How to choose the right bearing clearance?

In industrial production and machining, the clearance selection of radial bearings is a very critical problem. Many friends do not know whether to choose CN or C3 when choosing bearing clearance. Today, we're going to talk about this topic to help you clear your mind and make the right choice.

Simply put, the clearance refers to the gap between the inner ring and the outer ring of the bearing. In practical applications, the clearance will affect the performance and life of the bearing. There are several types of clearance, the most common being normal clearance (CN) and extended clearance (C3).

Each clearance has its own specific application scenario:

Normal clearance (CN) : Bearings suitable for ordinary operating conditions, stable temperature and load.

Increased clearance (C3) : suitable for high temperature or high load working environment, because in this condition, the bearing will be due to thermal expansion and other factors lead to smaller clearance. How to choose the right clearance?

1. Understand your application scenario: First of all, clarify the specific environment of bearing work. CN is good enough for normal environments, but if you work at high temperatures, high speeds, or heavy loads, C3 is your choice.

2. Consider the working temperature of the bearing: in a high temperature environment, the shaft and aperture will expand, and a larger clearance is needed to avoid sticking. If the bearing works at high temperatures for a long time, C3 may be more appropriate.

3. Load condition: If the bearing is subjected to heavy load, the choice of C3 with increased clearance can better adapt to this complex condition and avoid early bearing failure.

4. Installation accuracy requirements: In some precision machinery, very high installation accuracy is required, and CN may be more appropriate at this time, because too large clearance may affect the accuracy.

Summary of experience:

Normal environment: Select CN clearance.

High temperature, high speed, heavy load environment: Choose C3 clearance.

Precision requirements: Choose according to specific needs, usually CN is more suitable.