Method and device for manufacturing a blank for a round tool

摘要

The present invention relates to a method and a device for manufacturing a blank for a round tool and to a blank (23) for a round tool, and eventually to a method for manufacturing a round tool and to a round tool (24) obtained. The device comprises a die (6) for extrusion and a sleeve arrangement comprising a sleeve (10), and an end member (14) for closing the sleeve (10) in one end. Extrusion through the die (6) continuously forms an extruded material (22) comprising chip flutes (4) and optionally internal coolant channels (3), which is received by the sleeve arrangement. The extruded material received by the sleeve arrangement is reworked and shaped to a shank portion (1) after the interior shape of the sleeve arrangement. A projection (15) of the end member (14) protruding into the sleeve (6) forms a bore (5) in the blank. When the shank portion is finished the end member (14) is released and moved forward as extrusion continues to form a fluted portion (2) to complete the blank. The material waste is minimal in this process and since the internal coolant channels (3) are formed simultaneously with the chip flutes in the fluted portion (2) there is no risk of deforming the internal coolant channels (3). Moreover, a bore (5) in the round tool (24) removes unnecessary material and provides improved design of internal coolant channels (3).