The problem of wire breaking has always been a serious problem in the process of WEDM, which wastes a lot of working time. It makes the processing stop and has to start from the beginning, adding the difficulty of completing the unmanned processing. It has been an important topic in the research of wire cutting machine technology at home and abroad to discuss the causes of wire breaking and the methods to avoid wire breaking, so as to prevent the further development of wire cutting machine technology. The research shows that the precursor signals of different types of pulse power supply are different, and there will be a sudden addition before the wire breaking. For the amount that can reflect the input energy into the discharge gap, there are some foreign wire cutting machine tools adopting protective measures according to the precursor of wire breaking.
The reason of wire breaking of WEDM machine tool is that the heat load of the input gap is added and concentrated on one point. According to the signal of unstable processing process, and the cause is the instability of processing process, it is the fundamental way to overcome the problem of wire breaking, and adopt effective measures to make it quickly enter the stable state.
1. Cooling system when the cooling system on the wire cutting machine is not perfect, it can not enter the cutting seam, and the electrode wire can not be fully cooled. Before the practice of wire cutting machine, check whether the cooling system is perfect, which is easy to cause the electrode wire to be burned.
2. When processing, the coolant splashes around with the electrode wire movement, which is the key to affect the wire cutting machine tool processing. If it has loss, it will directly affect the processing accuracy. Pulse power supply is an important part of the wire cutting machine tool, and the pulse power supply of the WEDM machine tool should have the function of making the electrode wire low loss.
3. If the molybdenum wire device of the WEDM machine tool is too loose, and the vibration of the molybdenum wire directly affects the surface roughness of the workpiece, and the internal stress is increased due to the tightness. Therefore, during the cutting process of the molybdenum wire, the force should not be too large when tightening the wire. It should be confirmed that the connection of all parts of the machine tool is normal. However, the molybdenum wire can not be installed too tightly during the operation of the machine tool, so the operator needs to confirm the wire before use Safe starting of high pulse power supply for cutting machine tool.
