Plasma jig for removing side bends

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Hello,I was wondering if anyone has ever used a plasma cutter to remove side bends from a welder qualification test pipe. I work as a welding examiner and we are trying to set up a jig to remove 4  3/8" wide side bend coupons from welder qualification tests on 2.375" and 2.5" OD pipe using the plasma cutter rather than the saw. Has anyone ever used plasma for this before? We have an idea of the jig we'd like to build, but if anyone has already found a design that works that would be awesome. Thanks!!!!
Reply:Being a plasma guy all my working life....I don't fully understand what exactly you are trying to do.....do you have pictures, drawings of the weld to be removed? I'd be happy to consult and maybe do some test cutting.Jim Colt   Hypertherm
Reply:It's pretty common on the gas lines to use a jig meant for an oxy-fuel torch. It would probably bit quite a  bit of work to adapt one unless your using a machine torch but the idea is the same.  I cant remember what they are called but im sure someone will chime in.Jim - He wants a jig that will make a good rectangle shaped cutout on a piece of pipe.Have we all gone mad?
Reply:Ok, apparently I wasn't very clear. When doing a welder qualification test in accordance with ASME IX, 4 transverse side bends must be removed from the test coupon. In this case the welds are done on 2.375" or 2.5" O.D. pipe. We must cut out a 3/8" wide section in each quadrant, running the length of the coupon (~10"), grind, and bend them in a testing jig. Currently, our machine shop removes the coupons with a band saw, which takes approximately 15 to 20 minutes. We intend to build a jig/positioner to use with a manual plasma torch so we can cut the coupons faster, and leave the saws free. We want to be able to run the torch along some type of guide to achieve straight, consistant, repeatable cuts, and be able to rotate the pipe within the assembly to access all four quadrants. If anyone has ever seen or used anything like this, please tell me about it. Thanks for your replies.
Reply:A number of manufacturers, including Thermal Dynamics, make straight line cutting guides for plasma torches.  Basically just a 4 foot track section with a pair of rollers, and you slide it along whatever it is you're cutting.
Reply:Consider mounting a horizontal rod or pipe with a vise-grip welded to it to hold the pipe section horizontal, and a simple steady rest like that used on wood lathes so the cut can be made manually. Rest and pipe clamp should be quickly adjustable without tools.Rollers won't do because they would stumble on the weld unless the rollers don't touch the pipe.As you "rotate" the pipe you will lose sections of pipe to cutting.A simple clamp would let you "cut and adjust x4" without regard to shape of remaining pipe.Last edited by farmall; 07-19-2011 at 12:25 PM.
Reply:I just set my piece of pipe in a piece of angle iron that is attached to the track torch table :] cuts the strips perfect every time
Reply:Thanks everyone for your replies