The fit of the bearing refers to the combined relationship between the bearing, the shaft, and the bearing seat, that is, how the bearing, the shaft, and the bearing seat are assembled together. This fit can be a tight fit or a loose fit, depending on the type of bearing and the needs of the actual application.
The selection of bearing fit is very important to ensure the normal operation of the bearing, improve the mechanical performance and extend the service life. When selecting a bearing fit, many factors need to be considered, such as load, speed, working environment temperature, lubrication conditions, etc. These factors will affect the accuracy, stiffness and friction of the bearing.
There are three main types of bearing fits, namely interference fit, transition fit and clearance fit.
1. Interference fit: Also known as "negative distance contact", it means that the outer size of the internal object is greater than the inner size of the external object, and the two are tightly meshed together. This kind of matching is suitable for bearings with high speed, high precision and high stability requirements, such as those that bear larger loads or require higher stiffness.
2. Transition fit: It is between interference fit and clearance fit. Sometimes it may be "interference", and sometimes there will be a gap. This matching method is suitable for some bearings that require a certain degree of stability and allow a certain relative movement.
3. Clearance fit: The outer size of the inner object is smaller than the inner size of the outer object, and there is a certain gap between the two. This kind of fit is suitable for bearings that require a certain degree of stability but also allow a certain relative movement, such as low speed, low precision, and situations where slight relative movement is acceptable.
In order to ensure the normal operation of the bearing and extend its service life, factors such as load, rotation speed, working environment temperature and lubrication conditions also need to be considered.
