Definition
The thrust bearing is a special bearing that is used to withstand the axial force, which is the bearing of the force in the direction in parallel. The thrust bearing is also referred to as a thrust bearing.
Industry Overview
According to the National Bureau of Statistics, there are 1416 companies in China's bearing manufacturing industry (annual sales income of more than 20 million yuan), and the annual production value is 193,211 billion yuan. The year-on-year increased by 27.59%; sales revenue was 1910.97 billion yuan, an increase of 30.30% year-on-year; profit was 12.523 billion yuan, an increase of 26.54% from the previous year. It is estimated that by 2015, my country's bearing production is expected to exceed 28 billion sets, and the main business income is expected to reach 21 billion yuan and become the world's largest bearing production and sales base. At present, my country's bearing industry is mainly facing three major highlights: the industry has low degree of concentration, low research and development and innovation, and low manufacturing technology. First, the industry has low production concentration. In the world's bearing of about $ 30 billion, 8 major multinational companies in the world accounted for 75% to 80%. Two companies in Germany accounted for 90% of their national total, 5 of Japan accounted for 90% of their national total, and 1 56% of the total number of nations of the United States. And 10 largest bearing companies such as my country's wallets, sales only account for 24.7% of the whole industry, and the top 30 production concentration is only 37.4%. Second, R & D and innovation ability is low. The research of basic theories in the whole industry is weak, and the participation is weak, and less original technology, less patented products. Our design and manufacturing technologies are basically imitated, and the product development capacity is low. Although the support rate of domestic hosts reaches 80%, high-speed rail passenger cars, medium and high-end cars, computer, air conditioners, high-level rolling mills, etc. The mainframe and maintenance bearings are basically imported. Third, the manufacturing technology is low. my country's bearing industrial manufacturing process and process equipment technology has slowed slowly, and the number of controls in the car is low, and the level of grinding is low, with only more than 200 automatic production lines nationwide. Advanced heat treatment processes and equipment for bearing life and reliability, such as control atmosphere protection, double refinement, bainite quenching and other coverage, and many technical problems have not made breakthroughs. R & D, steel quality, improvement, lubrication, cooling, cleaning, and abrasive abrasive tools, etc., are still unable to meet the requirements of bearing product levels and quality. Thus, the process capacity index is low, the consistency is poor, and the product processing size is large. The product is unstable and affects the accuracy, performance, life and reliability of the bearing.
Working principle
Power Ball Bearings is a separation bearing, a bearing, a race, and a casing, a steel ball component separation. The axle is a ferrule that is fitted with the axis, the seat is a ferrule with the bearing seat hole, and there is a gap between the shaft; the thrust ball bearing can only withstand axial load, unidirectional thrust ball bearing / b> is only an axial load that can withstand one direction, two-way thrust ball bearing can withstand axial load in two directions; thrust ball bearing cannot limit the axis The displacement, the limit speed is very low, One-way thrust ball bearing can limit the axial displacement of one direction of the shaft and housing, Bidirectional bearing can limit the axis of two directions To displacement. Power Roller Bearings Used to withstand axial loads, radially joint load, but the radial load must not exceed 55% of the axial load. Such bearing friction factors is lower than those of other thrust roller bearings, and the speed is high, and there is a calorie performance. The roller of the 29000 type bearing is a non-symmetrical spherical roller, which can reduce the relative slide of the roller and the raceway, and the roller is long, the diameter is large, the number of rollers is high, the load capacity is high, and the oil lubrication is usually used. Individual low speeds can be lubricated. At design selection, it should be preferred; 80000 thrust cylindrical roller bearings, 90000 thrust cone roller bearings and AXK type thrust roller bearings, can withstand the unidirectional axial load, it The axial load capacity of thrust ball bearing is much larger, and the rigidity is large, and the axial space is small. Pins Cylindrical Roller Bearing and thrust needle bearing Applicable to low speed, thrust cone roller bearing The speed is slightly higher than Thrust cylindrical roller bearing .
Application classification
thrust bearing is divided into thrust ball bearings and thrust roller bearings. The thrust ball bearings are also divided into thrust ball bearings and thrust angles contact ball bearings. The gasket is composed of the ball and the holder assembly, and the roller ring is called the shaft ring, and the roller coil cooperates with the outer casing is called a race. The bidirectional bearing cooperates with the shaft. One-way bearing can withstand the unidirectional axis To load, bidirectional bearing can withstand bidirectional axial load. The mounting surface of the seat has a spherical bearing that has a calm performance, which can reduce the impact of mounting errors. This type of bearing is mainly applied to the automotive steering mechanism, the main shaft of the machine, the main shaft. Thrust roller bearing Divided into thrust cylindrical roller bearings, thrust, roller bearings, thrust, roller bearings, thrust roller bearings. The thrust cylindrical roller bearing is mainly used in oil drilling rigs, iron steel steel machinery. Thrust motion roller bearing Type bearings are mainly used in hydraulic generators, vertical motors, ship propeller shafts, tower cranes, extruders, etc. Threeware tapered roller bearings Such bearing Main use: One-way: crane hooks, oil rig turning ring. Two-way: Rolling steel roll neck. The planar thrust bearing mainly withstand axial load in the assembly, which is widely used. Although the thrust bearing installation operation is relatively simple, there is still an error in actual maintenance, that is, the tight ring and loose ring mounting position of the bearing is incorrect, and the result is lost, and the journal is quickly wear. The tight ring is mounted on the end face of the station, ie the wrong assembly. The inner ring of the tight ring and the journal are combined. When the shaft is rotated, the tightening ring is rotated, and the friction occurs with the end surface of the stationary element, and the friction torque will occur when the friction moment is greater than the inner diameter, which is tight. The ring is forced to rotate with the shaft fit surface, plus the axial neck wear.
Precautions
The thrust bearing should pay attention to the following points. (1) Take a tight ring and loose ring of the bearing (determined according to the inner diameter size of the bearing, the pore size is different from O.1 to O.5 mm). (2) The stationary piece of the unit (ie, the components do not have exercise, mainly means the fitting ligand). (3) No matter what, the pine ring of the bearing should always rely on the end face of the stationary.
Application
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Bearing effect
In terms of its role, it should be supported, that is, the literal explanation is used However, this is only part of its role, supporting its substance, is capable of being able to bear the radial load. It can also be understood that it is used to secure the shaft. Bearing fast easy automation selection is included. It is the fixed axis to make it only to rotate, and control its axial and radial movement. The motor does not work if there is no bearings. Since the axis may move in any direction, the axis can only be rotated when the motor is working. In theory, it is impossible to achieve the role of transmission, but not only, the bearings also affect the drive, in order to reduce this impact, good lubrication must be achieved on the bearing of the high-speed axis, some bearings themselves have lubrication, called pre-lubrication bearing, but Most bearings must have lubricants, which are responsible for running at high speed, because friction not only increases energy consumption, but is more likely to damage bearings. Transforming the sliding friction into scrolling friction is a one-sided because there is something called sliding bearing.
Lubrication
The lubrication of the rolling bearing has reduced the internal friction and wear of the bearing to prevent burning; extend its service life; discharge friction heat, cool, prevent the bearing overheating, prevent the oil from lubricating oil Aging; also prevents foreign matter to invade the inside of the bearing or prevent rust and corrosion.
Lubrication method
Bearing lubrication method is divided into lipid lubrication and oil lubrication. In order to make the bearing function well, first, the lubrication method for the purpose of use, the purpose of use. If only consider lubrication, oil lubricity is dominant. However, gin lubricity can simplify the length of the surrounding structure of the bearing, comparison of lipid lubrication and oil lubrication. Special payment is taken in the lubrication, whether it is oil lubrication or grease lubrication, too little lubrication does not fully affect the lifetime of the bearing, and there is too much to produce large resistance and affect the speed.
Sealed
The seal of the bearing can be divided into two types of self-contained sealing and additional sealing. The so-called bearing self-strap seal is to produce the bearing itself into a sealing performance device. Such as the bearing tape dust cover, sealing ring, etc. This seal is small, easy to install and disassemble, and the cost is relatively low. The bearing external encryption sealing performance device is a sealing device having various properties in the mounting end cap or the like. The bearing external seal is also divided into non-contact sealing and contact sealing. Among them, non-contact seals are suitable for high-speed and high temperature situations, with different structural forms such as gap type, maze, and washers. The contact seal is suitable for medium, low-speed working conditions, commonly used with felt seals, kitchen seals and other structural forms.
Industry Status
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"China Bearing Manufacturing Industry Demand Forecast and Transformation Upgrade Analysis Report" shows that China Bearing Manufacturing Industry Industry 2009-2013 The total output value is increasing year by year. In 2013, the industry achieved industrial output value of 24,9363 billion yuan, a year-on-year increase of 12.92%. The analysis of the data in the past five years has found that the sales revenue of China's bearing manufacturing industry in 2009-2013 also increased year by year. In 2013, sales revenue was 24.7 billion yuan, an increase of 11.80% year-on-year. my country's bearing industry has developed rapidly, and the bearing varieties are less than, the product quality and technical level are low to high, and the industry scale has formed a basic and reasonable professional production system for product categories and production layout.