Comparison of preload method and speed influence between ceramic ball bearing and all-steel bearing

The stiffness variation of ceramic ball bearings is similar to that of all-steel bearings, but the variation is relatively gentle.

Under positioning pretension, the centrifugal force of the inner ring and the ball, and the action of friction heat increase the contact load of the inner and outer rings, while the contact angle of the outer ring decreases, and the contact angle of the inner ring increases, thereby increasing the contact stiffness, but the outer ring is in contact The decrease in angle slows down the increase in axial and angular stiffness.

Under constant pressure preload, the centrifugal force of the ball increases so that the contact load of the outer ring increases, while the contact angle decreases. Since the inner and outer rings allow axial displacement, the contact load of the inner ring remains basically unchanged, but the contact angle increases. Thermal displacement and centrifugal displacement have almost no effect on the contact load and contact angle of the inner and outer rings.

Although the normal contact stiffness of the outer ring increases, the normal contact stiffness of the inner ring remains basically unchanged. The result of the series action increases the radial stiffness, but not much, while the decrease in the contact angle of the outer ring makes the axial and angular stiffness Significantly reduced.

Under positioning preload, the stiffness of ceramic ball bearings is lower than that of all-steel bearings, while under constant pressure preloading, the stiffness of ceramic ball bearings is greater than that of all-steel bearings.

Under positioning preload, the contact load of the all-steel bearing is more than twice higher than that of the ceramic ball bearing. Although the elastic modulus of the ceramic ball is high, the stiffness of the all-steel bearing is greater than that of the ceramic ball bearing. Under constant pressure preload, the contact load of the inner ring does not change much, and the high elastic modulus of the ceramic ball makes the stiffness of the ceramic ball bearing greater than that of the all-steel bearing.