Centrifugal force acts upon the entire mass of a rotating component, impelling each particle outward and away from the axis of rotation in a radial direction. If the mass of a rotating component is evenly distributed about its shaft axis, the part is "balanced" and rotates without vibration. However, if an excess of mass exists on one side of a rotor, the centrifugal force acting upon this heavy side exceeds the centrifugal force exerted by the light side and pulls the entire rotor in the direction of the heavy side. An unbalanced rotor will cause vibration and stress in the rotor itself and in its supporting structure. Balancing of the rotor is therefore necessary. Unbalance in just one rotating component of an assembly may cause the entire assembly to vibrate. This induced vibration in turn may cause excessive wear in bearings, bushings, shafts, spindles, gears, etc., substantially reducing their service life. Vibrations setup highly undesirable alternating stresses in structural supports and housings which may eventually lead to their complete failure. Performance is decreased because of the absorption of energy by the supporting structure. Vibrations may be transmitted through the floor to adjacent machinery and seriously impair its accuracy or proper functioning. Vibration Analysis Technical Papers Machine Balancing Standards ISO1949 and ANSI219 Click for full report Machine Balancing Grades of Motor Quality Bearing Life Click for full report Machine Balancing Vibration Reduction on Bearing Life