Lubrication requirements of motors for motor bearings
(1) According to the temperature of the operating environment where the motor operates and its own temperature, the general environment of ordinary low-voltage motors uses #3 lithium-based grease. If the ambient temperature of the motor is high or the temperature of the motor bearing is high, use high temperature resistant Mobil grease.
(2) According to the number of pole pairs (or the operating speed of the motor) of the motor (mainly a high-voltage motor). 7008 aviation lubricating oil is generally used for high speed, and molybdenum disulfide is generally used for low speed.
(3) Determined according to the size of the bearing shaft clearance of the motor (mainly a high-voltage motor). Generally, motors with large bearing clearances use coarse lubricating oils such as molybdenum disulfide, and motors with small bearing clearances use fine lubricating oils such as 7008.
There are many types and specifications of electric motors, and the selection of lubricant for general electric motors depends on the type of motor bearings, number of revolutions, temperature, load, etc. Small motors and medium-sized motors use rolling bearings (with an inner diameter of 25mm or more), and sealed maintenance-free bearings can be used directly. Generally, the bearings need to be lubricated with grease, and the grease is usually filled at one time (about 1/2 grease is filled in the bearing, and it will be cleaned and replaced after one year of use). Rolling bearings or sliding bearings may be used in large motors, and both lubricants may be used. Generally, sliding bearings are lubricated with oil, and rolling bearings are lubricated with grease. The bearing temperature of the motor should generally be controlled between 65-80°C, and the alloy sliding bearing is preferably lower than 65°C.