Ball bearing structure
The ball bearing is mainly composed of four basic components: a ball, an inner ring, an outer ring and a retainer called a cage or retainer. General industrial ball bearings meet the AISI 52100 standard. Balls and rings are usually made of high chrome steel with a Rockwell C-scale hardness of between 61 and 65. The hardness of the retainer is lower than that of the ball and the ring, and the material is metal (such as: medium carbon steel, aluminum alloy) or non-metal (such as: Teflon, PTEF, polymer material). The ball bearing has a lower rotational frictional resistance than the journal bearing, so the friction produces a lower temperature at the same speed.