Optimizing your Plasma Arc Welding Equipment
Wednesday, February 27th, 2008We have several large industrial corporations that we supply Plasma Arc Welding (PAW) torches and replacement parts to. One of them came to us for some help resolving inconsistent welds on a Thermal Arc® Ultima 150 Plasma Arc Welding machine with a 4A PAW torch and lead assembly. They were frustrated and had tried many different solutions from a variety of sources. I went through our basic PAW check list (which you can find in the Arc-Zone.com Welding Library– “Optimize Your Plasma Arc Welding Torch”). We did find two areas to improve, but the issue was still there. That’s when I asked “when was the last time you changed your lead set?”
“We just changed torches, we do that pretty often,” he said. “Why would we need to change the leads?”
With Plasma Arc Welding there are two important things to consider:
1. Plasma Arc Welding Torch Lifespan.
PAW torches have a life span of about three months. Now anybody that is familiar with automated TIG applications can’t understand why Plasma Arc Torches fail so often. There is no easy answer, but it is a characteristic of Plasma Physics. There are many more things going on inside that PAW torch than in a TIG torch — two power circuits, two gas distribution and flow paths, two water channels, tungsten electrode insulators etc. Bottom line is you should always have a spare Plasma Arc Welding torch on hand because when they fail they are junk. You’ll have no warning, and you’ll be down until you get it replaced.
2. The Lead Set
I call them leads because they consist of multiple hoses and cables inside a jacketed cover. And they wear out. Operators often don’t think to add the leads to their preventative maintenance schedules but they should.
Whether you’re doing PAW (plasma arc welding), or TIG/GTAW (gas tungsten arc) welding, there’s a lot of confusion about what kind of tungsten to use. At Arc-Zone.com we’ve put together a