Argon gauge questions/ball type flow meter

[Longlasting]

I am using a quick connect to connect and disconnect the argon from the air line on my multi function machine and I am using the ball type flow gauge it came with; my mig has the twin head flow gauge and when I stop welding and shut the tank off the mig gauge stays at 15 cfh where I have it set, and the first gauge off the tank show the high pressure but on the tigs argon gauge/ball flow gauge when I stop welding, and shut the tank off the gauge pressure bleeds right down to nothing at the tank, the high pressure gauge which to me would indicate a leak somewhere in the machine, all my fittings are teflon taped into place and clamped with two clamps, and I took soapy water to check for leaks.
It stands to reason that the ball gauge would not move when the flow is stopped, but the gauge off the tank should remain at the pressure reading when the tank is shut off and machine is not in use as my mig does with the other type flow gauge.
Anyone else have experiences or can verify how ball type flow gauge should work?

[performance]

There is always a little leak that usually happens but usually, you don't have much. It is also possible that a little argon is leaking past the solenoid on the unit. But if its imperceptible while the unit is on, you are not loosing a significant amount if the ball is not flowing. Its possible that the tank you had had some dirt in the throat of the valve and when you pressurized the line, it blew it down into the solenoid. This type of thing happens quite commonly. I always give my tanks a couple of quick "blasts" to clear the throat and then carefully wipe out any residue inside that is left over.

Proper protocol for operating any unit is to bleed the pressure off anyway so that the parts are not under pressure for safety reasons, especially regulators. Just the other day a guy lost his life from not discharging his regulators when the regulator exploded from being under constant pressure.

Slowly open the valve,

[jakeru]

The flow meter has an over pressure relief vent, which you should check with some soapy water or leak testing fluid to see if there is any argon escaping out of it when the argon bottle is open. It's usually below the main regulator body of the flowmeter. I have circled it in the picture below of the Everlast unit.

A properly functioning flowmeter / regulator should not have any leaks out of its over pressure relief port. I have experienced issues with my everlast flowmeters leaking out gas here. To Everlast's credit, they have sent me a replacement flowmeter free of charge, however unfortunately it too had the same problem as my first one, so it may be a common problem.

After some disassembly and troubleshooting, I believe the root cause is not a faulty over pressure relief valve (which seems to be functioning as intended, and not allowing the regulator to explode...), but rather a faulty main pressure regulating needle valve seat, which when closed, does not completely seal and shut off the high pressure argon from inside the tank. It seems a tiny amount of gas can get past it...

I was only able to resolve the issue by going to a different brand of flowmeter.

[Longlasting]

Well what I did was remove the cover and take some soapy water and pressurized the line with air to 110psi, and I found a very large leak at the solenoid and a loose nut at the pressure gauge.So I removed the solenoid took some epoxy similar to the stuff the factory uses and removed the red gaskets all together and epoxied(JBweld) the elbow back onto the solenoid, then cut the hose clamp off the solenoid and replaced it with a permannent clamps from a welders kit.I am very happy with the results, it holds the argon pressure at the tank very well.But after about 4 hours it does bleed down,it holds pressure but does bleed down.I do not use hose clamps but permanent type clamps and after testing my own connections they are all good. So I suspect the solenoid may be leaking ever so slightly.Does anyone know what the seal is at the solenoid?Can it be replaced with new seal.If I recall all these welder solenoids are all simliar to domestics, and it would not be hard getting a name brand replacement solenoid if I had to.I am just worried about leaving or forgetting it after a weekend and loosing 25 litres of argon.Or can the solenoid be disassembled and sealed?What is used in the solenoid action? rubber seals?I know the fibre seals were the oxyacetylene type replacement for on the solenoid, so they were used for a reason-regs?I am impressed by how user freindly this stuff is to easy repair.

[performance]

In reality,

4 hours is almost no leakage.

I have other brand machines that will not hold that long.

All regulator's should be depressurized as it is. No pressure should be left on the line after shut down due to possible regulatator failures. This is standard safe operating procedure and not a "remedy" devised for your problem.

I have forgotten before myself, but after loosing a few hundred pounds tank pressure, you won't repeat the mistake.

[Longlasting]

No it is not bad right now in fact it is liveable, on my mig I shut down the gas and leave it I don't bleed the mixed gas, and you think this would be the same.One would think if I can get the T/A mig to have such a good seal i could match it with this one.I can tell now the air regulator requlires several tries when setting plasma air because their is no bleed off.
But will likely still pursue at some point when I have more time a better seal.I stopped welding when I noticed the leak.Good to be able to get back at it.
Thanks for the help.

[performance]

The JB was really unnecessary as Teflon tape works great for a sealant. Use that and you won't have any leaks if you do now.

However, I am not referring to only bleeding off our regulators. You should bleed off ALL regulators.

[Longlasting]

Actually this is the first I have heard of regualtor failure from not bleeding off the regulator, when I was in trade school in the 80's I remember being taught to bleed off oxyacetylene lines as a safety precaution to eliminate fuel and o2 but never heard of regulator failure of inert gases back then tig was heliarc and mig was well mig.You would think the machine side would always have a lower pressure especially if you are bleeding down slowly however minute it may be, and the tank being shut off should stop any lose.The only reason I want to rectify the problem of leakage is because I have, I don't know how, forgotten to shut a tank supply valves, we all have and it is a sinking feeling, especially here in canada when I am not close to Lws, and it is good to know their is nominal lose if it ever happens.

[performance]

The reason the regulators are bled is that remaining under pressure for long periods of time lead to "creep" especially on acetylene cylinders. The applied pressure on the spring must be released or it gets weak if it is constantly applied. This can create dangerous overpressurization of lines and other components.

[worntorn]

I had a fairly fast leak develop in my multi-function machine. When the tank valve was shut the tank pressure gauge would bleed from 2000 to zero in about 10 seconds. It turned out that the problem was at the hose connection on the solenoid for the machine pressure gauge line.
The 70 psi air pressure used when plasma cutting had pushed the hose about 3/4 of the way off the barb fitting. After pushing the line back on and pinching the clamp fully shut, this joint was gas tight.

I still had a slow leak somewhere as evidenced by the pressure gauge bleeding down to zero in about 2 minutes. This leak was in the quick coupler. After spinning the quick coupler to a new positon while coupled onto the machine, the leak stopped. It now takes hours to bleed down when shut off, which I think is pretty typical of any system.

[Tralfaz]

I have a slightly different issue with the regulator that came with my multifunction unit.

When I open up the tank and regulator the flow meter will not stay up showing pressure to the welder. I'm showing pressure in the tank, and as I turn up flow from the regulator the ball might hop up briefly, but it will not stay at pressure. I have checked for leaks and see none. After the tank is turned off pressure is maintained on the meter from the tank no matter how open the regulator is.

So I'm guessing I have a bad regulator, but figured I would ask to be certain.

[performance]

A little physics application, will tell you the ball does not float unless there is air to continuously push it up. How can a ball float in a closed chamber no matter the pressure unless it is flowing under it pushing the ball upwards against gravity? This is not a pressure indicator, that is in the gauge, the floating ball is a flow indicator. When the unit is in use, it will float, unless the ball is stuck, but if it pops up and then goes back down when you turn it on, this is perfectly normal. If it doesn't float while you are welding, then your tungsten should be melting as well, since you have no flow. The ball should only float or descend when the gas solenoid opens on the welder after the signal from the foot pedal or the torch switch tells it to.

In other words, you meter sounds like its working fine.

[Ray]

Hey Tralfaz,

What Mark is saying might be confusing if your not familiar with this type of meter, the kind with 2 gauges that are most common with this class of welder, are not true flow meters but pressure gauges, they estimate the flow rate from the pressure applied.
So simply, the gauge on the Everlast meter is the pressure in your tank, the ball is the amount of gas flowing in liters per minute. The pressure at the outlet is a fixed pressure set by the internal regulator.
I don’t know which unit you have, but basically to set it.

Turn up the post flow on the welder.
Tap the trigger or pedal to start the flow of gas.
Set the meter so the ball floats between 5 -7 LPM. (with gas flowing)
Reset post flow knob to desired rate.
Weld away..

[Tralfaz]

OK. That all makes sense. I guess, to some extent, I knew it had to be measuring flow, not pressure, but being new to this, I wasn't sure how to really set the system. I'll do what you mentioned and see if I can get it set up correctly now.

As you said, I'm used to the pressure gauge on my mig, so I just wasn't quite up to speed with how a flow gauge works.

Tig is a bit of a different thing than the mig and oxy/acetylene I had mostly done to this point.

Thanks, Ray, for more details on how to work with this.