【建筑】钻 孔 器【运输】钻孔机械

铅球投掷训练器械轨道方程之研究

offshore drilling

drilling out (boring out)

measured drilling depth

slip-type elevators with deep-well drilling rods

drill (drilling, boring, borehole)

dowel hole drilling machine

surface drive for combined percussion and rotary drilling in deep drilling

offshore drilling platform