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QZ——250潜孔钻机是在1973年年初由我厂与鞍钢矿山研究所联合设计的。该机由电机驱动,履带自行,它具有孔径大,自带空
QZ - 250 DTH drilling rig was jointly designed by our factory and Anshan Iron and Steel Institute of Mining in early 1973. The machine driven by a motor, track its own, it has a large aperture, comes with empty