滿天飛的 的部落格

bearing friction
Friction is the resistance of two elements that are in contact with each other during motion. Torque is the name that we give to the force that appears when elements are sliding or trying to slide on any surface. These foces always affect motion and can be present in water or air. Friction is present whenever an element is moving or has the tendency ot move. This is symbolized by the arrows pointed in the opposite direction of the motion or in the opposite direction of the tendency of this motiion.

There are two kinds of friction: Static friction and Dynamic friction. Static friction is the resistance when an object is in a stationary position. This force works in the opposite direcslide bearing tion of the object's movement.

Dynamic friction is the resistance when an object is already in motion. The value of the friction is equal to the value of the energy required to keep the object in motion. The required force is much less in the case of dynamic friction than static friction.

The force necessary to accomplish the rolling motion is much less than the force necessary to accomplish the sliding motion under normal operating conditions.

Bushings are one type of bearings. Bushing are used when there is rotation between the shaft and housing in the form of sliding motion. The friction present changes from static to dynamic when a bushing is in motion. This amount of force is what is required to accomplish the work of this rotation.

Static friction exists between the rolling elements of the bearing and the inner and outer rings of the bearing when at rest. Bearings are used to create rolling motion in order to minimize dynamic friction. As a result, less force and energy are required to keep a shaft and housing in motion. One of the most common uses of a rolling bearing is in the wheel of a car.

remark:
Rolling bearings offer the following advantages:
1. They reduce both static and dynamic friction.
2. They can simplify an application making maintenance and inspection easier.
3. In general, rolling bearings can support radial and thrust loads simultaneously.
4. They can be used in both high and low temperature applications.
5. They can be preloaded to increase rigidity.