How do bearings work?

A bearing is a device that is basically used to carry a weight form of load to provide the smooth operation of an application. There are usually two types of loads, radial and thrust, depending on the weight and type of application they come from.There are various kinds of bearings specifically designed for certain applications, which depends on the expected loads and the chances of temperature fluctuations, contaminant exposure, and pressure.

If you look closely at turbine bearings and slewing rings, they can be as large as 2m in diameter and often they handle hundreds of tonnes. In addition, there are bearings for different medical applications, but they appear in smaller machines with diameters of only a few millimeters. So you can look at the different applications and uses of different bearings.

Ball Bearings
Ball bearings have balls that provide the rolling element for the purpose of low-friction motion between two races of the bearing. They are quite cost effective and they require low maintenance too. Ball bearings generate low heat, which makes them widely selected for motion system applications. You can find ball bearings in almost everything from turbine engines and skateboard wheels to medical equipment and aerospace applications.

Roller Bearings
Roller bearings are different from ball bearings, as they have rollers of different shapes for transmitting loads and reducing friction. Due to their design, they have a larger surface contact area compared to ball bearings, and so, they can accommodate larger loads without deformation. This kind of bearing distributes weight evenly over cylinder line contacts, that allow moderate thrust loads and is particularly useful for turbine engines, conveyor belt rollers, gearboxes and transmissions, mining, pulp and paper, food and beverage, and waste-water industries.

A roller bearing that has rollers with a length of at least four times their diameter is known as a needle roller bearing. They are used in high radial loads in rocker arm pivots, compressors, transmissions and pumps. They are also commonly used in agricultural equipment, construction equipment, two-cycle engines, and paper moving equipment.

Thrust Ball Bearings
Thrust ball bearings are generally used for applications with primarily axial loads. They are capable of handling shaft misalignment. Additionally, they excel in high-speed applications for the automotive and aerospace industries and spindles, machine tool tables, fluid control valves. Moreover, they transmit load the bearing raceway to handle radial loads. The applications using these bearings include crane hooks, pulverizers, cone crushers and other heavy-load, medium-speed applications.

Tapered Roller Bearings
Tapered roller bearings consist of tapered rollers between tapered inner and outer ring raceways. These rollers are angled, so their surfaces converge at the bearing axis. Unlike other bearings, these accommodate either axial or radial loads. Moreover, they also handle large loads in either direction. They are usually used in applications like fuel pumps, helicopter transmissions, agricultural uses, and more.

Plain Bearings
Plain bearings do not have any rolling elements. They are considered to be the compact and low-cost bearings for many of the applications. Among all the applications, automotive and construction are the most common ones that use these bearings. Plain bearings also go in steering cylinders, hydraulic excavators, and more.