plasma pipe beveling

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has anyone here converted 1 of the trolley used for o/a to bevel and cut, I am in the market for 1 and was looking on ebay and there are 2 different ones made in China of course for o/a heads and was wondering and thinking ot lowed here that they should work.  Anyone have any input or success stories.ThanksRon Padilla
Reply:I have used a matthey dearman pipe band crawler and a Miller spectrum 80amp plasma ,with a machine torch, for beveling pipe.  I've cut large OD pipe this way; 36" and 42"; 1/2" and 5/8" wall thickness.  Straight cuts and 30° bevels.http://www.mathey.com/documents/Mona...achine_000.pdfYou need one of the optional attachements to hold the machine torch.  The crawler I used had the motor drive.  I'd think the hand crank version would be a pain in the butt to use, since the arc would tend to go out if you stop cutting for any length of time.When everything is dialed in the plasma bevels great and isn't as sensitive to changes in travel speed and tip to pipe distance as an oxy acetylene torch can be.  Doesn't leave as much dross/slag imbedded in the face of the bevel.  Seems to me to cut a truer edge, no rounding of the bevel surface.  I'm not a pro with a oxy-acetylene torch, so it may be my (lack of)skills that make the oxy-acetylene cuts lower quality...Doesn't really cut any faster than an oxy-acetylene torch that's setup right with the proper tip size.Be wary of cutting bevels with a plasma.  It's easy to exceed the rated cut capacity of the machine, if you're not careful.  Cutting big pipe with a plasma tears up consumables at an alarming rate.  Might be poor quality air, but the duty cycle for your torch and power supply needs to be 100% to cut large OD pipe.  Otherwise figure on replacing consumables every 2-3 cuts.  They last longer if you stop halfway and let the torch take a break for a couple minutes.Works good in a shop environment, but I have doubts about field use...Takes a lot of 220 3 phase power to run the right size plasma cutter.  Need a safe place to attach a ground clamp for the plasma, and I've seen arc strikes around the clamp if the metal wasn't bright, shiny, clean.Lots of air and power cables to manage.  I think these would be a hassle in the field.  Just more stuff to trip over and accidentally cut/damage.Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:Thanks for the reply I have looked at these as well as some others and my thought is that most wold be adaptable to most torch heads.Thanks again.