Plasma Arc Welding

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I love doing it. Any of you guys have much experiance in it?
Reply:Never have seen it done. Do you have any pics or video of it??? Thanks, Paul.And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.
Reply:No i don't but i could try to get some tomro
Reply:Plasma welding is a vairation of the TIG process and it is a piece of art, but the equipment is some what more expensive.  I have sold many and welded with them.  JohnSMAW,GMAW,FCAW,GTAW,SAW,PAC/PAW/OFCand Shielding Gases.  There all here. :
Reply:I worked with automated plasma welding for six years.  Between myself and a couple other engineers, and a bunch of technicians, we supported 25 systems.  Each machine would produce around 150 to 180 welds per hour, 18 hours a day.  The welds were fusion, no wire, on cylindrical parts about 3/4 to 1-1/2 inch diameter.The benefit of plasma for automated welding is that there is always a small (10 amp) pilot arc present between the tungsten and the copper orifice tip, so the main welding arc can be instantly initiated between the tungsten and the workpiece, without needing high frequency.  Weld after weld, after weld, can be made without having to ever "shut off" the arc.The pilot arc and the welding arc each have their own power supply.  And there are two gas flows through the torch, one is plasma gas which flows past the tungsten and through the orifice tip, and the other is shield gas which flows around the orifice tip, through an outer shield cup.  We used argon for plasma and shield gas.The orifice size, the distance from the orifice tip to the tungsten, and the gas flow rate will all affect the concentration of the welding arc.  We ran plasma in the conduction mode, just like TIG, but plasma can be setup for "key hole" full penetration welding through sheet materials.In a properly maintained system the tungsten electrode will last through several hours of welding, making an 8 second weld every 10 seconds or so.  The Thermal Dynamics 4A torch uses a 3/16" diameter electrode, and we used thousands of them.  We changed electrodes about every 700 welds, and send the used ones out to be remachined. Attached Images
Reply:Thanks pulsar, I didn't know squat about plasma welding.  Now I know a little DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:I think Plasma Arc Welding is one of the most under utilized processes used. It has it's advantages over TIG and Lasers. Especially the non transferred arc which operates from .1 amps to 10 amps. The non transferred arc is established between the - tungsten electrode and the + constricting tip. This makes it nice because the piece being welded doesn't need to be part of the welding circut. It beats tig in that you can weld into deep holes easier because when  you pull the arc gap longer the arc voltage only slightly drops unlike tig.
Reply:Originally Posted by David RThanks pulsar, I didn't know squat about plasma welding.  Now I know a little David
Reply:Rojodiablo, PAW is almost always done with automated systems in commercial environments.  And as far as I know you can run it off any standard TIG power source but the equipment you add-on is different.  Similar, but different.  It is also quite expensive.
Reply:Originally Posted by WelderBoyRojodiablo, PAW is almost always done with automated systems in commercial environments.  And as far as I know you can run it off any standard TIG power source but the equipment you add-on is different.  Similar, but different.  It is also quite expensive.
Reply:Wow Pulsar, That was very intersting and easy read. I never even new this type of welding exsisted.Thanks for the info.Miller DVI2Lincoln Precision Tig 225Thermodynamics Cutmaster 38Everything else needed.
Reply:The plasma system I used has a standard 300 amp, constant current, DC power supply for the welding arc, that can be used for Stick and TIG as well.  The pilot arc for Plasma however, requires a separate power supply, which in this case also houses gas flow controls.On some plasma systems, like the Thermal Arc Ultima 150, both the pilot ar and weld power supplies come in one unit, along with flow meters and water cooling.  http://www.thermadyne.com/uplFiles/l...0TSB%202.6.pdf
Reply:any one know about therma dyne ultima 150 machine?...is it possible to use tig torches with this machine?could you please guide?
Reply:I did VPPA for about 11 years. Just like anything else, you get bored with it after a couple of miles.Two turn tables and a microphone.
Reply:Originally Posted by shankarsreekumarany one know about therma dyne ultima 150 machine?...is it possible to use tig torches with this machine?could you please guide?