Backpurging pipe HELP GUYS

[Bert]

That's really all you need. Argon so readily displaces atmosphere that setting up a purge is not difficult at all. In fact, You don't want any kind of airtight seal as it would negate the positive pressure that a little "leaking" will provide. Lots of times I will just use a spring clamp to attach the argon hose inside a tube and then just tape around the whole thing. Blue painters tape works very well as it leaves no residue behind. Of course, that is dependent on how close you are to the seam but aluminum foil works equally as well.

If you really are then this should be a no-brainer. If you really need to have some off the shelf products for your application and have plenty of cash, you might try a google search.

http://www.cob-industries.com/argweld.htm

D@MN KB!! You hit the nail on the head with THAT link!! I thought it was $20 for a bunch, but when I went to the price list, I saw what you mean!!

[Bert]

That's really all you need. Argon so readily displaces atmosphere that setting up a purge is not difficult at all. In fact, You don't want any kind of airtight seal as it would negate the positive pressure that a little "leaking" will provide. Lots of times I will just use a spring clamp to attach the argon hose inside a tube and then just tape around the whole thing. Blue painters tape works very well as it leaves no residue behind. Of course, that is dependent on how close you are to the seam but aluminum foil works equally as well.

If you really are then this should be a no-brainer. If you really need to have some off the shelf products for your application and have plenty of cash, you might try a google search.

http://www.cob-industries.com/argweld.htm

D@MN KB!! You hit the nail on the head with THAT link!! I thought it was $20 for a bunch, but when I went to the price list, I saw what you meant!!

[Bert]

That's really all you need. Argon so readily displaces atmosphere that setting up a purge is not difficult at all. In fact, You don't want any kind of airtight seal as it would negate the positive pressure that a little "leaking" will provide. Lots of times I will just use a spring clamp to attach the argon hose inside a tube and then just tape around the whole thing. Blue painters tape works very well as it leaves no residue behind. Of course, that is dependent on how close you are to the seam but aluminum foil works equally as well.

If you really are then this should be a no-brainer. If you really need to have some off the shelf products for your application and have plenty of cash, you might try a google search.

http://www.cob-industries.com/argweld.htm

WOW KB!! You hit the nail on the head with THAT link!! I thought it was $20 for a bunch, but when I went to the price list, I saw what you meant!!

[MR.57]

One loaf of french bread will make about a dozen custom-fit header backpurging plugs. It's porous, non-hazardous, flame retardant, conforms to curves, leaves no glue residue, and it's dirt cheap. Another benefit is that if you have a weld where it would be difficult or impossible to remove the baffle afterward just flush the tubing with water and the bread will disintegrate and be harmlessly flushed away. Chore-Boy brand stainless scouring pads work well as dams too. Under $2 at almost any supermarket. Pads

My backpurging hose is regular inert gas line with a short piece of steel fuel line press fit onto the end. I use a Harris 356 twin regulator with two independent flowmeters (one for torch, one for purge) but some people just use a Y fitting and up their flow rate slightly to compensate for purging losses.

If you want a real backpurging dam, look at picture on the bottom left of page 40 and copy the design when you have some spare time to goof around.http://www.millerwelds.com/resources...Book_Chpt4.pdf

[davedarragh]

One loaf of french bread will make about a dozen custom-fit header backpurging plugs. It's porous, non-hazardous, flame retardant, conforms to curves, leaves no glue residue, and it's dirt cheap. Another benefit is that if you have a weld where it would be difficult or impossible to remove the baffle afterward just flush the tubing with water and the bread will disintegrate and be harmlessly flushed away. Chore-Boy brand stainless scouring pads work well as dams too. Under $2 at almost any supermarket. Pads

My backpurging hose is regular inert gas line with a short piece of steel fuel line press fit onto the end. I use a Harris 356 twin regulator with two independent flowmeters (one for torch, one for purge) but some people just use a Y fitting and up their flow rate slightly to compensate for purging losses.

If you want a real backpurging dam, look at picture on the bottom left of page 40 and copy the design when you have some spare time to goof around.http://www.millerwelds.com/resources...Book_Chpt4.pdf

With or without garlic and butter? Sorry, I couldn't resist. Very good idea, however!

[FATFAB]

I have been using the aluminum foil and brake line for three decades. Nothing I have ever used is faster cheaper or simpler.

A note on KB's point about positive pressure, once the atmosphere is displaced, you only need enough pressure to counteract atmosphere. Since the argon is denser than the atmosphere you can get a way with 1 - 3 psig.

[griff01]

Hey guys my name is Ryan and I am an aviation tig welder and fabricator of custom turbo kits on the side. I do A LOT of pipe welding and I REALLLLY need to find plugs I can use for the ends of my tubing to backpurge with and I do not have the time to make them and I know someone out there makes them. I searched and searched and couldnt find anything please help me out. Thx guys
Ryan.

P.S. the pipe im welding is 1.25/1.5/2.0" ID

http://www.intercononline.com/welding/mainpurg.htm
http://files.aws.org/wj/2006/12/wj200612/wj1206-38.pdf

Out of curiosity, I googled "pipe purge dams" and got 304,000 hits. Umm.

Griff

[mark.c]

No need to purge aluminum makes no difference, I have welded pipes 100% xray without purge

[Nathan128]

Foam from an old couch cushion works well or for tape they make that aluminum foil tape it won't burn only the glue gets a bit messy.