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国产乱子伦精品免费视频,中文字幕无码一二三,黄色免费在线网址,色女Av免费在线,亚洲一级色,在线国产欧美,国产亚洲精品自在线亚洲情侣,欧美国产视频The General Institute of Machinery Group independently develops and produces various engineering materials, including high quality welding materials, green surface protection materials, advanced die materials and composite materials.
The Group independently develops and produces a series of key parts, including high-end precision castings, gear transmission units, precision forming parts and so on.
The General Machinery Institute Group has been engaged in foundry, welding and cutting, plastic forming, heat treatment, surface treatment and other technical fields for many years. It can provide relevant technical services and equipment.
China Academy of Machinery Science and Technology (CAM), founded in 1956, is...
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