Bearings are hardware accessories, characterized by sliding bearings, rolling bearings, linear bearings and so on
Although many types of bearings and varieties, and have their own inherent characteristics, but compared with the sliding bearing, but has the following common advantages:
1) bearing friction coefficient is small, so the friction resistance and start friction torque is small, less power consumption;
2) Dimensions have been international standardization, serialization, generalization, suitable for mass production, interchangeability, easy to install, disassemble and repair;
3) bearing internal clearance is very small, high precision, Bearings can be applied by preload to improve bearing rigidity, which is very important for precision machinery;
4) bearing drive high efficiency, less heat, Bearings easy lubrication and maintenance, saving lubricant;
5) load, speed and operating temperature range of a wide range of working conditions, a small amount of changes in the performance of the bearing has little effect;
6) In general, most types of bearings can simultaneously bear radial and axial loads, can simplify the structure.
The role of the bearing is to support the rotation of the shaft and the shaft parts of the rotary parts, and to ensure the rotation accuracy of the shaft to reduce the shaft and the fixed support between the friction and wear. The shaft is a standard part, specifically produced by the bearing factory, Bearings only the selection and combination design. According to the different nature of the friction at work, the bearings are divided into sliding bearings and rolling bearings two categories.
The characteristics of sliding bearings
Sliding bearing work, the shaft and the bearing between the sliding friction, the advantages of sliding bearings are as follows:
(1) simple structure, manufacturing, easy assembly and disassembly;
(2) has good impact resistance and good vibration absorption performance, smooth operation, no noise, high rotation accuracy;
(3) carrying capacity, long service life.
Therefore, sliding bearings in high-speed, precision mechanisms and low-speed heavy load, impact load larger institutions, such as high-speed precision machine tools, Bearings stamping machinery and agricultural machinery in the application of more.
The characteristics of rolling bearings
Rolling bearings rely on the rolling contact between the main components to support the rotating parts, which generally by the inner ring, outer ring, rolling body and cage and other components. The inner ring is mounted on the journal and rotates together, and the outer ring is mounted on the bearing seat. Rolling bearings, Bearings the outer ring on the processing of a raceway, when the inner and outer ring relative rotation, the rolling body that is, the outer ring rolling in the raceway. Commonly used rolling ball, cylindrical roller, needle roller, tapered roller, spherical roller, asymmetric spherical roller and so on.
The retainers are used to separate the rolling elements from each other so as not to interfere with each other. As the rolling body and the inner and outer ring is a point contact or line contact, the surface contact stress, so the inner and outer ring and rolling material should have good contact fatigue strength and impact toughness, the general use of bearing steel, heat treatment , The surface hardness of 61 ~ 65HRC, the surface of the grinding and polishing; cage generally made of low-carbon steel stamping, but also useful non-ferrous metal or plastic.
Compared with the sliding bearings, rolling bearings with a small friction, low power consumption, flexible start, good interchangeability, and thus access to a wide range of applications.