Angular contact ball bearings can bear both radial and axial loads. Can work at higher speeds. The larger the contact angle, the higher the axial load carrying capacity. The contact angle is the angle between the line connecting the contact points of the ball and the raceway in the radial plane and the line perpendicular to the bearing axis. High-precision and high-speed bearings usually take a 15-degree contact angle. Under the action of axial force, the contact angle will increase. Angular contact ball bearings have raceways on the inner and outer rings, and the inner and outer rings can make relative displacements along the bearing axis. Bearings of this type are particularly suitable for combined loads, i.e. loads acting both radially and axially. The axial load bearing capacity of angular contact ball bearings increases with the increase of the contact angle α. The contact angle is the angle between the line connecting the contact points of the ball and the raceway in the radial plane and the line perpendicular to the bearing axis.
Whether the angular contact ball bearing is installed or not will affect the accuracy, life and performance of the bearing. Therefore, please fully study the bearing installation, that is, please install the bearing according to the operating standards including the following items.
Angular contact ball bearing installation method
1. Clean the bearings and related parts (for grease-lubricated bearings and both sides with oil seals or dust caps, there is no need to clean the bearings with seal rings before installing them.)
2. Check the size and finishing of related parts
3. Installation method
The installation of angular contact ball bearings should be determined according to the bearing structure, size and the matching nature of the bearing components. The pressure should be directly applied to the end face of the ferrule with a tight fit, and the pressure should not be transmitted through the rolling elements. The bearing installation generally adopts the following methods:
The installation of angular contact ball bearings is more complicated than that of deep groove ball bearings. Most of them are installed in pairs and require preloading. Good installation can greatly improve the working accuracy and bearing life of the main engine; otherwise, not only the accuracy will not meet the requirements, but the life will also be affected.
The installation forms of angular contact ball bearings are back-to-back, face-to-face and series.
When installed back-to-back (the wide end faces of the two bearings are opposite to each other), the contact angle of the bearing spreads along the direction of the rotation axis, which can increase the rigidity of its radial and axial support angles, and has the greatest resistance to deformation; face-to-face (the narrow end faces of the two bearings are opposite) During installation, the contact angle of the bearing converges toward the axis of rotation, and its ground bearing angle is less rigid. Since the inner ring of the bearing protrudes from the outer ring, when the outer rings of the two bearings are pressed together, the original clearance of the outer ring is eliminated, which can increase the preload of the bearing; when arranged in series (the wide end faces of the two bearings are in one direction) when installed , the contact angle lines of the bearing are in the same direction and parallel, so that the two bearings can share the working load in the same direction. However, when using this type of installation, in order to ensure
To ensure the axial stability of the installation, two pairs of bearings arranged in series must be installed opposite to each other at both ends of the shaft.
Features of double row angular contact ball bearings
Premium Steel: Ultra-clean steel bearings extend life by up to 80%.
Advanced Grease Technology: Seiko grease for extended life and performance.
Premium Ball: Quiet and smooth operation that keeps running smoothly even with high growth.
Super Finished Raceway: Specially honed to reduce noise and improve lubricant distribution and life.
Contact Angles: 15, 25, 30 and 40 degrees open.
Patented sealing provides resistance to contamination in the harshest environments.
Cage: Available in nylon, steel, copper cage assembly range.
Quality Assurance: 100% tested to ensure the quality of the entire product.
Misunderstanding of Quality Judgment of Angular Contact Ball Bearings
1. Feel the quality of the bearing through the surface. During the process of selling bearings, we found that many customers said that as long as the surface of the angular contact ball bearing is bright, the quality is good, which is wrong. The light on the surface of the imported angular contact ball bearing should be a kind of black light. The reason for this black light is whether the steel used in the bearing meets the standard and its grinding process and the cutting fluid used. The first two are the main ones. .
2. Whether the chamfer is bright or not The chamfer of the angular contact ball bearing does not determine the quality of the bearing, but reflects the processing method of the angular contact ball bearing. The chamfer is black, which means that it has undergone heat treatment such as quenching, which increases the hardness of the bearing. Some people think that the black chamfer is not good-looking because it is not fully processed. This is a misunderstanding.
3. The one-piece cage is better than the two-body cage. Although the new process uses the one-piece cage, it only saves the material of the angular contact ball bearing, and the performance of the rotation is worse than that of the two-body cage. In general, the service life of angular contact ball bearings is related to three factors. One is the quality of imported angular contact ball bearings. The second is the use environment. The third is the installation method.
Analysis of Abnormal Wear of Double Row Angular Contact Ball Bearing Cage
damage phenomenon
Mainly due to the high temperature phenomenon during high-speed operation (over 80 degrees at the positioning bearing gland), the cage wears and breaks, which eventually leads to locking and adhesion, and in severe cases, the roller diameter and bearing box holes are damaged, resulting in large economic losses and labor consumption. material resources.
Cause Analysis
1. Considering the bearing itself
Generally speaking, when the bearing rotation accuracy is low, the clearance is too small, the linear speed of the rolling mill is high, close to the bearing limit speed or exceeding the limit speed, it will lead to high temperature of the bearing, which will lead to a series of problems such as abnormal noise, locking, sticking and so on. . In this incident, the damage to the bearing was all concentrated on the operation side, while the transmission side bearing used the same batch of bearings, which could operate normally without the above problems under the same rotational speed and lubrication conditions. Therefore, the bearing damage caused by the bearing itself can be ruled out temporarily.
2. Size matching
This angular contact ball bearing is installed on the operating side of the roller system, and it mainly limits the axial movement of the shaft and should not bear any radial load. It is the radial clearance of the C3 group. After accounting for this coordination, after the bearing is subjected to radial force during operation, it is all distributed to the main bearing. The angular contact ball bearing does not bear any negative radial load, but only bears the axial load. Therefore, the bearing damage caused by the dimensional fit problem can be ruled out temporarily.
3. Matching problems of end-face contact parts
Carefully check the end faces of the inner and outer rings of the bearing, the damaged bearings basically have abnormal wear on the end faces, and the cage also has serious wear marks. There is abnormal wear on the end face of the boss from the end face of the ring and the outer ring of the positioning bearing in the inner hole of the box, and the surface has pits and thorns. From this, it can be judged that there is serious relative sliding friction between the bearing and the mating contact parts during operation. After the measurement and installation, the outer ring of the bearing is not axially compressed, and there is a gap of 0.5-0.7mm. After the inner ring is locked, there is also a large gap. Therefore, the bearing has a large axial movement during operation. Since the hardness of each accessory is lower than that of the bearing, it is easy to be irregularly worn. When the bearing is subjected to an axial force in a certain direction, the end face The contact surfaces of the opposite mating parts (the end faces have been irregularly worn at this time) cause relative inclination of the inner and outer rings of the bearing. Therefore, the higher the speed, the irregular running of the rolling elements, the larger clamping force and the frequent impact force on the cage, which will cause the wear and tear of the cage.
in conclusion
From the above analysis, we can temporarily judge that the bearing damage caused by the axial fit after installation and the fit of the contact parts in use are the main factors.
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