摘要 |
A replaceable cutter head for rotary percussion drills having a pilot cutter on the end of a drill stem with a main cutter head surrounding the pilot cutter, the main cutter head having hammering/chipping cutters and milling cutters arranged along radial lines extending from the pilot cutter to the outer periphery of the main cutter head in alternate arrays, either along the radial cutter lines or on alternate radial cutter lines, or both.
|