EDM milling technology, also known as EDM generating processing technology, is a new technology that replaces traditional cavity processing with special-shaped electrodes. It is a simple high-speed rotating tubular electrode, which is used for three-dimensional or two-dimensional contour machining (like CNC milling), so it is no longer necessary to manufacture electrodes with complex shapes, which is obviously a major development in the field of EDM. Machine tools using this technology have been applied to mold processing abroad. It is expected that this technology will be developed. In the process of EDM, gas, metal chips and carbon black will be produced continuously. If it is not eliminated in time, it is difficult to deal with it stably. Poor machining stability will reduce pulse utilization and machining speed. In order to facilitate chip removal, oil washing (or pumping) and electrode lifting are generally used. In machining, for the cavity with shallow workpiece cavity or easy chip removal, auxiliary chip removal measures may not be taken. However, for the machining with difficult chip removal, if the oil is not flushed (pumped) or the pressure of oil flushing (pumped) is too low, the chances of secondary discharge caused by poor chip removal will increase obviously, resulting in a decrease in machining speed; However, if the oil flushing pressure is too high, the processing speed will also decrease. This is because the oil flushing pressure is too high, which causes interference and makes the machining stability worse, so the machining speed will decrease. In order to quickly eliminate the corrosion products in the discharge gap, in addition to flushing (pumping) oil, it is necessary to lift the electrode frequently to facilitate chip removal.