The Hydrodock clamping system is used as the clamping system for the machine tool interfacing with changing processing units. For example, these include milling heads and attachment spindles. Once the processing unit has been positioned on the machine, the clamping force is built up at the adapter ring by the segments being drawn in. The absolute self-locking feature of the system guarantees a high mechanical stability of the interface in connection with maximum safety. Therefore, no permanent pressure is required following the clamping process.