双列角接触球轴承的设计基本上与单列角接触球轴承相同，但只占用更小的轴向

The design of double-row angular contact ball bearings is basically the same as that of single-row angular contact ball bearings, but it only takes up less axial space. Double-row angular contact ball bearings can bear radial loads and axial loads acting in two directions. It can limit the axial displacement of the shaft or the housing in two directions. The contact angle is 30 degrees. Can provide high rigidity bearing configuration, and can withstand overturning moment. <br><br>Design Features <br>Double-row angular contact ball bearings can withstand large radial loads, mainly radial and axial combined loads and moment loads, limiting axial displacement in both sides of the shaft. Mainly used in components that limit the axial displacement of the shaft and the housing in both directions. <br>For example: SKF double row angular contact ball bearings are similar in design to two single row contact ball bearings arranged back to back, but the width is slightly narrower than the two single row bearings. Compared with single-row bearings, it has better rigidity [1]. <br><br>Structural classification <br>(1) Standard design of A-type bearings with an outer diameter less than or equal to 90mm. There is no ball gap, so it can bear equal bidirectional axial load. The use of lightweight glass fiber reinforced nylon 66 cage, the bearing temperature rise is very small. <br>(2) Standard design for B-type bearings with an outer diameter greater than 90mm. There is a ball loading notch on one side, equipped with steel stamping cage or brass solid cage. <br>(3) Type C is a reinforced structure, with a ball loading notch on one side, which can hold more steel balls, so the load carrying capacity is higher. <br>(4) Double-row angular contact ball bearings with dust cover on both sides and seal ring on both sides, A-type design and C-type design can be equipped with dust cover (non-contact) or sealing ring (contact type) on both sides ). Sealed bearings are filled with anti-rust lithium-based grease, the operating temperature is generally -30 ~ +110 ℃. No relubrication is required during use, and it should not be heated or cleaned before installation. <br><br>Range of applications <br>as compared with the single row angular contact ball bearings, double row angular contact ball bearing having better rigidity and can withstand the overturning moment. The bearings are non-detachable. Especially suitable for applications with high rigidity requirements. Widely used in the front wheel hubs of cars (some models also use double-row tapered roller bearings of the same size) [2]. <br><br>Performance characteristics<br>The tiltability between the inner and outer rings of double row angular contact ball bearings is limited. The allowable tilt angle depends on the internal clearance of the bearing, the bearing size, the internal design, and the forces and moments acting on the bearing. The maximum allowable tilt angle should be guaranteed There will be no excessively high additional stress in the bearing. <br>If there is an inclination angle between the inner and outer rings of the bearing, it will affect the life of the bearing, and at the same time cause the bearing's running accuracy to decrease and the running noise to increase. Double row angular contact ball bearings generally use nylon cage or brass solid cage. When installing double-row angular contact ball bearings, it should be noted that although the bearings can withstand two-way axial loads, if there is a ball loading gap on one side, care should be taken not to let the main axial load pass through the groove side of the gap. When using bearings, care should be taken to make the one side raceway without the ball notch bear the main load. <br><br>Double-row angular contact ball bearing installation method The installation of <br><br>double-row angular contact ball bearings is more complicated than deep groove ball bearings, mostly in pairs, and Pre-loading is required. Good installation can greatly improve the working accuracy and bearing life of the host; otherwise, not only the accuracy can not meet the requirements, but also the life will be affected. ? <br>There are three types of double-row angular contact ball bearing installation: back-to-back, face-to-face and tandem arrangement. So what are the characteristics and benefits of each of these three installation forms? ? <br>-Back (wide face two opposite bearing) is mounted, the bearing contact angle lines in the pivot axis direction of the diffuser, which can increase the angle of radial and axial bearing rigidity, the maximum resistance to deformation;? <br>Face (bearing two narrow end During relative installation, the contact angle of the bearing converges towards the axis of rotation, and its ground bearing angle is less rigid. Since the bearing outer ring inner ring projecting, when the outer ring bearing two pressing together, eliminate the original clearance of the outer ring can be increased preload bearing;? <br>Are arranged in series (in a width direction of the two end faces of the bearing) mounted At this time, the contact angle lines of the bearings are in the same direction and parallel, so that the two bearings can share the working load in the same direction. However, when using this type of installation, in order to ensure the axial stability of the installation, two pairs of bearings arranged in series must be installed opposite the two ends of the shaft. ?<br>In addition, pay attention to a parameter during the installation process to obtain the preload. The preload can be achieved by grinding the end face of a ring in the bearing, or using two spacers of different thickness between the inner and outer rings of a pair of bearings to clamp the bearings together so that the steel ball and the raceway Obtained in close contact. ? <br>Large size preload effect on bearing life, according to the information, when the bearing is equipped with a 0.012mm interference, reduced service life 380, 0.016mm when there is interference, reducing the service life 501; when the bearing When equipped with a 0.004mm gap, the service life is significantly reduced, and with a 0.008mm gap, the service life is reduced by 705. ? <br>Therefore, it is very important to choose the size of the preload. Generally, a small preload should be used for high speed, and a large preload should be used for low speed. At the same time, the preload should be slightly greater than or equal to the axial working load. ? After the <br>double-row angular contact ball bearings pass the assembly inspection, they should be run at the working speed for a dry run test, the time is not less than 2h, and the temperature rise should not exceed 15 ℃

The design of a two-column angle contact ball bearing is essentially the same as a single-angle contact ball bearing, but only takes up a smaller axial space. Two-row angle contact ball bearings can withstand radial loads and axial loads acting in both directions, limiting the axial displacement of the shaft or housing in both directions at a contact angle of 30 degrees. It can provide a highly rigid bearing configuration and can withstand the moment of rollover.<br><br>Design features<br>Two-column angle contact ball bearings can withstand large radial and axial combined and torque loads, limiting the axial displacement of both sides of the shaft. It is primarily used to limit the two-way axial displacement of the shaft and housing in the part.<br>For example, SKF two-column angle contact ball bearings are designed to be similar to two back-to-back single-row contact ball bearings, but slightly narrower in width than two single-row bearings. Better rigidity than a single-row bearing.<br><br>Structural classification<br>(1) The standard design of type A bearings with an outer diameter of less than or equal to 90mm. No loading gap, so it can withstand equal bidirectional axial loads. Using light fiberglass reinforced nylon 66 cage, bearing temperature rise is very small.<br>(2) Standard design for type B bearings with a diameter greater than 90mm. There is a ball-loading gap on one side, equipped with a steel plate punch cage or brass body cage.<br>(3) C-type is a reinforced structure, one side with a ball gap, can be installed more steel balls, so the carrying capacity is higher.<br>(4) Two-sided contact ball bearings with dust-proof cover type and two-sided seal type A-type design and C-type design can be both sides with dust cover (non-contact) or seal ring (contact type). The interior of the sealed bearings is filled with rust-proof lithium-based grease, and the operating temperature is generally between -30 and 110 degrees C. No relubrication during use, should not be heated before installation, and should not be cleaned.<br><br>Scope of application<br>Compared with single-row angle contact ball bearings, double-row angle contact ball bearings have better rigidity and can withstand the moment of roll-over. The bearings are non-separated. Ideal for applications with high rigidity requirements. Widely used in the front wheels of small cars (some models also use the same size of two-row conical roller bearings) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .<br><br>Performance features<br>The slope ability between the inner and outer rings of the two-row angle contact ball bearing is limited, allowing the tilt angle to depend on the internal clearance of the bearing, bearing size, internal design and the force and torque acting on the bearing, and the maximum allowable tilt angle should ensure that there is no excessive additional stress in the bearing.<br>If there is a tilt angle between the inner and outer rings of the bearing, it will affect the life of the bearing, and at the same time cause the bearing operating accuracy to decrease, the operating noise increases. Double-column angle contact ball bearings are generally made of nylon cageor or brass body cage. Two-row angle contact ball bearing installation should be noted that, although the bearing can withstand two-way axial load, but if there is a ball filling gap on one side, it should be noted that the main axial load through the gaped side of the ditch. Attention should be paid to the main load on one side raceway without a ball notch when using bearings<br><br>Two-column angle contact ball bearing installation method<br><br>The installation of double-column angle contact ball bearings is more complex than deep trench ball bearings, mostly in pairs, and pre-loaded. Well installed, can make the operating accuracy of the host, bearing life greatly improved;<br>There are three forms of installation of double-row angle contact ball bearings, namely: back-to-back, face-to-face and series arrangement of three. So what are the characteristics and benefits of each of these three forms of installation?<br>When rear-to-back (the wide end face of the two bearings is relative) installed, the contact angle of the bearing diffuses along the direction of the swing axis, which can increase its radial and axial support angle rigidity, with maximum resistance to deformation;?<br>When installed face-to-face (the narrow end face of the two bearings opposite), the contact angle of the bearing converges in the direction of the swing axis, and its ground bearing angle is less rigid. Due to the inner ring of the bearing protruding the outer ring, when the outer ring of the two bearings is pressed together, the original gap of the outer ring is eliminated, which can increase the pre-load of the bearing;?<br>When arranged in series (the wide end face of the two bearings in one direction) is installed, the contact angle of the bearings is parallel and parallel, allowing the two bearings to share the working load in the same direction. However, when using this mounting form, in order to ensure the axial stability of the installation, two pairs of bearings arranged in series must be installed diagonally at both ends of the shaft.<br>In addition, in the installation process should pay attention to a parameter, pre-load acquisition. Pre-load can be obtained by repairing the end face of a collar in the bearing, or by placing two different thickness compartments between the inner and outer rings of a pair of bearings, and clamping the bearings together so that the steel ball is in close contact with the raceway.<br>The size of the preload has a great impact on the life of the bearing, according to the relevant information, when the bearing assembly has 0.012mm over-earnings, the service life is reduced by 380, there is 0.016mm over-earnings, the service life is reduced by 501;<br>Therefore, it is very important to make a reasonable choice of the size of the preloaded load. Generally high speed should choose small pre-load, low speed should choose a large pre-load. At the same time, the pre-load should be slightly greater than or equal to the axial operating load.<br>After the double-column angle contact ball bearing sits through the assembly inspection, the operating speed shall be used for empty operation test, the time is not less than 2h, the temperature rise shall not exceed 15 degrees C

The design of double row angular contact ball bearing is basically the same as that of single row angular contact ball bearing, but it only takes up less axial space. Double row angular contact ball bearing can bear radial load and axial load acting in two directions. It can limit axial displacement of shaft or shell in two directions, and the contact angle is 30 degrees. It can provide high rigidity bearing configuration and can withstand overturning moment.<br>Design features<br>The double row angular contact ball bearing can bear the combined radial and axial load and moment load which are mainly radial load, and limit the axial displacement of the two sides of the shaft. It is mainly used in the parts that limit the two-way axial displacement of the shaft and the shell.<br>For example, SKF double row angular contact ball bearing is similar to two back-to-back single row contact ball bearings in design, but its width is slightly narrower than two single row bearings. It has better rigidity than single row bearing [1].<br>Structure classification<br>(1) Standard design for type a bearings with OD less than or equal to 90mm. There is no loading gap, so it can bear equal bi-directional axial load. Using light glass fiber reinforced nylon 66 cage, the temperature rise of bearing is very small.<br>(2) Standard design for bearings with an outside diameter greater than 90mm. There is a ball loading gap on one side, equipped with a steel plate stamping cage or a brass solid cage.<br>(3) Type C is a reinforced structure with a ball loading gap on one side, which can hold more steel balls, so it has a high bearing capacity.<br>(4) Double row angular contact ball bearings with dust cover on both sides and seal ring on both sides can have dust cover (non-contact type) or seal ring (contact type) on both sides. The inside of sealed bearing is filled with anti rust lithium base grease, and the operating temperature is generally - 30 ～ + 110 ℃. During use, it is not necessary to re lubricate, and it shall not be heated or cleaned before installation.<br>Application scope<br>Compared with single row angular contact ball bearing, double row angular contact ball bearing has better rigidity and can bear overturning moment. The bearing is non separating type. It is especially suitable for applications with high rigidity requirements. It is widely used in the front wheel hub of cars (some models also use double row tapered roller bearings of the same size) [2].<br>Performance characteristics<br>The tilting between the inner and outer rings of double row angular contact ball bearings is limited. The allowable tilting angle depends on the internal clearance, bearing size, internal design and the force and moment acting on the bearing. The maximum allowable tilting angle shall ensure that no excessive additional stress will be generated in the bearing.<br>If there is an inclination angle between the inner and outer rings of the bearing, the service life of the bearing will be affected, and the running accuracy of the bearing will be reduced and the running noise will be increased. Generally, double row angular contact ball bearing adopts nylon cage or brass solid cage. During the installation of double row angular contact ball bearing, it should be noted that although the bearing can bear two-way axial load, if there is a ball mounting gap on one side, it should be noted that the main axial load should not pass through the groove edge of the notched side. When using the bearing, pay attention to make the side raceway without ball loading notch bear the main load<br>Installation method of double row angular contact ball bearing<br>The installation of double row angular contact ball bearing is more complex than that of deep groove ball bearing, which is usually installed in pairs and requires preloading. Good installation can greatly improve the working accuracy and bearing life of the main engine; otherwise, not only the accuracy fails to meet the requirements, but also the life will be affected. ?<br>There are three kinds of installation forms of double row angular contact ball bearings: back-to-back, face-to-face and series arrangement. So what are the characteristics and benefits of each of these three types of installation? ?<br>When the back-to-back (the wide end faces of the two bearings are opposite) is installed, the contact angle line of the bearing spreads along the direction of the rotation axis, which can increase the rigidity of the radial and axial bearing angles, and the maximum deformation resistance;?<br>When face-to-face (the narrow end faces of two bearings are opposite), the contact angle line of the bearing converges towards the rotation axis direction, and the rigidity of the bearing angle is small. Since the inner ring of the bearing extends out of the outer ring, when the outer rings of the two bearings are pressed together, the original clearance of the outer ring is eliminated, which can increase the preload of the bearing;?<br>When the two bearings are installed in series (the wide end faces of the two bearings are in one direction), the contact angle lines of the bearings are in the same direction and parallel, so that the two bearings share the working load in the same direction. However, in order to ensure the axial stability of the installation, two pairs of bearings arranged in series must be installed at both ends of the shaft. ?<br>In addition, in the process of installation, pay attention to a parameter, the acquisition of preload. The preload can be obtained by grinding the end face of a ferrule in the bearing, or by placing two spacer rings of different thickness between the inner and outer rings of a pair of bearings to clamp the bearings together so that the steel ball and the raceway are in close contact. ?<br>The preload has a great influence on the service life of the bearing. According to relevant data, when the bearing is equipped with 0.012mm interference, the service life will be reduced by 380, when there is 0.016mm interference, the service life will be reduced by 501; when the bearing is equipped with 0.004mm clearance, the service life will be significantly reduced, when there is 0.008mm clearance, the service life will be reduced by 705. ?<br>Therefore, it is very important to choose the appropriate preload. Generally, small preload should be selected for high speed and large preload should be selected for low speed. At the same time, the preload shall be slightly greater than or equal to the axial working load. ?<br>After the double row angular contact ball bearing passes the assembly inspection, it is required to conduct the no-load running test at the working speed for at least 2h, and the temperature rise shall not exceed 15 ℃<br>