The main function of the wheel bearing
is to load and provide precise guidance for the rotation of the hub. It is both an axial load and a radial load and is a very important component. Conventional automotive wheel bearings are a combination of two sets of tapered roller bearings or ball bearings. Bearing installation, oiling, sealing and adjustment of the clearance are all carried out on the car production line. This structure makes it difficult to assemble in a car production plant, high in cost, and poor in reliability. Moreover, when the car is being repaired at the maintenance point, the bearing needs to be cleaned, oiled and adjusted. The hub bearing unit has been developed on the basis of standard angular contact ball bearings and tapered roller bearings. It combines two sets of bearings. Its assembly performance is good. It omits clearance adjustment, light weight, compact structure and large load capacity. It is a sealed bearing. It can be pre-loaded with grease, omitting external hub seals and free of maintenance. It has been widely used in cars, and there is also a tendency to gradually expand applications in trucks.
During the maintenance process, it is often found that some vehicles have large running noise, and the tires are checked for no abnormal wear, and there is no abnormal noise in turning the wheels on the lift. This phenomenon is often caused by abnormal damage to the wheel bearings. The term "abnormal" refers to bearing damage caused by installation reasons. The front wheel bearings of automobiles are generally double row ball bearings. If the hammer is used for installation when installing the bearing, or when the bearing is installed into the bearing housing by installing the inner ring of the bearing, the bearing race of one side will be damaged. Noise is generated when the vehicle is running, and no significant noise is heard when the wheel is off the ground due to the better side of the raceway. Proper installation is the key to long bearing life.