Writer: Eric Bearing Limited
At present, high-precision, high-speed NSK bearings mainly include: deep groove ball bearing series, single row cylindrical roller bearing series, angular contact ball bearing series and cross roller bearing, these types of products are not only excellent in material selection, but also processing technology The advanced level ensures that the bearing has the characteristics of high reliability and long life. The main application industries of NSK high-precision high-speed bearings are as follows:
NSK robot bearings
Robot R & D and production industry: NSK cross roller bearings are used the most, with high precision and high speed, and the bearing rigidity is outstanding. Under the influence of the robot's high frequency slewing force, the bearing is not prone to micro deformation and has good stability.
NSK high-speed wire rod metallurgical equipment bearings
High-speed wire rod metallurgical equipment: NSK cylindrical roller bearings, NSK diagonal angular contact ball bearings, NSK deep groove ball bearings, these three types of bearings are mainly used in high-speed wire rod mills.
NSK precision CNC machine tool bearings
Precision CNC machine tools: mainly NSK angular contact ball bearings, such as 7 series bearings, example model 7210CTYNSULP4 bearings; BNR, BAR, BER, BTR series electric spindle bearings, example models 95BNR10STYNDULP4 bearings; N series cylindrical roller bearings: N1017TRP4 bearings.
NSK photovoltaic power generation equipment bearings
Photovoltaic power generation equipment mainly includes: silicon rod / silicon ingot manufacturing equipment, silicon wafer / wafer manufacturing equipment, cell wafer manufacturing equipment, crystalline silicon battery module manufacturing equipment, thin film module manufacturing equipment, etc. These equipment have high processing accuracy and load Larger, and often have higher speeds, the NSK bearings used are mainly cross roller bearings (the outer ring is in the form of gears).
NSK Aerospace Equipment Bearing
Aerospace field: Mainly bearing ceramic structure products, with high speed, low friction, no need for lubrication, corrosion resistance, high temperature resistance, insulation, etc., can meet the requirements of aerospace equipment for safety and high reliability.
Understand the rigidity of NSK bearings
The rigidity of the bearing refers to the elastic deformation between the rolling element and the raceway contact surface under load. The small amount of deformation is called "high rigidity"; the large amount of deformation is called "low rigidity", that is, the rigidity is poor. Under normal circumstances, due to the different contact area, the deformation of the roller bearing under load is smaller than that of the ball bearing, and the former is better in rigidity.
Normal understanding, the greater the rigidity of NSK bearings, the better. Because of the poor bearing rigidity, an excessive amount of deformation will occur between the rolling element and the raceway contact surface, which will increase the bearing friction and reduce the bearing rotation accuracy. For example, under load, the amount of deformation between the rolling elements is large, and the degree of deformation is different, which will cause uneven stress on the bearing, which will cause more serious damage to the bearing.
At present, the bearing steel used for bearing production is mostly: high carbon chromium steel, with good rigidity. Among them, the amount of carbon content will directly affect the rigidity of the bearing, but whether it is high-carbon chromium steel or low-carbon chromium steel, the rigidity of the 45TAC100B bearing must meet the on-line standard. For example, the lowest rigidity standard for bearing materials is 100, and the rigidity of low-carbon chromium steel cannot be lower than this value.
Under normal circumstances, the equipment does not have too high requirements for the rigidity of the bearing, and there is no need to be too cautious in the bearing selection process. However, working environments that require particularly high speeds and rotation accuracy require external forces to increase the rigidity of bearings, such as those used on machine tool spindles, machining center spindles, and electric spindles. The measures to increase rigidity include the following two points:
1.Apply pretension to NSK bearings. By preloading, the bearing structure is more compact, and the mutual support between the accessories is improved. When a large load is applied, the load on the roller will be reduced.
2.Adjust the combination form to increase bearing rigidity. In this case, several bearings are regarded as a whole, and the load is reasonably distributed by adjusting the matching form between the bearings or selecting different bearing types. As a whole, the rigidity has also been improved.
How to reduce the running noise of NSK bearings
The noise is directly caused by the vibration, and the Japanese bearing as the assembled transmission component, in the case of rotation, collision and friction between the parts, and the occurrence of vibration is unavoidable. Therefore, it is normal for the bearing to rotate and accompanied by noise. The noise can be reduced, but it cannot be eliminated.
NSK bearing noise includes: running noise and fault noise, and with the development of social civilization, the appeal for noise reduction, energy saving and emission reduction is getting higher and higher. The content to be described in this article is mainly to reduce the noise of the normal operation of the bearing. Because the fault noise is mostly an emergency event, it is not the main component of the bearing noise, so it will not be introduced too much.
First, internal measures to reduce NSK bearing noise (fundamental measures).
1.The material of bearing production needs to be continuously updated, and high-purity steel should be selected as much as possible, which is beneficial to the smoother and smoother surface of the bearing component after processing.
2.Bearing processing technology needs to be improved and improved, mainly the improvement of heat treatment technology and quenching technology. These two processing technologies have the most direct impact on the quality and performance of NN3021MBKRCC1P4 bearing.
3.The bearing finishing process needs to be rigorous. After the rough forming of the bearing assembly, it needs to be ground and dimensioned; afterwards, rough grinding and fine grinding are required, which is a process of narrowing the tolerance; finally, grinding is required. The process of surface cleaning and polishing. Every link is very important and needs to be carried out strictly and carefully.
4.The perfection of bearing assembly technology and the degree of coordination after bearing assembly have a great influence on the beating and vibration of the bearing. Therefore, after the bearing is assembled, super-precision treatment is required to prevent the bearing assembly clearance from being too large or too small.
Above, the content described is the theoretical knowledge that can achieve noise reduction during the production of bearings, and it is also a fundamental measure, but it is not practical in applications.
Second, external measures to reduce NSK bearing noise (practical measures)
Choose the correct tools and methods for assembly, try not to use the cold installation method of hammering, it is easy to cause damage to the bearing, thus causing unnecessary noise.
When conditions permit, effective preloading can be used to minimize bearing clearance. Because, the smaller the clearance of NSK imported bearings, the more compact the bearing fit, the less likely to be runout.
3.Try to choose grease lubrication
Because the lubricating oil film formed by grease lubrication is thicker than oil lubrication, it can reduce the friction between the various components of the bearing and slow down the jitter of the bearing.
4.Regularly clean the bearings
And change the lubricant to ensure that the bearing has a relatively clean operating environment. The situation of noise caused by the intrusion of impurities is also relatively common.