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It is difficult to name anything more important for equipment and machinery than a bearing. Perhaps only a wheel. They have been spinning together from the times of ancient Egyptian and Roman civilizations solving the main task – reducing friction during the movement. The great Leonardo da Vinci and Galileo Galilei, many outstanding engineers and scientists were involved in the development of bearing designs at different times. Without high-quality bearings, modern engines, cars, agricultural machinery, rail transport, aircrafts, armoured vehicles, machine tools, and virtually all mechanical engineering and even space engineering would not be possible. Nevertheless, there is a wrong idea about the bearing as the simplest assembly being easily manufactured. This is a deeply erroneous view. A modern bearing requires the development of steels and other structural materials with very specific properties, complex heat treatment, optimal internal geometry of contacting elements, unique machine tools that quickly reproduce this geometry by turning, grinding and superfinishing operations with micron accuracy, special coatings, greases and seals as well as the finest technology and quality control devices. A strong bearing industry is a reliable sign of high-tech engineering. Today, one of the most complex bearing assemblies, without which it would be impossible to develop high-speed rail passenger traffic and freight traffic of increased load capacity is a tapered cartridge bearing. Most recently, only a few world leaders in the industry was able to calculate and produce this assembly. Swedish company SKF - bearing company No. 1 in the world, the flagship of bearing innovations (founded in 1907); German company FAG (founded in 1883) being part of the famous Schaeffler Industrial Group; the dominant companies in the American market – Timken and Brenco. By the way, it is the founder of Timken, Henry Timken, who registered in 1898 a patent for a tapered bearing for wheel axles of horse-drawn transport of that time, and a year later founded a company that produces bearings for carriages of the railway transport. Today's cartridge bearing assembly is a closed device assembled and lubricated at the manufacturing plant, fully ready for fitting and providing 800,000 to 1 million km run without any maintenance. The outer racer of a double-row tapered bearing plays the role of a traditional box body, and the loading is transferred from the side frame of the truck through a polymeric wear-resistant insertion to the adapter distributing the load along the outer racer. The cartridge assembly has smaller dimensions and is noticeably lighter than the traditional box assembly, while having a large load-bearing capacity. Due to the more complex structure and production technology, the bearing itself is considerably more expensive than two classic cylindrical bearings inserted into the traditional box assembly, but this is justified in the cost of the life cycle by the absence of an expensive and unreliable system of depot scheduled maintenance with lube replacement and overhaul of rolling elements. A cartridge bearing comes to the world on the threshold of the new millennium in China, which is actively developing high-speed and ultra-high-speed rail transportation, after the USA and Europe. The development of TBU by SKF, which, with the support of the State, establishes a joint venture in China, becomes the state standard for a Chinese cartridge bearing. In Russia, EPK and Brenco establish a joint venture to produce cartridge bearings of American design. In the same 2000's, SKF decides to build a factory in Tver to produce its own cartridge bearings. Timken and FAG are also looking for their place in the huge market of "1,520 space" (the territory of the former USSR with a characteristic track width of 1,520 mm). As a result, despite the former power of the bearing industry (there were more than 30 gas state bearing plants in the USSR), there was no manufacturer in the market of 1,520 mm track ready for own development and production of a cartridge bearing, taking into account the specifics of the operation of "1,520 track space" (railways of the territory of the former USSR). During the Soviet period, Kharkov Bearing Plant (HARP™), being part of the UPEC Industrial Group was the main experimental site for the development of new designs and technologies, developed mainly in All-Russian Research and Development Institute of the Bearing Industry, the leading institute of the bearing industry of the USSR. In Kharkov, bearing steels with unique properties of heat treatment, advanced designs and technologies of cylindrical and ball bearings were mastered. However, by the time of the world's "bearing giants" entering the market of 1,520 mm track with offers to assemble closed tapered bearing onto freight and passenger cars, neither HARP nor Ukrainian Bearing Industry Design and Technology Bureau (UKTBPP) - the main bearing design bureau of Ukraine, being also part of the UPEC Industrial Group, had no developments of cartridge bearing assemblies. And in 2008 the Board of Directors of the UPEC IG decided to establish the Research and Development Center (R&D Center of the UPEC), with the first and main objective to develop energy-efficient cartridge bearings of increased service life for 1,520 mm track. In its activities, the R&D Center of the UPEC relied on the best Kharkov scientific and engineering schools in the field of mechanical engineering and optimal design. The main emphasis was on mathematical modelling of strength and wear, three-dimensional optimization of internal geometry, modelling of basic technological processes and the creation of massive test beds for physical modelling of operating conditions. To automate the development and design processes, UPEC, jointly with the US company RTS (one of the four world leaders of software platforms for supporting engineering activities) implemented the largest in Eastern Europe project for integrated automation of developments in 2009-2010. Designers, calculators, manufacturing engineers, plant managers, Engineering Centers and the Design Bureau of the UPEC obtained advanced specialized software products related to a unified database, corporate libraries and a unified project management program. All this accelerated the development dramatically. The task was not simply to design a cartridge bearing, but to create a structure, materials and heat treatments that would be optimal in the composition of new cars and carriages accepted for use on the 1,520 mm track, and, most importantly, taking into account the specific operating conditions. For this purpose, the dynamics of the train, deformation of the car and the carriage were initially modelled and, as a consequence, the loading conditions of the bearing assembly, taking into account the heavy operating conditions on 1,520 mm track. Nonlinear mathematical models of the finite element method used to analyse and optimize the geometry of a cartridge bearing assembly contained tens of millions of degrees of freedom being record at that time. Every advantage has its "reverse side". One of the key advantages of a cartridge bearing – an eight-year operation period without replacing the lubricant – also has its reverse side. In ordinary box bearings, during maintenance, wear products were automatically removed with the old lubricant. In a closed bearing assembly, wear should be virtually eliminated, because even the smallest particles of metal, gradually accumulating in the lubricant, will work as an abrasive, exponentially accelerating wear and outage of a bearing. This task was solved due to the optimal three-dimensional geometry and perfection of working surfaces minimizing contact stresses and wear rate, optimal arrangement of fibres in the racers and unique lubrication developed by the UPEC in 2011 in cooperation with the German company Klüber Lubrication, the world leader in special lubricants. In addition to record wear prevention indicators, Klueberplex-HARP lubricant has a very low level of hydraulic losses and performance in a wide climatic range from –60°С to +50°С. However, a new effective lubricant includes additives that are found to be incompatible with conventional elastomers used to seal the cartridge bearings. In 2012, jointly with the German company Freudenberg Sealing Technologies (Simrit) and Italian Corcos, special elastomers chemically neutral to the Klueberplex-HARP lubricant were found, and the developed original design of the cartridge seals best combines effective sealing of a cartridge bearing and low mechanical and hydraulic losses, and the performance of a sealing in the same temperature range. But no matter how perfect the theoretical and laboratory developments are, in such a responsible and innovative product as a new bearing assembly for a rolling stock the final word rests always with the running wear tests. For this purpose, the R&D Center has created unparalleled automated test beds that simulate not only standard European, American and GOST test methods, but also the very loading characteristics that are typical for the upper track structure and the flexible design of the 1,520 mm track carriages, including intense dynamic and axial loads, distortions, etc. The original design of the test beds developed at the R&D Center of the UPEC in cooperation with the UKTBPP can simulate the bearing operating conditions in any part of the trackway. To manufacture automation of these test beds, German companies Beckhoff and Bluemenbecker were involved. Bluemenbecker made the developed on the basis of classical hydraulic loaders, and Beckhoff, for the first time in civil engineering, used its unique high-precision multi-tonnage electrodynamic actuators for loading previously used only by NASA. In 2013, the test beds were certified for testing all types of railway bearings. Since 2011, the plants of the UPEC Industrial Group have begun to develop the production of cartridge bearings. The complex optimal geometry of the racers and rollers, along with the high demands for surface perfection and machine tools performance, is the basis for the requirements for the Performance Specification for the development of special grinding and superfinishing equipment by the world's leading machine tool manufacturers: Italian Mechanika Nova (machine tools for internal and external grinding of several surfaces of racers simultaneously), as well as German Modler (roller grinding) and Nagel (roller superfinishing). Jointly with the Czech companies Roboterm and Hydroma, a modern energy-efficient induction heating and punching line for bearing racers has been developed, ensuring an optimal pattern of appearing of the metal fibres on the raceways. Technologies were also mastered and modern equipment was purchased for hard turning, superfinishing of racers, etc. And this long path of one of the most complicated integrated developments of the company was passed - in August 2017, at the test beds of the UPEC Test Center, certified by the National Accreditation Agency of Ukraine, many-month longevity tests of TBU HARP 1520 (150×250) cartridge bearing for innovative cars of increased carrying capacity have been completed with quite successful results. After hundreds of thousands of kilometres of running on the raceways, working sides of the racers and the working surfaces of the rollers, including the convex working ends, required according to the test procedure, no signs of wear were found at all! Now, certification tests of bearing assemblies of other dimension types, including TBU HARP 130×230, in the development and production assimilation of which all the same design innovations and technologies are used that have been tested and confirmed with tests of the TBU HARP 150×250 cartridge assemblies, wait for their turn. In this context, it is necessary to mention the unique development of the UPEC – an energy-efficient closed cylindrical bearing assembly of increased service life, HARP Duplex, intended for the modernization of cars of conventional load carrying capacity. A thousand cars with HARP Duplex bearing assemblies underwent the supervised operational tests in the Russian Railways, which resulted in 2 million km of run without any signs of wear! At the same time, the working temperature of the HARP Duplex bearing assembly was by 20-25°C lower than that of the tapered bearing of the world-famous manufacturer, which reliably indicates a lower friction loss and, as a consequence, high energy efficiency with a noticeable gain in traction. Together with a new development – the plasma hardening of the bearing surfaces of the box - the box assembly with the HARP Duplex bearing now reliably ensures a repair-free run of 800 thousand km (or eight years without maintenance) and is the optimal product for the modernization of cars of conventional load carrying capacity. Thus, the Ukrainian UPEC Industrial Group confidently entered the "elite world club" of the manufacturers of cartridge bearing assemblies of increased service life, steadily demonstrating a combination of age-old engineering traditions, its own innovative developments with the transfer of advanced European technologies.

Right grease has crucial importance for bearing productivity. Is provides thin film between contact areas in the bearing for friction reduction, heat spread and corrosion prevention on the balls and raceways. The grease will effect on maximal speed and temperature, rotational moment, level of noise, and finally, operation life of the bearing. There is a range of greases, depending on the area of application. Mineral and synthetic grease are most often used and oriented for general and high-speed application. The micro-filter editions are used for low-noise applications. There are water resistant types for low or high temperatures. Silicon greases have wide temperature ranges and more stable viscosity when temperature reduces. They are also water resistant and safe for application with the majority of plastics and rubbers (sealed rings etc.), but they aren’t suitable for high loads and speeds. Water-resistant. Perfluorochemical grease and grease PFPE are incombustible, compatible with oxygen and very stable to many chemicals. They don’t enter into a reaction with plastics and elastomers. Many of them have low pressure of evaporation and they are suitable for applying in vacuum. Some of them can endure the temperatures up to 300 ° C. They are often applied for surface protection from sticking and frost-up due to high hydrophobic features. Dry greases are recommended to use where the standard grease can cause contamination, for example, in vacuum environments. Such grease as molybdenum disulfide and tungsten disulfide are applied on balls and raceways of bearings, provide smooth work and higher moving speed. These coverings are resistant to water and diluted acid. They can be powder-like, wax-like and bonded coverings, which are applied with the help of solvent. Damping greases are widely applied in automotive components to prevent crackle and creaks. They also make switches and drives qualitative. They can be applied in slow rotating bearings, like in potentiometers. Greases for food industry meet special sanitary demands. There are two types of greases for cases, where the contact with food is possible and the contact is absent. These greases are steady to washout and cleaning. Grease viscosity Oils with low viscosity and greases are applied, where the low grease performance is required, for example in sensitive tools. The greases with higher viscosity can be recommended for high-loaded, high-speed and vertical applications of shafts. The greases with lower viscosity are preferred for high-speed applications, as they generate less heat. Though, greases often provide much bigger stability than oils, majority of modern greases with low rotational moment can create the indicators of rotational moment similar to oils according to features. Many greases support their consistence in wide temperature range and they are easy for applying. The light instrument grease is used in components with very low rotational moment. The oil also can provide more high speed of work, but, as such grease isn’t retained on one place, it should be applied like a stream, oil bath or oil fog, if the rotations are short. The oil-impregnated phenolic catch or synthetical catch, made of material with very low frictional factor, don’t need continuous outer greasing. These catches are often applied in high-speed tooth bearings with low rotational moment. Plastic greases are oils, which are mixed with thickener to stay inside the bearing. They are usually suitable for high loads and have an evident advantage in providing constant greasing for a long time without technical maintenance. Grease quantity It is necessarily to take into account that big amount of grease may be harmful for bearing. The filling with grease will mean bigger resistance to rotation (higher rotational moment), but still the risk of heating still remains. The free space inside bearing is important for heat emanating from contact area between ball and raceway. As a result the grease excess can lead to premature destruction. The standard filling comes to 25% - 35% of inner space, but can vary if it is required. Small percent can be indicated for high speed component with low rotational moment, while much bigger filling can be recommended for using with low speed and high load. Speed factor of grease Speed factor («DN») is calculated as rotation speed (rpm per minute) x (outer diameter + inner diameter) ÷ 2. Let’s suppose that bearing rotates with a speed 20000 rpm per minute. Inner diameter of bearing is 8 mm and outer – 22 mm. The above mentioned formula gives DN 300 000, so the grease should have factor higher than this number. Many modern consistent greases are suitable for high speeds with nominal 1 mln. DN or more.

In the modern world, virtually no production of equipment, machinery and vehicles can do without the use of bearings. These are relatively small, but extremely important components. After all, the bearings provide the rotation of the shaft or axis, while reducing the energy loss. The highest requirements to the quality and strength of bearings are made in the field of agricultural machinery. This is not surprising, if you recall in what difficult conditions agricultural machinery works. Dust, dirt, moisture, high temperatures and extreme loads during the season are just some of the difficulties waiting for agro-bearings. HARP BEARINGS - THE BEST SOLUTION FOR EFFECTIVE FARMING AND AGRICULTURAL MACHINERY No one knows more about what the bearings for agricultural machinery should be than the specialists of the Kharkov and Oskol Bearing plants that produce bearings under the trademark HARP. Almost seventy years of design and production experience allows the company to create one of the best bearings in the world. Specialists of the plant were able to take into account all the specifics of the work of farmers and created a whole range of products for the agricultural sector - HARP-AGRО bearings and HARP AGRO UNIT bearing units. HARP AGRO UNIT. Bearings of this line proved to be strong, reliable and wear-resistant. Their tightness and dimensional accuracy makes it possible to use these parts in units and agricultural equipment intended for extreme loads. For even greater protection, HARP-AGRO bearings are manufactured with reinforced sealing of increased tightness of X-SHIELD (bearing number is indicated by the K10 index). The seal of increased tightness X-SHIELD is a unique development of HARP, which allows the bearings to function effectively even in extreme conditions for agricultural machinery, in the dustiest, dirty or damp environment. Such durability is achieved due to the fact that in addition to the internal multi-compaction seal with modern lubricants, the outer side of the bearing is metallic, which means that the possibility of hitting straw and dirt in its internal cavity is completely excluded. An additional advantage of such bearings is the separator made of polyamide. The low weight and singular elasticity of this material significantly increase the serviceability of the bearing during braking, acceleration and high loads, as well as with mutual skewing of the rings. HARP AGRO bearings are used by many well-known manufacturers of agricultural machinery. The Rostselmash combine harvesters manufactured at the Krasnoyarsk combine harvester plant, the Gomselmash combine harvesters, tractors manufactured aat the Minsk, Kharkov and Volgograd tractor plants, the Avtokraz and the Chervona zirka are just a small list of recognized industrial giants that complete their products with these high-quality bearings. FINAL SOLUTION FOR MANUFACTURERS AND USERS OF DISK BORONS and other agricultural machines. Another innovative development of the Kharkov Bearing Plant is a range of HARP AGRO UNIT hub bearing units. These are integral, unattended units designed specifically for tillage and sowing equipment. The unique reliability of HARP AGRO UNIT is achieved through the use of three-level protection: • To prevent high soil pressure, a labyrinth dissector is applied to the seal; • Protection against mechanical damage is provided by the Freudenberg Sealing Technologies (Simrit) cassette seal; • Protection from aggressive environmental conditions (humidity, dust, dirt), typical for soil processing, is achieved through a special lip seal built into the bearing; • Undoubted advantage of the assembly for users is its ease of installation, which can be performed even in the field. Special attention deserves the bearing used in the assembly. Its resource is not less than 6000 machine hours. The bearing does not require lubrication, and its ring blanks are hot stamped, which significantly increases its wear resistance. Another important advantage is the possibility of replacing the bearing without replacing the body! In the HARP AGRO UNIT, the replacement of the bearing, if necessary, is not difficult and can be done in any workshop. BEARING CANISTER ASSEMBLIES In 2016, Kharkov Bearing Plant started production of Y-type bearings - YAR, YET, YEL analogues and canister assemblies on their basis. This is a new generation of bearings that has been developed for use in seeding, tillage and harvesting equipment of such world leading manufacturers as John Deere, Claas, Case, New Holland, Lemken and others. In the development of this line, all the features of the design of agricultural machinery of leading manufacturers, as well as the special conditions for the application of these bearings and assemblies were taken into account. This line of products can withstand high temperatures, extreme external conditions as these bearings are able to work under increased loads and have a wide range of applications. A feature of this line is that the bearing and body are completely interchangeable. In addition, the X-SHIELD increased tightness seals and steel protective washer make the bearing inaccessible to dust, dirt, moisture, soil particles and other aggressive components of the environment. In addition to this reliable protection, bearings and bearing assemblies of the new series are equipped with grease nipples for lubricant supply. This innovation frees consumers from the need to periodically lubricate the bearings, and significantly increases their service life. HARP proved that no one else understands the needs of farmers and the peculiarities of the design of agricultural machinery. Its innovative developments in the field serve as are direct evidence that domestic bearings can be of high quality, durable and reliable. And what is more important, the prices for this product for the consumer are much more affordable as compared to imported analogues. LEARN MORE DOWNLOAD BOOKLET Booklet "Bearings HARP-AGRO and bearing units HARP AGRO UNIT"

Kharkov Bearing Plant HARP is the CIS leader in the manufacture of bearings for more than 60 years, and the HARP bearings are branded components, with quality guaranteed by own engineering developments, extremely precise technologies of manufacturing and assembly, metal conforming to the most stringent standards and certification. The best bearing for agricultural machinery - with the sealing of increased tightness X-SHIELD For more than 60 years the plant works for the agricultural market, studying and taking into consideration all the nuances and requirements for agricultural machinery. When developing new bearings there are considered conditions of the machinery operation, as well as structural modifications in the machinery of the CIS leading machine-building enterprises. Today, the plant mass-produces the bearing for agricultural machinery under the brand name HARP-AGRO, several types of which are assembled with improved sealing of increased tightness X-SHIELD (our own patent). Such bearings have the additional index K10 in the bearing’s designation. INCREASED TIGHTNESS It’s not a secret for anybody that agriculture machinery mostly operates in a hostile environment with dust, dirt and moisture. That’s why bearings for combine harvesters and tractors should have a higher tightness in comparison with other machines. The better the bearing is protected with a sealing, the longer it’s durability. X-SHIELD sealing allows the bearing, contacting with the dusty environment, to operate effectively even in extreme conditions of agricultural machinery exploitation and increases the service life of products. EXTERNAL PROTECTION HARP-AGRO bearings with X-SHIELD sealing feature with improved seal design, which ensures not only the increased tightness of the bearing, but also protection against external mechanical impact. The outer side of the K10 sealing is metal, thereby straw moving during operation of the harvester can not damage the sealing or get into the inner cavity of the bearing and prevent its normal operation. POLYAMIDE CAGE HARP bearings with X-SHIELD can be manufactured either with steel stamped cages or polyamide ones. Elasticity and light weight of polyamide cages positively affect the performance of bearings under shock loads, acceleration and braking, as well as at the mutual misalignment of rings. Polyamide cages have high friction and wear properties. RELIABILITY Reliability of HARP-AGRO bearings has been praised by leading CIS agricultural manufacturers, among which are: ROSTSELMASH combines — grain combines Acros, Torum, Vector, Niva; forage RSM, DON; agricultural machinery GOMSELMASH — PALESSE (forage, grain, sugar beet, potato harvesters, reapers); agriculture machinery BOBRUISKAGROMASH. HARP Bearings are chosen by the MINSK TRACTOR PLANT, BORISOV PLANT OF AGGREGATES, BOBRUISK PLANT OF TRACTOR PARTS AND UNITS, and by automotive plants: ZAZ, MINSK AUTOMOBILE PLANT, KAMAZ, AvtoKrAZ and GAS. Using HARP-AGRO bearings with X-SHIELD seal you protect yourself from damages and costly repairs of agricultural machinery that is especially important in the seasonal harvest. Kharkov Bearing Plant HARP is the CIS leader in manufacture of bearings for agricultural machinery engineering companies and a key supplier to transport machine engineering and railway industries. HARP products are also applied in the automotive, mining and electro-technical industries, as well as in mining-metallurgical complex. With Ukraine's largest park of CNC machines, the plant develops annually more than 15 new types of bearings. You can learn more about product range in the catalogue "HARP-AGRO bearings and bearing units " or download nomenclature About X-SHIELD brand read here For more information we invite you to the plant’s site