<p>A method for drilling hard material such as rock by fragmenting the rock by impact in selected spaced-apart areas and simultaneously fragmenting the rock by shear between the selected areas. The invention also covers a drill head with particularly arranged impact hammers for carrying out the method, and a drill unit incorporating the drill head.</p>
申请公布号
CA1133954(A)
申请公布日期
1982.10.19
申请号
CA19800367024
申请日期
1980.12.17
申请人
MASSE, ROGER, 131, RUE ROUSSIN, THETFORD MINES, P.Q. G6G 1N6
发明人
MASSE, ROGER, 131, RUE ROUSSIN, THETFORD MINES, P.Q. G6G 1N6
