What are the factors that limit the cutting effect of Plasma Cutting Machine?
The cutting effect of the plasma cutting machine is good or bad, what factors determine the final cutting effect of the plasma cutting machine? Nanjing Claus summarizes the following factors for you.
1. No-load voltage and arc column voltage
The plasma cutting power supply must have a sufficiently high vacuum voltage in order to generate an arc and stabilize the plasma arc combustion. The vacuum voltage is usually between 120v and 600v, and the arc column voltage is usually half of the vacuum voltage. Increasing the arch column tension can significantly increase the power of the plasma arc, thereby increasing the cutting speed and cutting metal plates with greater thickness. The arc column voltage is usually not achieved by adjusting the gas flow and increasing the internal contraction of the electrode, but the arc column voltage cannot exceed 65% of the vacuum voltage, otherwise the plasma arc will be unstable.
2. Shear current
The increase of the shear current may also increase the power of the plasma arc, but subject to the allowable current, otherwise the plasma arc column will become thicker, the shear width will increase, and the electrode life will be shortened.
3. Air flow
The increase of the gas flow rate not only increases the voltage of the arc column, but also increases the compression effect of the arc, thereby increasing the energy concentration and spray force of the plasma arc, thereby improving the cutting speed and quality. However, excessive air flow may shorten the arch column, increase heat loss, and reduce the shearing capacity until the shearing process is successful.
4. Internal electrode removal
Soi (internal shrinkage) refers to the distance between the electrode and the end face of the cutting port. The appropriate distance makes the arc well compressed in the cutting port, and obtains a plasma arc with high energy concentration and high temperature to achieve effective cutting. If the distance is too large or too small, the electrode may be severely burned, the cutting nozzle may be burned, and the cutting ability may be reduced. The internal shrinkage is usually 8 to 11 mm.
5. Cutting height
The opening height is the distance between the opening surface and the curved surface of the cutting workpiece. The distance is usually 4 ~ 10mm. As with the internal removal of the electrode, the distance must be suitable to fully utilize the cutting efficiency of the plasma arc, otherwise the cutting efficiency and cutting quality may be reduced, or the cutting port may be burned.