CNC cutting machine plasma power supply stability of a direct impact on cutting quality, if the plasma arc instability, it will lead to uneven incision, tumor and other defects, can also lead to control system components related to life expectancy, frequent replacement of nozzles, electrodes. Plasma power does not arc mainly due to high pressure, low pressure, poor ground contact with the workpiece, cutting torch nozzle and the electrode burning, the spark generator can not automatically broken arc, the input AC voltage is too low and other reasons. First of all, we must also make clear what we are using a plasma power supply, such as Kelby, Hypertherm, OTC, or Pegasus, if you can still think of, in fact, can cause improper assembly of plasma power Arc it? My unit technical staff after some research and analysis, based on many years of experience summed up the plasma cutting machine can not afford to arcing typical causes and solutions:
1. The pressure is too high
If the input air pressure far exceeds 0.45MPa, after the plasma arc is formed, the excessive air flow will blow away the concentrated arc column, which will disperse the arc column energy and weaken the plasma arc cutting intensity. Causes of over pressure are: improper input air conditioning, air filter regulator is too high or air filter regulator failure.
Solution: Check the air compressor pressure is adjusted properly, air compressor and air filter pressure regulator is out of order. After power on, such as rotary air filter regulator valve switch, gauge pressure unchanged, indicating the air filter valve failure, need to be replaced.
2. The pressure is too low
Plasma cutting machine work, such as working pressure is much lower than the instructions required pressure, which means that plasma arc discharge speed weakened, the input air flow less than the specified value, at this time can not form a high-energy, high-speed plasma arc, Resulting in poor quality incision, impermeable, incision tumor phenomenon. The reasons for the lack of pressure: lack of air compressor input air, cutting machine air regulator valve is too low, there is oil in the solenoid valve, the gas is not smooth and so on.
Solution: observe the use of air compressor output pressure before use, if not meet the requirements, adjust the pressure or overhaul air compressor. If the input pressure has reached the requirement, check the air filter regulator valve is correct, gauge pressure display can meet the cutting requirements. Otherwise, the air filter regulator should be routinely maintained to ensure that the input air is dry and free of oil. If the input air quality is poor, it will cause oil in the solenoid valve, the valve core is difficult to open and the valve port can not be fully opened. In addition, cutting torch nozzle pressure is too low, the need to replace the solenoid valve; gas cross section smaller will result in low pressure, according to the instructions required to replace the trachea.
3. Poor ground contact with the workpiece
Grounding is an essential preparation before cutting. Not using a dedicated grounding tool, the workpiece surface insulation and long-term use of aging ground, etc., will make the ground and the workpiece in poor contact.
Solution: Use a special grounding tool, and check whether there is insulation affect the ground contact with the surface of the workpiece, to avoid the use of aging grounding wire.
4. Torch nozzle and electrode burnout
Due to improper installation of the nozzle, such as the thread is not tight, equipment, gear adjustment properly, the need to use water-cooled torch at work, not required to access the flow of cooling water and frequent arcing, will cause premature nozzle damage.
Solution: In accordance with the technical requirements of cutting the workpiece, the correct equipment, gear, check the torch nozzle is installed jail, need to pass the cooling water nozzle should make the cooling water in advance. When cutting, adjust the distance between the torch and the workpiece according to the thickness of the workpiece.