Bearings are important components in mechanical equipment. Its main function is to support the mechanical rotating body to reduce the friction coefficient of the mechanical load during the transmission process of the equipment.
What are the characteristics, differences and uses of the fourteen types of bearings in motors
Date：2023-10-12 Author：XINDA MOTOR
Bearings are divided into radial bearings and thrust bearings according to different load-carrying directions or nominal contact angles.
According to the type of rolling elements, they are divided into: ball bearings and roller bearings.
According to whether they can be aligned, they are divided into: self-aligning bearings and non-aligning bearings (rigid bearings).
According to the number of rows of rolling elements, they are divided into: single-row bearings, double-row bearings, and multi-row bearings.
According to whether the components can be separated, they are divided into: separable bearings and non-separable bearings.
There are also classifications based on structural shape and size.
This article mainly shares the characteristics, differences and corresponding uses of 14 common bearings.
Angular contact ball bearings
There is a contact angle between the ferrule and the ball. The standard contact angles are 15°, 30° and 40°. The larger the contact angle, the greater the axial load capacity. The smaller the contact angle, the more conducive to high-speed rotation. Single-row bearings can Bear radial load and unidirectional axial load. Structurally, two single-row angular contact ball bearings combined on the back share the inner ring and outer ring and can bear radial load and bidirectional axial load.
The main uses of angular contact ball bearings :
Single row: machine tool spindle, high-frequency motor, gas turbine, centrifugal separator, small car front wheel, differential pinion shaft.
Double row: oil pumps, Roots blowers, air compressors, various transmissions, fuel injection pumps, printing machinery.
Aligning ball bearings
Double rows of steel balls, the outer ring raceway is an inner spherical type, so it can automatically adjust the shaft center misalignment caused by deflection or non-concentricity of the shaft or housing. The tapered bore bearing can be easily installed on the shaft by using fasteners. Mainly Bear radial load.
Aligning ball bearings
Main uses: woodworking machinery, textile machinery drive shafts, vertical seated self-aligning bearings.
Spherical roller bearing
This type of bearing is equipped with spherical rollers between the spherical raceway outer ring and the double raceway inner ring. According to the different internal structures, it is divided into four types: R, RH, RHA and SR. Since the arc center of the outer ring raceway is The bearing center is consistent and has self-aligning performance, so it can automatically adjust the shaft center misalignment caused by deflection or non-concentricity of the shaft or housing, and can withstand radial loads and bidirectional axial loads.
Main uses of spherical roller bearings :
Papermaking machinery, reduction gears, railway vehicle axles, rolling mill gearbox seats, rolling mill rollers, crushers, vibrating screens, printing machinery, woodworking machinery, various industrial reducers, vertical seated spherical bearings.
Thrust spherical roller bearing
The spherical rollers in this type of bearing are arranged obliquely. Since the raceway surface of the seat ring is spherical and has self-aligning properties, it can allow the shaft to tilt to some extent. The axial load capacity is very large. It can withstand several axial loads at the same time. Radial load, oil lubrication is generally used when in use.
Main uses of thrust spherical roller bearings :
Hydraulic generators, vertical electric motors, propeller shafts for ships, reducers for rolling screws in rolling mills, tower cranes, coal mills, extruders, and forming machines.
Tapered Roller Bearings
This type of bearing is equipped with truncated cone-shaped rollers. The rollers are guided by the large ribs of the inner ring. They are designed so that the apexes of the conical surfaces of the inner ring raceway surface, outer ring raceway surface and roller rolling surface intersect at the center line of the bearing. On point. Single-row bearings can bear radial loads and one-way axial loads, while double-row bearings can bear radial loads and two-way axial loads, and are suitable for bearing heavy loads and impact loads.
Main uses of tapered roller bearings :
Automobile: front wheels, rear wheels, transmission, differential pinion shaft. Machine tool spindles, construction machinery, large agricultural machinery, railway vehicle gear reduction devices, rolling mill roll necks and reduction devices.
Deep groove ball bearing
Structurally, each ring of a deep groove ball bearing has a continuous groove raceway with a cross-section approximately one-third of the equatorial circumference of the ball. Deep groove ball bearings are mainly used to bear radial loads and can also bear certain axial loads.
When the radial clearance of the bearing increases, it has the properties of an angular contact ball bearing and can withstand alternating axial loads in two directions. Compared with other types of bearings of the same size, this type of bearing has a small friction coefficient, a high limit speed, and high precision. It is the preferred bearing type for users when selecting.
Main uses of deep groove ball bearings :
Automobiles, tractors, machine tools, motors, water pumps, agricultural machinery, textile machinery, etc.
Thrust ball bearing
It consists of a washer-shaped raceway ring with a raceway and a ball and cage assembly. The raceway ring that matches the shaft is called a shaft ring, and the raceway ring that matches the shell is called a seat ring. The two-way bearing matches the secret shaft of the middle ring. The one-way bearing can bear one-way axial load, and the two-way bearing can bear two-way axial load (neither can bear radial load).
The main uses of thrust ball bearings are: automobile steering pins and machine tool spindles.
Thrust roller bearing
Thrust roller bearings are used for shafts that bear mainly axial load and combined meridional load, but the meridional load shall not exceed 55% of the axial load. Compared with other thrust roller bearings, this kind of bearing has a lower friction coefficient, higher rotation speed, and has the ability to adjust. The rollers of the 29000 bearing are asymmetric spherical rollers, which can reduce the relative sliding between the stick and the raceway during operation. The rollers are long and have a large diameter. They have a large number of rollers and a large load capacity. They are usually lubricated with oil. Some bearings are lubricated with oil. Grease lubrication can be used at low speeds.
The main uses of thrust roller bearings are: hydraulic generators, crane hooks.
Cylindrical Roller Bearings
The rollers of cylindrical roller bearings are usually guided by two ribs of a bearing ring. The cage roller and guide ring form an assembly that can be separated from another bearing ring and are separable bearings.
This kind of bearing is more convenient to install and disassemble, especially when the interference fit between the inner and outer rings, the shaft and the shell is required. This type of bearing is generally only used to bear radial loads. Only single-row bearings with ribs on both the inner and outer rings can bear small steady axial loads or large intermittent axial loads.
The main uses of cylindrical roller bearings are: large motors, machine tool spindles, axle boxes, diesel engine crankshafts, automobiles, gearboxes with bearings, etc.
Four point contact ball bearings
It can bear radial load and bidirectional axial load. A single bearing can replace the angular contact ball bearing of front combination or back combination. It is suitable for bearing pure axial load or synthetic load with large axial load component. This type of bearing can withstand any direction. One of the contact angles can be formed when there is an axial load, so the ferrule and the ball are always in contact with three points on both sides of any contact line.
The main uses of four-point contact ball bearings are: aircraft jet engines and gas turbines.
Thrust cylindrical roller bearings
It consists of a washer-shaped raceway ring (shaft ring, seat ring) and cylindrical roller and cage components. The cylindrical roller adopts convex surface processing, so the pressure between the roller and the raceway surface is evenly distributed, and it can withstand one-way axial load. It has large axial load capacity and strong axial rigidity.
The main uses of thrust cylindrical roller bearings are: oil drilling rigs, iron and steel making machinery.
Thrust needle roller bearing
Separable bearings are composed of raceway rings, needle rollers and cage assemblies, and can be arbitrarily combined with stamped thin raceway rings or cut-processed thick raceway rings. Non-separable bearings are integral bearings composed of precision stamped raceway rings, needle rollers and cage assemblies. They can withstand unidirectional axial loads. This type of bearing takes up little space and is conducive to the compact design of machinery. Most of them Only the needle roller and cage assembly is used, and the mounting surface of the shaft and housing is used as the raceway surface.
The main uses of thrust needle roller bearings are: transmission devices for automobiles, cultivators, machine tools, etc.
Thrust tapered roller bearings
This type of bearing is equipped with truncated cone-shaped rollers (the big end is spherical). The rollers are accurately guided by the ribs of the raceway ring (shaft ring, seat ring). The design ensures that the raceway surfaces of the shaft ring and seat ring and the rolling surface of the rollers are The apex of each conical surface intersects at a point on the bearing center line. One-way bearings can bear one-way axial load, and two-way bearings can bear two-way axial load.
Main uses of thrust tapered roller bearings :
One-way: Crane hook, oil drilling rig swivel.
Both directions: rolling mill roll neck.
Insert spherical ball bearing with seat
The seated spherical ball bearing is composed of an spherical ball bearing with seals on both sides and a cast (or steel plate stamped) bearing seat. The internal structure of the outer spherical ball bearing is the same as that of the deep groove ball bearing, but the inner ring of this bearing is wider than the outer ring. The outer ring has a spherical outer surface, which can be automatically aligned with the concave spherical surface of the bearing seat.
Main uses: mining, metallurgy, agriculture, chemical industry, textile, printing and dyeing, conveying machinery, etc.
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