- Oct 28, 2024
How to distinguish: WEDM-HS, WEDM-LS, WEDM-MS?
How to distinguish: WEDM-HS, WEDM-LS, WEDM-MS?
The "high", "low" and "medium" of WEDM-HS, WEDM-LS, WEDM-MS do not refer to the actual cutting speed during processing. It cannot be simply considered that WEDM-HS means the processing speed is fast, and WEDM-LS means the processing speed is slow. They are divided according to the different running speeds of brass wire (molybdenum wire). The earliest wire-cut EDM machines were divided into two categories based on the different running speeds of brass wire (molybdenum wire):
One type is high-speed wire-cutting EDM, referred to as WEDM-HS. The molybdenum wire reciprocates rapidly, and the general wire running speed is 8~10m/s. The electrode wire can be reused, and the cutting speed is slow. Moreover, fast wire running can easily cause the molybdenum wire to jitter and reverse streaks, which will reduce the processing quality. It is the main model produced and used in China, and it is also China’s original wire-cut EDM processing model.
The other type is low-speed wire-cutting EDM, referred to as WEDM-LS. The brass wire moves in one direction at a slow speed. Generally, the wire running speed is lower than 0.2m/s. The brass wire is no longer used after discharge. It works smoothly and evenly, with small jitter, good processing quality, and fast processing speed. It was the first machine tool developed by the former Soviet Union. Currently commonly used brands include: AgieCharmilles, Mitsubishi, Sodick, Fanuc, Seibu, SSG, Chmer, etc.
Machine tool performance comparison table for WEDM-HS, WEDM-LS, WEDM-MS
China's unique high-speed wire EDM machine tool has developed rapidly since it was successfully developed in the late 1960s due to its simple structure, lower cost and ability to meet general process requirements. It has now become the cheapest wire EDM equipment in the industry. However, because the processing quality problem has not been effectively solved, and with the continuous improvement of the technical level of low-speed wire cutting machine tools produced abroad, and the development of the mold industry. High-speed wire EDM machine tool has been unable to meet the needs of mold development.
In order to meet the needs of users, on the basis of retaining the characteristics of high-speed wire EDM machines such as simple structure and low cost, low-speed wire multiple cutting technology was introduced and a medium-speed wire EDM machine (WEDM-MS) capable of multiple cuttings was developed. This machine is more friendly and convenient than WEDM-HS machines, and has a wider range of applications. The "medium-speed wire cutting machine" independently developed and produced in China not only moves the moly wire between "high speed" and "low speed", but also has a processing quality higher than that of high-speed wire EDM machines and close to low-speed wire EDM machines. WEDM -MS machine tools also have relatively low cost of use.
1.2 The development direction of wire EDM machine tools
1.2.1 How was the wire EDM machine tool invented?
In 1870, British scientist Priestley first discovered the corrosive effect of electric discharge on metals. However, electric corrosion has been considered a harmful phenomenon for a long time. It was not until 1943 that Lazarenko and his wife, academicians of the Soviet Academy of Sciences, were studying the phenomenon and causes of corrosion damage to switch contacts by spark discharge, and discovered that the instantaneous high temperature of the spark could melt, oxidize and corrode local metal. Thus, the electric discharge machining method was pioneered and invented. The wire-cut electric discharge machine was also invented in the former Soviet Union in 1960.
1.2.2 The development of wire EDM machine tools in China
China has started experimental research on EDM since 1951, and has established a number of EDM research institutes and laboratories. In the early 1960s, the Institute of Electrical Engineering of the Chinese Academy of Sciences successfully developed our country's first wire-cut EDM machine tool that relied on imitating shapes. In 1963, Zhang Weiliang, an engineer at the Shanghai Electric Meter Factory, innovatively developed the first high-speed wire-cutting simple CNC wire-cutting prototype. He won the National Invention and Creation Award; From 1967 to 1968, Shanghai Fudan University and Shanghai Jiaotong Electrical Appliance Factory jointly developed the "Fudan type" high-speed wire EDM wire cutting machine tool, forming a unique type of wire cutting machine tool in China. It was the most widely used and widely used in production at that time. The largest number of CNC electrical machining machines.
In mid-1979, China established a national electrical machining society. In 1981, the Special Processing Teaching Research Association was established among universities in our country. This has greatly promoted the popularization and improvement of special processing. Due to China's vast territory and large population, there is both huge social demand and huge development potential for special processing technology in the process of industrial development. China's total number of special processing machine tools also ranks among the top in the world. Many scientific and technical personnels in China have won eight national invention awards in electric spark, ultrasonic, and electrochemical processing.
1.2.3 The development of low-speed wire EDM in China and internationally
Because the brass wire moves smoothly, the low-speed wire EDM machine tool can easily obtain higher processing accuracy and low surface roughness, so it is suitable for processing precision molds and high-precision parts. On the basis of introduction, digestion and absorption, China has also developed and mass-produced low-speed wire EDM machine tools, meeting some needs of the domestic market. It is now necessary to strengthen in-depth research on low-speed wire EDM machine tools, develop new specifications and varieties, and provide the market with more domestic low-speed wire EDM machine tools.
Electrical processing equipment manufacturing companies in Switzerland (AgieCharmilles) and Japan (Mitsubishi, Sodick, Fanuc, Seibu, etc.) are determined to win the low-speed wire EDM wire-cutting machine tool market in mainland China. They have completed localization of manufacturing, marketing, and R&D in mainland China, and they also have obvious technical and financial advantages.
Low-speed wire EDM machine tools in Taiwan China are also strong competitors, and they are relatively mature in technology. At present, manufacturers such as Chmer, ARD, Accutex, JSEDM, JOEMARS, MAXSEE and Sure First have been able to put into mass production.