Bearing installation

The quality of bearing installation will affect the precision, life and performance of the bearing. Therefore, please fully study the installation of the bearing, that is, please install the bearing according to the operating standards including the following items.
●, clean the bearing and related parts (for greased bearings and oil seals or dust covers on both sides, the seal ring bearing does not need to be cleaned before installation.)
●, check the size and finishing of related parts
●, installation method
The installation of the bearing should be based on the bearing structure, size and matching properties of the bearing components. The pressure should be directly applied to the end face of the tight-fitting ring, and the pressure should not be transmitted through the rolling element. The following methods are generally used for bearing installation:
a. Press-fit
When the inner ring of the bearing is tightly fitted with the shaft and the outer ring is loosely fitted with the bearing seat hole, the bearing can be pressed onto the shaft with a press, and then the shaft and the bearing are installed into the bearing seat hole together. When pressing, a soft metal assembly sleeve (copper or soft steel) is placed on the end face of the inner ring of the bearing.
When the outer ring of the bearing is tightly matched with the bearing seat hole and the inner ring is loosely matched with the shaft, the bearing can be pressed into the bearing seat hole. At this time, the outer diameter of the sleeve should be slightly smaller than the diameter of the seat hole.
If the bearing ring is tightly matched with the shaft and the seat hole, the inner and outer rings should be pressed into the shaft and the seat hole at the same time when installing the indoor ring. The structure of the sleeve should be able to press the end faces of the inner and outer rings of the bearing at the same time.
b. Heating fit
By heating the bearing or bearing seat, the installation method of converting the tight fit into a loose fit by using thermal expansion. It is a common and labor-saving installation method. This method is suitable for the installation of bearings with large interference. Before hot installation, put the bearing or the ring of the separable bearing into the oil tank and heat it evenly to 80-100℃, then take it out of the oil and install it on the shaft as soon as possible. To prevent the inner ring end face and the shaft shoulder from not fitting tightly after cooling, the bearing can be axially tightened after cooling. When the outer ring of the bearing is tightly matched with the light metal bearing seat, the hot installation method of heating the bearing seat can avoid scratches on the matching surface.
When heating the bearing with an oil tank, there should be a mesh grid at a certain distance from the bottom of the tank, as shown in Figure 2-7, or the bearing should be hung with a hook. The bearing cannot be placed on the bottom of the tank to prevent impurities from entering the bearing or uneven heating. There must be a thermometer in the oil tank, and the oil temperature must be strictly controlled not to exceed 100°C to prevent the tempering effect and reduce the hardness of the ferrule.
c. Installation of thrust bearings
The fit between the thrust bearing and the shaft is generally a transition fit, and the fit between the seat ring and the bearing seat hole is generally a clearance fit. Therefore, this type of bearing is easier to install. The center shaft of the bidirectional thrust bearing should be fixed on the shaft to prevent rotation relative to the shaft.
The installation method of the bearing is generally that the shaft rotates, so the fit between the inner ring and the shaft is an over-win fit, and the fit between the outer ring of the bearing and the bearing chamber is a clearance fit.
●, Bearing operation inspection
After the bearing is installed, an operation inspection should be carried out immediately to determine whether the installation is normal.