I'm Working On 316 SCH 10 Stainless And I Have A Setup To Back Purge That Consists Of Two End Caps One With A Threaded Hole For My Argon Line. On My Tank After The Reg I Have A Y With Two Valves.
My Problem Is This. As I Got Near The End Of my Welding On The Pieces I Was Joining The Weld Went To ****. It Started Welding Like I Had No Gas At All.(Yes The Gas Was Still On) I Think The Problem Might Be Too Much Pressure In The Pipe.
I'm Not Exactly Sure How to Setup My Working Pressure With The Y It Seems Like There Isn't Enough Pressure At The Tig Torch When I Run At 25-28. So Do I Need To Run The Y Then A Reg At Each End Of The Y? And What Should My Working Pressure Be For Backpurging?

Thanks
Kyle

 

Well, you do not want pressure in the pipe. Run argon in one end, and on the other end, you need a hole that's at least as big as the hole going in.

Sounds like what's happening is that when you almost get the seam sealed up, the argon is blowing out.

Using the Y:

Lets say you want to run 20 on the torch and 15 on the purge....oh, and that's CFH, not PSI.

So, turn your purge side of the Y wide open and shut the torch side.
1) Bump your pedal so that the flow starts.
2) Set the floweter to 35CFH (that's 20+15)
3) Now, with the flow still going, slowly turn down the purge side of the Y till the flowmeter will only flow 15CFH. Now you have your purge side set.

4) Now, you can just crank the torch side open and weld. Basically, you're regulating the overall flow at the flowmeter, then using the valve on the Y to regulate the maximum that can flow to that side....and the rest will go to the torch.

 

Engloid pretty much nailed. I just post to say that the way you type is really annoying and you do it in every post you make, I'm pointing this out so next time you ask for help, people will actually try to read and help you put.

 

Engloid, Not To Sound Stupid But I Tried What You Said I Followed Your Directions And It Didn't Seem To Work.

The First Problem That I'm Running Into Is That When The Purge Valve Is Wide Open It Doesn't Flow Any Gas To The Tig Torch Even When The Valve To The Torch Is Wide Open. I Think This Is Becasue The Gas Is Following The Path Of Lest Resistance(The Purge Side)

This Is My Setup If That Helps

 

you want to tee off the lines before the flow regulator for the tig-gun. it's good to add another regulator for the purge line--that way the purge line wont rob all the gas from the tig gun.

 

If your diagram is correct, you're missing a valve in the line between the flow meter and the open end of the purge line. The point here is to be able to regulate the purge gas. No valve in the line = no way to regulate.
Our setups go from the tank to the manifold. Then one line goes to the flow meter, then to the torch. Another line goes to a valve and out of the valve to the purge line.
We don't use flow meters on the purge, we just make sure after one pass the weld looks good and if not open the valve a little more (easiest valve to use is a ball-**** type)
Like Engloid said- if the only place for your gas to escape is the joint, then it's going to blow out on you.

And For God's Sake Stop Typing With All Capitolized First Letters!!!!!!!!!!

 

There is a valve between my flo meter and the open end of my purge i have also put to 1/4 inch holes in my end cap that was closed off. I think i'm going to need to get another flometer and put the 2 after the Y because I'm not really able to regulate the flow with the valves on the Y. all I can do is set the flow to around 35 and turn the purge down until i can her gas coming from the torch that sounds about right.

as for the weld that gave we trouble when i thought it was gas flow. after i cleaned the weld up good for my second pass it did the same thing(Welded like there was no gas. So I then took the die grinder and took the weld down and it still did it a little. i have no idea why.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Kyssrt-4 &raquo;</TD></TR><TR><TD CLASS="quote">Engloid, Not To Sound Stupid But I Tried What You Said I Followed Your Directions And It Didn't Seem To Work.

The First Problem That I'm Running Into Is That When The Purge Valve Is Wide Open It Doesn't Flow Any Gas To The Tig Torch Even When The Valve To The Torch Is Wide Open. I Think This Is Becasue The Gas Is Following The Path Of Lest Resistance(The Purge Side)
</TD></TR></TABLE>

....if you followed my instructions, your purge valve should not be wide open
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Brandon Clifton &raquo;</TD></TR><TR><TD CLASS="quote">If your diagram is correct, you're missing a valve in the line between the flow meter and the open end of the purge line. </TD></TR></TABLE>
The splitter has a valve on each outlet.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Kyssrt-4 &raquo;</TD></TR><TR><TD CLASS="quote">all I can do is set the flow to around 35 and turn the purge down until i can her gas coming from the torch that sounds about right.
</TD></TR></TABLE>
If it works, just do what you have been doing.