T-Blog, Your Bearing Wikipedia

With the development of mechanical manufacturing industry towards high precision and high speed, the application range of bearings is more and more wide, and the performance requirements of bearings are also higher and higher, especially in some special working environment, metal bearings can not adapt to the demand, or even can not work at all. Because of its low density, high modulus of elasticity, low coefficient of linear expansion, wear resistance, high temperature resistance, corrosion resistance and other excellent properties, ceramic material has become an ideal material for high-speed manufacturing of precision bearings. Advantages and Characteristics of Silicon Nitride Ceramics Although silicon nitride is not the hardest and the most tough material in industrial ceramics, it is considered to have the best mechanical and physical properties in high performance bearing applications. Heat ResistanceGenerally, when the service temperature of steel bearings exceeds 120 ℃, the hardness will decrease and the rolling life will also decrease. Silicon nitride has good temperature characteristics, especially suitable for high temperature environment. Centrifugal ForceThe density of silicon nitride is about 3.24 × 103kg / m3, while the density of bearing steel is about 7.8 × 103kg / m3, which is only about 40% of the density…

Bearing is an important part of mechanical rotation, and its stiffness and working temperature will directly affect the bearing efficiency on the mechanical operation. In order to provide the rotation accuracy of the bearing, increase the rigidity of the bearing device, and reduce the vibration of the shaft when the machine is working, the preloaded rolling bearing is often used, such as the spindle bearing of machine tool. The bearing stiffness is the force required to produce a unit deformation. The elastic deformation of rolling bearing is very small, which can not be considered in most machines. However, in some machines, such as machine tool spindle, bearing Stiffness is an important factor, in which case generally cylindrical roller bearings and tapered roller bearings should be selected. Because these two kinds of bearings are in line contact with the raceway when they are under load, they have small elastic deformation and good stiffness. All kinds of bearings can also be preloaded to increase the support stiffness. Such as angular contact ball bearing and tapered roller bearing, in order to prevent shaft vibration and increase support stiffness, a certain axial force is often applied in advance during installation to make them compress…