The accuracy of the bearing

Bearing accuracy and grade

The accuracy of rolling bearings is divided into (mainly) dimensional accuracy and rotational accuracy. The accuracy level has been standardized and divided into six levels: 0, 6X, 6, 5, 4, and 2

Grade.

Accuracy increases sequentially from class 0 onwards, and class 0 is sufficient for general use, but when used in the conditions or occasions shown in the table below, an accuracy of class 5 or higher is required. Although the above accuracy levels are based on ISO standards, they are called in various countries

There are differences in the standards.

Dimensional accuracy (items related to bearing housing mounting)

Inner diameter, outer diameter, width and assembly width allowed

The allowable deviation of the inner and outer compound circle diameter of the roller group

The allowable variation of the allowable limit value width of the deviation chamfer dimension

Permissible deviation and permissible variation of the conical hole

Rotation accuracy (items related to rotational body runout)

Allowable radial and axial run-out of the inner and outer rings

The inner ring allows lateral runout

The allowable variation of the inclination of the outer diameter surface

The allowable variation in the thickness of the raceway of the thrust bearing