When disassembling bearings for maintenance, first record the appearance of the bearings, confirm the remaining amount of lubricant, take samples of the lubricant for inspection, and then clean the bearings. As a cleaning agent, gasoline and kerosene are generally used.
The cleaning of dismantled bearings can be divided into coarse cleaning and fine cleaning. They are respectively placed in containers, with metal mesh pads placed at the bottom to prevent the bearings from directly contacting the dirt in the container. During rough cleaning, if the bearing rotates with dirt, it can damage the rolling surface of the bearing and should be taken care of. In the coarse cleaning oil, use a brush to remove lubricating grease and adhesive substances. After roughly cleaning, proceed to fine cleaning.
Fine cleaning refers to carefully cleaning the bearings while rotating them in cleaning oil. In addition, cleaning oil should also be kept clean regularly. Motors should generally be cleaned and oiled after 2000 hours of use. There are two cleaning methods for bearings:
1) Hot oil cleaning method: Due to prolonged use, bearings that have hardened with soft dry oil or rust preventive paste should be immersed in hot engine oil at 100-200 ℃, clamped with pliers, and cleaned of oil stains on the bearings with a brush. Soft dry oil or anti rust paste can melt when heated to 100-200 ℃, making it easy to wash out from the gaps in the bearings. Sometimes just shake the bearing multiple times in the oil. Oil stains can also flow away from cracks.
When cleaning centripetal spherical bearings of old or imported motors, the balls, ball racks, and inner rings should be horizontally rotated out of the outer ring and then immersed in hot oil. When cleaning short cylindrical roller bearings, the rollers, ball racks, inner rings, and outer rings should also be separated.
During hot oil cleaning, the temperature of the oil should not exceed 20 ℃.
2) General cleaning method: Soak the bearing in kerosene for 5-10 minutes, hold the inner ring with one hand, and rotate the outer ring with the other hand. The dry oil or rust preventive paste on the bearing will fall off. Then place the bearing in clean kerosene, brush it with a soft bristle brush, clean the oil stains in the ball and gap, and then wash it once in gasoline. After removing it, place it on clean paper. When cleaning centripetal spherical ball bearings and short cylindrical roller bearings, the balls, ball racks, inner rings, and outer rings should be separated for cleaning.
The cleaning of bearings installed on the shaft mainly relies on spraying oil or spraying with an oil gun. The easily cleaned oil stains are first cleaned with kerosene and then with gasoline; For oil stains that are difficult to clean, first wash them with 100-200 ℃ hot engine oil or spray them with an oil gun, and then clean them with gasoline. Be sure not to use sharp tools to scrape the bearings: hard oil stains or rust, to avoid damaging the smoothness of the rolling element and groove ring parts of the bearings. Wipe the cleaned bearings dry with a clean cloth.