Apparatus and method for rotary machining of rotors

A device for rotary machining of rotors, in particular rotors of gas turbines, on machining surfaces facing radially inward, wherein a rotor has at least two rotor disks which are in close proximity axially and have thick hub areas axially and central hub bores and are connected on an outside radially via projections, with a drill rod extending essentially in an axial direction and being held in a rotationally fixed manner and a tool mount holding a lathe tool and extending essentially radially, wherein the drill rod has a projection extending essentially radially and coupleable to the tool mount extending essentially radially, wherein radial dimensions of the projection of the drill rod and of the tool mount are adapted to a dimension of a hub bore of the rotor to be machined, such that the drill rod and the tool mount are insertable in an uncoupled state into the hub bore, and wherein, in a coupled state, the lathe tool mounted in the tool mount is abutable with a machining surface of the rotor facing radially inward, and wherein the lathe tool is movably mounted in the tool mount via a lathe tool holder, wherein the lathe tool is pivotable primarily axially together with the lathe tool holder with respect to the tool mount, and wherein a drive shaft is guided in the drill rod, and wherein the drive shaft is coupled to the lathe tool holder via a gear, wherein the gear converts a driving movement of the drive shaft into a pivoting movement of the lathe tool holder.