Parameter Setting Of Medium Wire Cutting Machine

Process requirements
Since the beginning of this century, several domestic electrical processing machine tool manufacturers have achieved multiple cutting processing on high-speed EDM wire cutting machines through the transformation of high-speed EDM wire cutting machines. This type of machine tool is called "medium wire" (the so-called "medium wire machine" does not only mean that the wire speed is between high speed and low speed, but also the processing quality is between high-speed wire machine and low-speed wire machine). Therefore, it can be said that the "medium wire machine" mentioned by users actually refers to those reciprocating wire EDM wire cutting machines that can achieve stripe-free cutting and multiple cutting. Multiple cutting technology can significantly improve the processing quality of high-speed wire cutting machines, solve the influence of material deformation during one cutting, improve processing accuracy, obtain lower surface roughness, eliminate reciprocating cutting stripes, and ensure a certain cutting speed. It has greatly improved the process level of high-speed EDM wire cutting, and because this type of machine tool has a high cost-effectiveness, it has gradually been accepted by a large number of small and medium-sized enterprise users. For "medium wire", the operating cost during use has not increased, but the cutting process indicators, especially the cutting surface roughness value, have been greatly reduced.
At present, the multiple cutting technology of high-speed wire cutting machines has made great progress, and the obvious improvement in processing quality has attracted the attention of many manufacturers and users. Although the surface finish of the workpiece is improved after multiple cutting of medium-speed wire EDM, the cutting accuracy of this type of machine tool is still far behind that of low-speed wire EDM machine tools, and the accuracy retention also needs to be further improved. The reason is that most "medium-speed wire" machines are improvements on the existing high-speed wire EDM machine wire feeding system, but their basic structure has not changed qualitatively; due to the repeated use of electrode wire, there will inevitably be electrode wire loss during the medium-speed wire cutting process, which affects the discharge gap and ultimately reduces the cutting accuracy; the medium-speed wire multiple cutting process has obvious processing effects for most terminal molds and stamping molds, and both the accuracy and roughness are significantly improved, and the operation is relatively simple. For punch processing, the processability is strong, and operating experience is very important. Some punch processing with large volume and thick materials still needs to accumulate processing experience. In addition, the differences and rules between theoretical corrections and actual corrections and the discharge mechanism of high-speed EDM wire cutting need to be further improved. Strictly produce according to the following conditions:
① Machine tool body: strictly control the manufacturing accuracy of the machine tool according to relevant national standards, especially improve the positioning accuracy and repeat positioning accuracy of the machine tool. At the same time, linear slides and precision screws imported from Taiwan or Japan are also used for pitch compensation or closed-loop control. Make the front and rear secondary cutting trajectories completely consistent;
② Wire feeding system: use a highly wear-resistant electrode wire holder to maintain the relative stability of the electrode wire, control the spatial shape and position changes of the electrode wire, and reduce the tension changes of the electrode wire during processing.
③ Pulse power supply: increase the cutting speed of one-time processing, stabilize it at more than 120 mm2/min., reduce electrode wire loss, ensure the accuracy of the workpiece, and provide a good performance finishing pulse power supply.
④ Frequency conversion servo: provides servo modes suitable for rough and fine processing to meet the processing requirements of different processing objects, and writes servo parameters into the processing parameter database in combination with electrical standards.
⑤ Cooling system: Change the commonly used extensive cooling method, adopt multi-level filtration and control key parameters such as dielectric constant to ensure the smooth progress of fine processing.
⑥ Control software: Provide an open processing parameter database, which can reasonably set the pulse parameters, processing trajectory compensation, electrode wire movement mode and movement speed of rough cutting, fine finishing and fine finishing according to the texture, thickness, roughness and other conditions of the material, and develop a corresponding multiple cutting intelligent database.
Although the processing quality has been significantly improved, the current cutting speed is still low and cannot meet the needs of users. We need to continue our efforts.