gas pressure issues

[Hub Steel]

I am running a Hypertherm 400XD autogas on a five axis robot. Today we had an operator come to us with about 3 or 4 burned up shield caps and sets of 260 amp consumables. he was concerned that we were burning up consumables after about 150 pierces when cutting 3/4 mild steel which is about 1/4 of the consumable life we normally get.

We are running 02/Air process mild steel cutting at 260 amp. I ran a gas check to see what kind of pressures we were getting in preflow and cutflow. I noticed that the plasma gas was getting to a good PSI in preflow and cutflow but the shield gas was shy by about 15 PSI of where it was supposed to get to. I ran the leak tests and didn't get any errors. I swapped out Berkert valves in metering console and got no results. The only thing I had success with was stepping down to 130 amp consumables from 260. I assume these consumables require less air so the shield gas gets to the PSI its expected to.

Any ideas of where to look next. I plan on watching the regulator in the morning to see how it is holding during cuts. I read on a hypertherm article that if you are burning up consumbles too fast and aren't getting good gas flows then you might see the nozzle get fused to the shield cap. (this was something that I did see so I assume I'm on the right track to finding the issue here).

Any input? where might I look for leaks or issues? new regulator? My regulator was reading 120 PSI at the machine. Like I said I failed to watch the regulator during a cut to see if it dropped out.

[jimcolt]

Hypertherm technical service is the best place for help on this high definition class plasma. technical.service@hypertherm.com or 1 800 643 9878 . Jim Colt Hypertherm