Influence of Angular Contact Ball Bearing Checking on Its Use
The shaft parts of machine tools, especially the spindle, are generally assembled with thrust ball bearings and rotate at a high speed, sometimes generating high heat. If this phenomenon is not eliminated in time, it will cause the angular contact ball bearing to overheat and cause the temperature of the corresponding parts of the machine tool to rise, resulting in thermal deformation. In serious cases, the height of the spindle and tailstock will be unequal, which will not only affect the accuracy and machining accuracy of the machine tool itself, but also burn out the bearing.Influence of Angular Contact Ball Bearing Checking on Its Use
Rated fatigue life refers to the total number of revolutions when a group of bearings of the same model are operated under the same conditions, and 90% of the angular contact ball bearings do not appear peeling caused by rolling fatigue. When the rotating speed is constant, the rated fatigue life is usually expressed by the total running time.
When studying the service life of thrust ball bearing, we should not only consider the fatigue life, but also consider several service limits according to the performance of the bearing. For example, grease life of grease lubricated bearings. The noise life, wear life, etc. are based on different purposes, and the use limit benchmarks are different. Therefore, the empirical limit is mostly selected in advance.Influence of Angular Contact Ball Bearing Checking on Its Use
Therefore, only investigating the damage of angular contact ball bearing, it is difficult to know the real cause of the damage. However, if we know the use machinery, service conditions, the structure around the bearing, understand the situation before and after the accident, and investigate the damage state of the bearing and several causes, we can prevent the recurrence of similar accidents.Influence of Angular Contact Ball Bearing Checking on Its Use
The judgment of availability of angular contact ball bearing is mainly determined by considering the degree of bearing damage, mechanical performance, importance, operating conditions and the period until the next maintenance. If there are the following defects, it can no longer be used, and the thrust ball bearing must be replaced with a new one. There are cracks or notches on any one of the inner ring, outer ring, rolling element and cage.Influence of Angular Contact Ball Bearing Checking on Its Use
Wear failure is one of the common failure modes of various bearings. According to the wear form, it can be divided into common abrasive wear and adhesive wear.Influence of Angular Contact Ball Bearing Checking on Its Use
Oil film resistance diagnosis technology
Features: the same evaluation standard can be used for different working conditions. The diagnosis effect of surface peeling, indentation, crack and other abnormalities is poor.
Scope of application: suitable for occasions where the rotating shaft is exposed.Influence of Angular Contact Ball Bearing Checking on Its Use
2. Vibration diagnosis technology
Features: vibration diagnosis technology is widely used; Online monitoring can be realized; The diagnosis is fast and the diagnosis theory is mature.Influence of Angular Contact Ball Bearing Checking on Its Use
Scope of application: especially suitable for fault monitoring of angular contact ball bearings in rotating machinery.Influence of Angular Contact Ball Bearing Checking on Its Use
3. Ferrography diagnosis technology
Features: the machine does not need to be disassembled; Low investment and good effect; The early fatigue failure of oil-free bearing can be found; The wear mechanism can be studied.Influence of Angular Contact Ball Bearing Checking on Its Use
Scope of application: it is applicable to the fault diagnosis of angular contact ball bearings lubricated with lubricating oil. It is difficult for bearings lubricated with grease.
4. Temperature Diagnosis Technology
Features: simple diagnosis; The judgment effect of bearing burn is good.
Scope of application: it is suitable for simple routine diagnosis of bearings in machines.
5. Optical fiber monitoring and diagnosis technology
Features: high sensitivity of optical fiber displacement sensor; The signal is directly extracted from the surface of oil-free bearing to improve the signal-to-noise ratio; It can directly reflect the manufacturing quality, surface wear degree, load, lubrication and clearance of angular contact ball bearing.Influence of Angular Contact Ball Bearing Checking on Its Use
Scope of application: suitable for machines that can install sensors in bearing pedestal.
6. Acoustic emission diagnosis technology
Features: rapid and simple diagnosis; It can be monitored online.
Scope of application: the new technology developed in recent years is rarely used in bearing condition monitoring.
When taking the oil-free bearing directly by hand, fully wash the sweat from your hands and apply high-quality mineral oil before operation. Pay special attention to rust prevention in rainy season and summer. Under some special operating conditions, the service life of angular contact ball bearing can be longer than that of traditional calculation, especially under light load. These special operating conditions are the surface damage that may be caused when the rolling surface (track and rolling parts) is effectively separated and limited by a lubricating oil film. In fact, under ideal conditions, the so-called permanent bearing life is possible
It is not allowed to punch with force, directly knock the bearing with a hammer, and transfer pressure through the rolling element.
As soon as the angular contact ball bearing rotates, the raceway surface of the inner ring and the outer ring is in rolling contact with the rolling element, so the running track is a dark surface. The running track attached to the raceway surface is not abnormal, so the load conditions can be known. Therefore, please pay close attention to and observe the running track of the raceway surface when disassembling the oil-free bearing.