Various plasma arc cutting process parameters directly affect the stability, cutting quality and effect of the cutting process. The main plasma arc cutting machine cutting specifications are briefly described as follows:
1.No-load voltage and arc column voltage Plasma cutting power supply must have a high enough no-load voltage to easily lead the arc and make the plasma arc burn stably. The no-load voltage is generally 120-600V, while the arc column voltage is generally half of the no-load voltage. Increasing the arc column voltage can significantly increase the power of the plasma arc, thereby increasing the cutting speed and cutting larger thickness of the metal plate. The arc column voltage is often achieved by adjusting the gas flow and increasing the internal shrinkage of the electrode, but the arc column voltage cannot exceed 65% of the no-load voltage, otherwise the plasma arc will be unstable.
2. Cutting current Increasing the cutting current can also increase the power of the plasma arc, but it is limited by the maximum allowable current, otherwise it will make the plasma arc column thicker, the width of the cut seam increases, and the electrode life decreases.
3. Gas flow Increasing the gas flow can not only increase the arc column voltage, but also enhance the compression of the arc column and make the plasma arc energy more concentrated and the jet force stronger, so that the cutting speed and quality can be improved. However, the gas flow is too large, but it will make the arc column shorter, the loss of heat increases, and the cutting ability is weakened until the cutting process cannot be carried out normally.
4. The amount of electrode shrinkage The so-called internal shrinkage refers to the distance from the electrode to the end surface of the cutting nozzle, and the appropriate distance can make the arc well compressed in the cutting nozzle, and obtain a plasma arc with concentrated energy and high temperature for effective cutting. Too large or too small a distance will cause severe burnout of the electrode, burnout of the cutter and a decrease in cutting capacity. The amount of internal shrinkage is generally 8-11mm.
5. Cut nozzle height The cut nozzle height refers to the distance from the end of the cut nozzle to the surface of the cut workpiece. The distance is generally 4 to 10 mm. It is the same as the internal shrinkage of the electrode, the distance should be suitable to give full play to the cutting efficiency of the plasma arc, otherwise the cutting efficiency and cutting quality will be reduced or the cutting nozzle will burn out.
6. Cutting speed The above factors directly affect the compression effect of the plasma arc, that is, the temperature and energy density of the plasma arc, and the high temperature and high energy of the plasma arc determine the cutting speed, so the above factors are related to the cutting speed. Under the premise of ensuring the quality of cutting, the cutting speed should be increased as much as possible. This not only increases productivity, but also reduces the amount of deformation of the cut part and the thermally affected area of the cut area. If the cutting speed is not suitable, the effect is reversed, and the sticky slag will increase and the cutting quality will decrease.
1. The lower part of plasma cutting should be set up with a sink, and the cutting part should be cut underwater during the cutting process to avoid the poisoning of the human body by generating flue gas
2. Avoid direct visual vision of the plasma arc during the plasma arc cutting process, and wear professional protective glasses and face masks to avoid burns to the eyes and welding helmet by the arc.
3. A large amount of toxic gases will be generated during the plasma arc cutting process, which requires ventilation and wearing a multi-layer filtered dust mask.
4. In the plasma arc cutting process, it is necessary to wear towels, gloves, foot sheaths and other labor protective equipment to prevent the burning of the skin by the splashing mars.5. In the plasma arc cutting process, the high frequency and electromagnetic radiation generated by the high-frequency oscillator will cause damage to the body, and some long-term practitioners even have symptoms of infertility, although the medical community and the industry are still inconclusive, but they still need to do a good job of protection.
Post time: May-19-2022