矿山冶金、原子能、船舶、飞机和电站等设备制造业是机械工业的主体。随着这些主体制造业规模的逐年扩大和产品品种的增加,对为其提供加工设备的机床工业提出了更高的要求,特别是要求提供机械化和自动化程度高的高效率大型机床。 一般地说,大型机床是按用户订货生产的。由于用 Mining and metallurgy, atomic energy, ships, aircraft and power plants and other equipment manufacturing industry is the main body of the machinery industry. With the gradual expansion of these major manufacturing industries and the increasing variety of products, higher requirements have been placed on the machine tool industry that provides them with processing equipment. In particular, it is required to provide a large-scale high-efficiency machine tool with high mechanization and automation. In general, large machine tools are ordered by the user. Due to use