Requirements for the operation of motor bearings

Whether the motor bearing is installed or not will directly affect the accuracy, life and performance of the bearing. Therefore, please fully study the bearing installation, that is, please install the motor bearing according to the operating standards including the following items.

1. Cleaning motor bearings and related parts

2. Check the dimensions and finishing of related parts

3. Installation method

The installation of the motor bearing should be determined according to the bearing structure, size and the matching nature of the motor bearing components. The pressure should be directly applied to the end face of the ferrule that is tightly fitted, and the pressure should not be transmitted through the rolling elements. The installation of the motor bearing generally adopts the following methods:

a. Press fit

When the inner ring of the motor bearing is tightly fitted with the shaft, and the outer ring is loosely fitted with the bearing seat hole, the bearing can be press-fitted on the shaft first, and then the shaft together with the bearing is installed into the bearing seat hole. On the end face of the inner ring of the bearing, pad a fitting sleeve (copper or mild steel) made of soft metal material.

The outer ring of the motor bearing is tightly fitted with the bearing seat hole. When the inner ring and the shaft are loosely fitted, the bearing can be pressed into the bearing seat hole first. At this time, the outer diameter of the assembly sleeve should be slightly smaller than the diameter of the seat hole.

If the bearing ring of the motor is tightly fitted with the shaft and the seat hole, the inner ring and the outer ring should be pressed into the shaft and the seat hole at the same time.

b. Heating fit

A mounting method that uses thermal expansion to convert a tight fit into a loose fit by heating the bearing or housing. It is a common and labor-saving installation method. This method is suitable for the installation of bearings with large interference

Put the motor bearing or the ferrule of the separable bearing into the oil tank and heat it evenly at 80-100℃ before hot-loading, then take it out of the oil and install it on the shaft as soon as possible. , the motor bearing can be axially tightened after cooling.

When the outer ring of the motor bearing is tightly fitted with the bearing seat made of light metal, the hot-fitting method of heating the bearing seat can be used to prevent the mating surface from being scratched.

When heating the bearing with the oil tank, there should be a mesh grid at a certain distance from the bottom of the box, or use a hook to hang the bearing. The motor bearing cannot be placed on the bottom of the box to prevent heavy impurities from entering the motor bearing or uneven heating. Thermometer, strictly control the oil temperature not to exceed 100 ℃ to prevent the tempering effect and reduce the hardness of the ferrule.