| 摘要 |
The invention relates to a drill body intended for chip removing machining having a front head (4) that includes two cutting edges, each one of which comprises two part edges (9, 10), a first one of which is included in a central tip part (8) having a front chisel edge (29), and the second one extends between a peripheral end point (11) and a radially inner end point (12), where the same transforms into the first part edge. In a primary clearance surface (13) two part surfaces (13a, 13b) are included, which meet each other in a chute bottom (17). According to the invention, the drill body includes not only a first chute bottom (17) between the two part surfaces (13a, 13b) of the primary clearance surface (13), but also a second chute bottom (30), which extends in the extension of the first one and separates two second part surfaces (15a, 15b) included in a secondary clearance surface (15). |
