Machine tool spindle torque loading test system

The invention discloses a machine tool spindle torque loading test system which is used for testing reliability and loading performance under machine tool heavy load working conditions. The system comprises a supporting part, a measuring part, a loading part and a transferring part. The supporting part comprises a box body, a sensor support and a sensor adjusting gasket. The measuring part comprises a torque sensor and an accessory thereof. The loading part comprises a magnetic powder brake and an accessory thereof. The transferring part comprises a connecting head, a speed changing box and plum-blossom-shaped couplers. The speed changing box and a machine tool are connected through the connecting head. The speed changing box is arranged on a loader box body, then through the two plum-blossom-shaped couplers, the speed changing box is connected with the torque sensor, and the torque sensor is connected with the magnetic powder brake. During machine tool operation, brake torque generated by the magnetic powder brake is used for carrying out torque loading on a machine tool spindle, and real-time measuring is carried out through the torque sensor.