How does a plasma cutter work?
Metals can be separated with a plasma cutter. This is done primarily by cutting corresponding sheets from different metals. But metal cut-outs can also be made with a plasma cutter.
Functionality of a plasma cutter
Cutting with plasma cutters is done by an electric arc. This arc is generated when a high electrical voltage occurs between the two electrodes. One electrode in plasma cutting consists of the tungsten electrode and the power source required for this. The other electrode is then the material to be processed. High frequency ignition is caused by the ignition of the arc.
Insulated copper nozzles are normally used to constrict or focus the arc. However, there are also plasma cutters that also have a water-cooled copper nozzle. The insulation is very important, because otherwise the nozzles would not withstand the high temperatures.
The arc is constricted by the nozzle. In this way, the resulting plasma can condense. The compression results in an energy density that melts the metal at the point of impact. A gas jet removes the molten metal. In this way a cutting kerf can be created.
Use of different gases
Different gases are used. This depends on how clean the respective kerf must be. Mostly compressed air is used, but also inert gas mixtures. Compared to laser cutting, there are only slight differences in quality in precision cutting.
Advantages – Plasma cutters
Working with the plasma cutter brings some important advantages, such as
- The process is one of the most economical cutting processes in the steel sectorCuts thicknesses up to 35/40 millimetresRanks among the fastest thermal cutting processesPlasma cutting has less thermal influence than oxyfuel flame cutting Relatively little reworking is necessaryCuts oily surfaces, painted surfaces, rusty steel.
The gas plasma
Plasma is an ionised gas. It is, to a certain extent, inert. If it moves too fast, it can cause blurred edges. Plasma cutters are available as mechanically controlled devices or as manually operated devices. If the devices are manually controlled, high-quality cuts can be realized if the operator is experienced.