Railway rolling stock wheel box system due to the application of different conditions and the use of different structural design, locomotives, passenger cars have axle box, bearings through the axle box and the special direction of the frame connection, railway wagons do not have an axle box, bearings through the bearing broken saddle and the bogie side frame connection. The bearings bear the impact load generated between the wheelset and the bogie frame, and also bear the axle hub load generated by the vehicle rotation.

The structure of axle bearings includes round Gui Aozi bearings, the same column roller bearing unit tapered roller bearings, tapered roller bearing unit. According to the application requirements of railway bearings, the wheelbox sleeve bearing should have a long maintenance-free cycle, easy maintenance of the structural design and high re