Motor bearing
Electric motor bearing, also referred to as motor bearing or motor bearing, is a specialized type of bearing designed specifically for use in electric motors or motors. The bearing plays a crucial role in supporting the motor's shaft, guiding its rotation, and withstanding any idle parts on the shaft. The term "bearing" encompasses a wide range of options, but the four most commonly used in motors are rolling bearings, sliding bearings, spherical plain bearings, and oil-impregnated bearings. Rolling bearings, which feature rolling elements, are the most prevalent type of motor bearings. On the other hand, sliding bearings pertain to bearings that lack rolling elements and are intended for sliding motion, with some utilizing Boundary Lubricants.
Working Principle
Most small and medium-sized motors utilize rolling bearings. Large and medium-sized motors also employ rolling bearings. In small motors, ball bearings (specifically deep groove ball bearings) are utilized. On the load side of medium-sized motors, roller bearings are used for high-load conditions, while ball bearings are used on the non-load side (although the opposite arrangement is also possible, such as in 1050kW motors). Rolling bearings are lubricated with grease, but can also be lubricated with lubricating oil.
Installation
The installation of motor bearings directly impacts the accuracy, lifespan, and performance of the bearings. Therefore, it is crucial to thoroughly understand the bearing installation process and adhere to the operational standards, which include the following aspects.
Clean the bearing and its associated parts. If the bearing is lubricated with grease and has oil seals or dust covers on both sides, the seal ring bearing does not need to be cleaned before installation.
● Inspect the size and finish of the associated parts.
● Determine the method of installation.
The installation of the bearing should be based on the structure, size, and compatibility of the bearing components. Apply pressure directly to the end face of the raceway with a tight fit and avoid transmitting pressure through the rolling elements. The following methods are commonly used for bearing installation:
a. Press fit
If the inner ring of the bearing fits tightly with the shaft, and the outer ring fits loosely with the bearing seat hole, the bearing can be pressed onto the shaft first, and then the shaft with the bearing can be installed into the bearing seat hole. Use an assembly sleeve made of soft metal material (such as copper or mild steel) on the end face of the inner ring of the bearing.
hole, the bearing can be pressed into the seat hole by first loosely fitting the inner ring and the shaft. In this case, the assembly sleeve's outer diameter should be slightly smaller than the seat hole's diameter.
Alternatively, a method called heating with thermal expansion can be used to convert a tight fit into a loose fit by heating either the bearing or the housing. This method is commonly used and saves labor during installation, especially for bearings with significant interference. To use this method, place the bearing or the separable bearing's ferrule in an oil tank and heat it evenly at a temperature of 80-100°C. Then, remove it from the oil and promptly install it on the shaft. To ensure a tight fit after cooling, the bearing can be axially tightened.
To ensure proper heating of the bearing using the oil tank, it is necessary to have a mesh grid positioned at a specific distance from the box's bottom. Alternatively, the bearing can be suspended using a hook. Placing the bearing directly on the box's bottom must be avoided in order to prevent the entry of coarse impurities into the bearing and to ensure even heating.
English
