The maximum allowable speed, or limiting speed, of a bearing decreases with increasing diameter and width series. Bearing catalogs or design manuals list the limiting speed nlim values for various bearing types and sizes. These test conditions are: an equivalent dynamic load P <= 0.1C (C is the basic dynamic load rating), normal cooling conditions, and the maximum permissible speed for a Class 0 tolerance bearing.
However, since the limiting speed is primarily limited by operating temperature rise, the limiting speed listed in the catalog should not be considered an absolute limit that cannot be exceeded.
Each bearing has its own limiting speed, primarily limited by the temperature rise caused by internal frictional heat. When the speed exceeds a certain limit, the bearing may become unable to rotate due to burns or even seizure.
Therefore, before selecting the appropriate bearing type based on the bearing's speed, it is important to understand the speed requirements for bearing selection. In some applications, other factors may be more important than the limiting speed, such as low speeds and reciprocating motion.