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玩弄少妇高潮ⅹxxxyw,香蕉视频在线观看亚洲,色一情一乱一伦一区二区三区日本,日韩乱码人妻无码中文字幕久久,水蜜桃亚洲一二三四在线,五月丁香六月综合av,乱中年女人伦av二区,国产精品无码人妻一区二区在线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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