There are two types of corrosion that affect bearing performance: deep corrosion and fretting corrosion. If the amount of water or corrosion agent reaching the inside of the bearing is sufficient to prevent the lubricant from providing protection to the steel surface, two types of corrosion can occur.

　　When water or corrosive elements contact with the steel surface of the bearing, deep corrosion will be formed. Lifting platform can cause spalling and cracks, if the liquid penetrating into the steel is alkaline solution, it will aggravate spalling and cracks. This creates gray black streaks on the raceway. Pitting corrosion occurred over time, further damaging the bearing.

　　Fretting corrosion occurs when the thin oxide film on the clean steel surface covering the bearing is penetrated. Then the oxidation goes further into the material. The reason for this is the loose fit between the bearing ring and the shaft or bearing seat. Fretting corrosion can produce corrosion areas on the outer surface of the outer ring or in the hole of the inner ring.

　　Fortunately, precautions can be taken to mitigate the effects of corrosion. If design modifications are required to reduce exposure to corrosive elements, performance requirements must be considered. It's also important to identify contaminants - water, salt and acid. According to different environmental pollutants, preventive measures can be taken. For example, if there is a salt spray, electroplated chromium can be used as a barrier.

　　In general, bearings are devices used to achieve rotational or linear motion while reducing friction and handling stress. Like a wheel, bearings actually allow the device to roll, which reduces friction between the bearing surface and its rolling surface. As the friction decreases, it's very easy to move in a rotational or linear manner - which also improves speed and efficiency.

　　In order to meet all these functions, the bearing adopts a relatively simple structure: a ball with a smooth metal surface inside and outside, which helps to roll. The ball itself carries the weight of the load - the force of the load weight is the force that drives the bearing to rotate. However, not all loads exert forces on the bearings in the same way. There are two different loads: radial and thrust.