How to clean the motor shaft

The motor should normally be cleaned and refueled after 2000 hours of use. There are two ways to clean the bearing:
First, the hot oil cleaning method Due to the use of a long time, soft dry oil or anti-rust cream hardened bearings, should be immersed in 100-200 ° C hot oil, clamp the bearing with pliers, brush the oil on the bearing clean. The soft dry oil or rust preventive paste is melted when heated to 100-200 ° C and is easily washed out from the gap of the bearing. Sometimes the bearing is shaken several times in the oil. Oil will also flow away from the gap.
When cleaning the centripetal spherical bearing of the old motor or the imported motor, the ball, the bead frame and the inner ring should be laterally turned out from the outer ring and then immersed in the hot oil. The short cylindrical roller bearing should also be rolled when cleaning. The bead frame, the inner ring and the outer ring are disengaged.
When hot oil is cleaned, the temperature of the oil should not exceed 20 °C. If you use an open flame to directly heat, you should take care to prevent the oil from burning. The bearing should be hung in the oil pan, and the bottom will cause overheating and reduce the hardness.
Second, the general cleaning method Put the bearing in kerosene for 5-10 minutes, pinch the inner ring with one hand, turn the outer ring with the other hand, the dry oil or anti-rust cream on the bearing will fall. Then put the bearing into the cleaner kerosene, brush it with a soft brush, wash the oil in the ball and the gap, then put it in the gasoline for 1 time, remove it and put it on clean paper. When cleaning the radial spherical ball bearing and the short cylindrical roller bearing, the ball, the bead frame, the inner ring and the outer ring should be disconnected and cleaned.
The cleaning of the bearing mounted on the shaft is mainly by the method of spraying oil or spraying with a grease gun. The oil that is easy to be cleaned is first used with kerosene and then with gasoline; the oil that is difficult to clean is first washed with hot oil of 100-200 °C. Or oil gun spray, then clean with gasoline. Be careful not to scratch the bearing with a sharp tool: hard grease or rust, so as not to damage the smoothness of the bearing rolling elements and the groove ring. The cleaned bearings are wiped dry with a clean cloth.

For more information and purchase please visit: https://www.supplyforever.com

Matching and preloading of household appliance bearings

Preloading effect
Preloading refers to the use of the bearing in the play by changing the relative position of the inner and outer rings before the bearing is loaded. For household appliances bearings, the main role of pre-tightening is to improve bearing stiffness and suppress vibration noise.
Preload on the bearing noise
When the bearing is subjected to radial load, due to the radial clearance, only part of the steel ball is subjected to load (ABC in the figure), which is called the bearing area, and the other is called the non-bearing area. During the movement of the steel ball from the D to the D' in the non-bearing zone, the magnitude and direction of the combined force of the self-weight and the centrifugal force of the steel ball constantly change, and the steel balls alternately collide with the inner and outer ring raceways, so that abnormal noise is generated inside the bearing. This abnormal sound can be eliminated by preloading the bearing.
However, if the pre-tightening force is too large, the bearing friction increases, the temperature rises, and the noise life of the bearing decreases. Therefore, it is important to choose a suitable preload.
The structure of NSK common dust cover and sealing ring is shown in the figure below. The dust cover (ZZ) is stamped from a steel plate, and the seal ring is made of rubber covered with steel. Among them, the sealing ring is divided into two types: non-contact type (VV) and contact type (DDU, DDW).

For more information and purchase please visit: https://www.supplyforever.com