Precautions for Operating CNC Plasma Cutting Machine

The selection of cutting process parameters of CNC plasma cutting machine is crucial to the cutting effect such as cutting quality, cutting speed and efficiency. The correct use of CNC plasma cutting machine for high-quality fast cutting requires a deep understanding and learning of cutting process parameters.

Ⅰ. Arc voltage of CNC plasma cutting machine

It is generally considered that the normal output voltage of the power supply is the cutting voltage. CNC plasma cutting machines usually have higher no-load voltage and working voltage. When using gases with high ionization energy such as nitrogen, hydrogen or air, the voltage required to stabilize the plasma arc will be higher. When current-timing, an increase in voltage means an increase in arc enthalpy and an increase in cutting power. If the diameter of the jet is reduced and the flow rate of the gas is increased while the enthalpy value is increased, a faster cutting speed and better cutting quality can often be obtained.

Ⅱ. Cutting current of CNC plasma cutting machine

It is the most important cutting process parameter, which directly determines the thickness and speed of cutting, that is, cutting ability.

Affect:

1. The cutting current increases, the arc energy increases, the cutting ability increases, and the cutting speed increases accordingly;

2. The cutting current increases, the arc diameter increases, and the arc becomes thicker, making the incision wider;

3. If the cutting current is too large, the thermal load of the nozzle will increase, the nozzle will be damaged prematurely, and the cutting quality will naturally decline, and even normal cutting cannot be performed. Therefore, the cutting current and the corresponding nozzle should be correctly selected according to the thickness of the material before cutting by the CNC plasma cutting machine.

Ⅲ. Cutting speed of CNC plasma cutting machine

The optimal cutting speed range can be selected according to the equipment instructions or determined by experiments. Due to the thickness of the material, different materials, melting point, thermal conductivity and surface tension after melting, the cutting speed also changes accordingly.

main performance:

1. A moderate increase in the cutting speed can improve the quality of the incision, that is, the incision is slightly narrowed, the surface of the incision is smoother, and the deformation can be reduced.

2. The cutting speed is too fast, so that the cutting line energy is lower than the required value, and the jet in the slit cannot quickly blow off the melted cutting melt, resulting in a large amount of back drag. Surface quality declines.

3. When the cutting speed is too low, since the cutting place is the anode of the plasma arc, in order to maintain the stability of the arc itself, the anode spot or anode area must find a place for conducting current near the cutting seam closest to the arc, and at the same time, it will send the current to the jet. The radial direction of the incision transmits more heat, so the incision is widened, and the molten material on both sides of the incision gathers and solidifies at the bottom edge, forming slag that is not easy to clean, and the upper edge of the incision forms a corner due to excessive heating and melting.

4. When the speed is extremely low, the arc will even be extinguished due to the excessively wide incision. It can be seen that the good cutting quality of CNC plasma cutting machine is inseparable from the cutting speed.