6—Bearing Tolerances

Bearing tolerances indicate acceptable values for dimensions and running accuracy for a given tolerance class. Tolerances are standardized internationally by organizations including ISO, JIS, DIN, ANSI, and ABMA.

Bearing Tolerances

Bearing tolerances encompass both dimensional tolerances and permissible values that relate to running accuracy.

Tolerances and permissible values for boundary dimensions and running accuracy are specified in JIS B 1514, ISO 492 (radial bearings), and ISO 199 (thrust bearings).

Bearing Tolerance Classes

For most general applications, JIS 0 (ISO Normal class) is sufficient.

Class 5 or higher products are used in machine tool spindles, specialized instruments, and other precision equipment, as well as in high-speed applications such as aircraft.

Bearing tolerance classes arranged from low to high accuracy. For ISO, these are (in ascending order) Normal Class, Class 6X (tapered roller bearings only, Class 6, Class 5, Class 4 and Class 2, while in JIS these are Class 0, Class 6, Class 5, Class 5, and Class 2.