Mechanized Plasmarc Cutting Torch - ESAB Welding & Cutting ...

section 5
Maintenance
5.8 Reduced Consumable Life
1. Cutting Up Skeletons
Cutting skeletons (discarded material left after all pieces have been removed from a plate). Their removal from
the 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 by
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choosing a path with a minimum number of starts.
• Increasing likelihood that the plate will spring up against the nozzle causing a double arc. This can
be 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. The
voltage change is usually the result of plate falling away from the arc. Disabling the height control and
extinguishing the arc earlier when finishing the cut on a falling plate can effectively eliminate these
problems.
• 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 standoff
4. Starting on edges with
continuous pilot arc
Position torch more carefully or start on adjacent scrap material.
5. Work Flipping 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 before
starting
Increase initial delay time.
8. Coolant flow rate low, Correct settings
Plasma gas flow rate high,
Current set too high
9. Coolant leaks in torch Repair leaks
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