Under what circumstances does the motor need to choose a cylindrical roller bearing?


The bearing is a very key component of the motor. It is a pivotal component that connects the stator and rotor of the motor to realize the conversion of electrical energy and mechanical energy. The ball bearing and cylindrical roller bearing are the most commonly used bearing types for small and medium-sized motors. The use of ball bearings, while low-voltage high-power and high-voltage motors, more cylindrical roller bearings.


From the contact analysis between the rolling element and the bearing ring, the ball of the ball bearing is in point contact with the ferrule. When the bearing is running, the contact points are connected into a line, while the roller bearing, the roller and the ferrule are in line contact, and the bearing is running. The lines of contact will be connected into one side. In view of the contact relationship between the rolling element and the ferrule, we can intuitively judge that the ball bearing should be relatively stable during operation, that is, the noise during operation should be smaller; relatively speaking, the cylindrical roller bearing should be relatively loud during operation, but The carrying capacity is higher than the ball bearing.

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For a motor, in more cases, it is necessary to comprehensively use the process. For noise, load and other factors, choose the appropriate bearing to match it. If you want both fish and bear's paw, you may have to do it if necessary. A rational choice.


Common cylindrical roller bearing introduction


Single row cylindrical roller bearings are separable bearings. They are the most common types of bearings for small and medium-sized motors. These bearings are easy to install and disassemble. Both ferrules can be tightly fitted, and the contact line between the rollers and the raceway is corrected. Stress concentration can be reduced.

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The type of cylindrical roller bearing is divided according to the form of its rib. The NU bearing outer ring has two ribs and the inner ring has no ribs. The inner ring of the N-type bearing has two ribs and the outer ring has no ribs. NU and N cylindrical roller bearings are used for the floating end. They are separable bearings for easy installation and removal, and the inner jacket ring can be tightly fitted.

The NJ cylindrical roller bearing has two ribs on the outer ring and a single rib on the inner ring to withstand axial force in one direction.

NUP cylindrical roller bearings are used for the fixed end and can withstand axial forces in both directions. This type of bearing outer ring has two ribs, the inner ring has a fixed rib and a movable rib. An NJ cylindrical roller bearing and a corner ring HJ form a fixed end bearing similar to the NUP type.


Steel and copper cage bearing performance comparison

The cage material is required to have the strength to withstand the vibration and impact loads during operation, and the friction with the ferrule and the rolling element is small, the weight is light, and it can adapt to the bearing operating temperature. Copper cages and steel cages have their own advantages and have their own inadequacies.

● The steel cage is stronger than the copper cage.

●Small and medium-sized bearings are generally cold-rolled and hot-rolled steel plates, and brass plates and stainless steel plates are also used depending on the application. Large-sized bearings are generally made of car cages. The materials are mostly made of structural carbon steel and high-strength brass castings, and also made of ductile iron, aluminum alloy and other materials.

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● The anti-friction effect and wear resistance of copper are very good.

●The steel retainer is not as wear-resistant as copper, and it is easy to peel off when it rubs against the rolling element, and it is the same as the magnetic conductive material. It is difficult to eliminate the residual magnetism after the bearing itself is used. The iron scrap after wear is not easy to discharge due to residual magnetism. Will increase bearing wear.



Reprinted from the network