OPERATION 4-12 Manual 0-4691
4
C. Piercing With Machine Torch
To pierce with a machine torch, the arc should be started with the torch positioned as high as possible above the
plate while allowing the arc to transfer and pierce. This standoff helps avoid having molten metal blow back
onto the front end of the torch.
When operating with a cutting machine, a pierce or dwell time is required. Torch travel should not be enabled until the arc
penetrates the bottom of the plate. As motion begins, torch standoff should be reduced to the recommended 1/8 - 1/4 inch (3-
6 mm) distance for optimum speed and cut quality. Clean spatter and scale from the shield cup and the tip as soon as possible.
Spraying or dipping the shield cup in anti - spatter compound will minimize the amount of scale which adheres to it.
4.07 Cutting Parameters
Cutting speed depends on material, thickness, and other factors. These may have an impact on system performance:
• Torch parts wear
• Air quality
• Line voltage fluctuations
• Torch standoff height
• Proper work cable connection
To Next Page
Loading...
