A surprisingly large number of bearings can be found all around us. Take automobiles, for example: there are 100 to 150 bearings in a typical car. Without bearings, the wheels would rattle, the transmission gear teeth wouldn't be able to mesh, and the car wouldn't run smoothly.
Bearings are not used only in cars, but in all kinds of machinery such as:
trains
airplanes
washing machines
refrigerators
air conditioners
vacuum cleaners
photocopy machines
computers
satellites
Bearings enhance the functionality of machinery and help to save energy. Bearings do their work silently, in tough environments, hidden in machinery where we can't see them. Nevertheless, bearings are crucial for the stable operation of machinery and for ensuring its top performance.
The word "bearing" incorporates the meaning of "to bear," in the sense of "to support," and "to carry a burden." This refers to the fact that bearings support and carry the burden of revolving axles.
The two pictures below show the most basic bearings, known as rolling bearings.
Rolling bearing
Rolling bearing
(Ball bearing)
Rolling bearing
Rolling bearing
(Roller bearing)
Rolling bearings are made up of four elements and have an extremely simple basic structure.
Outer ring:
Outer ring:
The large ring of the outer race
Inner ring:
Inner ring:
The small ring of the inner race
Rolling elements:
Rolling elements:
Several balls or rollers that are contained in the space between the outer race and inner race
Cage:
Used to fix the position of the rolling elements
The basic function of bearings is principally to reduce mechanical friction. Reducing friction means:
machinery will run more efficiently
there will be less frictional wear, extending the operating life of the machinery
preventing abrasion burn, avoiding mechanical breakdown
Bearings also contribute to lower energy consumption by reducing friction and allowing the efficient transmission of power. This is just one way in which bearings are environmentally friendly.