1, motor maintenance motor bearings cleaning

　　When removing the bearing for maintenance, first record the bearing appearance and confirm the residual amount of lubricant. After sampling and checking the lubricant, wash the bearing. As a cleaning agent, gasoline and kerosene are commonly used.

　　Remove the bearing cleaning, coarse cleaning and fine washing, respectively in the container, first put the metal mesh bottom, so that the bearing does not directly contact with the container dirt. Care should be taken that the rolling surface of the bearing will be damaged if the bearing rotates with dirt during rough cleaning. In the coarse cleaning oil, use a brush to remove grease, adhere to the material, roughly clean, into fine washing.

　　Fine cleaning, is the bearing in the cleaning oil while rotating, while carefully cleaning. Also, always clean the oil. The motor should be cleaned and oiled after 2000 hours of use. There are two cleaning methods for bearings:

　　1) hot oil cleaning method due to the use of the old, soft dry oil or rust paste hardened bearing, should be immersed in 100 -- 200℃ hot oil, with pliers clamp bearing, brush the bearing with a brush to clean the grease. The soft-dry oil or antirust cream melts when heated to 100 -- 200℃ and is easily washed out of the gaps in the bearing. Sometimes the bearing is simply shaken many times in the oil. Oil also flows through crevices.

　　When cleaning the radial spherical bearings of old motors or imported motors, the ball, bead bracket and inner ring should be transversely turned out from the outer ring and then immersed in hot oil. The roller, bead bracket, inner ring and outer ring should also be disengaged during cleaning of short cylindrical roller bearings.

　　When cleaning hot oil, the oil temperature should not exceed 20℃.

　　2) in general cleaning method, soak the bearing in kerosene for 5-10 minutes, hold the inner ring with one hand, and turn the outer ring with the other hand, the dry oil or rust cream on the bearing will fall off. Then put the bearing into the cleaner kerosene, with a fine soft brush brush wash, the ball and gap in the oil wash, and then put in the gasoline to clean 1 time, after taking out on clean paper. When cleaning radial spherical ball bearing and short cylindrical roller bearing, remove the ball, ball frame, inner ring and outer ring.

　　The bearing mounted on the shaft is cleaned mainly by oil spraying or grease-gun spraying. Oil stains that are easy to clean are first cleaned by kerosene and then by gasoline. Difficult to clean off the oil, first with 100-200℃ hot oil leaching or injection gun, and then clean with gasoline. Be careful not to scrape the bearing with a sharp tool: hard grease or rust, so as not to damage the bearing rolling body and groove ring parts of the clean, clean bearing with a clean cloth dry.

　　2. Bearing maintenance and judgment

　　In order to determine whether the removed bearing can be used again, check carefully the state of raceway surface, rolling surface and mating surface, the wear condition of retainer, the increase of bearing clearance and whether there is any damage or abnormality related to the decrease of dimensional accuracy after the bearing is cleaned. For non-separating ball bearings, support the inner ring horizontally with one hand and rotate the outer ring to ensure smoothness.

　　Tapered roller bearings and other separate bearings can be used to check the raceway surface of the rolling body and outer ring respectively.

　　Large bearings can not be rotated by hand. Please check the appearance of rolling body, raceway, cage and retaining surface. The more important the bearing is, the more careful the inspection is.

　　The determination of whether the bearing is reusable is based on the degree of damage, mechanical properties, importance, operating conditions, and the next maintenance period. However, they can no longer be used and must be replaced if:

　　(a) cracks or gaps in any one of the inner ring, outer ring, rolling body or cage;

　　(b) any one of the rings and rolling bodies is broken;

　　(c) significant sticking injuries on raceway surface, fender and rolling body;

　　(d) significant wear on the retainer or significant relaxation of rivets;

　　(e) rust and damage on raceway surface and rolling body;

　　(f) severe indentation and punching marks on raceway surface and rolling body;

　　(g) obvious creep on inner diameter surface or outer diameter surface of inner ring;

　　(h) apparent discoloration due to heat;

　　(I) the bearing sealed with grease, the sealing ring or dust cover are obviously damaged.