Understanding a water cooled torch operation

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Since I am assembling my water cooled torch setup with parts from various sources, I will not have an assembly drawing like one I assume I would get if I purchased a complete system. I assumed incorrectly that the water in and out lines would go to the cooler and the gas line is the torch connection, connecting via a gas-through Dinse connector to my Syncro 200. I was quite surprised then to find that the adapter sold for water cooling a torch on the Syncro 200 had both gas and water connections. I found a thread online (possibly here at WW) with a schematic, but being the pain in the a$$ that I am, I want to know WHY it is the way it is, but have not been able to find an explanation, so here is what I came up with, submitted for your consideration/correction.In my possibly delusional understanding;The water out from the cooler goes to the torch water line with the 5/8" LH fitting. The water at its coldest goes through the torch head then is returned through the torch lead water line to the end of the Dinse connector with a 7/8 LH fitting. I assume this is to keep the torch lead cool as well, since the WP20 I have is rated at 250A yet has a smaller torch lead, and logically a conductor with less cross section, than a 150A WP17 torch. The Dinse connector passes the heated water exiting the torch and torch lead to a whip with a 5/8 LH fitting, and a LH to LH coupling is used to connect an extension hose (with LH fittings at both ends) to the return spigot of the water cooler.The gas hose from the torch connects with a RH fitting to the whip on the Dinse connector.The positioning of RH and LH fittings prevents connecting gas to water, etc.Since the return water hose from the torch is the torch lead as well, I guess teflon tape on the 7/8 LH fitting is out, huh?Is it normal to use teflon tape or paste on the other, non--current-carrying connections?Or do I have the whole thing mixed up?Regardless, it seems to me that the water passing through the torch head has the same voltage potential as the electrode, and so then does the entire water cooler. Makes me a little nervous, I know, electricity follows the path of least resistance, but I wonder what the potential for electrocution is in the event of a water leak... I assume that the work clamp is isolated from the welder chassis (ground)?JoeLast edited by scudzuki; 02-01-2012 at 06:07 PM.Miller Syncrowave 200Mac/Miller MW130 MIGKalamazoo bandsawCincinnati Arrow 500 VMCColchester Dominion 15 x 36 lathe with 2 axis DRO
Reply:The water lines are not dry seal anyway so teflon wouldn't work. They are a nut and ferrule and if the seat or ferrule is bad they leak. Teflon on the nut just makes it easy to split the female fitting and seat, then you're really screwed!Matt
Reply:You seem to have thae basics figured out. No tape on welding fittings. The coolant in the torch is not conductive enough and the arc voltage is not high enough to energize the whole coolant circuit.
Reply:@Matt,Now that I think about it, you are right, they are like a flange fitting, with straight threads. @welds,Thanks.JoeLast edited by scudzuki; 02-01-2012 at 08:39 PM.Miller Syncrowave 200Mac/Miller MW130 MIGKalamazoo bandsawCincinnati Arrow 500 VMCColchester Dominion 15 x 36 lathe with 2 axis DRO
Reply:Cool water is first sent to the heat source, then returned though the power lead. This allows for the power lead to be much more flexible and lighter weight than an air cooled torch because less copper can be used since it's cooled. Tig welding arc voltage is under 20volts, it's not enough to shock you. All the fittings seal with a taper, they don't use teflon tape or any sealant.Last edited by MikeGyver; 02-01-2012 at 09:33 PM.Welding/Fab Pics: www.UtahWeld.com