| 摘要 |
Abstract A drill bit comprising a body having an outer surface, and at least one cutting element attached to the outer surface, wherein the cutting element is adapted for selective displacement between an extended condition and a contracted condition. There is also provided a drilling tool and a drill comprising a drill bit and a drive means for transferring rotary and/or percussive movement to the drill bit, the drill bit comprising a body having an outer surface, and a cutting element attached to the outer surface, wherein the cutting element is adapted for selective displacement between an extended condition and a contracted condition as well as a method for installing a rock bolt in a rock formation. |
