摘要 |
An axially elongated rock drill includes an axially extending shank and a drill head on one end of the shank. The drill head has a drill face extending transversely of the axial direction of the rock drill. A hard metal cutting plate and hard metal cutting pins are set in the drill face. The cutting pins reduce the wear on the cutting plate and afford better support of the drill. The cutting pins are arranged, in part, parallel to the axis of the drill, and, in part, inclined to the drill axis. The cutting plate has a cutting edge which generates a cutting plane as the drill is rotated with the ends of the cutting pins projecting from the drill face being located in the generated cutting plane.
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