The spindle device is not only the working mechanism of the hoist, but also the main bearing component of the hoist. It undertakes all the torque of the hoist as a winding hoisting steel wire rope to bear various loads. It is mainly composed of main shaft, bearing, bearing seat, drum, supporting wheel, lining plate, high-strength bolt assembly and other parts. The main shaft is forged with 45# carbon steel. After two NDT and mechanical performance tests, it meets the national standards and ensures reliable service performance. Except for the connection part with the coupling, there is no additional keyway on the main shaft, which not only ensures its strength but also ensures the rigidity of the main shaft, greatly improves the safety and prolongs the service life of the main shaft; The main shaft bearing adopts domestic ha, WA and Luo bearings, which can operate reliably and improve the rotation efficiency.