We use at least 200 bearings every day in our lives. It has changed our lives. Now scientists are also endowing bearings with a wise brain, so that it can think and speak. In this way, for the precision bearings on the high-speed rail, people can also understand all the status of the bearings without maintenance. With the rapid development of science and technology, the pressure on bearings has become stronger and higher, and the quality requirements will also become higher.
The concept and classification of rolling bearings
Common rolling bearings are generally composed of basic elements such as two rings (ie inner ring, outer ring), rolling elements and cages.In order to apply to some special requirements, some bearings will increase or decrease some parts.
Four Functions of Rolling Bearings
The inner ring is usually a tight fit with the shaft and rotates with the shaft.
The outer ring usually cooperates with the bearing seat hole or the shell of the mechanical part to play a supporting role.
The rolling elements are evenly arranged between the inner and outer rings with the help of the cage, and its row shape, size and quantity directly determine the bearing capacity of the bearing.
The cage evenly separates the rolling elements and guides the rolling elements to move on the correct track.
“Thrust needle roller bearings”
Separable bearings are composed of raceway rings, needle rollers and cage assemblies, and can be combined with stamped thin raceway rings (W) or cut thick raceway rings (WS). Non-separable bearings are integral bearings composed of precision stamped raceway rings, needle rollers and cage assemblies. This type of bearing can withstand unidirectional axial load. It takes up small space and is conducive to the compact design of the machine. Most of them only use needle roller and cage components, and use the mounting surface of the shaft and the housing as the raceway surface.
This type of bearing is equipped with truncated truncated rollers, which are guided by the large ribs of the inner ring. In the design, the vertices of the conical surfaces of the inner ring raceway surface, the outer ring raceway surface and the roller rolling surface intersect at a point on the bearing center line. Single-row bearings can bear radial load and one-way axial load, and double-row bearings can bear radial load and two-way axial load, and are suitable for bearing heavy load and impact load.
“Cylindrical Roller Bearings”
Cylindrical roller bearings can be divided into single-row, double-row and multi-row cylindrical roller bearings according to the number of rows of rolling elements used in the bearing. Among them, single-row cylindrical roller bearings with cages are widely used. In addition, there are cylindrical roller bearings with other structures such as single-row or double-row full complement rollers.
Single row cylindrical roller bearings are divided into N type, NU type, NJ type, NF type and NUP type according to the different rib of the ring. Cylindrical roller bearings have a large radial load capacity, and can also bear a certain one-way or two-way axial load according to the structure of the rib of the ring. NN type and NNU type double row cylindrical roller bearings are compact in structure, strong in rigidity, large in bearing capacity and small in deformation after being loaded, and are mostly used for the support of machine tool spindles. FC, FCD, FCDP type four-row cylindrical roller bearings can withstand large radial loads, and are mostly used in heavy machinery such as rolling mills.
This type of bearing is equipped with spherical rollers between the outer ring of the spherical raceway and the inner ring of the double raceway. According to the different internal structures, it is divided into four types: R, RH, RHA and SR. Since the arc center of the outer ring raceway is consistent with the bearing center, it has the self-aligning performance, so it can automatically adjust the shaft misalignment caused by the deflection or misalignment of the shaft or the housing. Can bear radial load and bidirectional axial load. In particular, the radial load capacity is large, and it is suitable for bearing heavy loads and shock loads. Metal processing WeChat, the content is good, it is worthy of attention. Tapered bore bearings can be assembled and disassembled on the shaft by using fasteners or withdrawal sleeves. Spherical roller bearings can bear a large radial load, but also can bear a certain axial load. The outer ring raceway of this type of bearing is spherical, so it has self-aligning performance. When the shaft is bent or inclined under force, so that the relative inclination of the center line of the inner ring and the center line of the outer ring does not exceed 1°~2.5°, the bearing can still work. .
Thrust roller bearings include thrust spherical roller bearings, thrust cylindrical roller bearings and thrust tapered roller bearings. Thrust spherical roller bearings can bear both axial and radial loads, but the radial load shall not exceed 55% of the axial load. Another important feature of this type of bearing is its self-aligning performance, which makes it less sensitive to misalignment and shaft deflection. Just load P and P. No more than 0.05C, and the shaft ring rotates, the bearing allows a certain range of self-aligning angle. Small values are suitable for large bearings, and the allowable alignment angle will decrease as the load increases.
“Spherical Bearings”
Insert spherical bearings are preferably used in applications requiring simple equipment and components, such as agricultural machinery, transportation systems or construction machinery.
Angular contact ball bearings can bear radial load and axial load at the same time, and can also bear pure axial load, and the limit speed is high. The ability of this type of bearing to bear the axial load is determined by the contact angle. The larger the contact angle, the higher the ability to bear the axial load.
Post time: Jan-25-2022