Sat Mar 18 22:39:49 CST 2023
The following two main qualities are provided by the electrical pulses of plastic moulds.
A transient one-way pulsating discharge. Spark discharge must be a kind of pulse discharge that can be in the instantaneous, the discharge continues for a period of time after the need to stop for a period of time and then discharge, its discharge duration of about 10s. Because the discharge time is very short, so that the heat generated by the discharge is simply too late to conduct and spread to the inside of the processed material, so that the energy effect is limited to a small range of non-stop processing discharge, to maintain the cold pole characteristics of the spark discharge (i.e., the discharge channel energy conversion of heat can not be transmitted to the electrode depth or the inside of the processed material), not only to ensure the processing of its good precision and surface of the higher This ensures a good machining accuracy and a high surface quality of the machined part, without the intrinsic quality being affected by the pulsing electrode. In between the two successive pulse discharges there must be sufficient stopping time in order to avoid various arcing and local burns. Otherwise the surface of the mould core would be completely destroyed as in those cases where the arc discharge is continuously allowed. For this reason special pulse power supplies must be used for EDM.
In the case of injection moulding with an insulating liquid medium. EDM must be carried out in a liquid medium (i.e. working fluid) with certain insulating properties. The working fluids commonly used for our electrode processing are paraffin, spark oil, deionised water, etc. The requirements of the liquid medium must have a high insulating strength, in order to facilitate the generation of a certain pulsating spark discharge. At the same time, the liquid medium is required to enable the timely discharge of the galvanic corrosion products on the one hand, and to cool the workpiece on the other, so that the pulse discharge can be carried out smoothly. Only after the discharge of the galvanic products to the discharge channel outside, the repetitive pulse discharge can be processed smoothly. In the actual production situation of EDM, the discharge of galvanic corrosion products is mainly accomplished in two ways: on the one hand, the process of spark discharge and galvanic corrosion processing itself has the inherent characteristic of discharging the corrosion products, and the rest of the discharge products (e.g. vapour of the liquid medium) in addition to the corrosion products can also have the ability to facilitate the above process; on the other hand, it is also necessary to make good use of some artificial auxiliary On the other hand, it is also necessary to make good use of some artificial auxiliary measures, such as the filtration of the working fluid for circulation, some flushing and oil extraction measures used in the process, etc.
As long as the above two points are firmly grasped, the standard of the plastic mould electric pulse in the future will be greatly improved!