In the last eight years, developments in plasma cutting technology have come a long way. The latest revision on high-definition machines is their full integration with the CNC machines they are coupled with. New CNCs have touchscreen accessibility, minimizing the number of buttons involved in operating a plasma cutting machine and making operation as simple as almost any Windows®-based software. Operator training has been simplified on even the largest, most complex CNC plasma cutting machines.
Effective plasma power source design has also reduce input power requirement and also maximised the cutting thickness capacity of new generation plasma power source.
The operator’s job also has been made easier with improvements in auto-calibrating height control functionality. The operator does not need to make adjustments as the consumable parts in the torch wear out.
Introduction to True Hole Technology
Hole cutting has improved since the early days (top) of plasma cutting. Today’s plasma technology can deliver precisely cut holes that meet very tight specifications (bottom).
Hole cutting has been improved with a large database of information in the CAM software that automatically recognizes CAD features and implements the best possible cut path and plasma cutting parameters, including on-the-fly shield gas changes that nearly eliminate the normal taper found in plasma-cut holes on steel (see Figure 3). This process is transparent to the machine operator and system programmer, eliminating the need for them to be experts.
Improvements in cut-to-cut cycle times have been incorporated into CAM software. The software automatically recognizes areas of a full cutting nest (multiple parts) and modifies the traverse time, torch retract time, and gas preflow time to decrease production times and improve product throughput. Nesting software now applies the lead-in points in the most effective way to avoid traversing over areas prone to collisions with previously cut parts. Apart from this, optimising the number of piercing has also resulted high consumables life in turn low operating cost.
Improved plate beveling software has simplified the integration and operation of a bevel head with XY CNC cutting machines. This advancement, again associated with the system’s CAM software, saves much of the programmer/operator trial-and-error testing that has always been necessary to hold the best tolerances on plate edge beveling applications, such as weld prep.
Very new vented nozzle and gas mixing technology has helped improve stainless steel edge quality. Edges are squarer, shiny, and weldable.
Current control capability of the Plasma power source through CNC has resulted very fine arc control during the plasma cutting. Ramped up current and Ramped down current in Plasma power source are optimised to achieve the high cutting quality at the start and end of the profile.
Speed and acceleration of Gantry play major roll in achieving good cutting quality profile cut. Recent development of high speed gantry with high acceleration help to achieve the optimum cutting parameter at start and end the profile resulted to minimise cutting defect in profile.
Many other advances have been made to improve reliability, performance, consumable life, cut quality, and ease of use since the first plasma system was created. The process shares the cutting market with laser cutting, abrasive waterjet, and oxyfuel cutting, all of which deliver accuracy, productivity, and long-term cost-effectiveness when used for the appropriate applications.