The quality of bearing installation will affect the accuracy, lifespan, and performance of the bearing. Therefore, please fully study the installation of bearings, that is, please follow the operating standards including the following items for bearing installation.

1、 Clean bearings and related parts

For bearings that have been lubricated with grease and have oil seals or dust covers on both sides, there is no need to clean the sealing ring bearings before installation.

2、 Check the dimensions and precision machining of relevant parts

3、 Installation method

The installation of bearings should be determined based on the bearing structure, size, and mating properties of the bearing components. Pressure should be directly applied to the end face of the tightly fitted ring, and pressure should not be transmitted through rolling elements. The following methods are generally used for bearing installation:

a. Press fit

When the inner ring of the bearing is in a tight fit with the shaft, and the outer ring is in a loose fit with the bearing seat hole, a press can be used to first press the bearing onto the shaft, and then install the shaft and bearing together into the bearing seat hole. When pressing, a soft metal material assembly sleeve (copper or soft steel) is placed on the end face of the bearing inner ring. The inner diameter of the assembly sleeve should be slightly larger than the diameter of the shaft neck, and the outer diameter should be slightly smaller than the edge of the bearing inner ring to avoid being pressed onto the cage. The outer ring of the bearing fits tightly with the bearing seat hole, while the inner ring fits loosely with the shaft. The bearing can be pressed into the bearing seat hole first, and the outer diameter of the assembly sleeve should be slightly smaller than the diameter of the seat hole. If the bearing ring is tightly matched with the shaft and seat hole, the installation of the inner and outer rings should simultaneously press into the shaft and seat hole, and the structure of the assembly sleeve should be able to simultaneously press the end faces of the bearing inner and outer rings.

b. Heating coordination

The installation method of transforming a tight fit into a loose fit by heating the bearing or bearing seat and utilizing thermal expansion. It is a commonly used and labor-saving installation method. This method is suitable for the installation of bearings with large interference. Before hot installation, place the bearing or separable bearing ring into the oil tank and heat it evenly at 80-100 ℃. Then, remove it from the oil and install it on the shaft as soon as possible. To prevent the inner ring end face and shaft shoulder from not tightly fitting after cooling, the bearing can be tightened axially after cooling. When the outer ring of the bearing is tightly matched with a light metal bearing seat, the hot installation method of heating the bearing seat can avoid scratches on the mating surface. When heating bearings with oil tanks, there should be a grid at a certain distance from the bottom of the box, or a hook should be used to hang the bearing. The bearing should not be placed on the bottom of the box 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 to not exceed 100 ℃ to prevent tempering effect and reduce the hardness of the ring.

c. Installation of tapered hole bearings

Tapered hole bearings can be directly installed on a tapered journal or on the conical surface of a fixed sleeve and a detachable sleeve. The degree of tightness of their fit can be measured by the reduction of the radial clearance of the bearing. Therefore, the radial clearance of the bearing should be measured before installation, and the clearance should be frequently measured during installation to achieve the required reduction. During installation, locking nuts are generally used for installation, and heating installation can also be used.

d. Installation of thrust bearings

The overall fit of the thrust bearing with the shaft is generally a transitional 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 central spring of the bidirectional thrust bearing should be fixed on the shaft to prevent rotation relative to the shaft. The installation method of bearings usually involves shaft rotation, so the fit between the inner ring and the shaft is a win fit, while the fit between the outer ring and the bearing chamber is a clearance fit.