posted as to the outcome and best of luck. Hope you get to the bottom of it ASAP.
Gus
 
Can someone explain how if I have a leak in my sheilding gas line (which is on the greater pressure than the air around the line, that the air will get into the shielding gas line. I've got two smart guys suggesting this is the problem, so it's definitely worthy of investigation but I just don't understand how it can happen???
 
View attachment 201425

This is as good of a close-up that I can get with the I-phone, showing the shot- blasted finish of the weld.

I've tried at least three different suppliers-worth of gas lenses from both 1/16 and 3/32 - including some very well used ones that worked fine previously, but just looked ugly and beat up. I finally reverted to standard collets and cups, both in 1/16 and 3/32. No diffetence anywhere.

Please understand how annoying it is for me to be posting these welds onto on the Internet; I am capable of a hell of a lot better than this, hence my real frustration.

:-(

Are you sure your welding rig is working correctly? I would suggest to try a different welder with your gas.I bet there will be a difference.
 
Can someone explain how if I have a leak in my sheilding gas line (which is on the greater pressure than the air around the line, that the air will get into the shielding gas line. I've got two smart guys suggesting this is the problem, so it's definitely worthy of investigation but I just don't understand how it can happen???

The higher pressure fluid (Argon) passing by an orifice will syphon air into the flow.

Same principal as a syphon sprayer for garden chemicals or detergent syphon on a pressure washer. The most common syphon would probably be a paint spray gun.

Keep in mind that siphons work with both gasses and liquids or either combination.
 
Dave,
I may have a gross misunderstanding of this, but I think that is why Dave G. used the term aspirating, and it's also why I suggested perhaps looking at the torch end of your rig.
At the risk of insulting Mr. Bernoulli, it may be possible by the principles involved with the venturi effect(?). I know it seems counter intuitive, but the same problems happen on fuel injection plumbing, etc. Again, I could be all wet on this.
Here is a short youtube vid on the matter Fluid Dynamics VII: The Venturi Effect - YouTube

I'm as interested as you as to what is causing your problems, so we will hope someone more knowledgeable will chime in with other suggestions for you cure. I grew up around a crotchety old weldor who always claimed when he got to the 'bottom' of a bottle of argon, that it was no good, that all the impurities were down there. I always think of him when I'm sucking the last fumes out one and still getting good shielding.

Hang in there Dave, you'll get it figured out.
Gus
 
I'm more confused than ever...

There is definitely is a difference between my two tanks of argon.
Even running Beads without any filler rod, The small tank leaves a thick layer of the white powder / dust all over the end of the cup. The other one does as well, but to a lesser degree. I've changed between the tanks forwards and backwards at least a half dozen times, and the smaller tank makes the cup white a lot more than the other ( which is something I've never really noticed before).

What kind of flow meter do you have? Do you know what the tank pressures are?

Also, do not forget that the very act of changing the bottles is changing the physical characteristics of the weld gas system. The smaller bottle is likely shorter or something like that. So just because the smaller bottle welds differently, does not mean it is the gas that is different. Only the end result is different which means everything from the cup through the torch, hoses, gas solenoid, flow regulator, flow indicator sight glass if it has one, to o-rings in the sight glass can all be culprits.

The white powder is probably aluminum oxide which leads me to believe that air is being mixed into your gas stream.

I think that blaming your problem on bad gas is looking at probably the least likely possibility.

Gas suppliers are setup to deliver a consistently pure product to spec. There are a lot of specialty processes that require much greater consistency of the delivered welding gas than what you are needing for a good weld.

As most are telling you look at the welder gas system.
 
-soap check all connections from the regulator/bottle valve to machine, out to torch connections
-check actual gas flow out of torch cup with flow indicator
-if one's using any chinese torch consumables-trash 'em (they collapse/etc.)
-replace any collets showing any sign of bulging/swelling--even CK wedge collets do that-now,
which is disappointing.
-verify actual fit of cup to teflon insulator, back cap o-ring to torch body, verify that's what actually supposed to
be on said torch per mfg. ass'y. breakdown

--as others have mentioned, after that initial pressure 'burst' as solenoid opens the flow to the torch,
the flow down the hose, thru the fittings CAN and DOES pull in minute amounts of air for contamination.
Venturi effect/brownian movement--whatever---it happens, even if you can't get your head around this;
you're seeing the result.

--try new torch and leads or at least--replace back cap, cup, teflon insulator, collet, collet body with new

THINK....what consumables/etc. did you change out before encountering this?

[In 29 years I've had one bad Ar bottle---but prior to changing bottle--one verifies all these lettle, pesky details.
Fill plants are getting sloppier and sloppier in their filling. The same bad bottle order also came with a completely empty,
75/25 Ar/CO2 bottle--which I got charged full boat for.]
 








 
Back
Top