What Are Hub Bearings?

Hub bearing is the main role of bearing and provide accurate guidance for the rotation of the hub, it bears both axial load and radial load, is a very important part.  The traditional 

automobile wheel bearings are composed of two sets of tapered roller bearings or ball bearings. The installation, oiling, sealing and clearance adjustment of bearings are all 

carried out on the automobile production line. 

This structure makes it difficult to assemble in automobile production plants, high cost, poor reliability, and the car in the maintenance point maintenance, but also need to 

clean, oiling and adjustment bearings.  Wheel hub bearing unit is in the standard angular contact ball bearings and tapered roller bearings, on the basis of it will be two sets 

of bearing as a whole, has the assembly clearance adjustment performance is good, can be omitted, light weight, compact structure, 

large load capacity, for the sealed bearing prior to loading, ellipsis external wheel grease seal and from maintenance etc, and has been widely used in cars,  In the heavy truck 

also has the trend of gradually expanding the application.

The difference between hub and bearing

1. Different properties: the wheel hub is the rotating part of the wheel core connected by the column of the tire inner profile wheel steel, that is, the metal part installed on the 

shaft of the center of the tire. Bearing is an important part of modern mechanical equipment.

2. Different characteristics: To compare the bearing capacity against pitting corrosion of bearings, the maximum load that can be borne is the basic rated dynamic load, 

expressed by C, when the rated life of bearings is one million revolutions (106). Hub According to the characteristics and needs of different models, hub surface treatment 

process will take different ways.

3. Different functions: the main function of bearings is to support the mechanical rotating body, reduce the friction coefficient in the process of movement, and ensure the 

rotary accuracy. The third generation hub bearing unit is used in conjunction with the bearing unit and anti-lock brake system. The hub unit is designed with an inner flange 

bolted to the drive shaft and an outer flange that holds the entire bearing together.

What happens when automobile hub bearing is damaged  

When one of the four hub bearings of the vehicle is damaged, you will hear a continuous buzzing sound in the car when the car is moving. This sound is not clear where it 

comes from. It feels like the whole car is full of this buzzing sound, and the faster the speed, the greater the sound.  Here's how to judge:

Method one: open the window to listen to whether the sound comes from outside the car;  

Method two: after improving the speed (when the buzz is larger) will gear in neutral to let the vehicle taxi, observe whether the noise comes from the engine, if there is no 

change in neutral taxi hum that is mostly the wheel bearing problem;

Method 3: temporary parking, check the temperature of the shaft is normal, the method is: use hands to touch the four wheels, the temperature of the general feeling about 

them are consistent (brake shoe, normal clearance, the temperature of the front and rear wheels is a gap, the front wheel is high), if feel difference may continue to slow traffic 

to the pit;

Method 4: lift the car rises (prior to loosen the hand brake, idling), there is no elevator can jack rises one wheel, human fast four wheels, respectively, when there are problems 

of axle, it make a sound, like nothing else axle, using this method can easily distinguish which axle is have a problem.

If the hub bearing is seriously damaged, it has cracks, pitting or ablation, and must be replaced.  Grease is applied before installing the new bearing, and then it is installed in 

the opposite order. The replaced bearing must be flexible and free from clutter and vibration.