Disassembling and assembling tool and method for locking round nut of thrust disc of oil-free screw compressor

The invention discloses a disassembling and assembling tool and a disassembling and assembling method for a locking round nut of a thrust disc of an oil-free screw compressor. The disassembling and assembling tool for the locking round nut of the thrust disc of the oil-free screw compressor comprises a round nut sleeve, a fixed torque wrench, a torque multiplier and a blocking component. The round nut sleeve is used for being arranged outside a locking round nut of the thrust disc in a sleeving mode and connected with the locking round nut so as to drive the locking round nut to rotate. The torque multiplier is provided with a torque input end, a torque output end and a counter-force arm, the torque input end is used for being connected with the fixed torque wrench, and the torque output end is used for being connected with the round nut sleeve so as to transmit torque to the round nut sleeve; the blocking component comprises a flange ring and a counter-force arm blocking rod, the bottom of the counter-force