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国产成人亚洲精品无码影院bt ,国产精品 精品国内自产拍,国产精品高潮呻吟av久久黄,亚洲色成人网站永久,国产无套白浆视频在线观看 ,国产交换配乱婬视频偷网站,色欲久久九色一区二区三区,亚洲色欲av无码成人专区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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