Types of Wheel Bearingsby Sharideth Smith
When a wheel turns, it generates a certain amount of friction. The heavier the bearing on the wheel, the greater the resistance--thus the name "wheel bearing" for the component that reduces the friction between parts as the wheel spins. Relieving the resistance between the moving parts in a wheel reduces erosion and wear, prolonging the life of the wheel. The application of each type of bearing depends on the purpose of the wheel.
Easily the most common type of wheel bearing, the ball bearing is also the most versatile. Ball bearings have the ability to absorb both radial and thrust loads. Radial load is the amount of weight put on a wheel. The thrust load is the cornering pressure. Ball bearings can be found in wheels as small as those on roller skates to tires as large as those on automobiles.
Roller bearings are also commonly used wheel bearings; however, they do not have the versatility of ball bearings. They handle radial load well, but do not hold up under thrust. This makes them virtually unusable in wheels that have to corner with even moderate amounts of speed. However, they work well for wheels on items like handtrucks or grocery carts.
Tapered Roller Bearings
Tapered roller bearings are most often used in standard car and truck and wheels. The cone shape allows for the reduction of friction during cornering when thrust load is at its greatest. When a car turns, the wheels angle to varying degrees. Tapered roller bearings allow for this to keep shifting parts from grinding.
Precision Ball Bearings
Precision ball bearings are designed for high pressure and high performance use. They reduce friction to a minimum, do not generate as much heat and have a higher rotation speed than standard bearings. Precision ball bearings are used in world class racing cars and airplane landing wheels. They are specifically designed for intense radial and thrust loads.
- photo_camera bearings image by petar Ishmeriev from Fotolia.com