| 摘要 |
Rock drill bit of the impact type comprising a cylindrical body and a front surface provided with fixed peripherally spaced inserts. The head section of each insert comprises a first and a second working surface. The first working surface is arched in the radial direction of the rock drill bit but planar in a direction perpendicular thereto. The second working surface is quarter-spherical and turned towards the center of the rock drill bit. A transition portion extends between the first working surface and the jacket surface of the insert. The transition portion determines the diameter of the bore. |
