[jbyrd]

On this site and others I have read about using a inert gas Y to roughly mix Helium and Argon for better heat transfer and using less amperage for thicker Aluminum. I have everything for this setup except the gas check valves. Which valves are used for this and where are the installed? On the regulators or on the gas Y? Can someone provide recommended part numbers? I am using a Western 411 inert gas Y. Any help would be appreciated!

Jay

[kermdawg]

Pretty sure you would have to put the check valves in before the Wye fitting. I always thought they went right on the end of the outlet from the tank.

[jbyrd]

Yeah I figured they would either be on each regulator before the hose or on the supply side of the Y just after each hose. But not sure which and am hoping someone can supply specific part numbers to be able to order online. Going to my local welding supplier and explaining what I am doing is an excercise in futility. Thanks!

[kermdawg]

tell me about it :p Did you try airgas or something like that?

[jbyrd]

Yeah it is really frustrating. I tried going in there to purchase the inert gas Y and they asked what I was using it for, so I explained about mixing the Helium and Argon and the look on there face was as though I had just ripped a hole in the space/time continuim. Next thing I know they are showing my brochures for a 1500 dollar Smith gas mixer. I tried explaining that I was mixing Helium and Argon for TIG welding aluminum not some other gas mixtures which have less of a 'fudge' factor. I said thanks but no thanks and then ordered it from Weldfabulous.

I can only imagine going in there and asking for the correct check valves for either my flowmeters or my gas y. I shudder at the thought!

[Sarge]

Airgas has tanks that it comes pre-mixed in one tank. They have different % mixes available. That may be why they look at you like you are growing antlers. It does not make sense to them for someone else to do at home, what they do for money.

[sschefer]

Airgas has tanks that it comes pre-mixed in one tank. They have different % mixes available. That may be why they look at you like you are growing antlers. It does not make sense to them for someone else to do at home, what they do for money.

Air Gas only carries check valves for OxyAcetlyne gauges. They're too small for the Y fitting. I got my Smith mixer for about 1200.00 on the internet. I tried the Y fitting and it was more guess work than science. I really didn't get the results I was looking for until I put the mixer on. I now weld 1/4" 5052-H32 and 6061-T6 with 185 amps using a 80Ar/20He mix. I used to need 225amps with straight Ar.

The pre mixed gas that AirGas has is not as good as mixing it yourself. He being lighter than Ar tends to move up, (or the Ar settles) in the tank. The 250 tank that I tried ran hot at the begining and I occasionall had a hard time with arc starts. At about 1500 psi it started taking more current to do the same welds. By the time I got down to the end it was just like pure Ar. If you do buy a tank of He, make sure you get Ultra High Purity (99.999% pure). There are a couple of grades above that but UHP is fine. Don't try to use Balloon gas, it has 16% Oxygen in it so it can support life when kids (and some adults) inhale it and then talk like Donald Duck.

[kermdawg]

I read somewhere (I think on here) with those premix tanks that ya, like sschfer said, the argon (which is heavier than the helium(which is lighter than air)) tends to settle at the bottom, so you need to mix it up somehow. If you know the way to roll a cylinder, that works, but the best way is to crack it open for a second, like you do with an oxygen cylinder before you hook up the regulator for your torch. Thats suppose to mix the gas or somethin.

[StephanusThie]

Why do we need check valves? For security??

[rahtreelimbs]

Why do we need check valves? For security??

I believe so as not to mix the two gases in each of their respected tanks!

[allessence]

Its so you can't have back flow from one cylinder/regulator to another..

I use reg/flowmeters that are all 50psi intermediate pressure ( from here on IP).. it's handy to know if yours are more or less, and some are more some are less..

if your reg is set at 50psi IP on your argon tank and your reg/flowmeter on your HE tank is a 25psi IP and the argon tank has 2000psi and your HE tank only 2000psi they will equilze pressure into the hose..

If the tank pressure is different from one to the other the tanks 2000psi vs anything lower the tanks will try and equilize pressure.

The check valve stops this from happening. A regulator only works if the pressure on the down stream side is lower then the upstream side. Kind of like a pressure activated shuttle valve.. Once the flow is stopped the pressure is even on both sides of the diaphram and it shuts off the flow.

Once there is a pressure drop it opens and the argon/he or what ever is allowed go escape past the high pressure/low pressure seat.

If the pressure on the downstream is higher than the upstream it will flow backwards.

Here is a link to some pic's of the y splitter and reg's. I use argon and CO2 for the mig so pull argon from the tig.


https://picasaweb.google.com/1153390850 ... 9876715842

https://picasaweb.google.com/lh/photo/6 ... -exif=true