Gas regulator, problems or normal ?

[90blackcrx]

I'm hearing mixed things from different people so I would like to bring this up in a topic, recently I purchased a 200dx syncowave that came with a gas regulator.

As soon as I hooked up the regulator I noticed a horrible leak, look to picture, left of thumb.

http://i3.photobucket.com/albums/y72...rx/leak002.jpg

There was no way for me to tigthen that area, there is no nut around there. So I took everything off and checked to make sure everything seemed right. I found a piece of Teflon tape sticking out from where it was leaking, so I pulled it off and cleaned the area up.

I installed everything and from what I could hear there was no more leaks. But here is where I think there is a problem.

Every time I close my bottle the argon, the high side gauge will slowly go down until it reaches zero. Now I have heard this is normal, but I have also heard its not. So thats where I'm kind of confused.

I'm also having a problem with the low side gauge, its really hard to set. I turn the regulator knob and it takes a while for it to kick in, and when it does it usually kicks in a lot and shoots over the desired psi. So after I finally get it set to where I want it, I lay down a few beads and look at the low psi gauge and sure enough its not where I set it, its actually about 3psi lower.

So is this normal ? I know my Lincoln gauges act nothing like this.

[jolane]

I don't know about bleeding down, as this could simply be the valve or something else leaking on the bottle. Who knows, I would just check with bubbles myself and try to locate a leak.
As for the low pressure (flow measurement I assume is what you are talking about), you chould adjust that while flowing cas. I am not sure of the best way to set this other than strick and arc and adjust the gauge. Actually, if you can set you post flow for say 10 sec, just adjust it right after letting off the pedal. Don't worry aboutwhat the gauge says when the gas isn't flowing, only while it is.

I hope this helps,
Joshua

[Fishy Jim]

You don't need to strike an arc. Just hit the pedal and watch the gauge.

I don't think you should be getting any leak down if things are properly sealed. Maybe call Miller and see if they'll swap the regulator out under warranty.

[90blackcrx]

You don't need to strike an arc. Just hit the pedal and watch the gauge.

I don't think you should be getting any leak down if things are properly sealed. Maybe call Miller and see if they'll swap the regulator out under warranty.

I should of added, I closed the regulator all the way and the bottle still leaks down. Which means if there was a leak, its on the high side. I sprayed it with water and soap and could not find anything really. If the leak is on the bottom its going to be pretty hard since the water runs off. And I do adjust the regulator with the gas flowing, but its still droping down a few psi after I run a few beads. Its dropping down when no gas is flowing, but that would still mean its dropping when gas is flowing.

And since I'm new to welding I can't really say if its normal or not but, I have welded not even for an hour max, and I could already see that the high side gauge pressure went down. At this rate a 150cf bottle will last about 2 weeks, which don't seem normal. I just did not think I would see the high side gauge has any effect yet.

I will contact miller and see what they tell me. Anyone have an email address where I should contact them ? Going to look right now but to save me time I thought someone could help me out.

[unixadm]

I have two regulators and three flow meters presently. All connections are good and sealed. I still get leak down over the course of a few hours. That's on a MM 251, MM 350P and a Dynasty 200DX. I'm guessing the 300DX I get this week will be the same way. The only machine I have that does not leak down is my Passport.

[unixadm]

TIG consumes gas QUICKLY. It might say 15 CFH - but it goes quicker than you think. I'm actually switching to a gas saver setup to see if it will help. That combined with gas lense torch parts may help cut down on gas usage and waste.

Here are some pics of the reinforced / smaller ID gas lines. My buddy uses it with good results. Nothing huge, but every little bit helps over the course of a few years.

http://www.dmwtech.com/gallery2/v/welding/machines/gss/

[Fishy Jim]

On my mm130, I didn't close the valve for over 6 months and had no noticeable loss of pressure (forgot when I left it and didn't come back to it for half a year while I was away at college).

If you have a leak anywhere in the system up to the solenoid, it will lower the high side until you lose all the pressure above what the low side is set for. The only way you'll be measuring the high side leakdown is if you back off the diaphragm completely, and that still might not completely seal off the low side.

Also, like the man said, Tig uses up a lot of gas.

[own6volvos]

You need to remove that pipe and put fresh teflon tape on it. The "tip" that meets with the bottle should have a hex shape on the end that a socket wrench should fit over.

After turning off my gas tank, pressure usually drops around 50psi a day, and goes flat after a week. I am guessing the leak is the solenoid valve in the welder that isn't a super perfect seal.

[90blackcrx]

I was told never to use teflon tape. I understand if I do use it, not to load it on and just keep it on the threads. But putting it on the tip, is going to be tough because there is nothing for it to grip on cause there are no threads, so I really don't want to do that. I can put it back on the threads, but will I run a risk of it contimanting the welds ?

On my mm130, I didn't close the valve for over 6 months and had no noticeable loss of pressure (forgot when I left it and didn't come back to it for half a year while I was away at college).

If you have a leak anywhere in the system up to the solenoid, it will lower the high side until you lose all the pressure above what the low side is set for. The only way you'll be measuring the high side leakdown is if you back off the diaphragm completely, and that still might not completely seal off the low side.

Also, like the man said, Tig uses up a lot of gas.

So if I back off the regulator meaning no pressure was being let to the low side, low side gauge is at zero. And I close the bottle and the high side goes down, it would have to be on the high side right ?

Also I know tig used a lot of gas, but I already seen the high side pressure drop about 2mm from where it was ( not sure on the reading or what not ) but by this rate, I would imagine the bottle lasting 2 weeks which I thought it would of lasted longer then that. If my machine has an hour counter I will be able to tell how many hours I logged with this bottle which should help.

I contacted miller and I will reply with there response.

[PUMPKINHEAD]

crx,
try to find some kids bubbles, even if the leak is at the bottom they'll stick enough to indicate a leak.
i still feel IF you have a leak it's in the reg./cyl joint, take off the reg. and inspect the nipple reg. knob (the seating surface, not the adjustment handle) and with a flashlight the inside the cyl. valve, that mating surface. even a tiny, seemingly insignificant scratch or dent is going to leak considerably at 2k psi.
also, are you opening your tank valve fully? all the way open, those high pressure cyl. valves are double seated, they seal the stem by compressing a gland at the top by being opened FULLY, this would explain the phenomenon of the sinking pressure, IF you were just cracking the valve. it also explains the drop in pressure with the cyl. and reg. closed.

[Fishy Jim]

If the diaphragm seals completely, then you would be measuring the high side. There's no way of knowing if it's leaking a little or not. So the only way to check that would be to plug the outlet and see if any pressure bleeds into it over time.

There's no point in putting teflon tape on the bottle fitting. the threads don't seal anything - that nut shoves the nipple into the beveled face of the bottle seat and its a metal to metal seal. Perhaps you don't have that tight enough?

My first tig bottle barely made 2 weeks. You have to remember, you have 4-10 seconds of post flow for every time you hit the pedal. That's where your hours seem to catch up with you. Tig uses a lot of gas.

[unixadm]

Yup. Post flow is typically 10 seconds after you terminate the arc. I would not try to cut corners and lower this by too much (if it's adjustable on the Sync 200). It helps keep the tungsten protected while it's hot, along with keeping the weld area shielded until it has had time to cool. TIG uses a lot of gas and seriously if you are looking for bleed down, you're in for a long road ahead. TIG is expensive, from the machines to the consumables. That's why you charge more, to cover those expenses. Learning and practice does not always come cheap or free.

[RadMan]

Crx, I have the exact same gauge set as you, when I close the bottle valve the pressure gauge slowly drops, takes an hour or so to read 0 psi.
The flow gauge does the opposite climbing at first then slowly dropping, it'll take several days to read 0.

[90blackcrx]

Crx, I have the exact same gauge set as you, when I close the bottle valve the pressure gauge slowly drops, takes an hour or so to read 0 psi.
The flow gauge does the opposite climbing at first then slowly dropping, it'll take several days to read 0.

So is your's leaking to ? Or is it normal.

Jim its tight, I put a big wrench on it and turned.

Yes I'm opening the bottle all the way also.

[unixadm]

My take on it - NORMAL if you can find no leaks in your fittings.

Have you checked your tank valve stem when closed to see if you are leaking any gas there? It's possible to that the gas is simply leaking back through the valve to atmosphere. The tank valves are plenty used and abused. At least on my takes from a local supplier and Airgas.