Argon regulator leak

[robsthomson]

Hi, after going to do some welding after a few months of not using my powertig welder (with the regulator left installed and the tank valve closed), I found that there is now a large leak at the argon regulator. At first I thought it might have been from around the tank valve stem, but it seems to be coming from the CGA fitting between the tank and regulator.

I've tried removing and reinstalling the regulator several times with no luck.

It seems like one or both of the fittings may have been damaged somehow, but both the tank and the regulator were securely chained to a steel column and not even touched during this time. I'm using the regulator that came with my powertig welder. I couldn't see anything visibly wrong with the fittings.

Is there anything I should try before I take the tank and regulator to a welding shop?

Mostly, I'd really like to know what might have happened to cause this and how I can prevent it from happening again.

[performance]

Overtightening can deform the mating faces or crack the nut. Or a particle of dirt left on the face from a mud wasp or something can scar up the faces. You should give a long blast of argon from the cylinder and wipe down the mating surfaces with a clean dry rag before you tighten them up.

To confirm the exact place of the leak, coat the regulator in a sudsy mixture of Dawn dish detergent and water. Liberally "paint" the areas and bubbles should form right around the area of the leak. This will help you pinpoint and possibly correct the source of the problem.

[robsthomson]

Well, I can confirm that the leak location is definitely the connector.

I should also say that by "bad leak", I mean that when I open the tank valve I get a blast of argon blowing on everything from around the connector thread, not just a loud hissing noise. Its about what I'd expect if the connector was just loosely screwed in and not tightened at all.

There doesn't seem to be any visible damage on the mating surfaces. The regulator side is as clean and smooth as when it came with the machine. The only thing notable about the tank side is a ring where the brass is discolored where the fittings press together, which I think was there when I bought the tank.

I've always wiped off the connectors and cracked the valve before attaching the regulator, so there shouldn't have been any dirt.

I don't think I've been over tightening them. I've generally tightened it either "very hand tight with gloves", or the same amount with a wrench. How much torque should I actually be using?

I'm also wondering if temperature change could have caused some damage. The last time I used the welder, it was winter and my unheated shop was very cold. Since then, it got fairly warm in the summer and it is now about room temperature. So, in the meantime, the tank and regulator have been through a temperature range of at least 80F.

[Wrenchtamer]

If those fittings were left tightened I would not be shocked if the regulator side of that connection was warped a little bit since the two dissimilar metals contract at different rates. I see this sometimes on a fitting between the high and low sides of a refrigerant system and although it has never been confirmed by the manufacturer, I believe that the difference in thermal characteristics has something to do with it.

[jakeru]

Has anyone had good luck with the "hand tight" versions of the CGA fittings? I'm talking about the tank fittings often found on helium balloon filling regulators that have a little rubber o-ring to make the seal, and a large plastic handle around the nut so you can just tighten the fitting with your hand.

The rubber o-ring seems like it would seal with a lot less pressure. I'm just wondering if anyone has tried it on an argon regulator, and if so, did you find that it worked well, were you pleased with it, etc.

PS - for the original poster, inspect the cylinder side of the fitting for knicks, dings, and any galling or scoring marks, and try to polish/clean it with a little scotch brite pad or steel wool. Similarly, you can inspect the regulator side of the fitting, and polish that mating surface as well. A smoother surface should seal more reliably with less force. Oh and also, make sure the CGA nut spins freely with low friction compared to the rest of the fitting. You don't want the fitting twisting at all when tightening the nut. If there is friction, identify it (dirty? galled surfaced?) and eliminate it. Any burrs can be filed down to reduce friction. I've also tried putting a dab of oil on the surfaces where the nut bears on the back of the fitting, and found it was helpful to make it tighten up much nicer. That may not be recommended however.

PPS - anyone know how much torque are we supposed to tighten the CGA nut to? I have been usually tightening mine down pretty hard, with a pretty big wrench.

[robsthomson]

Wow. I was wrong about the problem. The fitting wasn't the leak at all. The argon was just blowing across it a lot.

The regulator body had a hairline crack running between the gauge and cylinder ports. It was nearly invisible, but under pressure it would spread apart enough to let gas out. Thankfully it didn't explode.

My guess is that it was probably cracked before I got it and only spread enough to leak later.

Anyway, problem solved, I've ordered a new regulator.

[jakeru]

One of my Everlast flowmeters also had a hairline crack in the main regulator body, extending through the female threads of the main body where the CGA-580 nipple screws in, extending part way into the back of the body. I found it with leak test (soapy) fluid when I noticed small bubbles.

The replacement Everlast sent me (although free of charge and without ANY hassle) leaked argon out of the overpressure relief valve (located at bottom.) I think the overpressure valve was functioning properly. I think the main regulator seal was not holding back the high cylinder pressure completely. (Good thing the overpressure relief valve was going its job, it it could have exploded, I thought! ...Never try and disable an overpressure/safety relief valve!) Now I love my everlast TIG welding machine (Super200P) to death, but after two faulty everlast flowmeters, I was ready try something different.

I've had good luck with an HTP flowmeter. It looks good, well constructed, reads in standard flow units (CFH), and is pretty easy on price also. In fact I'm working on converting mine to a dual outlet (so I can back purge stainless welds).

[sschefer]

Harris (Lincoln) makes a decent dual. Runs about 250.00 but I suspect you're going to use a y or a t to put a second meter on it. Smith and Victor also make them.

[Paul Moir]

I had a nice Liquid Air regulator so I used that, and then teed in the everlast flowmeter for a back purge after the regulator. If the flowmeter part is fine then you could just do the same.

[SimpleSimon]

I just discovered a similar leak on my regulator. A hairline crack from the tank inlet port to the gauge.

[2rods]

Sounds like real high quality regulators Fing chinese junk. Glad i saw this as I was going to order one from Everlast. Not now.

[performance]

2rods,

I have several Everlast regulators, and never had one leak. In fact they have a quality feel to them. I have a Smith that is barely used and it creeps.

[trackmaster]

My reg works Fing F'antastic! Great feel, stays where i set it. Just like the rotisserie oven, ..... i set it and forget it!

Oh yeah that 250EX, ..... almost forgot about that, .... NOT! Still rockin! I love this machine. Not a glitch 6 months in. This is the real deal, and the 300 cooler? ..... unreal ..... what a great match. Serious Rig folks!
Thanx so much to the Everlast team! - Lou

[Ray]

Sounds like we have a few that had the inlet stub overtightened and split the regulator body, too much of a good thing.. Usualy not an issue.

[jas329]

I just discovered a similar leak on my regulator. A hairline crack from the tank inlet port to the gauge.

I have the same issue on mine, I finally got around getting the argon regular setup on my tank. I snugged up the connections, but making sure not to over tighten them, but when I slowly opened up the valve I heard it leaking quite a bit. I thought it might be the threads leaking but when I looked down on the body of the regulator I saw a hairline crack. At first I thought it was just the chrome finish but when I opened up the valve again I noticed the crack was opening up and I felt gas flowing out of it. I quickly closed the valve, worried it might explode on me. I pretty d@mn glad that I did a check before opening up that thing all the way.

I hope Everlast can help me out here, the regulator has never been used before, this is its first time on the tank. The regulator has always been kept indoors where its warm, so I don't think its temperature shock. What I can guess is that it was damaged in delivery because the box the regulator came in was pretty smashed up. I guess I should have looked more carefully but the unit itself seemed pretty stout, I didn't think that the heavy metal body would crack so easily. Initially when I got it I just made sure the plastic flow meter and pressure gauge wasn't damaged. I've included some pictures, sorry if they are hard to see, I ran out of batteries for my camera so I used my cell phone to take them.

image of crack from inlet to pressure gauge:


image of crack from pressure gauge and almost to flow meter:

[geezer]

You don't want to use or attach that regulator anymore, the potential for injury is too great. There is a lot of pressure in there and if it blows apart you could get really hurt. trash that thing and get a new one.

[jakeru]

Here is the crack on one of my everlast regulators, starting at the inlet nipple, extending towards the middle of the body's back side.

It took me a while before I noticed it and I only found it by accident. I was applying leak test fluid around the CGA-580 to argon tank connection, to try and find out where my expensive argon has was going. I got some leak test fluid actually by accident on the back of my regulator. "What the heck are these bubbles?"

I should say on this regulator, that I did have a "professional" regulator rebuild shop install the CGA-580 nipple. That is because the everlast regulator originally came with an incompatible CGA fitting, which would not attach to a standard argon bottle, as found in the USA. The shop did say something about not being happy how it went. Maybe they caused this crack, I don't know. But the regulator body does seem to have a thin spot / weakness where the crack is that I have shown. Be careful...

[2rods]

They are cheap junk plain and simple. You get what you pay for. Also using teflon tape is a no no as the threads are so lubricated with the tape that it never feels tight and one will tighten too much till it splits. Should always use teflon paste.

[jas329]

geezer: you're right its not worth the risk to keep that regulator attached, with 2000psi surging through it can go bad really quick. I shut the gas and took that thing right off after I found out where the gas was leaking from.

jakeru: looks like the shop might have installed the new nipple that was too big for the opening and caused it to expand and crack. Or another possibility was that they heated the nipple to try to remove it from the regulator which caused the metal to become brittle. But that is just my guess. If its cracked its best to replace.

[geezer]

These days you have to take the good with the bad, there is a big difference between brass made when I was a kid and todays' brass. Todays brass is mostly recycled brass (they say up to 90 % of all brass) and the copper zinc content can vary creating a more brittle brass subject to cracking. As far as the regulator goes, they are a good buy at the price, just don't over tighten them in certain areas where the guages etc. go in the body and like anything else give it a periodic inspection. The days of using virgin brass to make things is over. Everything is recycled these days.