| 摘要 |
The drill (1) has a shaft area (2) for clamping the drill, and a drill head (6) with a cutting part made of hard material, where the drill head has three spiral-shaped grooves (12). The grooves are formed by cold forming and/or hot forming of a wire section in a forming matrix of a forming machine, where two of the grooves have different cross sections and depths and bars (16) of different external diameters. The shaft area corresponds to DIN 3126standard and is formed as a SDS plus(RTM: portable power tool) insertion end. An independent claim is also included for a method for manufacturing a three spiral drill. |
