how can i setup my tig for back purging
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From: canada
how can i setup my tig for back purging
when welding stainless pipes or whatever.
do i just tape up the ends and run the agron directly from the tank to one end of my pipes? what cfm should i do it at...5-10
do i just tape up the ends and run the agron directly from the tank to one end of my pipes? what cfm should i do it at...5-10
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From: Abbotsford, BC
Re: how can i setup my tig for back purging (integravic)
I havent done much stainless pipe welding but the few times I have I used tinfoil on the ends with a small hole in the tinfoil and ran about 8-10chf, seemed to work fine I had no contamination/sugaring and 100% penetration.
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From: Victoria, BC, Canada
Re: how can i setup my tig for back purging (integravic)
yes just run off the regulator, like you said tape off all open ends and holes. Make a small 1/16 ~ /1/8" hole in the tape at the highest point in the part, argon is heavyer than air. once filled 5 to 10 cfm is good, to keep air from falling in.
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From: Fredericksburg, VA, USA
Re: how can i setup my tig for back purging (integravic)
You can run 2 lines from the same bottle or get another bottle.
Tin foil works well. You should always try filling from the bottom up since Argon is heavier than oxygen. Depending on how large the piece is, will determine how long you need to run the purge prior to welding. But once she's purge it doesn't take much.
Also if you cut off a soda can it slips over 2-1/2" tubing almost perfectly. I use an assortment of the rubber chair leg protectors. Just drill a 1/4" hole in them, slide your 1/4" teflon purge line into it and plug the end of the tube you are welding. Remember you must always allow the gases to come out or once you are about to finish the butt weld the internal pressure will blow the weld out.
Tin foil works well. You should always try filling from the bottom up since Argon is heavier than oxygen. Depending on how large the piece is, will determine how long you need to run the purge prior to welding. But once she's purge it doesn't take much.
Also if you cut off a soda can it slips over 2-1/2" tubing almost perfectly. I use an assortment of the rubber chair leg protectors. Just drill a 1/4" hole in them, slide your 1/4" teflon purge line into it and plug the end of the tube you are welding. Remember you must always allow the gases to come out or once you are about to finish the butt weld the internal pressure will blow the weld out.
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From: Fakeville, USA, USA
Re: how can i setup my tig for back purging (SMSP)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SMSP »</TD></TR><TR><TD CLASS="quote">You can run 2 lines from the same bottle or get another bottle.
Tin foil works well. You should always try filling from the bottom up since Argon is heavier than oxygen. Depending on how large the piece is, will determine how long you need to run the purge prior to welding. But once she's purge it doesn't take much.</TD></TR></TABLE>
SMSP, come on now. When purging with argon you always fill from the top because argon is more dense than oxygen. That way the argon falls to the bottom continously displacing the oxygen.
Good tips on plugging the ends of pipe. I'm going to have to get som chair leg protectors. Tried the soda can, worked perfectly. Thanks.
Tin foil works well. You should always try filling from the bottom up since Argon is heavier than oxygen. Depending on how large the piece is, will determine how long you need to run the purge prior to welding. But once she's purge it doesn't take much.</TD></TR></TABLE>
SMSP, come on now. When purging with argon you always fill from the top because argon is more dense than oxygen. That way the argon falls to the bottom continously displacing the oxygen.
Good tips on plugging the ends of pipe. I'm going to have to get som chair leg protectors. Tried the soda can, worked perfectly. Thanks.
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From: Wellington, NZ
Re: how can i setup my tig for back purging (F20Cteg)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by F20Cteg »</TD></TR><TR><TD CLASS="quote">
SMSP, come on now. When purging with argon you always fill from the top because argon is more dense than oxygen. That way the argon falls to the bottom continously displacing the oxygen.
</TD></TR></TABLE>
But think, if you have the pipe filling from the bottom and a drain hole at the top, the Argon slowly fills from the bottom pushing the air out the top.
Use the opposite if you are using Nitrogen or something lighter than air, fill from the top and it pushes the air out a drain hole in the bottom.
SMSP, come on now. When purging with argon you always fill from the top because argon is more dense than oxygen. That way the argon falls to the bottom continously displacing the oxygen.
</TD></TR></TABLE>
But think, if you have the pipe filling from the bottom and a drain hole at the top, the Argon slowly fills from the bottom pushing the air out the top.
Use the opposite if you are using Nitrogen or something lighter than air, fill from the top and it pushes the air out a drain hole in the bottom.
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From: Fakeville, USA, USA
Re: how can i setup my tig for back purging (Tompen)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tompen »</TD></TR><TR><TD CLASS="quote">
But think, if you have the pipe filling from the bottom and a drain hole at the top, the Argon slowly fills from the bottom pushing the air out the top.
Use the opposite if you are using Nitrogen or something lighter than air, fill from the top and it pushes the air out a drain hole in the bottom.
</TD></TR></TABLE>
No, the argon will just stay at the bottom. Argon is denser than air so it will fall.
The idea is to let the argon fill from the top and fall to the bottom where you would have a drain hole. This will displace the oxygen the best.
Using nitrogen would be the opposite, filling from the bottom.
Simple physics here.
But think, if you have the pipe filling from the bottom and a drain hole at the top, the Argon slowly fills from the bottom pushing the air out the top.
Use the opposite if you are using Nitrogen or something lighter than air, fill from the top and it pushes the air out a drain hole in the bottom.
</TD></TR></TABLE>
No, the argon will just stay at the bottom. Argon is denser than air so it will fall.
The idea is to let the argon fill from the top and fall to the bottom where you would have a drain hole. This will displace the oxygen the best.
Using nitrogen would be the opposite, filling from the bottom.
Simple physics here.
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From: usa
Re: how can i setup my tig for back purging (F20Cteg)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by F20Cteg »</TD></TR><TR><TD CLASS="quote">
No, the argon will just stay at the bottom. Argon is denser than air so it will fall.
</TD></TR></TABLE>
If the flow in continuous then where are the new coming argon is going to go if you said they stay at the bottom? Imagine it was water instead of argon, yes all the water is going to stay at the bottom but as more water was bing pumped in the water level in the pipe is going to rise til it reaches the top then it'll try to come out of the small hole on the other end. Jeez, it's simple common sense.
No, the argon will just stay at the bottom. Argon is denser than air so it will fall.
</TD></TR></TABLE>
If the flow in continuous then where are the new coming argon is going to go if you said they stay at the bottom? Imagine it was water instead of argon, yes all the water is going to stay at the bottom but as more water was bing pumped in the water level in the pipe is going to rise til it reaches the top then it'll try to come out of the small hole on the other end. Jeez, it's simple common sense.
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From: Fredericksburg, VA, USA
Re: how can i setup my tig for back purging (F20Cteg)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by F20Cteg »</TD></TR><TR><TD CLASS="quote">
SMSP, come on now. When purging with argon you always fill from the top because argon is more dense than oxygen. That way the argon falls to the bottom continously displacing the oxygen.
Good tips on plugging the ends of pipe. I'm going to have to get som chair leg protectors. Tried the soda can, worked perfectly. Thanks.
</TD></TR></TABLE>
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by F20Cteg »</TD></TR><TR><TD CLASS="quote">
No, the argon will just stay at the bottom. Argon is denser than air so it will fall.
The idea is to let the argon fill from the top and fall to the bottom where you would have a drain hole. This will displace the oxygen the best.
Using nitrogen would be the opposite, filling from the bottom.
Simple physics here.
</TD></TR></TABLE>
What?
I guess I better go back to Corning Inc. and tell them that the induction furnaces (2100 degrees C) that I redesigned with new Ar, He and N2 purges which have been in use for the last 8 years are all wrong.
SMSP, come on now. When purging with argon you always fill from the top because argon is more dense than oxygen. That way the argon falls to the bottom continously displacing the oxygen.
Good tips on plugging the ends of pipe. I'm going to have to get som chair leg protectors. Tried the soda can, worked perfectly. Thanks.
</TD></TR></TABLE>
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by F20Cteg »</TD></TR><TR><TD CLASS="quote">
No, the argon will just stay at the bottom. Argon is denser than air so it will fall.
The idea is to let the argon fill from the top and fall to the bottom where you would have a drain hole. This will displace the oxygen the best.
Using nitrogen would be the opposite, filling from the bottom.
Simple physics here.
</TD></TR></TABLE>
What?
I guess I better go back to Corning Inc. and tell them that the induction furnaces (2100 degrees C) that I redesigned with new Ar, He and N2 purges which have been in use for the last 8 years are all wrong.
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From: Fredericksburg, VA, USA
Re: how can i setup my tig for back purging (integravic)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by integravic »</TD></TR><TR><TD CLASS="quote">how do i know when the pipe is full? will i here the gas coming out?
thanks for the tips</TD></TR></TABLE>
Gas will come out as soon as you turn the purge on. Well you could figure out the rough volume of the tubing and then with your flow rate calculate the time to flow that same amount of Argon, but no one does that. Plus you'd still have to run it longer to be sure all the O2 is gone. Like I said before, it will depend on the diameter and length of tubing you are purging. When you do it more often you'll get a "feel" of what length of time is enough. If your welds don't look good on the inside then you need to flow it longer before striking that arc.
thanks for the tips</TD></TR></TABLE>
Gas will come out as soon as you turn the purge on. Well you could figure out the rough volume of the tubing and then with your flow rate calculate the time to flow that same amount of Argon, but no one does that. Plus you'd still have to run it longer to be sure all the O2 is gone. Like I said before, it will depend on the diameter and length of tubing you are purging. When you do it more often you'll get a "feel" of what length of time is enough. If your welds don't look good on the inside then you need to flow it longer before striking that arc.
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From: Wellington, NZ
Re: how can i setup my tig for back purging (F20Cteg)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by F20Cteg »</TD></TR><TR><TD CLASS="quote">
No, the argon will just stay at the bottom. Argon is denser than air so it will fall.
The idea is to let the argon fill from the top and fall to the bottom where you would have a drain hole. This will displace the oxygen the best.
</TD></TR></TABLE>
But the Argon would fall through the air and straight out the bottom, ever tried filling a kitchen sink with the plug open?
No, the argon will just stay at the bottom. Argon is denser than air so it will fall.
The idea is to let the argon fill from the top and fall to the bottom where you would have a drain hole. This will displace the oxygen the best.
</TD></TR></TABLE>
But the Argon would fall through the air and straight out the bottom, ever tried filling a kitchen sink with the plug open?
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From: Fakeville, USA, USA
Re: how can i setup my tig for back purging (SMSP)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SMSP »</TD></TR><TR><TD CLASS="quote">
What?
I guess I better go back to Corning Inc. and tell them that the induction furnaces (2100 degrees C) that I redesigned with new Ar, He and N2 purges which have been in use for the last 8 years are all wrong.</TD></TR></TABLE>
Ya they might find out and get pissed.
I have tried it both ways, and this works for me.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tompen »</TD></TR><TR><TD CLASS="quote">
But the Argon would fall through the air and straight out the bottom, ever tried filling a kitchen sink with the plug open?</TD></TR></TABLE>
I meant have the drain at the top which normally would be where the purge line goes. Sorry. The argon will fill up the chamber and the oxygen will be forced out the top.
What?
I guess I better go back to Corning Inc. and tell them that the induction furnaces (2100 degrees C) that I redesigned with new Ar, He and N2 purges which have been in use for the last 8 years are all wrong.</TD></TR></TABLE>
Ya they might find out and get pissed.
I have tried it both ways, and this works for me.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tompen »</TD></TR><TR><TD CLASS="quote">
But the Argon would fall through the air and straight out the bottom, ever tried filling a kitchen sink with the plug open?</TD></TR></TABLE>
I meant have the drain at the top which normally would be where the purge line goes. Sorry. The argon will fill up the chamber and the oxygen will be forced out the top.
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