Thread Tape?

[architect]

Newbie TIG here. I turn off my argon tank valve when done. But I find that there's a really slow leak that isn't exactly evident but will lead to the pressure drop all the way to zero over night. Is this a acceptable? I'm reading mix things up using thread tape for welding.

 

[DavidR8]

I don't use thread tape. The fitting are all self-sealing.
I would check your connections from the tank to the back of the machine first with soapy water.

 

[combustable herbage]

Are you saying that you close the valve at the tank and the gauge shows pressure and then the next day there is no pressure?
you could see if it goes down if you turn off the regulator too that would eliminate from the regulator to the tank it maybe such a small leak you may not find it but try the soapy water if there a big leak it will show up.

 

[architect]

Yes I turned off the valve at tank and no pressure drops in that moment but the next day it's all gone. I have tightened all connections with a wrench so that's why I feel like I have no other option but thread tape? Maybe I'm not torqing down on the connections hard enough...

 

[Chicken lights]

Yes I turned off the valve at tank and no pressure drops in that moment but the next day it's all gone. I have tightened all connections with a wrench so that's why I feel like I have no other option but thread tape? Maybe I'm not torqing down on the connections hard enough...

I would try the liquid thread sealant, myself. You don’t need much but it serves to lubricate when tightening fittings as well as help seal them

 

[combustable herbage]

Personally I would check with soapy water to see if there is any leaks and if you don't see bubbles then its probably such a small leak that I wouldn't worry about it, reminds me of my compressor hose it has a small leak in the hose same thing I disconnect the hose and the pressure stays but its not worth it to replace the hose for that its still fully functional. You just have to remember to shut off the tank after use. I'm not sure the tape will help you.

 

[Janger]

After your turn off the tank I am assuming the pressure is gauge is showing the pressure remaining in the welder and hoses downstream from the cylinder valve? I think a slow leak is those systems is pretty typical. Mine does that. Anyone else? I believe they tell you bleed off the remaining pressure anyway to reduce wear on the components.

I suspect the solenoid valve in the welder leaks. I’m not sure what you would do about that. Everybody do North American welders leak a bit? Would a very low flow keep the argon in the hose to the torch uncontaminated? Maybe this is on purpose?

 

[Tom O]

Mine bleed out overnight too from the regulator to the solenoid. I think that is normal and don’t give it a second thought.

 

[Brent H]

Hey @architect - the gas that is in the line from the tank to the welder is not a whole lot in the grand scheme of things. I typically disconnect the hose from the welder and bleed off any residual pressure after the days welding is over.

I would agree with @Janger that if you left the welder connected the internals of the welder would probably let enough of the remaining gas out over a 24 hour period.
If you want to check your leakage - close off the tank valve and then shut the flow meter off as well trapping the high pressure gas in the regulator. Leave that over night and see what you have. If it stays up to pressure then you know the pressure drop is in the hose or welder - chances being greater that it is the welder.

check and see if your welder auto purges itself when it is shut down. Could be that without power at gas control solenoids they cannot hold back any great pressure and simply bleed out.

 

[architect]

Thanks for the thoughts. If this is normal and acceptable then I will just leave it. I'm also just thinking of the dollars leaking out overnight it may just be pennies here lol

 

[DPittman]

"Mine does that. Anyone else? I believe they tell you bleed off the remaining pressure anyway to reduce wear on the components"

What @Janger said.

 

[RobinHood]

Same here: it bleeds down after the regulator - so I just dump the pressure before power down using the purge function after closing the bottle and backing off the flow regulator to take the pressure off the spring.