There are many types and sizes of electric motors. The lubricant selection of general electric motors depends on the bearing type, speed, temperature, load, etc.

Large electric motors often use sliding bearings. There is an oil storage tank or oil pool in the bearing maintenance mesh seat. The oil ring and oil chain are used to lubricate the lubricating oil in the sleeve. There are also oil ropes for lubrication. The service life of the lubricating oil is maintained at 20000-4000 hours.

Small electric motors mostly use rolling bearings, which are lubricated with grease. Usually, the grease is filled once (about 1/2 grease is filled in the bearing, and it is cleaned and replaced after 1 year of use).

Rolling bearings or sliding bearings may be used in medium-sized motors. 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, alloy sliding bearings should not exceed 65°C, and rolling bearings should not exceed 95°C.

The bearing types of the motor are divided into: rolling bearings and sliding bearings.

The selection range of rolling bearings is 63~710 center height; for motors with a center height of more than 710mm, sliding bearings should be selected due to the heavy weight of the rotor. Due to the limitation of the volume of sliding bearings, sliding bearings should not be selected for motors with a center height of less than 450. Rolling bearings are standard parts with the advantages of easy use and maintenance, interchangeability, multiple supply channels, and low prices for small specifications.

However, large-size bearings are subject to restrictions such as the maximum speed and small usage, and the price is relatively high.

Sliding bearings have the advantages of long service life and can achieve larger shaft diameters and speeds.

Small-size sliding bearings are more expensive than rolling bearings.

The lubrication methods of sliding bearings are divided into self-lubrication and forced lubrication. According to the general selection principle, self-lubrication should not be used if forced lubrication can be used. If the main engine has a shared oil station, it is better to use forced lubrication, but there is a possibility of complicated oil pipe layout and oil leakage.

Generally, for 2-pole motors, self-lubrication is used for motors below 1000kW; forced lubrication and lubricating oil are used for motors above 1000KW. The lubricating oil is L-TSA32# turbine oil.

For motors with 4 poles or more, self-lubrication is used for motors below 2000KW, and forced lubrication is used for motors above 2000KW. The lubricating oil is L-TSA46# turbine oil.