US Patent 11185933 Drill body and drill

A drill body and a drill are disclosed. The drill body has a rotational axis and comprises a central chip flute extending along a periphery of the drill body. A central chip flute cross-section has a centre line extending in a plane extending perpendicularly to the rotational axis, and through the rotational axis. The central chip flute cross-section has a depth, as seen along the centre line, and a width as seen perpendicularly to the centre line. The central chip flute cross-section has a maximum depth Dp within a range of Dp=0.75×D/2 to Dp=0.90×D/2, and a maximum width W within a range of W=0.75×D/2 to W=0.90×D/2, and wherein the maximum width W extends symmetrically about the centre line.