Tool and method for combined finish reaming of high-pressure compressor rotor

The invention discloses a tool and method for combined finish reaming of a high-pressure compressor rotor. The tool comprises a base plate, a cushion block, a first screw and a second screw. A supporting step is arranged on the top surface of the chassis; the cushion block is mounted at the position A of the inner wall of the top end of the middle drum; the first screw rod is used for being inserted into part of the combined bolt holes before finish reaming on each stage of disc ring from top to bottom; a threaded section at the lower end of the first screw rod is connected with a threaded hole in the cushion block; a threaded section at the upper end of the first screw rod is screwed with a first nut for pressing each stage of disc ring; the second screw rod is inserted into a finely reamed combined bolt hole in each stage of disc ring from top to bottom; a threaded section at the lower end of the second screw is used for being connected with a threaded hole in the cushion block; a threaded section at the up