Wheel bearings are one of the key parts of the car, its main role is to carry the weight and provide an accurate guide for the rotation of the hub , which requires that it not only can withstand axial load also bear the radial load. Wheel bearing units is the standard angular contact ball bearings and tapered roller bearings developed on the basis of it as one of the two sets of bearings , having a good assembly performance , you can omit clearance adjustment , light weight, compact structure, large load capacity , the can be pre- loaded grease sealed bearings , hub seals and maintenance omitted from the external wheel , etc., have been widely used in cars , the truck also has a tendency to gradually expand the application .

The first generation wheel bearing is a double row angular contact bearing components.

The second generation wheel bearing have an outer raceway for the bearing retainer flange , the bearing sleeve may simply be fixed with a nut on the axle. Making the car maintenance becomes easy.

The third generation wheel hub bearing units are used bearing unit and anti-lock braking system ABS compatible . Wheel hub unit designed with inner flange and outer flange, bolted flange on the drive shaft , the entire outer flange bearings mounted together

The fourth generation hub bearing unit is the CVJ and bearing made of a whole, to solve the prior art because the hub and the constant velocity joint integrated structure makes wheel size increases caused by increased weight disadvantage . Features are: no need to adjust the bearing assembly clearance , bearing assembly process more rational, lighter volume decreases, disposable after use almost permanently fitted grease , reduced the overall cost of production, more conducive to the massive popularity