Using water cooled torch as air cooled?

[Fusion]

I'm considering a PowerTIG 250EX.

I've been in e-mail contact with the welder where I used to work asking for his opinion on TIG welders.

He noticed that the 250EX comes with a water cooled torch yet the water cooler is an option.

As he put it:

One thing I did notice about the Everlast is the torch listed on the site says it's water cooled but the standard package does not have a water cooler included (it's in the optional column). This is a no-no, never run a water cooled torch without the coolant running, ever. Make sure you either get an air cooled torch or that you add the water cooler to your list of things to buy.

Why would Everlast include a water cooled torch in a kit that does not include the cooler?

[performance]

Well, its darned if we do, darned if we don't thing. If we put an air cooled torch with it, people would ask us why we would dare put an air cooled torch with a unit that has the amp capability that requires a water cooled torch since it would burn up the air cooled torch likely if they went to 250 amps with it.

It's simple enough to buy a cooler as an add on. You can also make your own cooler, or even just use a water hose to cool the torch (if you have a drain in the floor or a flowerbed that needs a little extra watering outside the shop door...all of which customers have done.

Consider the torch a freebie and order it like you want. Most companies don't even include a torch with a unit like that.

[DaveO]

Welcome to the forums, Fusion!

My take on it: the 250EX is a serious enough machine that someone considering it would as like as not already have a cooler, so including it would only add to the cost unnecessarily. Automatically including a cooler with the welder would be like automatically including a pickup truck with the purchase of a trailer, on the assumption that the buyer did not have a vehicle to tow the trailer.

If you're thinking of a 250EX because that's the machine with the capabilities you need, there are plans to build your own cooler, or as a workaround you could run tap water from a sink and run the return water from the torch into the drain. Or as your friend says, use an air-cooled torch.

What kind of projects do you have in mind? Again, welcome to the forums!

[Fusion]

You can also make your own cooler, or even just use a water hose to cool the torch (if you have a drain in the floor or a flowerbed that needs a little extra watering outside the shop door...all of which customers have done.

Thanks Mark, the latter is what I was considering doing for now. My friend just made me aware of possible freezing if left in the garage, which I already thought of. The torch would be stored in my house during the winter months to prevent that.

[TheGary]

If you purchase a cooler you can use an antifreeze in the tank because it is recirculted . You will get a little evaporation over an extended period of time because the system is not sealed . So you may need to add a little to it once or twice a year. There are several products on the market made specifically for this application. I had a propeller repair buis. for about 5 years and used an air cooled torch the whole time. Several times I pushed the max amps on my 250 amp machine for short welds that were maybe 2-3 min. with no problems other than a very warm glove. If I had more welding than that where I needed a lot of amps I just preheated the part to a couple hundred degrees and ran at a lower amp setting. Unless I had a steady diet of parts that need high amp welding I would not use a water cooled torch on a machine ( primarily because my buis. is mobil ) . I get very little repetitive parts because of the nature of my business . You need to analyze how you are going to use your machine. You need to use common sense if you do go with air cooled torch. If you want it to be a no brainer then go water cooled . Do not try to use your water cooled torch without running water through it or you will burn it up even at very low amps. An air cooled torch is made with a heat sink to dissipate the heat for cooling. The water cooled torch does not have that. If you go with air cooled get the highest amp rated one you can get. That is going to be 200 amps and will cover 95% of what most people will ever do.

[TheGary]

One thing to consider if you run an open water system to your torch like running tap water is that mineral buildup will occur at the point of highest heat over a period of time. Many years ago I ran a tig welder at a pattern shop with just an open drain system . This would happen and I could feel the torch getting hot. I would dismantle the torch and clean out the water line of all the minerals and was good to go for another year or so. I would run that torch 4-5 hrs a day though so it does not happen very quickly.

[Blaster]

Do not try to use your water cooled torch without running water through it or you will burn it up even at very low amps. An air cooled torch is made with a heat sink to dissipate the heat for cooling. The water cooled torch does not have that.

I'm not sure, but I assume the other important difference between the Air/Water cooled torch is the gauge of wire in it (having just melted my WC power hose ). I was surprised to see such a thin wire rated at 250A. It's the passing coolant, flowing thru it, that allows that though.

[performance]

Actually there isn't a lot of difference in the hoses. The difference is that there is argon flowing through the cable and it helps cool it. But then there are two types of air cooled setups. The first is the two piece design that utilizes a separate gas line and a insulated,solid, but braided copper cable similar to what you'd find on a welding lead. The other is the single piece line that has a bare copper braided cable "floating" inside tubing. For water cooled units this is the return path for the water. This type setup utilizes 3 lines. For air cooled units this is the argon path to the torch IF it's a single piece design. Two piece designs are stiffer but can carry more current naturally.

[Blaster]

It looks like 12ga wire to me, I can't imagine Argon flow doing the job of removing the heat from it that liquid would. I mean, a 250A AC torch would use that light a gauge wire in it? That's surprising,,,, I think of 12ga being like a 30A wire....

[performance]

Air cooled torches with a single line top out at 175 amps AC, 200 amps DC typically...at 60% duty cycle. The torch may top out at 250Amps, but that is usually DC, and 200 amps AC for the very highest rated torches at 100% duty cycle. CK has some exceptions, but that's the general rule.

Even at 30 amps at 120V for 12 gauge the math is about right...keep in mind there is argon gas flowing over it. We're only dealing with a max of 18- 20V. Total wattage plays significant role. 120V @ 30 Amps. 3600watts...divide that by 18V that's 200A.

[Fusion]

An air cooled torch is made with a heat sink to dissipate the heat for cooling. The water cooled torch does not have that.

If that is the case, then I can understand that.

As for the rest of the responses, all points taken. Thanks.

I will end up getting an air cooled torch as well. Less bulk and I'll get a cooler when the time comes or if they come up with a package deal at the time of purchase, I might go with it.

[Blaster]

Air cooled torches with a single line top out at 175 amps AC, 200 amps DC typically...at 60% duty cycle. The torch may top out at 250Amps, but that is usually DC, and 200 amps AC for the very highest rated torches at 100% duty cycle. CK has some exceptions, but that's the general rule.

Even at 30 amps at 120V for 12 gauge the math is about right...keep in mind there is argon gas flowing over it. We're only dealing with a max of 18- 20V. Total wattage plays significant role. 120V @ 30 Amps. 3600watts...divide that by 18V that's 200A.

Respectfully, I donno....

First I was talking about Automotive wiring, not house wiring (in which 12ga is considered 20A wire)

On my table, where I depend on the Ground coming from simple contact with the piece, there are times when I'm think there might be too little (it's uneven, or just the "legs" of something are touching). So I use a 8ga "jumper", clamped to the Ground Bar all my machines clamps are on, that I use for an additional path sometimes during High Amp welds. Despite my piece laying on the table I've often seen that wires insulation looking "dark" and have felt a Lot of Heat in it. That's a 3ft piece of 8ga and only an Additional Ground!

I have to believe that 250A, pushing through 25ft of 12ga wire, just Has to require significant cooling. Much more than just passing "Air" through it at the Argon flow rate could do.

Here's a, 12V, Automotive chart -> http://www.offroaders.com/tech/12-vo...gauge-amps.htm

They say at the 12-14v your vehicle sees, a 12ga wire, at 25ft, MAXES-OUT at 18A! (I'm sure that's with a LOT of leeway, but it not even close to 250A)

[Paul Moir]

Those chart, including the electrical codes, are based on voltage drop rather than the capacity of the conductor. Of course you can't tolerate much voltage drop on a 12v system, and houses can have runs 100' long. If you look at the building electrical codes they'll make you make the conductor larger for long runs.

10' of #12 has a resistance of 0.016 ohms, so at 250A the voltage drop across it will be 4v (V=IR, I is current). The total dissipation will be 4V*250A=1000W. 1000W would be a lot for a 10' air cooled wire (100W/ft) or so the insulation would melt, but I doubt the copper ever would. Taking out 1000W with water and keeping the temperature under say 90 degrees should be pretty easy though. I expect the Everlast welders can push their voltage up the 4v to get the required current, that is to say I think they operate like a constant current source.

Note that's back-of-the-envelope type calculations. The wire resistance goes up with temperature so you can get into thermal run-aways. Eg with a 100 degree temperature rise, that 100W/ft becomes 170W/ft. Now the wire gets hotter.

[performance]

The 12 gauge wire is just a guess. A wrong one from what I've seen. This is a fine braded wire, not a twisted one, without insulation and it's more close to 3/16-1/4" thick on the torches I've had apart.

[Blaster]

The 12 gauge wire is just a guess. A wrong one from what I've seen. This is a fine braded wire, not a twisted one, without insulation and it's more close to 3/16-1/4" thick on the torches I've had apart.

It maybe a Guess, but an Educated one (I've done a Tremendous amount of Automotive Wiring)

So, 3/16? 1/4"? Not even an 1/8.... And believe me, No One was more surprised than ME!

Since I destroyed my WC Power Hose on my 250A CK torch I was contemplating trying to repair it to a shorter length (to be honest, I like taking things apart anyway....) and here's what I found.

The Entire hose is not much more than 1/4"



The conductor is between 3/32-1/8 "lose and relaxed" in the hose



A comparison to a 3/32 Tungsten when pulled tight



Again, VERY SURPRISING to find such a light gauge wire in a 250 Amp Torch. But, as I said, I think that liquid is doing a significant job of removing Heat. The point I was originally making was, chances are, an AC torch of the same Amperage Rating must have more copper in its power lead as well as a bigger heatsink in the head....

[jakeru]

You are correct that an air cooled torch will have a much heavier gauge braided copper conductor inside its one-piece lead than a water-cooled setup will have, because one is bathed in coolant while another in only inert gas (and although helium might provide some significant cooling of the conductor here, argon certainly will not with its property of having very poor thermal conductivity).

I dissected a WP-17 style air cooled torch lead that failed from overheating and posted pics in another thread a while back, which I just found. My WP-17 torch lead (which is a 150-amp air-cooled class) used a .183" OD copper braiding (about 6-8 gauge) in its conductor:
http://www.everlastgenerators.com/fo...=4899#post4899

[zoama]

The point I was originally making was, chances are, an AC torch of the same Amperage Rating must have more copper in its power lead as well as a bigger heatsink in the head....

Your 250 amp CK torch is rated at 100% duty cycle, AC and DC. The head of CK torches has a larger cooling jacket than it's competitors <-CK20 | Weldcraft 20->