How to test the accuracy of the bearing with preload method '

Kunshan bearings: preload bearing by means before loading by changing the relative positions of inner and outer rings, the bearing clearance in use. For household appliances bearing preload main role is to improve the bearing stiffness, vibration and noise suppression.
Preload of the bearing noise
Bearing under radial load, due to the presence radial clearance, only part of the ball bear the load, called the bearing area, the other is called non-bearing area. In the ball bearing zone from the non-D motion to D 'in the process, the ball weight and the centrifugal force of the magnitude and direction changing, alternating balls collide with the inner and outer ring raceways, so that different sounds generated within the bearing. This different sound can be eliminated on the bearing preload.
However, the Ambassador preload bearing friction increases, the temperature rises, the bearing life is reduced noise. So select the appropriate preload is very important.
(A) measuring the shaft and the bearing manufacturer hole size to determine with precision bearings, with the following requirements:
Take the inner ring and the shaft interference fit, the amount of interference 0 ~ +4 μm (at light load, high precision is 0); take the outer ring and the bearing bore clearance fit, clearance volume 0 ~ +6 μm (but at the free end of the bearing use angular contact ball bearings, also increase the gap); shaft and housing bore surface roundness error in 2μm or less, used in the bearing spacer Parallelism in 2μm or less, the inner face of external shaft shoulder end of the beating in the 2μm the following; shoulder block bearing bore axis of the beating in the 4μm for the following; inner end face of the spindle axis of the front cover of the beating in the 4μm less.
 (2) fixed end mounted on the shaft front bearing
Cleaning the bearing with clean kerosene thoroughly cleaned, for grease lubrication, the first containing 3% to 5% of the grease into the bearing organic solvent for degreasing, then the grease gun to the grease filled in the bearing quantitative (representing bearing space volume of 10% to 15%); heating bearings make heating 20 ~ 30 ℃, oil presses the bearing onto the shaft; tight sets will be pressed on the shaft and in the appropriate pressure against the bearing face axially positioning; would spring balance tape volumes in the bearing outer ring, with the measurement method of starting torque required preload check whether there is a significant change (even if the bearings are correct, but due to the deformation of the cage match or pre-load is also may change).