Motor bearing, also known as motor bearing or motor bearing, is a kind of special bearing specially applied to motor or motor.The bearing used by the motor is a part that supports the shaft. It can guide the rotation of the shaft and can also withstand the idling parts on the shaft.There are four types of bearings commonly used in motors, namely rolling bearings, sliding bearings, joint bearings and oil-impregnated bearings.Common motor bearings are rolling bearings, that is, bearings with rolling elements.

　　working principle

　　Motor bearings use smooth metal balls or rollers and lubricated inner and outer ring metal surfaces to reduce friction.These balls or rollers "carry" the load and support the motor shaft, so that the motor (rotor) can rotate smoothly.

　　Bearing type

　　Most small and medium-sized motors use rolling bearings.

　　Large and medium-sized motors also use rolling bearings.

　　Ball bearings (such as deep groove ball bearings) are used for the bearings at both ends of the small motor.

　　Medium-sized motors use roller bearings on the load side (such as cylindrical roller bearings, tapered roller bearings. Generally used for high load conditions), and ball bearings on the non-load side (but there are also the opposite situations, such as 1050kW motors).The rolling bearings are lubricated with grease, but they are also lubricated with lubricating oil.

　　Bearing installation

　　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 in accordance with the operating standards including the following items:

　　Clean motor bearings and related parts. For bearings that have been grease lubricated and have oil seals or dust caps 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 motor bearing should be based on the bearing structure, size and the matching nature of the bearing components. The pressure should be directly applied to the end face of the tightly fitted ring, and no pressure can be transmitted through the rolling elements. The installation of the motor bearing generally adopts the following methods:

　　1. Press fit

　　When the inner ring of the motor bearing and the shaft are tightly fitted, and the outer ring and the bearing housing hole are loosely matched, the motor bearing can be press-fitted on the shaft with a press, and then the shaft and the bearing are installed in the bearing housing hole and press-fitted When the end face of the inner ring of the motor bearing is filled with an assembly sleeve made of soft metal material (copper or mild steel).

　　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 motor 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 motor bearing ring is tightly fitted with the shaft and the housing hole, the inner ring and the outer ring should be pressed into the shaft and the housing hole at the same time during installation, and the structure of the assembly sleeve should be able to tighten the end faces of the inner ring and the outer ring at the same time .

　　2. Heating coordination

　　By heating the motor bearing or bearing seat, thermal expansion is used to transform the tight fit into a loose fit installation method.It is a common and labor-saving installation method.

　　This method is suitable for the installation of motor bearings with large interference. Before hot assembling, put the motor bearings or separable bearing rings into the oil tank and heat them evenly at 80-100℃, and then take them out of the oil and install them on the shaft as soon as possible. , In order to prevent the inner ring end face and the shaft shoulder from not fitting tightly after cooling, the motor bearing can be axially tightened after cooling.When the outer ring of the motor bearing is tightly fitted with the light metal bearing seat, the hot-fitting method of heating the bearing seat can be used to avoid scratches on the mating surface.

　　When heating the motor bearing with an oil tank, there should be a grid at a certain distance from the bottom of the box, or the motor bearing should be hung with a hook. The motor bearing cannot be placed on the bottom of the box to prevent sinking impurities from entering the motor bearing or uneven heating in the oil tank. There must be a thermometer, and strictly the oil temperature should not exceed 100°C to prevent the tempering effect and reduce the hardness of the ferrule.