There are raceways on the inner and outer rings of angular contact ball bearings, and the inner and outer rings can make relative displacement along the axial direction of the bearing. This kind of bearing is especially suitable for bearing composite loads, that is, radial and axial loads acting at the same time. The axial load bearing capacity of angular contact ball bearing varies with the contact angle α Increase with the increase of. The contact angle is the angle between the connecting line of the contact point between the ball and the raceway in the radial plane and the vertical line of the bearing axis.

The models of angular contact ball bearings are divided into: α= 15 ° angular contact ball bearing (70000C type); α= 25 ° angular contact ball bearing (70000ac type); α= 40 ° angular contact ball bearing (70000b type); Back to back paired double angular contact ball bearings [70000C (AC, b) / DB type]; Face to face double angular contact ball bearings [70000C (AC, b) / DF type]; Series paired double angular contact ball bearings [70000C (AC, b) / dt type]; Double row angular contact ball bearing with ball notch (00000 type); Double row angular contact ball bearing without ball notch (00000a type); Double row angular contact ball bearing (00000a-z type) without ball loading notch and with dust cover on one side; Double row angular contact ball bearing (00000a-2z type) without ball notch and with dust cover on both sides; Double row angular contact ball bearing (00000 ARS type) without ball loading notch and with sealing ring on one side; Double row angular contact ball bearing without ball notch and with sealing rings on both sides (00000a-2rs type); There are 13 kinds of four point angular contact ball bearings (qj0000 type).

Angular contact ball

Single row angular contact ball bearing

It can only bear the axial load in one direction. When it bears the radial load, it will cause additional axial force. And can only limit the axial displacement of the shaft or housing in one direction. The contact angle of angular contact ball bearing is 40 degrees, so it can bear a large axial load. Angular contact ball bearing is a non separable design, and the shoulders on both sides of the inner and outer rings are different. In order to improve the load capacity of the bearing, the shoulder on one side will be machined lower, so that the bearing can be loaded with more steel balls.

Double row angular contact ball bearing

It can bear the combined radial and axial load and torque load dominated by large radial load, and limit the axial displacement of the shaft in two aspects. In the components mainly used to limit the two-way axial displacement of the shaft and housing, the tilting ability between the inner and outer rings of the double row angular contact ball bearing is limited. The allowable tilting angle depends on the internal clearance, bearing size, internal design and the force and torque acting on the bearing, and the maximum allowable tilting angle shall ensure that excessive additional stress will not be generated in the bearing. If there is an inclination angle between the inner and outer rings of the bearing, it will affect the service life of the bearing, reduce the operation accuracy of the bearing and increase the operation noise. Double row angular contact ball bearings generally use nylon cage or brass solid cage. When installing the 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 loading gap on one side, it should be noted that the main axial load should not pass through the groove edge on the notched side. When using the bearing, pay attention to make the raceway on one side without ball loading notch bear the main load.

Paired double ball bearing

If it is installed in pairs, make the outer rings of a pair of bearings opposite, that is, the wide end face to the wide end face, and the narrow end face to the narrow end face. In this way, additional axial force can be avoided, and the shaft or housing can be limited to the axial clearance in both directions.

Because the raceway of its inner and outer rings can have relative displacement on the horizontal axis, it can bear both radial load and axial load - combined load (single row angular contact ball bearing can only bear single direction axial load, so it is usually installed in pairs).

The cage is made of brass, synthetic resin, etc., which can be distinguished according to the bearing form and service conditions.

Angular contact ball bearings are mostly manufactured by foreign bearing manufacturers, and are mostly used in imported equipment in China, such as angular contact ball bearings 3204rs, etc,

The narrow side is outside, the wide side is inside, the other wide side is inside, and the narrow side is outside, which is back-to-back contact.

characteristic

1. Universal matched bearing

Universal matched bearings are specially processed. When the bearings are installed close to each other, any combination can achieve the established internal clearance or preload and average load distribution without using gaskets or similar devices.

Paired bearings are used when the load carrying capacity of a single bearing is insufficient (using the channeling configuration) or when it is to bear the combined load or the axial load acting in two directions (using the back-to-back or face-to-face configuration).

2. Bearings of basic design (cannot be used as general matching group) are used for the configuration of individual bearings

The basic design of single row angular contact ball bearings is mainly used in the configuration of only one bearing in each position. Its width and protrusion are ordinary tolerances. Therefore, it is not suitable to install two single row angular contact ball bearings close to each other.

3. The accuracy grade of angular contact ball bearing includes dimensional tolerance and rotation accuracy. The accuracy from low to high is expressed as P0 (normal), P6 (p6x), P5, P4 and P2. In addition, P9 and P3 are equivalent to ISO standards, and P7 and P3 are also equivalent to JIS standards.

Angular contact ball bearings include:

7000c (∝ = 15 °), 7000ac (∝ = 25 °) and 7000b (∝ = 40 °). The locking port of this kind of bearing is on the outer ring. Generally, the inner and outer rings cannot be separated, and can bear the combined radial and axial load and the axial load in one direction. The ability to bear axial load is determined by the contact angle. The larger the contact angle, the higher the ability to bear axial load. The bearing can limit the axial displacement of the shaft or housing in one direction.

The ultimate speed of contact ball bearing is high, which can bear both radial load and axial load, and can also bear pure axial load. Its axial load capacity is determined by the contact angle and increases with the increase of contact angle.

Single row angular contact ball bearing

Single row angular contact ball bearings can only bear axial load in one direction. When bearing radial load, additional axial force will be caused, and the corresponding reverse load must be applied. Therefore, this kind of bearings are generally used in pairs. Double row angular contact ball bearing can bear large radial and axial two-way combined load and moment load dominated by radial load. It can limit the two-way axial displacement of shaft or shell, and the contact angle is 30 degrees.

Bearing code: 7

Install angular contact ball bearings in pairs

Angular contact ball bearings installed in pairs can withstand radial and axial combined loads dominated by radial loads, as well as pure radial loads. The series configuration can only bear the axial load in a single direction, while the other two configurations can bear the axial load in either direction. This type of bearing is generally selected and combined by the manufacturer and submitted to the user in pairs. After installation, there is preloading interference, and the ferrule and steel ball are in the axial preload state, which improves the stiffness and rotation accuracy of the whole group of bearings as a single support.

Back to back configuration,

The rear code is dB (such as 70000 / DB), and the load line of the back-to-back paired bearing is separated from the bearing shaft. It can bear the axial load acting in two directions, but the load in each direction can only be borne by one bearing. Back to back mounted bearings provide a relatively rigid bearing configuration and can withstand overturning torque.

Face to face configuration,

The rear code is DF (such as 70000 / DF), and the load line of the face-to-face matched bearing meets the bearing shaft. It can bear the axial load acting in two directions, but the load in each direction can only be borne by one bearing. This configuration is not as rigid as back-to-back pairing, and is not suitable for bearing overturning moment. The rigidity and ability to bear overturning moment of this configuration are not as good as that of DB configuration, and the bearing can bear bidirectional axial load;

Series configuration,

The rear code is DT (such as 70000 / DT). When in series configuration, the load line is parallel, and the radial and axial loads are evenly shared by the bearing. However, the bearing group can only bear the axial load acting in one direction. If the axial load acts in the opposite direction, or if there is a composite load, a third bearing adjusted relative to the series paired bearing must be added. This configuration can also connect three or more bearings in series at the same support, but it can only bear the axial load in one direction. Generally, in order to balance and limit the axial displacement of the shaft, a bearing that can bear the axial load in the other direction needs to be installed at the other support.

Bearing code: 0

Load capacity (Simplified)

The following is only for the load capacity of the mating bearing, and the basic rated load and fatigue limit load given in the product table are only applicable to a single bearing.

*Basic dynamic load rating for standard bearings in any configuration and jXN bearings in back-to-back or face-to-face configuration

C = 1, 62xc single bearing

*Basic dynamic load rating for SKF Explorer bearings in series configuration

C = 2XC single bearing

*Basic rated static load

Co = 2xco single bearing

*Fatigue limit load

Pu = 2xpu single bearing

Types of structural deformation

The characteristic of double row angular contact ball bearing is that it can bear the combined load of radial and axial load at the same time, and limit the axial displacement of the shaft. Compared with the two-way thrust ball bearing, this bearing has higher limit speed, 32 degree contact angle, good rigidity and large overturning torque. It is widely used in the front wheel hub of cars (some models also use double row tapered roller bearings of the same size).

There are four structural deformations of double row angular contact ball bearings:

Type A: Standard Design of bearings with outer diameter less than or equal to 90mm. No ball loading notch, so it can bear equal two-way axial load. Light glass fiber reinforced nylon 66 cage is adopted, and the temperature rise of the bearing is very small.

Type A: Standard Design of bearings with outer diameter greater than 90mm. There is a ball loading notch on one side, which is equipped with Z steel plate stamping cage or brass solid cage.

Type E: it is a reinforced structure with a ball loading notch on one side, which can load more steel balls, so the bearing capacity is high.

Double row angular contact ball bearings with dust cover on both sides and seal ring on both sides. Double row angular contact ball bearings with A-type design and E-type design can be provided with dust cover (non-contact type) or seal ring (contact type) on both sides. The interior of the sealed bearing is filled with antirust lithium grease, and the operating temperature is generally between - 30 ℃ and 110 ℃. No re lubrication is required during use and no heating is required before installation.

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 loading gap on one side, it should be noted that the main axial load should not pass through the groove edge on the notched side.

Main purpose:

Single row angular contact ball bearings: machine tool spindle, high-frequency motor, gas turbine, centrifugal separator, small car front wheel, differential pinion shaft, booster pump, drilling platform, food machinery, dividing head, repair welding machine, low-noise cooling tower, electromechanical equipment, coating equipment, machine bed slot plate and arc welding machine

Double row angular contact ball bearings: oil pump, roots blower, air compressor, various transmissions, fuel injection pump, printing machinery, planetary reducer, extraction equipment, cycloidal reducer, food packaging machinery, electric welding machine, electric soldering iron, square box, gravity spray gun, wire stripper, half shaft, inspection and analysis equipment, fine chemical machinery

High speed precision angular contact ball bearing is mainly used in high-speed rotating occasions with light load. It requires high precision, high speed, low temperature rise, low vibration and certain service life. It is often used as the support of high-speed motorized spindle. It is the key kit of high-speed motorized spindle of internal surface grinder.

Installation form

The automatic selection of angular contact ball bearings can be provided. The installation forms of angular contact ball bearings include back-to-back, face-to-face and series arrangement. When the two bearings are installed back-to-back (the wide end faces of the two bearings are opposite), the contact angle line of the bearing diffuses along the direction of the rotation axis, which can increase the rigidity of its radial and axial support angles, and has the maximum deformation resistance; When installed face-to-face (the narrow end faces of the two bearings are opposite), the contact angle line of the bearing converges towards the rotation axis, and its bearing angle rigidity 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; When installed in series arrangement (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 can share the working load in the same direction. However, when using this installation form, in order to ensure the axial stability of installation, two pairs of bearings arranged in series must be installed opposite at both ends of the shaft.

Main technical indicators:

1. Bearing accuracy index: exceeding grade P4 accuracy in GB / 307.1-94

2. High speed performance index: DMN value 1.3 ~ 1.8x 106 / min

3. Service life (average): > 1500 H

The service life of high-speed precision angular contact ball bearing is closely related to the installation. The following matters should be paid attention to

1. The bearing shall be installed in a dust-free and clean room. The bearing shall be carefully selected and matched. The spacer for the bearing shall be ground. On the premise of maintaining the equal height of the inner and outer spacer, the parallelism of the spacer shall be controlled below 1um;

2. The bearing shall be cleaned before installation. During cleaning, the inner ring slope shall be upward, and the hand sensing shall be flexible without stagnation. After drying, the specified amount of grease shall be put in. In case of oil mist lubrication, a small amount of oil mist oil shall be put in;

3. Special tools shall be used for bearing installation, with uniform stress and no knocking;

4. The bearing shall be stored in a clean and ventilated manner without corrosive gas, and the relative humidity shall not exceed 65%. For long-term storage, it shall be regularly rustproof.

Suffix letter meaning:

B: Modified internal structure

MP: machined window brass cage

TVP: glass fiber reinforced nylon cage

UA: general structural design of bearings installed in pairs, small axial clearance bearing group

Uo: general structural design of bearings installed in pairs, zero axial clearance bearing set

Da: double half inner ring (double row angular contact ball bearing)

TVH: glass fiber reinforced polyamide cage, steel ball guide

Maintenance:

1. When the bearing runs to a certain period (or maintenance period), remove all the bearings;

2. Soak and clean the bearing with diesel oil or kerosene for cleaning. If there are technical conditions, it is best to open the sealing cover for cleaning;

3. Dry the cleaning oil after cleaning, and check the appearance for damage;

4. Use a wooden rod (preferably a hollow tube) with a diameter of about 150mm and an equal inner diameter of the angular contact ball bearing, and fix a bearing at one end;

5. While rapidly rotating the bearing by hand, push the other end of the wooden rod (wooden tube) against the ear or the microphone of the audio amplifier to listen to the rotation noise of the bearing;

6. After fixing the bearing, move the wooden rod horizontally to check whether the bearing is worn and loose;

7. JXN bearings with serious looseness, excessive rotating noise and serious defects shall be eliminated and replaced with the same model;

8. Take a bucket, melt an appropriate amount of grease (high-quality yellow dry oil) with slow fire (do not overheat), and soak the tested bearing in the bucket until there is no bubble overflow. Take out the bearing before the grease cools, and the amount of residual grease is small. After the grease is cooled, take out the angular contact ball bearing, and there is a large amount of residual grease. Determine the amount of grease residue as needed.