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英文原文 CNC Machining Process First, our country's history of the development of numerical control system 1. Our country since 1958, by a group of research institutes, colleges and universities and a few started to CNC Machine Tool Plant of the research and development system. At that time, due to the low level of domestic electronic components, such as the department of economic constraints, lack of a larger development. 2. In the reform and opening up, China's numerical control technology gradually achieve substantial development. After "65" (81 ---- 85 years) the introduction of foreign technology, "75" (86 ------ 90 years) of the digestion and absorption and the "Eighth Five-Year Plan" (91 ~ 1 -95 years) National Organization of scientific and technological, that makes our country's CNC technology has a qualitative leap in acceptance at that time, through research and identification of country products including Beijing Everest's Chinese I, central China's central NC I and a few high-end Shenyang National Engineering Research Center for Control of Blue-I, as well as other through the "National Quality Supervision and Test Center machine" test NC system of qualified domestic companies such as Nanjing, four products. 3. China's CNC machine tool manufacturing industry in the 80's had the stage of rapid development, many machine tool plant products from traditional products to the NC transition. But, generally speaking, the technological level is not high, the quality of the poor, so in the early 90's facing the country's economy from a planned economy to a market economy and adjust the transfer went through the most difficult years of the Depression period, the production capacity at that time dow...