Electric motor bearing selection and application

Bearing configuration should pay attention to the problem

To design an ideal bearing configuration, the following needs to be done, of course, the motor bearing configuration is no exception.


● Choose the right bearing type.

● Determine the appropriate bearing size.

● The structure and design of other components in the configuration.

● Appropriate tolerance fit and bearing clearance or preload.

● How to fix the bearing.

● Suitable sealing system.

● The type and amount of lubricant.

● Installation and disassembly methods.

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Each of these factors affects the performance, reliability, and cost-effectiveness of the entire bearing configuration. The time and effort involved in selecting a bearing depends on whether the user has experience with a similar bearing configuration. If these experiences are not available, there are special requirements on the application, or the cost of the bearing configuration and other related factors need to be considered in detail, more detailed work must be done during the selection process, including more precise calculations or tests. Wait.

Selection of bearing system methods and bearing reliability

The stresses considered in the bearing rating life equation include the stress caused by the external force, the kinematically induced stress from the surface condition, the lubrication condition, and the rolling contact surface. By comprehensively considering the effect of these stresses on bearing life, more accurate predictions of bearing performance and performance can be made in specific applications.

In general, metal fatigue on rolling contact surfaces is the main cause of rolling bearing damage. Therefore for a particular application, based on raceway fatigue is sufficient to select the appropriate rolling bearing and its size. The international standard IS0281 is based on the metal fatigue of rolling contact surfaces. But more importantly, the complete bearing should be considered as a system where the possible existence of components, ie cages, lubricants and seals, whose life expectancy plays an equal role in bearing durability, and in some cases also Plays a leading role. In theory, it is the ideal working life when all components reach the same life.

In other words, the actual working life of the bearing must reach the calculated life, and the working life of the component must also at least reach the calculated life of the bearing. Key components include cages, seals, and lubricants. In practical applications, metal fatigue is the most important factor.