Welding Tips and Tricks

I'm going to do the helium mix that Jody is always talking about in his tig videos, where he is using mostly argon, with a tiny bit of helium. I'm mostly welding aluminum.

I've got the two tanks, and two flowmeter valves. What type of check valve to I need to be using? I see that the most popular type are the "spring valve" type. Is this adequate for this purpose, or do I need to be using something different, and if so, what type of valve would this be called?

Thanks!
Steve

Welcome to the forum Steve.
In my opinion there is no need to use check valves at all - very few I've seen will hold helium anyway & unless you are using an insane pressure differential between the two regulators it will make no real world difference - my only advise is to try & find conventional adjustable pressure regulators & run them at the lowest possible pressure to achieve your desired flow thus reducing the huge pressure surge on solonoid opening & keep the pipes as small as possible . avoid those flow only adjustable things that Lanse likes - also if the helium flow meter is not calibrated for that gas you only need the ball to quiver at the bottom to give you sufficient flow.

I set mine up last month with a Y fitting for the gas lines and a regulator for each tank run into the Y

I don't have a gas meter but this seems to work OK to have an adjustable blend of helium introduced into the argon stream

No check valve here

Adam



707 / 579-9290
Sent from my iPhone

The only reason check valves would be an advantage would be when your tanks get almost empty. As you use both tanks at separate rates the won't maintain an equal pressure with out resetting your regulators all the time. As the tanks get emptier this will need to be done with increasing frequency.

Yeah just use 2 flowmeters. Takes some experimentation to dial it in. And you really need to be proficient TIG welder first

Tried it, and I have to agree
You have to have a good grip on what you are doing before you try the blend gas tricks.

At least know what you are looking at

Adam

technosteve wrote:I'm going to do the helium mix that Jody is always talking about in his tig videos, where he is using mostly argon, with a tiny bit of helium. I'm mostly welding aluminum.

I've got the two tanks, and two flowmeter valves. What type of check valve to I need to be using? I see that the most popular type are the "spring valve" type. Is this adequate for this purpose, or do I need to be using something different, and if so, what type of valve would this be called?

Thanks!
Steve

The regulators on each bottle, before the flow-meters, will serve well as check-valves. They will take the full back-pressure of one bottle if you disconnect the other. This is not "best practice", but neither is unhooking one bottle with the other "on".

You will not accidentally mix your bottles if you don't use check-valves.

Ideally, your argon and helium bottles will have regulators set at equal pressure (perfect is not important) so your mix at pre-flow is about the same as mix during the weld. You also do not need a "wye". A "tee" joint will mix the gas just fine. Helium disperses into it's environment almost instantly.

Someone above pointed out, helium has negligible effect on an argon flow-meter ball. If the ball is "dancing", you're between 5-8 CFH, and if it's "just" steady, you're about 10 CFH.

Happy experimenting! I think you'll love it.

Steve S

Here is another way to get as bit more accurate reading on helium and/or CO2 mixes with argon. Cheap low flow CO2 flowmeter off eBay marked from .5 to 15 CFH. Then figure the CO2 to helium conversion factor and write that on the tube with a Sharpie.

Great idea - wish I'd thought of it ! I only ever guess the flow by listening at the cup - hate those flow meters though - I think they are sold cheap by gas suppliers as they tend to have 50 > 75 psi fixed pressure regulators - the initial surge wastes gas like leaving a valve torch on & forgetting it ( obviously I'd never do that !! )

Could I use this as a "Y" adapter ? I have two flow meters . Never needed helium, just curious as I have about ten of these things. Thanks much
--------------------------------------------

[quote="subwayrocket"]Could I use this as a "Y" adapter ? I have two flow meters . Never needed helium, just curious as I have about ten of these things. Thanks much
----------

It should be fine. Thread it directly into your machine's gas input, and thread two flow-meter outlet hoses to it, and you're golden. I'd leave the valves wide open and set the flow at the bottles, but you have a pre-made wye with the right connectors.

Steve S

Otto Nobedder wrote:
The regulators on each bottle, before the flow-meters, will serve well as check-valves. They will take the full back-pressure of one bottle if you disconnect the other. This is not "best practice", but neither is unhooking one bottle with the other "on".

You will not accidentally mix your bottles if you don't use check-valves.


Steve S

I spoke an un-truth... The flow-meter regulators will not serve as check valves in the manner I stated. They will do fine as long as both bottles are above the regulator set-pressures by a factor of, say, two. (If you set this up without check-valves, and disconnect one bottle without shutting the other off, it will back-flow through the open regulator. No one would do this, but that's where I misspoke.) If you run one bottle down near regulator set-point, the other bottle can feed back in to it at the end of a weld when line pressure comes back up. This may be the basis for Jody's use of check valves.

Steve S

The Y adapter is what I got, with independent regulators
Seems to work OK from what I tried at the house. Still not the same thing as a gas mixer though and I do know that )

Adam

Otto Nobedder wrote:

subwayrocket wrote:Could I use this as a "Y" adapter ? I have two flow meters . Never needed helium, just curious as I have about ten of these things. Thanks much
----------

It should be fine. Thread it directly into your machine's gas input, and thread two flow-meter outlet hoses to it, and you're golden. I'd leave the valves wide open and set the flow at the bottles, but you have a pre-made wye with the right connectors.
Steve S

Thanks much . I was thinking with I could leave the helium knob turned off until I needed it ...this way i'd eliminate any backflow prob . btw , I just caught on to your screen name ...I oughta know better ...haha

Yeah, the screen name came about the first time I ever signed up for a forum. I'd noticed many who used their e-mail addresses, and started to do the same... Then I did a face-palm and said, "You ought to know better!" and it just clicked.

It's hardly original, as I found. I googled it, and found several previous and prominent uses. One example, Otto was a cartoon used by one of the railroads to teach passenger safety.

Steve S