Tip for reducing wasted shielding gas
Posted: Wed Sep 15, 2010 12:35 pm
Hey folks -
I came up with a trick that reduces wasted shielding gas that I wanted to tell you all about.
The hose connecting my argon regulator (HTP brass floating ball type) to my TIG machine (Everlast Super200P) is about a 6' long, and is 1/4"ID, oxygen-approved, green rubber hose. This large diameter of hose is really not ideal for this purpose, because it allows a lot of gas to store in the hose between uses. (When the solenoid stops, the pressure in this hose rises, up to 50 psi for most flowmeters, and it stores a bunch of argon.) If you have a similar setup, this is what you may notice being expelled rapidly out your TIG cup when you trigger the pre-flow solenoid to open.
Well I found a "fix" that is remarkably simple, cheap, and effective. What I did was got some 1/8"ID, 1/4"OD clear, flexible PVC tubing, and I managed to shove that into the 1/4" ID argon hose. (This wasn't really that easy to do, but I found pulsing some compressed air into one end of the 1/4" hose allowed the little tube wiggle in through the other open end, a little bit at a time.) The purpose of the inner tubing is just to take up space to reduce the volume of the compressed argon inside the hose. The result is, when the solenoid stops after post flow, the floating ball argon meter only registers a flow for about 1 second (with the 1/4"ID hose, it would register a flow for about 4 seconds.) Also the sudden "whoosh" of argon during pre-flow is much less dramatic now. I expect I'll be able to use a shorter pre-flow setting, as the TIG cup flow is stabilizing more quickly now.
So I effectively reduced the ID of this hose without needing to change brass fittings or buy a special hose, etc.
Although I haven't welded much with the new setup, I can tell immediately that it is a much nicer setup now. I recommend it to others experiencing a dramatic "sudden argon whoosh". And even with the 1/8" ID hose, I can still dial in enough flow to peg my flowmeter's ball all the way to the top (60+CFH), so it does not cause an excessive restriction for this application. And the cost of the 1/8"ID hose from the local hardware store was only about $3.
If you can find some 1/8"ID Polyethylene (milky white) hose, that may be a good option too, because it is more rigid and slippery than the PVC, so may be easier to slip inside the 1/4" hose. However the PVC hose if you can get it installed, will be real kink resistant.
I came up with a trick that reduces wasted shielding gas that I wanted to tell you all about.
The hose connecting my argon regulator (HTP brass floating ball type) to my TIG machine (Everlast Super200P) is about a 6' long, and is 1/4"ID, oxygen-approved, green rubber hose. This large diameter of hose is really not ideal for this purpose, because it allows a lot of gas to store in the hose between uses. (When the solenoid stops, the pressure in this hose rises, up to 50 psi for most flowmeters, and it stores a bunch of argon.) If you have a similar setup, this is what you may notice being expelled rapidly out your TIG cup when you trigger the pre-flow solenoid to open.
Well I found a "fix" that is remarkably simple, cheap, and effective. What I did was got some 1/8"ID, 1/4"OD clear, flexible PVC tubing, and I managed to shove that into the 1/4" ID argon hose. (This wasn't really that easy to do, but I found pulsing some compressed air into one end of the 1/4" hose allowed the little tube wiggle in through the other open end, a little bit at a time.) The purpose of the inner tubing is just to take up space to reduce the volume of the compressed argon inside the hose. The result is, when the solenoid stops after post flow, the floating ball argon meter only registers a flow for about 1 second (with the 1/4"ID hose, it would register a flow for about 4 seconds.) Also the sudden "whoosh" of argon during pre-flow is much less dramatic now. I expect I'll be able to use a shorter pre-flow setting, as the TIG cup flow is stabilizing more quickly now.
So I effectively reduced the ID of this hose without needing to change brass fittings or buy a special hose, etc.
Although I haven't welded much with the new setup, I can tell immediately that it is a much nicer setup now. I recommend it to others experiencing a dramatic "sudden argon whoosh". And even with the 1/8" ID hose, I can still dial in enough flow to peg my flowmeter's ball all the way to the top (60+CFH), so it does not cause an excessive restriction for this application. And the cost of the 1/8"ID hose from the local hardware store was only about $3.
If you can find some 1/8"ID Polyethylene (milky white) hose, that may be a good option too, because it is more rigid and slippery than the PVC, so may be easier to slip inside the 1/4" hose. However the PVC hose if you can get it installed, will be real kink resistant.