Wheel bearing is one of the key parts of the car, its main role is to carry the weight and provide accurate guidance for the rotation of the wheel hub, which requires it not only to withstand the axial load but also to withstand the radial load.   Conventional bearings for automotive wheels are made up of a combination of two sets of tapered roller bearings or ball bearings, and the mounting, greasing, sealing, and clearance adjustment of the bearings are all carried out on the automotive production line.

Wheel hub bearing unit is developed on the basis of standard angular contact ball bearings and tapered roller bearings, it will be two sets of bearings as one, with good assembly performance, can omit clearance adjustment, light weight, compact structure, large load capacity, for sealed bearings can be loaded with grease in advance, omit the external hub seals and maintenance-free, etc., has been widely used in sedans, and also in the heavy-duty vehicles to gradually expand the application of the trend. 

• In the past, wheel bearings for cars were most often used in pairs with single row tapered roller or ball bearings. With the development of technology, cars have been widely used car wheel hub unit.The use of wheel bearing units is growing in scope and volume, and has now developed to the fourth generation, the first generation is composed of double-row angular contact bearings.

• The second generation has a flange on the outer race to hold the bearing in place, allowing the bearing to be simply slipped onto the axle and secured with a nut. This makes maintenance of the car easier.

• The third generation wheel hub bearing unit is a bearing unit mated to the anti-lock brake system ABS. The wheel unit is designed to have an inner flange and an outer flange, the inner flange is bolted to the drive shaft and the outer flange mounts the entire bearing together.

The fourth generation of wheel bearing unit is to make the isokinetic universal joint and the bearing into a whole, solving the shortcomings of the existing technology that the size of the wheel hub increases due to the integrated structure of the wheel hub and the isokinetic universal joint, resulting in the increase of the weight of the wheel hub. The development of the fourth generation of wheel hub bearing units has been successful, and it is believed that they will soon be applied to various types of automobiles on a large scale.