Abstract: A device and a method are disclosed for centrally tightening rotatingly drivable parts. The device comprises at least three units for clamping and adjusting a part, wherein at least two of the units comprise an actuator allowing controlled adjustment in radial direction according to a control value. A measuring device is provided to detect deviations of the part from concentricity with respect to a rotary drive axis. A computer is used for controlling the actuators to effect concentricity of the part, the computer being responsive to deviations from concentricity detected by said measuring device.

Abstract: A chucking device for mounting a tool on a machine tool is provided, having a mounting section for mounting the chucking device on the machine tool and a thermally expandable shrink section which comprises a holding section intended to receive the tool in shrink-fit relationship. A lead-in section is provided at the outer end of the shrink section, whose inner diameter is selected to ensure that the shank of the tool can be placed in the lead-in section and can be centered therein in a cold condition of the shrink section. A suitable rotatably driven mounting intended to receive the chucking device during clamping of the tool is provided, preferably in vertical arrangement, in order to ensure that the shank of the tool will slide into the holding section from above under the action of gravity.