| 摘要 |
A blasthole drill comprising a frame supported for movement over the ground, a mast supported by the frame for movement relative thereto between a substantially vertical position and a non-vertical position, the mast defining a drill hole axis, a drill-through pipe rack mounted on the mast, the pipe rack including a rack member, a gate mounted on the rack member, the gate having open and closed modes and being adapted to support the lower end of a drill pipe when the gate is in the closed mode, the gate permitting the drill pipe to move downwardly relative to the gate when the gate switches to the open mode, and the gate allowing movement of the rack member away from a drill pipe previously supported by the gate when the gate is in the open mode, a mechanism for moving the rack member horizontally relative to the mast and between an extended position wherein a drill pipe supported by the gate is on the drill hole axis and a retracted position wherein the gate is spaced from a drill pipe on the drill hole axis, and a rotary head moveable relative to the mast along the drill hole axis, the rotary head being selectively engageable with the upper end of a drill pipe supported by the pipe rack when the rack member is in the extended position. |
