Motor bearings are always the subject of discussion in motor products. Different motor products need to match the corresponding bearings. If the bearings are not properly selected, noise, vibration, etc. may directly affect the performance of the motor. In severe cases, the motor The service life has an impact.

Deep groove ball bearings are one of the most widely used bearing types. Motors with special operating conditions have different requirements for bearings. If necessary, specific requirements should be made for bearing materials and manufacturing processes.

Deep groove ball bearing noise can be transmitted through structural conduction or air media. The deep groove ball bearing in rotation is itself the source of sound source or vibration, causing bearing vibration or noise to occur, mainly from the natural vibration of the bearing and the vibration generated by the relative motion inside the bearing.

In actual use, the choice of bearing grease, the amount of filling, the installation of the bearing and the subsequent maintenance and use have a direct impact on the bearing operation. Therefore, in the design phase, manufacturing phase and customer's use and maintenance phase of the motor, the bearings should be maintained with necessary and standardized maintenance to avoid motor quality problems caused by the bearings.

1. Selection of special specifications for motor bearings

●Special materials: stainless steel bearings are recommended for use when anti-rust performance is required, or when working in a corrosive environment such as salt water;

●High temperature tempering treatment: the temperature is relatively high, exceeding 150 degrees, the high temperature tempering heat treatment method is required for the bearing ring. The tempering temperature of the normal heat treatment is 160 hours for 3 hours, then the high temperature tempering is based on actual conditions. The situation is 180 degrees or 220 degrees, or 250 degrees.

● Freezing treatment: After quenching, before tempering, a process of freezing at a low temperature of 70 degrees is added. The main purpose is to reduce the content of retained austenite inside the ferrule and improve the stability of bearing dimensional accuracy.

2. Selection of sealing structure and material of motor bearing

The purpose of the bearing seal is to prevent the leakage of the lubricant in the bearing part, and to prevent external harmful objects such as dust, moisture and foreign matter from intruding into the bearing, so that the bearing can operate safely and permanently under the required conditions. In the following cases, it is a priority to select a sealed bearing that is pre-filled with grease.

● Bearings are not required to operate permanently.

● Under low and medium speed, load and temperature operating conditions.

● Requires low production costs.

● Adding a lubricant to a difficult part, or adding a lubricant in the future.

The use of such bearings, the bearing shell (box) and its sealing design can be simplified, greatly reducing the manufacturing cost: when the conditions of use are not critical, even for a long time, it is widely used in the home appliances, vehicles, motors and other industries .

● reduce friction and wear;

●The conduction of frictional heat and the removal of heat generated by the friction of the bearing require the heat to be conducted to or away by the intermediary of the lubricant, so that the bearing temperature is lowered and the lubricant and the bearing are maintained for a long time.

● Alleviate the concentration of local stress.

4. Motor bearing installation and use

Rolling bearings are precision components that should be installed and used as standard. When the bearing is installed, the bearing ring should be stressed. That is, when the bearing is pressed onto the shaft, the inner ring of the bearing should be stressed, otherwise the outer ring of the bearing is stressed; while the assembly of the shaft and the bearing chamber is satisfied, the bearing must be guaranteed. The inner and outer rings are stressed at the same time. The bearing cage should not be subjected to external forces under any conditions.

5. Motor bearing vibration and noise level selection

Deep groove ball bearing noise can be transmitted through structural conduction or air media. The rotating deep groove ball bearing itself is the source of the sound source or vibration, causing the bearing vibration or noise to occur mainly from the natural vibration of the bearing and the vibration generated by the relative motion inside the bearing.

Natural vibration - the inner and outer rings of the bearing are thin-walled rings, which have their own inherent vibration modes. Usually, the first natural frequency of the motor bearings is between several KHz.

Vibration generated by the relative motion inside the bearing - the true surface geometry of the inner and outer rings and the surface of the steel ball, such as roughness and waviness, which affect the sound quality and vibration of the bearing, with the steel ball surface having the greatest influence.

5 motor bearing vibration and noise level selection

Deep groove ball bearing noise can be transmitted through structural conduction or air media. The rotating deep groove ball bearing itself is the source of the sound source or vibration, causing the bearing vibration or noise to occur mainly from the natural vibration of the bearing and the vibration generated by the relative motion inside the bearing.

Reprinted from the network