Introduction to Bearings

Bearings are an essential component of a large number of machines that we use in our daily lives. If these machines worked without them, we would have to replace their components repeatedly, as they would deteriorate very often due to friction. Here you will get to know how they work, what are the different types of bearings, as well as some other interesting facts about them.

The basics

The idea behind the bearings becomes quite simple if you understand that it is easy to roll by sliding things. The wheels of the car are one kind of large bearings. Can you imagine how difficult it would have been to drive if your car had skies instead of wheels?

When you move something on a surface, friction naturally comes in and it slows it down. However, friction between the two rolling surfaces is significantly reduced.

We can overcome friction to a great extent by using bearings with smooth metallic balls/rollers, which are sandwiched between an inner and outer metal surface against which the balls rotate. These balls/rollers bear thrust and the device rotates smoothly.

Type

Bearings come in different designs and types for a variety of applications. The most common are ball and roller bearings. Then, we have roller thrust and ball thrust bearings, followed by tapered roller thrust bearings.

Ball bearings

They are easily the most frequently used bearings. You can find them in every item from skates to car wheels and even electronic drives. They are capable of bearing thrust, as well as radial loads. They are often used where the load is low.

In their case, the load is transferred from the outer race to the balls, and from there to the inner race. Since the balls are spherical, they make a point of contact with the outer and inner races, allowing the object to move freely. Since balls make only one point of contact, they cannot withstand much load. Therefore, if such bearings are overloaded, the balls get out of shape or burst, making the bearings useless.

Roller Bearing

Applications that are required to transmit heavy loads or radial loads, such as in the case of conveyor belts, necessarily require the use of Bearing Housing Cartridges. As the name suggests, there are rollers in cylindrical shape in place of balls. Since the contact area of ​​the roller is certainly much larger than the ball or sphere, these bearings have a greater contact area between the inner and outer casing. As a result, they are capable of supporting larger loads than ball bearings. However, this design cannot carry too much weight.

Needle bearings are types of Bearing Housing Cartridges. They have very small diameter cylinders. As a result, the bearing can also be fitted in tight spaces.

Ball thrust bearing

Sometimes, we need bearings that do not have to withstand too much radial load and operate at low speeds, as is the case with bar-stools and turntables. For such applications, ball thrust bearings are often used.

Roller Thrust Bearing

In applications with large loads, such as in the case of a car's transmission gear or housing of a rotating shaft, we use roller thrust bearings. Most transmission drives have helical gears with angled teeth, resulting in thrust loads that need to support the bearings.

Tapered Roller Bearings

Applications with large radial and thrust loads require the support of tapered roller bearings. Such bearings are often used in the hubs of cars. Typically, they are placed in pairs and facing in the opposite direction, enabling them to hold the thrust in either direction.

For some high-tech applications, special bearings need to be designed. Some examples of such bearings include giant roller bearings and magnetic bearings.