Modern simulation technology develops rapidly with the wide application of computer.The specific method of this technology is to input the bearing load direction, size, lubrication mode, rotation speed and environmental parameters, as well as the main parameters of the bearing under a certain application condition into the computer at the same time, through calculation, to understand the possible life of the bearing, so as to evaluate whether the bearing design is suitable for use.This test method can greatly shorten the test time, reduce manpower and test funds, and can know the application effect in advance before the bearing is finished manufacturing. It is a fast and easy test method.SKF and NTN have reached the advanced level in the research of bearing simulation test technology. 

Development trend at home and abroad

At present, there are four main bearing test methods at home and abroad: 1. Friction and wear test; 2. Test bench test; 3.All the above test methods are used in foreign countries, but the purpose of application is different, for example, to develop a new product, the first thing is to do friction and wear test.However, if the form of friction and wear does not change much, and only the product size and load condition change, then only the bench, simulation or actual operation test can be done.Some key parts of the foreign new products (such as car hub bearings, etc.) are very strict assessment, must pass the actual operation test, can be approved for supporting use.SKF of Sweden and NTN of Japan have recently studied the bearing simulation test technology, which can only replace the bench, simulation or experiment, in order to shorten the time of product design and speed up the progress of product development.Now, China's bearing industry has carried out friction and wear tests, only luoyang bearing research institute;More than 20 state-owned bearing enterprises such as luoyang bearing research institute, Shanghai axle research institute, hangzhou bearing test center and wafangdian and Harbin have carried out bearing bench tests.There are luoyang bearing research institute, hangzhou bearing test center, luo shaft, xiang shaft and other enterprises that can carry out the simulation test.In order to carry out the actual test, only when the supporting host enterprises put forward this aspect of the requirements of bearing production enterprises will be carried out, such as railway passenger car wheel bearings and car hub bearings.In short, the domestic simulation and actual operation tests are not extensive, should further expand the scope of the host or the actual operating conditions of the scope, for the simulation test as soon as possible on the schedule to make full software and hardware preparation. 

Main research contents and objectives

To simulation experiment was carried out, for some typical types of typical products need to test bench or simulation test, find out the function relationship between the life and working condition of bearing, and then using this relationship, through the computer bearing design and test work, this is usually only for those very important product test.According to the present capacity of our country, the main goal in the next decade is to carry out simulation test research on railway vehicle bearing, automobile hub bearing and high speed grinding machine spindle bearing, and gradually have certain simulation test conditions.The research contents are as follows:

· set up a simulation system on the simulation test equipment of railway vehicle, automobile hub and machine tool spindle. 

· find the mathematical model of railway, vehicle, automobile hub and grinding machine spindle bearing through the typical test data. 

· prepare computer simulation system software. 

Lubrication technology

Technical summary

Rolling bearing in the movement because of the resistance of the bearing wear and tear, failure, grease (oil) and lubrication way of different, to reduce the effect of bearing friction and wear is different.Therefore, lubrication technology has become an important part of bearing technology research.Some people call the grease "the fifth part of the bearing" (the others are the inner ring, outer ring, rolling body, cage). 

The resistance to rolling bearing rotation consists of rolling friction, sliding friction and lubricant friction.Rolling friction occurs when the rolling body rolls on the raceway.Sliding friction appears on the guide surface of the roller body in the cage, the guide surface of the guard edge of the cage, the end face of the roller bearing and the guard edge of the ring.Lubricant friction consists of the internal friction of the lubricant at the contact and the mixing and extrusion of the lubricant.The total friction of a set of bearings is the total friction of rolling friction, sliding friction and lubricant friction.The task of studying lubrication technology is to develop different lubricating grease (oil) and its lubrication mode, so that its bearing resistance is the least, the longest life. 

Development trend at home and abroad

Foreign advanced industrial countries and the common condition of bearing grease (oil), technology and production has been completely pass, has formed a series of varieties and production capacity, the current major trend is the study of improve the performance of some special cases, grease, such as working on improving the space with the vacuum stability of the fluorinated ether grease, climbing move and viscosity-temperature properties, etc.;Another example is low temperature grease. Although it has good effect in application, its lubrication mechanism has not been well explained theoretically.Another example is the study on the use of gaseous lubricants at high temperature (200-4000c).China's current research task of bearing lubrication is extremely heavy, if the funds allow, should focus on the following problems: first, to improve the service life of the existing sealed bearing grease in the room temperature environment;Secondly, improve the vibration performance of low noise bearing grease;Third, the research and development of common working conditions under the bearing grease new varieties, fill the domestic gap. 

Main research contents and objectives

Gap according to the bearing grease in China and abroad, over the next decade the research content and objectives of the grease is: research on ways to improve the life of grease, with sealed bearing to home appliance, such as washing machines, vacuum cleaners, computers, air conditioner, etc.) and difficult to for repair or disassemble the operation accuracy of damage parts of the sealed bearing (precision machine tool spindle, precision instrument shaft, deep-water mechanical transmission system, etc.), make the grease used life is equivalent to mechanical life;The noise reduction of grease is studied to make the noise reduction of low-noise bearings (v3/z3, v4/z4, etc.) reach more than 3-5db;Research and develop 15-20 new grease varieties, forming the basic pattern of bearing grease series in China.Among them, there are about 8-10 varieties of high temperature, normal temperature and low temperature, 5-8 varieties of general medium or extremely high level motor bearing greases and 5-8 varieties of bearing greases under special working conditions such as aerospace and navigation. 

Sealing technology

Technical summary

Newly developed rolling bearings are fitted with corresponding sealing devices on both ends.Its function on the one hand is to protect the grease (oil) inside the bearing in use will not lose, to ensure that the bearing is in a state of lubrication;The other is to protect the bearing, so that external dust or harmful gas will not enter the bearing cavity, so as not to cause damage to the bearing.Common are rubber or engineering plastics seal ring, also have steel plate made seal ring (or called dust cover).The sealing structure is various, the sealing effect is not the same.If there is a gap between the sealing ring and the bearing, it is called non-contact seal. The smaller the gap is, the better the sealing effect is, but the smaller the speed area of the allowable shaft is.If there is no clearance between the sealing ring and the bearing, it is called contact seal. The larger the contact area of the sealing ring contact lip, the better the sealing effect, but the smaller the speed of the allowed shaft.The sealing technology is mainly to research and develop the corresponding sealing devices applied in different working conditions and the compatibility of the sealing ring material with the corresponding grease. 

Development trend at home and abroad

Several major bearing companies in Japan (seiko, toyo, etc.) represent the direction of bearing sealing technology development.They have a long history in the development of sealing technology and bearing device technology, research depth, the current sealing technology is relatively mature.From the single seal lip to the multi-seal lip, from the contact seal to develop non-contact seal;From the product type, ball bearings, roller bearings are.Following the international development trend, China has also developed the deep groove ball bearing with sealing ring, water pump bearing, railway (tapered roller) bearing, needle roller bearing and short cylindrical roller bearing several kinds of bearings, among which the deep groove ball bearing produces the largest output and has the widest application.According to the recent inspection results of the sealed bearing quality in China by the state bureau of technical supervision, the structural design problems of the sealed bearing in China are relatively large, the sealing effect is not good, the grease leakage phenomenon is serious, the user reaction is strong.Through analysis, the main reason is that China's current seal ring design structure is not reasonable, the inner ring without sealing groove, plus the manufacturing accuracy is not high.Therefore, the future development trend of bearing sealing technology in China is: taking the deep groove ball bearing as the representative, carry out sealing technology test to find the best seal ring structure and the best seal clearance;Carry out research on sealing materials, search for materials that can resist abrasion, aging, high temperature and corrosion, lay the technical foundation for improving the service life of contact seals and developing sealing rings that work under high temperature or harmful atmosphere. 

Main research contents and objectives

According to the current our country the status quo of the poor quality of the sealed bearing, the main research content is: the first is to strengthen research and testing, screening of deep groove ball bearing seal structure and development of the corresponding bearing inner ring seal groove structure, the current deep groove need bearing seal structure upgrade, to make this kind of bearing seal performance in 2005 to catch up with the international advanced level of similar products in the late 1990 s;Secondly, combined with the development of China's car industry, the development of high temperature seal bearings suitable for long-term work at the temperature of 120-1800c;The third is the railway rolling stock bearing as the representative of the development of cone, cylindrical roller bearing series of sealing structure. 

The noise reduction technology

Technical summary

Bearing noise is an important pollution source of the environment and an important indicator for the bearing industry to control, especially for household appliances, office machinery, instruments and meters.In the past ten years, China's bearing industry has done a lot of work to reduce the bearing noise, so that the bearing noise reduction level has been greatly improved, but compared with foreign countries, there is still a certain gap, users reflect the outstanding is the "abnormal sound" problem, that is, the bearing operation of an irregular sudden sound, even screams.Many factors that affect bearing noise, is also very complex, needs from the integral design of the bearing, bearing of every part, inner ring and outer ring, cage, roller and lubricating oil (fat) to analysis and study, also need from each bearing parts in the course of used materials, processing technology and engineering equipment, process materials, etc to analysis and research.This is the basic content of bearing noise technology. 

Development trend at home and abroad

Technology development is endless, although the foreign advanced bearing company (NSK, SKF, etc.) bearing noise levels are high, but still put forward the development direction of further, namely to "mute" bearing development, bearing products in China over the next decade in noise technology development trend is: one is the solution of bearing "sound", the second is the decreasing vibration level on a new step, namely, catch up with the foreign advanced industrial countries bearing the level of the late 1990 s. 

Main research contents and objectives

In order to solve the problem of bearing "different" and make a new step, decreasing vibration level increase amplitude limit control on technical standards, therefore, the main research content is to improve the roller surface and the roundness of ring raceway, solve the cage between the roller and guide the stability, at the same time reduce the impurity particles degrees of grease (oil), and the corresponding balance of rolling contact surface affinity.The roughness control degree of rolling body and raceway is required to be up to 0.001p m;The impurity particles of the grease should not be greater than 0.01 m.To improve the roundness of the ball and socket of the cage, the cross momentum accuracy between the cage and the rolling body can reach 0.01 m.