Because all kinds of rolling mechanical parts are inseparable from bearings, maintenance of bearings and filling of lubricating oil are also relatively common things, but in life, cars are rarely used for bearing maintenance. In fact, car wheels The reason why bearings are maintenance-free is due to design.

If the bearing has enough airtightness to keep foreign objects out, the advantage of long-lasting lubricating oil can be exerted. As long as there is lubricating oil, the bearing will not be damaged. Therefore, the car bearing has been designed at the beginning of the design. Taking into account the maintenance problems in the future, maintenance-free bearings are directly used.

This maintenance-free bearing is a fully enclosed bearing that cannot be opened with grease added. This type of bearing is generally only used in trolleys and is called "double row ball bearing", which is sealed for life and can only be replaced when damaged. The service life of this kind of bearing is 150,000 kilometers. Because this kind of bearing also has grease inside, once the grease is exhausted, abnormal wheel noise, bumps, and looseness will occur.

Wheel Hub Bearing

In fact, any bearing needs "butter", because the bearing will have high heat at high speed, if the heat reaches a certain value, the bearing will be damaged. The only way to reduce heat is to have enough lubricating oil. The better the degree of lubrication, the better the smoothness of the movement of the bearing, the smaller the friction and the lower the heat.

Therefore, whether the bearing is durable or not depends entirely on the degree of lubrication. In daily vehicle failures, 9 out of 10 bearings are damaged due to lack of lubrication, while the maintenance cycle of truck wheel hub bearings is about 30,000 kilometers.