Development status and trend of the hottest high-s

Development status and trend of high-speed wire EDM

with the rapid development of social economy, the demand for high-speed wire EDM machine tools is also increasing. This paper mainly analyzes the current situation of wire cutting in China from the aspects of cutting efficiency, high thickness cutting and large taper cutting, and points out the future development direction of high-speed wire walking in order to enhance the competitiveness of high-speed wire walking

1. Introduction

high speed wire EDM technology uses electric energy to process the workpiece, rather than mechanical force. Therefore, high-speed wire walking can process any conductive material with hardness, strength and brittleness, which is not limited by material properties. It occupies a very important position in the field of machining and has a broad application prospect

2. Research status of high-speed wire EDM

2.1 cutting efficiency

high-speed wire EDM technology has been qualitatively improved in cutting efficiency than before. With intelligent pulse power supply and composite working fluid, the one-time cutting efficiency can reach 150-180mm2/min. At this time, the electrode wire loss is ≤ 0.01mm/200000 mm2, and the maximum processing efficiency can reach more than 250mm2/min. These indicators have been close to the general one-way wire cutting efficiency requirements, but because the operating cost of high-speed wire EDM machine tool is only one tenth of that of low-speed wire cutting, high-speed wire cutting has a very obvious advantage in comparison

2.2 high thickness cutting

due to the slow running speed, it is difficult to bring the working fluid into the machining gap solely by the speed of the electrode wire itself for cooling, deionization and impurity removal. Deionized water needs to be injected under high pressure. However, when the cutting thickness exceeds 200mm, it is difficult to bring deionized water into the discharge gap by high voltage, which greatly increases the probability of wire breakage, increases the production cost, and affects the subsequent production links. The working fluid of high-speed wire walking mainly depends on the high-speed moving electrode wire. The working fluid can easily enter the discharge gap for cooling, washing and deionization. Therefore, high-speed wire walking can cut high thickness or even ultra-high thickness. At present, the maximum cutting thickness of high-speed wire walking machine tools has exceeded 1000mm, and high-strength ultra thick steel plates for offshore exploration and oil production platforms with cutting thickness of more than 1500mm basically rely on foreign customized products

2.3 large taper cutting

taper cutting, as the name suggests, is that in the machining process, the electrode wire needs to be tilted at a certain angle, but it is very difficult for the low-speed wire EDM machine tool, because it needs to spray the working fluid into the tilted machining gap during the machining process, which is very difficult to implement. Therefore, when the workpiece is produced with a large taper of low-speed wire walking, it is very easy to cause the electrode wire to break and affect the subsequent production. However, high-speed wire walking mainly relies on the high-speed electrode wire to bring the working fluid into the processing gap to support the establishment of an authoritative, open and shared new material database, which is relatively easy to achieve large taper cutting. At present, the maximum cutting taper of high-speed wire walking has reached ± 45 ° based on the optimistic view of the lithium battery industry and consideration of the company's future development, and the advantage is quite obvious

2.4 realization of stable multiple cutting

in terms of machining accuracy and surface roughness, there is still a certain gap between high-speed wire walking and low-speed wire walking. If high-speed wire walking is used for multiple cutting of workpieces, the gap between them will be greatly reduced. At present, high-speed wire walking and multiple cutting have reached RA <0.8 μ m. The cutting accuracy is stable within 0.01mm, and the comprehensive efficiency of three times of cutting (cutting one and repairing two) can reach 80mm2/min, RA ＜ 1.2 μ m. The gap with low-speed wire walking is still small

2.5 service life of electrode wire

the service life of electrode wire is the key to high-speed wire walking to process workpieces efficiently, and it is the vitality of high-speed wire walking. At present, when the processing conditions are suitable, the plasticization performance of the dry mixture is improved. The cutting area can reach 900000mm2 with 300m wire feeding at one time, which is very considerable

3. Development trend of high-speed wire EDM

with the rapid development of economy and society, people have higher and higher requirements for product quality. Therefore, high-speed WEDM technology can not stand still, but also needs to be improved and developed in many aspects to meet the needs of all aspects and improve market competitiveness

3.1 higher machining surface quality

with the rapid development of economy, people have higher and higher requirements for the surface quality of high-speed wire walking processing, and the vibration of electrode wire in the processing process is an important reason for the poor surface quality. Therefore, the research and development of constant tension wire conveying system should be strengthened to reduce the vibration of electrode wire in the processing process and improve the surface quality of workpiece processed by high-speed wire walking

3.2 working fluid with better performance

high speed wire walking can carry out large thickness or even super thick cutting, which makes its advantages, but it also has higher requirements for working fluid. It is necessary to ensure that the cutting process is stable, with less environmental pollution and no harm to human body. Ceramic composite materials have been widely used in recent years, but when using high-speed wire walking for processing, the existing working fluid is not easy to flow in the processing process, and will adhere to the electrode wire, which will affect the elimination and deionization of electrocorrosion products, and it is easy to cause wire breakage and affect subsequent processing. Therefore, the development of working fluid suitable for these special materials will be imminent

3.3 green energy conservation

with the development of economy and the rapid increase of population, people's demand for energy is also increasing. Green energy conservation has become a new theme of world economic development. Therefore, it is necessary to carry out the research and development of new pulse power supply. Green energy conservation and environmental protection will be its necessary quality, which will inject new vitality into the rapid development of high-speed wire walking

3.4 ultra thick machining

in ultra thick machining, although high-speed wire walking has been able to process more than 1000mm workpieces, the machining process is unstable, resulting in poor machining accuracy and surface roughness. It is necessary to put more effort into the cutting of ultra thick workpieces above 600mm, so that they can be processed stably

3.5 gas processing technology

machining in air technology, as its name suggests, is machining in air. Compared with wire cutting EDM in working fluid, it has the characteristics of environmental protection and pollution-free in the machining process, no electrolytic corrosion on the machined surface, and good surface quality. Experts from Harbin University of technology have studied the gas processing technology and verified the feasibility of its operation through experiments. However, through experiments, we also found its defects, such as poor cooling effect by air cooling, no working fluid to take away chips, poor chip removal effect, resulting in slow processing speed. Therefore, how to improve the cooling effect and chip removal effect of gas processing technology will be the focus of the development of gas processing technology, which also plays an extremely important role in promoting the development of high-speed wire walking

4. Conclusion

this paper mainly introduces the current situation of high-speed WEDM technology in cutting efficiency and large taper cutting, as well as its development trend in cutting efficiency and machined surface quality. Through these, we can understand our shortcomings and future development direction, and expect to contribute to the development of WEDM Technology in the future