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One article to know about bearing cages
Bearing cage, also known as bearing retainer, refers to the bearing parts that partially wrap all or part of the rolling elements and move with them to isolate the rolling elements, and usually also guide the rolling elements and keep it in the bearing.The main functions of bearing cage:1. Keep a proper distance between the rolling elements to prev... Bearing cage, also known as bearing retainer, refers to the bearing parts that partially wrap all or part of the rolling elements and move with them to isolate the rolling elements, and usually also guide the rolling elements and keep it in the bearing.The main functions of bearing cage:1. Keep a proper distance between the rolling elements to prevent the rolling elements from contacting each other to reduce friction;2. Make the rolling elements evenly distributed, so that the load is evenly distributed;3. Guide the rolling elements in the no-load area to improve the rolling conditions in the bearing and prevent damaging sliding.Types of bearing cagesBearing cage is divided into stamped cage, solid cage and pillar cage.1. The advantages of stamped cage are light weight and large inside space, which can facilitate the entry of lubricant.2. The solid cage can usually allow a higher speed. When the bearing has other forms of movement at the same time, especially at high speed, a machined metal cage should also be used;3. The pillar cage is lighter and can accommodate more rollers. It is only used for extra large roller bearings.Materials of bearing cagesThe cage materials mainly include stamped steel, machined steel, stamped brass, machined brass, polymeric materials, etc.The stamped steel cage has high strength, which can reduce friction and wear through surface treatment.Machined steel cages are generally used for extra large bearings or when brass cages are not suitable.Stamped brass cages are used for small and medium-sized bearings.Machined brass cages are generally not affected by bearing lubricants and can be cleaned with ordinary lubricants. Brass cages should not be used at operating temperatures above 250 ° C.Compared with metal cages, cages made of polymeric materials (nylon 66, nylon 46) have many advantages such as good toughness, excellent friction and wear resistance, high impact resistance, acid resistance and corrosion resistance, etc.  View Details
How much do you know about wind turbine bearing?
                                       In recent years, wind power in emerging markets around the world has developed rapidly. Against the backdrop of national policy support and tight energy supply, China's wind power equipment manufacturing ind...                                        In recent years, wind power in emerging markets around the world has developed rapidly. Against the backdrop of national policy support and tight energy supply, China's wind power equipment manufacturing industry has risen rapidly, and the market demand for wind power equipment has grown rapidly, which has also driven the development of wind turbine bearings. Bearings are the core components of wind turbines. Wind turbine bearings range from bearings used in blades, main shafts and yaws to high speed bearings used in gearboxes and generators Main features of wind turbine bearings 1. Bad use environment. 2. High maintenance cost. 3. High requirement of service life. Bearings for wind turbines mainly include yaw bearings, pitch bearings, spindle bearings, gearbox bearings, and generator bearings. Generator bearing Bearing type: deep groove ball bearings, angular contact bearings. Working conditions: high speed (1000-1500rpm), high temperature (90-120 °C) heavy load. Grease requirements: excellent shear stability, good oxidation stability, good wear resistance, excellent low temperature start-up performance. Spindle bearing Bearing type: tapered roller bearing, spherical bearing. Working conditions: low speed (<25rpm), wide temperature range, heavy load, vibration, high humidity. Grease requirements: excellent wear resistance, good oxidation stability, excellent low temperature start-up performance, good water resistance and so on. Pitch/yaw bearing Bearing type: four point contact ball bearing Working conditions: wide temperature range, heavy load, vibration, high humidity. Grease requirements: excellent corrosion resistance and wear resistance, excellent low temperature start-up performance, good water resistance, good oxidation stability, etc. Each wind turbine equipment has 1 set of yaw bearing and 3 sets of pitch bearing (not equipped for the wind turbine below MW), 3 sets of generator bearings (deep groove ball bearings, cylindrical roller bearings), 2 sets of spindle bearings (spheroidal roller bearings), totally 9 sets. In addition, there are also gearbox bearings. The gearbox has three structural forms. The first type requires 15 sets of bearings, the second type requires 18 sets of bearings, and the third form requires 23 sets of bearings. Thus, the average number of wind turbine bearings is 27 sets. The structural forms of bearings for wind turbines mainly include four point contact ball bearings, cross roller bearings, cylindrical roller bearings, spherical roller bearings, and deep groove ball bearings. The yaw bearing is installed at the connection between the tower and the cockpit, and the pitch bearing is installed at the joint of the root of each blade and the hub. Wind power bearing production process 1. Control the forging temperature. 2. Control the modulation process to ensure the mechanical properties. 3. Control the depth of the intermediate frequency quench hardened layer on the surface. 4. Avoid micro cracks on the surface. The cleaning process of wind power bearing: 1. Inspection of forging blank 2. Rough turning 3. Finish turning 4. Molding finish turning 5. Heat treatment 6. Gear-hobbing and gear-milling processing 7. During drilling, according to customer requirements, it can be treated with blue, phosphating and vulcanization. 8. Rough grinding and fine grinding 9. Demagnetization, cleaning, assembly, surface coating, grease filling,packaging View Details
The main cause of damage to the cage of the rolling bearing
                                       1.Vibration When the bearing is under vibration, the force inside the bearing may cause fatigue cracks in the cage. Gradually, this crack will cause the cage to rupture. To prevent this, bearings with special c...                                        1.Vibration When the bearing is under vibration, the force inside the bearing may cause fatigue cracks in the cage. Gradually, this crack will cause the cage to rupture. To prevent this, bearings with special cages can be used. 2.The speed exceeds the design requirements If the bearing is running at a speed which the cage can not hold, the inertial force will cause the cage to rupture. There are high speed bearings manufactured specifically for this type of use. 3.Wear Improper lubrication or hard foreign objects can cause wear on the bearing cage. Sliding friction is most likely to occur when the rolling bearing is running. However, the sliding contact between the roller and the cage is usually not eliminated, so if the lubrication is poor, the cage is the first part which will be worn. Moreover, the cage is made of a softer material, so the wear is quite fast. Gradually the gap of the cage will cause the cage to break quickly. The same happens when hard particles penetrate the bearing. 4.Foreign matters stuck The particles of parts may be stuck between the cage and the roller, which will prevent the rolling elementg from rolling and then cause the cage to break. As long as it can prevent large foreign objects from intruding into the bearing, the cage can be safe even in heavy load. View Details
Technical features of 71800 series bearing
                                       ZYS 71800 series of ultra-precision angular contact ball bearings provide optimum performance in applications with small cross-sections, high stiffness, high speed and high accuracy requirements, especially for ...                                        ZYS 71800 series of ultra-precision angular contact ball bearings provide optimum performance in applications with small cross-sections, high stiffness, high speed and high accuracy requirements, especially for machine tools, multi-axis drills, robotic arms, measuring tools and other applications. The existing standards for the 71800 and 71801 series are supplied with all-steel and hybrid ceramic ball bearings. ● Optimize the raceway curvature radius of the ring for easy installation and improvement of mounting accuracy. ● Speed performance is improved. ● Product size specifications increase. ● Advanced heat treatment processes maximize the dimensional stability and hardness of bearing part and then reduce wear. ● Designed with multiple preload levels to meet speed and rigidity requirements for a variety of applications. View Details
Slewing bearing (turntable bearing) selection calculation method
                                       Slewing bearing (turntable bearing) Selection calculation method: Static reference load Fa 'and M' calculation method Single row four point contact ball Single-row four-point contact ball slewin...                                        Slewing bearing (turntable bearing) Selection calculation method: Static reference load Fa 'and M' calculation method Single row four point contact ball Single-row four-point contact ball slewing bearing selection calculation according to the bearing angle of 45 ° and 60 ° two cases. I, a = 45 ° Ⅱ, a = 60 ° Fa '= (1.225 • Fa + 2.676 • Fr) • fs Fa' = (Fa + 5.046 • Fr) • fs M '= 1.225 • M • fs M' = M • fS Then find the above two points on the graph, one of which can be below the curve. Single row crossed roller type Fa '= (Fa + 2.05 • Fr) • fs M '= M • fs Double row different diameter ball For double-row reduced-diameter ball slewing bearing selection calculation, Fr ≤ 10% Fa, Fr negligible. When Fr> 10% Fa, we must take into account changes in the pressure angle of the raceway, the calculation, please contact us. Fa '= Fa • fs M '= M • fs Three-row roller When selecting three-row roller slewing bearing, only the effect of axial roller load and overturning moment is calculated. Fa '= Fa • fs M '= M • fs On January 1, 2008, the National Development and Reform Commission promulgated a new standard of slewing bearing with the participation of our company. 1. By JB / T 10837-2008 "construction machinery and equipment three rows of column slewing bearings" instead of JG / T 68-1999 "three rows of columnar construction machinery slewing ring"; 2. By JB / T 10838-2008 "Construction machinery and equipment single row cross roller (cone) slewing bearing" instead of JG / T 67-1999 "single row crossed roller bearings (construction machinery)", the new standard to cancel the original Appendix 1 "Supplement Series of specifications "; 3. By JB / T 10839-2008" construction machinery and equipment single volleyball slewing ring "instead of JG / T 66-1999" single row ball slewing ring for construction machinery ", the new standard to increase the overlap section configuration, Cancel some of the less common specifications, the new part of the specification, increased to 48; to cancel the original Appendix A "Supplementary Series Specifications"; performance curve by d0 ≤ 40,57 HRC, d0 ≥ 50,55 HRC drawing. Three new standards have abolished product quality grading, since July 1, 2008 onwards. View Details
The relationship between industrial robot accuracy and bearing design
                                       For industrial robots, accuracy is a very important factor that directly affects product quality and productivity. The main factor affecting the accuracy of industrial robots is the bearings. So what kind of bea...                                        For industrial robots, accuracy is a very important factor that directly affects product quality and productivity. The main factor affecting the accuracy of industrial robots is the bearings. So what kind of bearings can make industrial robots have higher precision? 1. Design of key structural parameters Industrial robot bearings have the requirements of long life, high rigidity and low friction. Therefore, when designing industrial robots, not only the maximum rated dynamic load should be considered, but also the optimal value of each structural parameter should be carefully selected to improve the contact stress distribution of the bearing parts. Then it can reach the optimum contact state for the formation of the lubricating oil film and improve the service life of the bearing. 2. The raceway position The inner and outer rings of the contact ball bearing of the industrial robot adopt the integral structure, and the general sectional area is only 20% of the bearing with the same inner diameter standard, so the radial wall thickness of the cage is very limited. If the position is designed in the middle of bearing width, the bearing becomes a symmetrical structure and the strength of the bottom of the cage and the mounting position of the sealing ring will be limited. Therefore, in order to ensure that the bearing cage has sufficient strength and the sealing ring has sufficient installation space, the groove position adopts an asymmetrical design on both end faces. 3.The height of the flange When the contact ball bearing of an industrial robot is in working condition, it must bear a certain axial load while receiving a certain radial load. If the axial load is too large, it may cause the break of contact ellipse between the steel ball and the edge of the inner and outer rings or between the flange and the raceway. And then, stress concentration will occur and the bearing ring will be worn, which will affect accuracy. Therefore, when the flange height is designed, the minimum flange height J of the bearing ring is calculated according to the Hertz contact stress theory according to the axial load of the bearing, and the diameter of the ring flange is calculated. In the design, the contact ball bearing cross-sectional area is considered small, and the flange height coefficient can be smaller than the deep groove ball bearing under the premise of satisfying the use requirement. 4.Sealing structure design If the sealing property is not good, the impurities or other contaminants in the air will easily enter the bearing, thereby gradually failing the grease and resulting in bearing damage. Therefore, the sealing of the bearing is critical. When designing sealed bearing, it is necessary to consider the sealing and the specific working requirements of the bearing and the specific structural form of the bearing. Industrial robots are moving toward miniaturization, light weight, and precision. Therefore, the lubrication of bearings for industrial robots is preferably greased by means of a lubrication method with a sealing structure. 5.The characteristics of industrial robot bearing There are two ways to match the inner ring of the bearing and the sealing lip: Contact seal with inner ring seal lip in contact with inner ring rib Non-contact seal with inner ring seal lip in contact with inner ring rib 6.ZYS can offer the complete solution for industrial robot bearing. Any demand, please send email to zysdong@gmail.com. View Details