GQZ Technology Knowledge: Current Situation and Direction for Technology Development of Rolling Bearing Products
Antifriction、 lightweight、 unitization、 intellectualization、robustness enhanced and low noise are still an important direction for the technical development of rolling bearing products.
Abstract : From the perspective of global bearing industry，intercepting historical span of nearly 20 years since the be- ginning of 21st century．Based on systematic analysis of leading products produced by world－renowned bearing companies，the current situation for technology development of bearing products is elaborated from technical and product levels．The direction for technology development of bearing products is analyzed from different dimensions of antifriction， lightweight，unitization，intelligence and robustness．The future general development direction and specific development issues are prospected．
Key words: rolling bearing; product; technology; development; current situation; direction
Rolling bearing (hereinafter referred to as bearing) product technology refers to the bearing as a whole category of products, which contains the technical connotation or reflects the technical characteristics, such as high precision, high speed, low noise, high load capacity, long life and high reliability. Behind product technology are specific design technology, material technology, lubrication technology, sealing technology, etc., which belong to the supporting technology of product technology.
The judgment on the directionality, trend and trend of bearing product technology needs to be put under a large concept of time and space in order to better examine, insight and judge. Otherwise, it is only a short-term case in a short period of time and local fields, and cannot form a leading wind vane. Therefore, we must take a long historical span from the perspective of the global bearing industry and systematically analyze and study the leading products of “head enterprise” (world-famous bearing company), so as to sort out a relatively clear direction of technological development.
1. Development status of bearing product technology
1.1 Technological progress and breakthrough
In the 1980s and 1990s, the most prominent mainstream direction of bearing product technology is enhanced type, low noise and long life. In addition, in terms of high precision, in addition to the standard tolerance grades of P4 (high precision grade), P2 (ultra-high precision grade) and SP, UP, P2A and other special tolerance grades, NRRO, namely “non-repeated runout” index, was proposed. In the 20 years since the 21st century, the bearing has reached a new height in the pursuit of high performance and long life.
1.1.1 High performance
In terms of rotating speed, the focus is on the grease lubricated bearing with convenient use, simple maintenance and green environmental protection, and its dm · n value can reach 2.0 × 106mm ·r / min, while the recommended value of grease lubricated bearings in the past was only 0.6 ×106mm·r/min。
In terms of bearing capacity, basically all types of bearings have been improved. For example, the BM coefficient in the calculation formula of bearing rated dynamic load has been adjusted by many companies. Taking the most widely used deep groove ball bearing as an example, the BM coefficient has been increased by 15% on the basis of the original 1.3.
In terms of temperature tolerance, the conventional applicable temperature of bearings is - 40 ~ 120 ℃, but now the low temperature tolerance limit of some general bearings has reached - 55 ℃ (at this temperature, some bearing parts and materials will face the risk of low temperature brittleness, i.e. “cold brittleness”).
In terms of low noise, the type of bearing has been extended from deep groove ball bearing and cylindrical roller bearing to self-aligning roller bearing with “extensive” use requirements.
In terms of friction torque, it has been extended from precision instrument bearing to automobile bearing, household appliance bearing, wind power bearing, industrial gearbox bearing, etc.
In many applications, bearings are required to have “all-round” technical characteristics. The above-mentioned high performance is reflected in the superposition of many specific bearings, that is, the comprehensive performance should be excellent.
High performance is based on the significant progress of related technologies, such as the popularization of bearing CAD technology, the sinking of finite element and simulation design and analysis technology, the deepening of tribology application technology, and the strong support of hardware in materials, equipment and other aspects.
1.1.2 Long life
The fatigue life of famous brand motor bearings and machine tool bearings is enough to meet the requirements without consideration. Motor bearings mostly adopt sealing structure, so the service life of lubricating grease is mainly used as the judgment criterion; Machine tool bearings are mainly based on wear life or precision life.
Automobile bearing: the bearings of key parts such as wheel hub and gearbox are required to have a design life of 10 × 105 km or even 12 ×105 km.
Railway bearing: SKF newly launched axle box bearing, its overhaul (disassembly and overhaul) cycle can be reduced from the conventional 10 ×105 km increased to 17 ×105 km。
Main shaft bearing of shield machine: it is required to have fault free service life of 10000 h or 10 km.
Wind power bearing: the service life is required to be 20 years, which may be the application field requiring the longest service life of the bearing so far.
The most significant contribution to the significant improvement of bearing life is the technological progress of raw materials, such as high-purity vacuum degassing bearing steel in Japan, Europe and the United States, which has reached the fatigue life level of electroslag remelting steel or vacuum arc remelting steel with special smelting methods, including the application of special materials (such as high-temperature steel m50nil, high nitrogen steel cronidur30, etc.) and special heat treatment (such as nano bainite quenching, high residual austenite heat treatment, etc.); Secondly, lubrication (such as long-life lubricant), sealing (such as high-performance sealing structure and materials), structural design (such as enhanced optimization design), precision machining (such as grinding ultra-precision with high dimensional shape accuracy and low surface roughness), quality control (such as ultrasonic nondestructive testing) also play an important role.
In the technical background of long life, some basic research results have brought profound changes and impacts.
In terms of the concept of bearing life, after the evolution from early (infinite life) → long-term (finite life) → recent (infinite life), it is once again established that the bearing has the characteristic of “infinite life”, that is, a large number of test data over decades show that there is a “fatigue limit” in the bearing, and the bearing will not be fatigue damaged as long as it is lower than this stress value or load value. This concept completely overturns the statement that has existed in classical theories and textbooks for more than half a century: no matter how reasonably designed, well manufactured, correctly installed, well lubricated and properly maintained, the bearing cannot run forever and will eventually fail due to fatigue.
In terms of bearing fatigue mechanism, in developed countries of bearing industry such as Europe, Japan and the United States, the bearing fatigue mechanism has changed from “internal origin type” in the first type to “surface origin type” in the second type due to the high purity level of bearing steel. In addition, white tissue (WEA), as the third fatigue mechanism, has also been recognized broadly.
In terms of bearing life calculation: 1) in the international standard ISO281: 2007 rolling bearings - dynamic load ratings and rating life, a new a1 correction coefficient with a reliability greater than 90% is given based on the minimum life theory, and the maximum reliability is extended from 99% to 99.95%. Based on the research results of SKF, the “fatigue load limit” Cu and “bearing life calculation system” are introduced
aIAO life correction factor of “method”; 2) Following the revised bearing life model proposed by SKF in 1989, the generalized bearing life model was proposed in 2015, which separated surface fatigue from subsurface induced fatigue and introduced surface fatigue mode.
In terms of bearing residual life evaluation, NSK initiated the concept of “fatigue index”, and speculated the bearing residual service life through the changes of martensite half height width and residual austenite in the material by X-ray. Schaeffler calculates the remaining service life of the bearing based on the actual load spectrum, that is, the nominal rated life minus the current operating time.
1.2 Product upgrading and innovation
1.2.1 Universal bearings are generally upgraded
The general bearing is also called standard bearing. It seems that it is a bearing with strong universality but low technical content. However, since the beginning of the 21st century, the internationally famous bearing companies have almost upgraded at the same time, such as SKF's Explorer bearing (since 1999) and its upgraded version (since 2011), Schaeffler’s X-life bearing (since 2003), NSK’s HPS (high performance standard) bearing (since 2004), Since 2004, the bearing of ULTAGE (NTL).
For the upgrading of these general bearings, most companies realize the “vertical replacement”, that is, they completely replace the original “standard bearings”, or “redefine the standard bearings”. The improved technical content is mainly to further “improve the bearing capacity and service life of the bearing, reduce the friction torque of the bearing (i.e. increase the bearing speed) and reduce the bearing vibration and noise”. For example, the service life of HPS self-aligning roller bearing of NSK is increased by 2 times and the extreme speed is increased by more than 20%; Taking the ultage deep groove ball bearing of NTN as an example for high-speed servo motor, the service life of grease is increased by about 5 times, the speed is increased by more than 2 times, and the noise is reduced by 3dB (A).
The general bearing has a large quantity and a wide range. The general improvement of its technical performance is equivalent to improving the overall technical level of bearing products from the bottom, which is of great practical significance.
Due to the substantial improvement of the technical quality level of general bearing, the scope of “general bearing specialization” is also expanding. For example, the above upgraded products are widely used in many special bearing fields and have excellent performance. The generalization and enhancement of the phenomenon of general bearing specialization is not only conducive to the mass production of bearing enterprises, but also conducive to the low-cost use and maintenance of bearing users, which will greatly promote the complementarity of technology and economy.
1.2.2 Further innovation and improvement of special bearings
The special bearing directly faces the supporting host and needs to meet various demanding personalized requirements (including extreme working conditions and extreme performance). It integrates many advanced and even cutting-edge technology applications. It is the core product carrier for the bearing industry to focus on performance improvement and scientific and technological innovation.
1) Machine tool spindle bearing. Represented by angular contact ball bearings, SKF has introduced three structural forms: CD, CE and FB3, which are applicable to heavy load, high-speed and ultra-high speed respectively, realizing full coverage of working conditions; Schaeffler developed M series on the basis of RS and HS series, which combines the advantages of the first two series and further improves the reliability; NSK has developed a new generation of “robust” series bearings, which have comprehensive excellent properties such as low temperature rise, anti-bite and long life. Among them, SHX heat-resistant steel for ultra-high speed bearings is more anti bite, wear-resistant and better fatigue life than M50 steel for Aeroengine spindle bearings.
2) Motor bearing. Schaeffler’s new generation of C-type deep groove ball bearing reduces friction torque by 35% and noise by 50%, which is declared to be “a historical milestone compared with the invention of ball grinder in 1883 (the author's note: the symbol of the birthplace of modern bearing industry)”; NSK GR series deep groove ball bearing has the technical characteristics of low energy consumption, smoothness and silence. It is suitable for high-efficiency motors such as air conditioner, vacuum cleaner and CPU cooling fan.
3) Automobile bearing. The 3rd generation wheel hub bearing unit for passenger cars has gradually become a market leading product. The 2nd.5th and 3rd generation tapered roller hub bearing units developed by NSK for pickup trucks, large SUVs and commercial vehicles further improve the reliability and fuel efficiency of vehicles through the application of integration and low friction technology; The flange of SKF's light vehicle hub bearing unit is made of aluminum alloy instead of steel, which can not only reduce the mass by 30%, but also maintain its stiffness and durability in corrosive environment and wide temperature range; Schaeffler's maintenance free tapered roller hub bearing unit for heavy trucks (without replacing seals and grease) has a warranty period of 50 years × 104KM, design life 100 × 104KM, maintenance free for life, while the previous second generation hub bearing unit required only 30 years of design life × 104km，50 × 104km; JTEKT “bearing unit for supercharger for high temperature and high speed” adopts ferrules, cages and ceramic rolling elements of high temperature resistant materials. The rotating speed can reach 250000r / min at the working temperature of 350 ℃, while the traditional bearing for supercharger can only reach 250000r / min at the working temperature of 150 ℃ reach to 50000r/min.
4) Railway bearing. NSK's newly developed double row cylindrical roller axle box bearing is suitable for E5 series high speed bearings with a design speed of 320km / h
High speed train, which can only meet E2 and E3 series trains with design speed of 275km / h; The axle box bearings provided by SKF, Schaeffler, NTN and NSK for China's high-speed railway EMUs can meet the harsh requirements of train operation speed of 200 ~ 350km / h, long routing, high density, wide temperature range and complex geological conditions; Schaeffler’s latest j20g insulated bearing for traction motor, with ceramic ring spraying, can withstand the breakdown voltage of DC 5000v (generally DC1000V in the past, up to DC 3000v), which is the most advanced in the first level world at present.
5) Wind turbine bearing. Wind power bearing is a special bearing with the most rapid development in recent 20 years. Innovative products are mainly concentrated in spindle bearing and speed increaser bearing. The axial wear of Timken type tapered roller bearing can be reduced, i.e. the service life of TIMI type tapered roller bearing can be reduced; SKF's main shaft uses “Nautilus” double row tapered roller bearing unit, which can facilitate connection, reduce weight, reduce friction and improve the reliability of fan operation. Timken's speeder planetary gear integrated flexible pin assembly integrates the gear with the outer ring of the bearing, eliminates the possibility of “race” of the outer ring, improves the bearing capacity of the bearing, and the flexible pin structure also improves the meshing performance of the gear; The high-speed end bearing in the speed increaser of Schaeffler and other companies adopts oxidation blackening coating (blackening) treatment, which can not only reduce the high-speed and light load sliding damage, resist corrosion and improve the adhesion of the lubricant surface, but also effectively prevent the occurrence of white structure cracks. NSK adopts aws-tf steel independently developed, which increases the white structure life by 7 times, the surface peeling life by 3 times and the toughness by 2 times.
6) Other special bearings. The waterproof performance and bearing capacity of NTN sealed four row tapered roller bearing for roll are increased to 2 times and the service life is improved to 1.8 times. Mining machinery bearing -- DuraSpe of TIMKEN ×× the tapered roller bearing of power density series is used in cement vertical mill. The bearing capacity is increased by 28% and the service life is increased to twice that of the original bearing. Compared with the original ca-vs bearing, the service life of ca-vs3 and ca-vs4 self-aligning roller bearings of NSK can be increased by up to 2 times and the rated dynamic load can be increased by 25%.
During this period, the special bearings with large increment in the market segments include wind power bearings, robot bearings, new energy vehicle bearings, high-speed railway bearings and medical device bearings, most of which are based on. It depends on the rapid development of the Chinese market. The development trends of high-power wind power equipment (8mW, 10MW, 12MW or even more) and high-speed driving motor of new energy vehicles also give key parts. Supporting bearings pose no small challenge, and the innovation of various solutions has also greatly promoted the technical level of bearing products to a higher level.
2 Analysis on the development direction of bearing product technology
The main development directions of bearing product technology in recent years can be summarized as follows if analyzed according to different dimensions.
Under the general trend of green development of global economy and society, antifriction (also known as energy saving) has become the most important theme in the technical development direction of bearing products. NTN directly claims that the bearings are “eco products”, i.e. ecological products. The E2 deep groove ball bearing launched by SKF reduces the friction loss by at least 30% even compared with its Explorer bearing; The developed X-Tracker low friction automobile hub bearing unit reduces the friction torque by 25% compared with the traditional hub bearing unit. Taking the application in medium-sized vehicles as an example, it can reduce the CO2 emission of 1.3g/km. NSK GR series deep groove ball bearings reduce the friction torque by 40% ~ 50%. The low friction torque tapered roller bearing continuously developed by JETKT has experienced four generations from 1990 to 2015. From the first generation to the fourth generation, the friction torque is reduced by 10%, 20%, 50% and 65% respectively compared with the standard bearing. Among them, the achievement of the third generation LFT-III has won the Japanese friction Technology Award, and the fourth generation LFT -IV is called “the next generation ultra-low friction torque tapered roller bearing”. From 1980 to 2017, NSK continuously upgraded the tapered roller bearing to the 6th generation, and the cumulative friction torque decreased by about 70%.
Lightweight is not only an implementation path of energy conservation, but also has the value of saving materials. In the objective function of modern mechanical design, lightweight is often a core index, especially for aerospace and aerospace vehicles, the pursuit of mass reduction has reached the degree measured by “grams”. Vehicle lightweight is also one of its key technologies, especially for the “mileage anxiety” of new energy vehicles. In addition to continuously improving the energy density of power batteries, the realization of vehicle lightweight to reduce energy consumption is another solution path of “reverse thinking”. The bearing itself not only contributes to lightweight, but also makes the supporting drive motor, gearbox and other assembly components further lightweight due to compactness, and the effect is more remarkable.
The ultra-light wheel hub bearing unit developed by NTN, which weighs only 1.0kg, is the “lightest” automobile wheel hub bearing unit in the world. Compared with the original products, the radial and axial dimensions of angular contact ball bearings for reducer are reduced by 30% and 25% respectively, and the mass is reduced by 55%. The total mass of SKF light wheel hub bearing unit is reduced by about 30%, while the performance and reliability are still equivalent to the original products.
The bearing with its own lightweight features, such as needle roller bearing, has the unique advantage of replacing other types of bearings. For example, the sealed stamped outer ring needle roller bearing for NSK automatic transmission has a wall thickness of only 1.5mm, which is “the thinnest in the world” and can replace the original sliding bearing (i.e. bushing). With the improvement of speed and other “short plate” performance, the expansion space of needle roller bearing will be larger and larger.
The remarkable progress of modern materials, lubrication and sealing technology has greatly increased the service life of bearings. In other words, under the same service life requirements, bearings with smaller specifications can be used to replace bearings with larger original dimensions - these are also the “open” ideas for realizing lightweight of bearings, not limited to “subtraction” on the overall dimensions of bearings.
The componentization and unitization of bearing products is not a new thing, such as the first, second and third generation automobile hub bearing units, the first and second generation automobile clutch bearing units, computer hard disk drive spindle bearing units, washing machine bearing units, etc. in the early stage, the fourth, fifth and sixth generation automobile hub bearing units, maintenance free heavy truck bearing units and automobile turbocharger bearing units were continuously developed in the later stage, Railway axle box bearing unit, machine tool spindle bearing unit and ball screw assembly bearing unit, engineering machinery planetary gear needle roller bearing unit, wind turbine spindle double row tapered roller bearing unit, etc. Because agricultural machinery requires convenient maintenance and simple replacement, bearing unitization has become a good solution. For example, SKF and Schaeffler have developed a variety of disc bearing units for planters, bearing units for vibrating crankshaft of combine harvester draft by draft, idler bearing units of vibrating screen drive and bridge transmission mechanism, maintenance free plow disc bearing units, etc. the application fields are expanding and the types and varieties are increasing.
In particular, it should be pointed out that the unitization of bearing products is a good development direction, but it cannot be generalized and abused. It is unitized for unitization, not for practical application. The typical case is the 4th generation automobile hub bearing unit, which integrates the hub bearing with flange on the inner and outer ring with constant velocity universal joint, forming two functions of connection and transmission. The creativity is very good, but it has been more than 20 years since it was put forward, and there are few commercial examples. The fundamental reason is that it violates the most basic reliability criterion in mechanical design and combines the two vulnerable parts of hub bearing and constant velocity universal joint, which greatly reduces the use reliability and greatly improves the replacement cost (when the two parts are separated, which one is broken and which one is replaced, no matter which one is damaged after integration, it needs to be replaced as a whole). The 5th and 6th generation automobile wheel hub bearing units actually have the same problems, which is destined to be difficult on the road of commercialization. Therefore, when developing bearing units, we should not only conceive from the structure and function, but also comprehensively consider the service performance, especially the reliability, maintainability and economy, otherwise the market will give the best answer.
The prototype of intelligent bearing is the “automobile hub bearing with ABS anti-lock system sensor” launched in the 1980s, so it was first called “bearing with sensor”. After that, it was gradually extended to many fields, such as railway, wind power, machine tools, robots, servo motors, electric vehicles and motorcycles. At present, the application of intelligent bearing is more prominent in the railway and wind power industry. This is because railway transportation requires high reliability and safety, and its operation state must be monitored at any time. The use of intelligent axle box bearing and intelligent traction motor bearing can easily meet this demand; Wind farms are generally located in remote areas, so manual inspection is very difficult. Using intelligent bearings to remotely monitor key parts such as yaw, pitch, spindle, gearbox and generator can well solve the biggest “pain point” problem in this application scenario.
The most basic monitoring parameters of smart bearing are temperature and vibration. More advanced ones are speed, steering, position, switch, stress, strain, load, torque, etc. relevant functions are also expanding. For example, insight bearing released by SKF in 2013 is an “integrated self-powered sensor suite capable of wireless transmission of bearing status information in real time”, its slogan is “breakthrough innovation in the field of bearing condition monitoring” and “leading to realize the dream of bearing as a mechanical” brain “. Insight into the key technologies of intelligent bearing, including miniaturization, self-power supply, simplicity and intelligent networking, with powerful functions.
Generally, the form of intelligent bearing is to directly embed or hang sensors on the bearing, and the embedded type is more in line with the definition of intelligent bearing itself as a complete product. Therefore, several international famous bearing companies, such as SKF, Schaeffler, NSK, NTN, etc., focus on the independent research and development of such products. Schaeffler launched a vario sensense bearings smart bearing, which is in the form of “standard bearing + sensor cluster”, that is, the overall dimension and structure of the bearing itself remain unchanged, while the sensor cluster combined with it is configured with a variety of different sensors in a modular manner. This idea of making intelligent bearings into a “standardized product” has the idea of industrialization and broad market application prospects.
If the bearing with sensor is called “smart bearing 1.0”, it has entered the era of “smart bearing 2.0”, that is, “from perception to execution”. For example, the smart bearing equipped with “actuator” such as micro motor can realize the full closed-loop processing of state perception, signal acquisition, data transmission, operation analysis and state control.
On the latest Chinese and English bearing samples published by SKF in 2014 and 2018, smart bearing has become a “cover product”, which indicates that the highlight moment of its leading role is coming from another side.
The transliteration of robust or robust ness is robustness, while the free translation is anti-transformation, robustness, robustness, tolerance, etc. it is a late term in the whole engineering and technical field. It has been introduced into the field of bearing industry for a shorter time. It is still a relatively unfamiliar and remote concept until now, but recently it has increasingly become a “high-frequency hot word”. For example, Schaeffler’s MPAX brass solid cage for X-life cylindrical roller bearing adopts “robust design”, which is more resistant to vibration and impact load and suitable for high-speed operation; NSK's latest machine tool bearing is directly called “ro-bust” series, which is not only resistant to burning and sticking, but also has other outstanding properties such as wear resistance and fatigue resistance. One of the design objectives of SKF for compressor and pump bearings is to improve its robustness under non ideal working conditions. NTN's “customized scheme to enhance reliable robustness” has become a technical guideline for wind power gearbox bearings. For the bearings used in construction machinery and agricultural machinery, robustness has become a basic requirement. Similar to these “non-road vehicles”, the working environment is more complex and harsh (bumpy vibration, dust and mud, severe cold and heat). Therefore, the supporting bearings must have strong applicability and tolerance.
2.6 Other aspects
In addition to the above aspects, enhanced and low noise are still an important direction for the technical development of bearing products. Although the technology has been mature and basically reached the top of the current R & D and manufacturing means, it has been continuously improved.
3. Prospect of future development direction of bearing product technology
Combining the current development direction of bearing product technology with the future development trend of modern manufacturing equipment industry, we can make the following prospects for the future.
3.1 General development direction
Among the three technical qualities of bearing “accuracy, performance and service life”, the accuracy has basically reached the top, which can meet the needs of the current stage and the visible future. High performance and long service life are the eternal direction of bearing product technology development, which seems to have no end.
3.2 Specific development issues
1) Energy conservation and emission reduction is a broad consensus and concerted action of the international community to deal with environmental pollution and climate change, and the antifriction of bearings will continue to upgrade.
2) Driven by the mainstream trend of increasing the power density of motor (especially the driving motor of new energy vehicles), compressor and other power machinery, the speed performance of bearing will be further improved.
3) Robustness will become the basic technical requirement of many bearings.
4) Intelligent bearing enables simple machinery to realize digitization and Internet of things. Therefore, intelligent bearing is known as “a product seamlessly connected with industry 4.0”. This concise and direct definition indicates that intelligent bearing has broad development space, and embedded, micro type, multi parameter and multi-function are undoubtedly its main technical characteristics.
5) Tapered roller bearings, which can bear combined radial and axial loads at the same time, have small radial section. They are especially suitable for needle roller bearings with lightweight development trend, deep groove ball bearings and angular contact ball bearings of 18 and 19 size series. Their applications will continue to be expanded.
6) With the wider penetration of sealed bearings convenient for operation and maintenance, the research and development of high-performance (long life, low noise, wide temperature range, environmental protection, etc.) grease will still be a lasting “hot spot”.
7) Cage has long been a “weak link” in bearing research. With the deepening understanding of its restrictive role in the improvement of bearing performance, the research on the design, material and processing technology of new cage will remain highly active.
8) The bearing life theory based on surface fatigue model may soon become a new bearing life calculation criterion and be incorporated into international standards.
9) Based on the application of big data and the improvement of model algorithm, the prediction of bearing remaining life will be more accurate, practical and instrumental.
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With a wide range of designs to choose from, GQZ tapered roller bearings are also customizable to match your specific speed, load, contamination, temperature or vibration conditions.
GQZ Tapered roller bearings feature a cup and cone assembly. The cup is comprised of the outer ring and the cone assembly consists of inner ring, rollers, and cage. This bearing construction accommodates combined loads and provides low friction during operation. By adjusting one single row tapered roller bearing against a second tapered roller bearing and applying a preload, a rigid bearing application can be achieved.
GQZ tapered roller bearings are also made to Explorer class. GQZ Explorer combines our expertise in bearing design, tribology, metallurgy, lubrication and manufacturing. GQZ Explorer tapered roller bearings are typically used in bearing solutions where there is a need to increase performance, reduce friction or increase power density in applications.
Founded in 1999, Wuxi Guangqiang Bearing Trade Co.,LTD, deals with precision bearings and bearing related products across a large spectrum of customers. Since the founding the company, we keep standing by the principle of "Quality First, Credit First, Independent Innovation" and our company has won a great reputation from home and abroad.
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