Bearing accuracy and grade

The accuracy of the rolling bearing is divided into (main) dimensional accuracy and rotation accuracy. The accuracy level has been standardized and is divided into five levels: P0, P6, P5, P4, and P2.
      The accuracy is increased from the 0th level in order, and is sufficient for the general purpose 0 level, but when used in the conditions or occasions shown in Table 1, an accuracy of 5 steps or higher is required.
      Although the above accuracy levels are based on the ISO standard, their names are different in national standards.
      Table 2 lists the accuracy levels applicable to the various bearing types and the comparison between national standards.

      Dimensional accuracy (items related to shaft and housing installation)
      1. Allowable deviation of inner diameter, outer diameter, width and assembly width
      2. Allowable deviation of the diameter of the compound circle and the diameter of the outer complex circle in the roller group
      3, the allowable limit value of the chamfer size
      4, the allowable variation of the width

      Rotation accuracy (items related to the rotation of the rotating body)
      1. Allowable radial runout and axial runout of the inner and outer rings
      2, the inner ring allows lateral runout
      3. Allowable variation of the inclination of the outer diameter surface
      4. Allowable variation of the thickness of the thrust bearing raceway
      5. Allowable deviation and allowable variation of tapered bore