Why do I keep blowing up water hoses?

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I'm finally starting to get the hang of my new TIG setup but I've got a serious issue that has brought my projects to an immediate halt the past two nights.  I'll be welding away and right in the middle of a bead......BANG!!!!  And coolant is beginning to flood the floor.  Weld-Tec doesn't seem to sell replacement hoses (as far as I can tell) but I picked up a Weld-Craft replacement hose that fit my Weld-Tec torch just fine.  The first night this happened I figured maybe I got a defective hose or something wasn't right.  After it happened the second time, I'm sure something isn't right.  When the hoses popped, there was a fair amount of steam which meant there was pressure in the line, but I really hadn't been welding all that much.  After all, I bought a water cooled torch setup to avoid the "duty cycle" of an air cooled torch.  The torch was barely even warm. It seems odd to me that the line I keep blowing up is the SUPPLY line TO the torch.  If it was overheating, wouldn't the RETURN line be the one blowing up (carrying hot water away from the torch?).  In the water cooler I'm running 1/2 gallon automotive anti-freeze WITHOUT any radiator leak plugging additives.  I know it's advised not to run automotive coolant, but I talked with a guy at Indiana Oxygen Company when I bought the cooler and he said that it's because many coolants contain additives to plug a leaking radiator that end up gumming up the water pumps.  The rest of the tank (2.5-3 gallons) was distilled water.  My setup:  Dynasty 200dxWeld-Tec Cooler WP-20 torchAny suggestions would be appreciated.  I'd rather not buy a new $40 hose every night and even more frustrating is that I have to call it a night when I've still got plenty of work to be done.
Reply:You have a blockage or something.    There should be NO STEAM if the cooler is working right.David.  I cooked one hose because I didn't plug the cooler in.Real world weldin.  When I grow up I want to be a tig weldor.
Reply:I would agree that the water is not flowing. I would try to disconnect the return line to the cooler (with the cooler turned off). Then point the return line into the filler neck for the cooler and turn it on to see if the water is actually flowing through.  If the torch or one of the lines gets plugged it's normal that the feed line with the power cable in it will burst. If the water isn't flowing then the power cable heats up the water in the line, eventually it gets hot enough that it softens the rubber line until it bursts due to it's weakened condition or the cable eventually just melts through. The return line would never get as hot even if that is where the blockage is as the power cable does not run through it.Hope that helps.RegardsEr70S-2
Reply:Do you have your torch setup properly ?I've noticed that you already received some incorrect advice.  The power going towater cooled torches is fed through the return line !  So it should not be an over heatingissue due to power.....See this hook up guide (click here)  Source: Weld-craft torchesIf it is the supply line that is leaking.....My guess would be:1. The pump pressure is to high....do you have a pressure gauge plumbed in the circuit ? Max pressure, according to Lincoln and Weldcraft should not exceed 60 psig @ 1.66 gal/min2. The torch head is blocked....there are several very small orifices in the the head that direct the coolant flow around the collet head.  These orifices willclog easily.  Does your system run a coolant filter ?....if so, check it.Also...I would not recommend running automotive coolant...despite what IOC said, the research I've done and info that I have found always claims that auto coolants tend to develop scum. Not only do the rust inhibitors mess up the system, but oil based coolants will not work properly for this app.Try to get your hands on some pure ethylene glycol........or use theMiller/Lincoln developed coolants.  I think IOC sells the Miller stuff.Just my 2 cents...good luck !CheersAlso, does your system have a flow indicator built in ?-Graham-Mechanical EngineerAutosport Mechanic/Fabricator
Reply:Originally Posted by ER70s-2 Then point the return line into the filler neck for the cooler and turn it on to see if the water is actually flowing through.
Reply:Originally Posted by grahamtheengineerThe power going towater cooled torches is fed through the return line !
Reply:I just got off the phone with Weld Tec and the tech support guy told me it sounds like I've got a restriction somewhere.  He told me to disconnect the return line from the machine and make sure I'm getting the "quart a minute" spec I'm supposed to.  It only took 30 seconds to fill up a quart bottle.  Maybe my pressure is too high?  This seems to rule out a restriction.
Reply:Water cooler pumps usually are shipped preset at 60 PSI for MIG welding applications...  although it looks like the Weldtec cooler comes preset at 50 PSIhttp://tectorch.com/welding%20water%20cooler.htmFor TIG,   50 PSI is the recommended maximum output rate for GTAW torches, and a flow rate of 1 quart per minute.Also, the pumps used on welding coolers generally have an integral strainer-- the Series 1 (at least in the most commonly used Procon pumps)http://www.proconpumps.com/Products.htm#Series1hope that helps.Last edited by CarmenElectrode; 08-01-2008 at 02:04 PM.-----------------------Carmen Electrodewww.CarmenElectrode.comand the boss blogs at  www.JoeWelder.comall powered by  www.Arc-Zone.com
Reply:If I'm getting a much higher flow rate than I should be (2 quarts/minute) should I be turning my pressure down?  This is a bit confusing since it's not always easy to compare flow and pressure.  The pump creates flow of coolant.  Restriction to flow causes the pressure.  Maybe I need to install a pressure gauge and see what it's currently at.  Thanks!
Reply:You're right, by the book the torch should be hooked up with the power cable on the return side, I always run mine the other way. For years I ran off the waterline and always wanted the water going through the power line first and draining out the other side. I don't think it matters much eitehr way as it is just a circulating system when hooked up to water cooler. I think my point is still valid as to which line blows, the one with the power cable in it due to the reasons mentioned before, definitley was not trying to MISINFORM you, just trying to explain why it's that cable that tends to blow. I'm not sure why yours is blowing when you seem to have a good flow rate. I would try another complete torch. Try going to your weld supplier and explain the problem, the guy I deal with is quite good. He should take the original one back with a refund if the complete new torch solves the problem.RegardsER70S-2
Reply:Weldcraft WP 20 water cooled torches need the cool water going to the head then down the power cable to return. You run them backwards and the power cable heats the water up before it gets to cool the head. Then on hot days and more power the plastic hose expands as it is plastic and leaks. To keep from wasting coolant, fill cooler with steam distilled water till you get the flow problem corrected.  I melted two WP20's before I figured out the other welder hooked the hoses up incorrectly. By the way you cannot see steam. Real steam is invisible, what you are seeing is just water vapor. Oh I see the hook up has been mentioned before my post. Oh well nevermind.Last edited by GSteve; 08-04-2008 at 02:10 AM.
Reply:Originally Posted by tmorgan4I just want to make sure I don't blow up another hose and lose a couple gallons of $25/gallon coolant!!!  Thanks again.
Reply:By the way you cannot see steam. Real steam is invisible, what you are seeing is just water vapor.That's not correct. Superheated steam is "invisible", assuming it is vented into a space that doesn't provide enough cooling to cause some vapor to condense, which it will in many circumstances, but not all, depending on the temperature of the superheat. Regardless, though at 600 PSI, and 750 degrees, if there's a little vapor in it so I can see it, you can be sure I'll respect it as real steam.Saturated steam by definition has a small abount of vapor in in, as it hasn't been heated above it's saturation temperature. That would be most steam people outside of the power industry see. It takes superheaters (with gas pass temps in the mid to upper 1000 degrees) to get it hot enough to where "It's invisible."Last edited by rat4spd; 08-04-2008 at 09:13 PM.
Reply:Originally Posted by rlitmanOuch!  Dex Cool costs me about $12/gallon with another $1.50 per gallon for distilled water, bringing it to under $7/gallon for just about as expensive car coolant as you can get.RV antifreeze is pretty much pure ethylene glycol (or propylene glycol, which I would highly recommend if you can get it), and is quite a bit cheaper than automotive coolant.
Reply:Still remains what you see is water vapor from my under standing. Steam is an interesting subject for me. PM me so I can get educated to what you know. Many books written on the subject, I could have gotten the wrong ones. Thanks.
Reply:tmorgan4,Sounds like you've verified that the supply and return hoses are installed correctly.  Also seems that you have verified that there is adequate (to say the least) flow thru the torch.Could you possibly be allowing the hose to come into contact with the newly created weld bead, thereby melting the plastic feed line?Are you using superflex hose or just the standard black plastic tubing?Are you using a torch sheath (leather, nylon, or kevlar) to protect your torch hoses?If you've checked all these things, as well as the other comments, I'd suggest returning the complete torch assembly to who you purchased it from with a request for a replacement.PS.  There have been entire articles written on why NOT to use automotive or RV anti-freeze in a tig cooler.  You may wish to do a search on the Miller and Hobart boards.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.