Regarding the adjustment of the nozzle height of the plasma cutting machine:
The difference between the plasma CNC cutting machine and the flame cutting machine is that the plasma cutting machine completes the control and cutting through voltage arcing. Then the nozzle height adjustment of the plasma cutting torch directly affects the processing effect of the workpiece. Usually, the nozzle height refers to the nozzle end face. The distance from the cutting surface, which forms part of the overall arc length. Since plasma arc cutting generally uses a power supply with constant current or abrupt drop characteristics, after the nozzle height is increased, the current change is small, but the arc length will increase and the arc voltage will increase, and the CNC cutting machine will increase the arc power; but at the same time It will also increase the arc length exposed to the environment, and the energy lost by the arc column will increase.
In the case of a combination of two factors:
1. The effect of the former is often completely offset by the latter. On the contrary, the flame cutting will reduce the effective cutting energy and reduce the cutting ability. Usually, the blowing force of the cutting jet is weakened, the residual slag at the lower part of the incision increases, and the upper edge is over-melted and rounded corners appear.
2. Considering the shape of the plasma jet, the diameter of the jet expands outward after leaving the muzzle, and the increase in the height of the nozzle of the cutting machine will inevitably lead to an increase in the width of the incision.
Therefore, choosing the smallest nozzle height as possible is beneficial to improve the cutting speed and cutting quality. However, when the nozzle height is too low, it may cause double arc phenomenon. Using a ceramic outer nozzle can set the nozzle height to zero, that is, the end face of the nozzle directly contacts the surface to be cut, and good results can be obtained.
