PT-36 Mechanized Plasmarc Cutting Torch Instruction Manual

section 5Maintenance5.8 Reduced Consumable Life1. Cutting Up SkeletonsCutting skeletons (discarded material left after all pieces have been removed from a plate). Their removal fromthe table can adversely affect electrode life by:• Causing the torch to run off the work.• Continuous pilot arc edge starts.• Greatly increasing the start frequency. This is mainly a problem for O cutting and can be alleviated by2choosing a path with a minimum number of starts.• Increasing likelihood that the plate will spring up against the nozzle causing a double arc. This canbe mitigated by careful operator attention and by increasing standoff and reducing cutting speeds.If possible, use an OXWELD torch for skeleton cutting or operate the PT-36 at a high standoff.2. Height Control Problems• Torch diving is usually caused by a change in arc voltage when an automatic height control is used. Thevoltage change is usually the result of plate falling away from the arc. Disabling the height control andextinguishing the arc earlier when finishing the cut on a falling plate can effectively eliminate theseproblems.• Diving can also occur at the start if travel delay is excessive. This is more likely to occur with thin material.Reduce delay or disable the height control.• Diving can also be caused by a faulty height control.3. Piercing Standoff Too Low Increase pierce standoff4. Starting on edges withcontinuous pilot arcPosition torch more carefully or start on adjacent scrap material.5. Cut part tip up The nozzle may be damaged if the torch hits a flipped up part.6. Catching on Pierce Spatter Increase standoff or start with longer lead-in.7. Pierce not complete beforestartingIncrease initial delay time.8. Coolant flow rate low, Correct settingsPlasma gas flow rate high,Current set too high9. Coolant leaks in torch Repair leaks167