Precision Bearings: The Effect of Fatigue Pitting on Troubleshooting Precision Bearings

When the rolling element is subjected to load, contact stress will be generated on the contact surface between the rolling element and the inner and outer rings. The inner and outer rings and the rolling element have relative rotational motion during operation, so the contact stress will change. When the contact stress exceeds the specified value, fatigue cracks will occur under the surface and gradually extend to the surface, causing fatigue pitting on the surface of the inner and outer ring rolling elements, resulting in the loss of rotational accuracy, noise, impact and vibration of the precision bearing. Therefore, pitting is a failure form of rolling precision bearings. Now, let's understand the impact of fatigue pitting on precision bearing troubleshooting!

Add the use of precision bearings Period method:

　　The life of precision bearings is closely related to production, manufacturing, installation and application. Therefore, only by doing well in each stage can the precision bearings reach the operating condition and increase the service life of the precision bearings.

　　1. Selection and operation of the dimensional tolerance of the shaft and bearing chamber: After the bearing is pressed into the bearing, it should be able to rotate easily without a slider. When it is obviously inconvenient to rotate, the size of the shaft is too large, please reduce the dimensional tolerance. After the precision bearing is pressed into the shaft, if the rotation is obviously "loose", the dimensional tolerance of the shaft may be large, or the concentricity of the shaft may be poor. Therefore, in the control of dimensional tolerances of precision bearings and precision bearing chambers, good concentricity is required. At this stage, many Chinese manufacturers can only operate dimensional tolerances but not concentricity.

　　2. Installation method: Since precision bearings are high-precision products, improper installation can easily damage the cross-section of the precision bearings, thereby damaging the bearings. The installation of precision bearings requires a special type of shell, which cannot be knocked casually. When pressing the shaft, only force is applied to the circle; when pressing the large circle, only force is applied to the large circle. When installing a standard pneumatic or hydraulic press, when riveting horizontally from left to right, if deflection occurs, the cross section of the bearing will be destroyed by the precision bearing and the wire of the precision bearing will be damaged.

　　3. Avoid dirt: When the bearing is placed on the motor rotor to achieve the dynamic balance of the rotor, the iron pins generated by the dynamic balance of the rotor are easily put into the precision bearing, so keep the rotor in good dynamic balance before installing the bearing. Some manufacturers install oil or vegetable oil in the bearing chamber to moisten the bearing chamber for easy installation, but it is difficult for the actual operator to control the amount of oil or vegetable oil in the precision bearing chamber. If there is a lot of oil or vegetable oil in the chamber, the rotation of the bearing will follow the shaft and adhere to the precision bearing. Do not apply oil or vegetable oil to the precision bearing chamber. When it is necessary to apply, please do not accumulate in the precision bearing chamber during operation.

　　4. Prevention of paint rust: The characteristic of paint rust is that it is often found in closed motors. The sound of the motor is very good when it is installed, but after being placed in the warehouse for a period of time, the sound of the precision bearing motor becomes very loud, and the bearings are severely rusted when they are disassembled. In the past, many manufacturers believed that it was a problem with the precision bearings.

　　The above is an introduction to the impact of fatigue pitting on the troubleshooting of precision bearings. If you need to know more, please feel free to contact us!