Plasma Torch Height Control

Posted in CNC Plasma Tables

The Grip-Tech Plasma Torch height control system is an advanced Z axis control that enables our machines to cut all metals, even rusted or warped materials, equally accurately and ensure a consistently high cut quality with minimal or dross free cuts.

Commercially available metal sheet, especially thin sheet metal, is cut from rolled coils, transported by truck and man-handled so that it is not perfectly flat when delivered to your site.The sheets have residual curvature, warped corners and surface rust, etc. Partially cut sheets (not cut on our water-table based machines) will also have uneven surfaces due to heat distortion created by prior cutting.The surface height will vary across the sheet when placed on the plasma table, resulting in poor quality cuts and even torch failure.

The Grip-Tech Torch Height Control System performs two important functions;

1. Automatic Surface Sensing and Pierce Height Control

    The Grip-Tech THC initially senses and references the surface at the start of the cutting program and whenever piercing occurs at a distance from the previous reference point (user pre-set eg every 50mm). This saves time by ensuring that accurate pierce height is maintained on warped metal without needless sensing on flat surfaces. The torch height control probes the material by mechanically touching the material, sensing and zeroing to the surface height, and then retracting to the correct pierce height above the surface. This method is superior to electrical grounding as it removes the risk of miss detection due to surface scale, paint etc, and eliminates the need for a ground wire at the nozzle that may risk the arc jumping and damaging the control system.

2. Automatic Cut Height Control

    The automatic torch height controller maintains the correct height over the metal surface during actual cutting by monitoring the arc voltage from the plasma cutter. It automatically adjusts the height many times a second by comparing the cutting voltage to a user preset reference as well as the type of path being cut. New electronics and software now allow the required voltage and current to be set and monitored in our software.

The Grip-Tech THC is indispensable for superior plasma cutting. Users can easily adjust several parameters to optimise cutting speeds and prolong the life of torch consumables. The system can also be over-ridden when cutting mesh or similar materials.