The bearings are designed to support the shaft, or the part of the linear motion shaft, which plays the role of supporting the rotating body or the linear moving body in the machine.
What is Bearing?
What are Bearings? Bearings are devices used to achieve rotational or linear motion while reducing friction and handling stress. Bearings are similar to wheels in that they enable the device to roll, thereby reducing friction between the bearing surface and its rolling surface.
The Working Principle of the Bearing:
The bearings use a relatively simple construction: The balls with smooth metal surfaces inside and out to aid in rolling. The inner ring is usually a tight fit with the shaft and rotates with the shaft. The outer ring usually cooperates with the housing hole of the bearing seat or the housing of the mechanical part to play a supporting role. The rolling elements are evenly arranged with the help of the cage, which evenly separates the rolling elements and guides the rolling elements to move on the correct track. The weight of the ball itself carrying the load is the force that drives the bearing to rotate. The load rotates by applying force to the bearing in the same way, including radial load and thrust load.
Classification of Bearings:
- Radial load: The weight is placed on the bearing in the pulley so that the bearing rolls or rotates due to tension.
- Thrust load: The bearing is flipped over on its side and is subjected to full force at that angle.
- Classified according to the direction of the load that the bearing bears
- Classified according to the size of the bearing
- Classified according to the shape of the bearing rolling element
- Classified according to bearing movement mode
- Classified according to the number of rows of bearing rolling elements
- Classify according to whether the bearing parts can be separated or not
The Function of Bearings:
The main function of the bearing is to support the mechanical rotating body, reduce the friction coefficient during the movement process, and ensure rotation accuracy.
Bearings rely on the rolling contact between the components to support the transmission parts, so the sliding resistance is small, the power consumption is low, and the starting is easy. The function of the bearing is to support the mechanical rotating body, reduce the friction coefficient during its movement, and ensure its rotation accuracy. It can be understood that it is used to fix the shaft so that it can only rotate and control its axial and radial movement.
What Types of Bearing?
Different Types of Bearings and the shaft
- Rolling Bearings vs Sleeve Bearings
In a sleeve or plain bearing, the shaft and bearing move in opposite directions on the sliding surfaces. In contrast, the inner and outer ring components of rolling bearings are separated by rolling elements, which generate much less friction than sleeve bearings.
- Radial Bearings vs Axial Bearings
Bearings can transmit loads radially or axially (thrust), in many cases a combination of radial and axial loads. The choice of bearing design depends on the relevant application.
- Sliding bearing:
Bearings that work under sliding friction. Sliding bearings work smoothly, reliably, and without noise. Under the condition of liquid lubrication, the sliding surfaces are separated by the lubricating oil without direct contact, which can reduce friction loss and surface wear.
- Ball bearing:
Ball bearings are included the basic elements containing balls, inner ring, outer ring, and cage. The balls are located between the inner and outer rings, and the retainer is responsible for keeping the balls at the same distance so that the bearing can work properly.
- Deep groove ball bearing:
Deep groove ball bearings have a simple structure and are easy to use. They are the type of bearing with the largest production volume and the widest application range. It is mainly used to bear radial load, and can also bear certain axial load. When the radial clearance of the bearing increases, it has the function of an angular contact bearing and can bear a large axial load.
- Self-aligning ball bearings:
The self-aligning ball bearing has two rows, two raceways in the inner ring, and an inner spherical raceway in the outer ring, which has the effect of self-aligning. It can automatically compensate for the coaxially error caused by the bending of the shaft and the deformation of the shell and is suitable for parts where the bearing seat hole cannot guarantee strict coaxially.
- Angular contact ball bearing:
Angular contact ball bearings have a high limit speed and can bear both meridional and axial loads, as well as pure axial loads. The axial load capacity is determined by the contact angle and increases with the increase of the contact angle.
- Cylindrical roller bearing:
The rollers of cylindrical roller bearings are guided by two ribs of one bearing ring and the cage. The rollers and the guide ring form a combination, which can be separated from the other bearing ring and belong to a separable bearing. This kind of bearing is easy to install and disassemble.
Uses and Applications of Bearings:
Due to the wide range of use, the variety and complexity of bearing varieties are determined. Due to the strict requirements, the importance of bearing quality and efficiency is determined. Bearing manufacturing is a kind of precision basic parts manufacturing, its accuracy is measured by 0.001mm, while the manufacturing tolerance of ordinary mechanical parts is generally only 0.01mm.
The noise and vibration of the motor depend to a large extent on the bearing quality. The swing difference and temperature rise of the high-precision machine tool spindle are closely related to the bearing quality. The bearing performance in the rotating device of the communication satellite directly affects its communication effect. If the bearing fails in aerospace, it will cause a serious accident.
Bearings are used in:
- Automotive: Rear wheels, transmissions, electrical components, small car front wheels, differential pinion shafts.
- Electrical: General Electric motors, household appliances.
- Industrial machinery: Internal combustion engines, construction machinery, railway vehicles, handling machinery, agricultural machinery, high-frequency motors, gas turbines, centrifugal separators, oil pumps, air compressors, fuel injection pumps, printing machinery, motors, generators, reduction gears, etc.