| 释义 |
line drilling line drilling[′līn ‚dril·iŋ] (mining engineering) The combined methods of drilling and broaching for the primary cut in quarrying; deep, closely spaced holes are drilled in a straight line by means of a reciprocating drill, and webs between holes are removed by a drill or a flat broaching tool. line drillingIn rock excavation by blasting, drilling a series of closely spaced holes, about 4 in. (10 cm) apart, at the perimeter of the cut, so as to break the rock along a line. |