Tolerances for total radial run-out
Depending on the application requirements, the total radial run-out tolerances as defined in ISO 1101:2012 should be one to two IT grades tighter than the prescribed dimensional tolerance. ISO 1101 defines the total radial run-out tolerance as a difference in radii of two coaxial cylinders. For example, if the specifications require a shaft seat in accordance with a tolerance class m6 , the total radial run-out should be IT5 or IT4. The tolerance value t3 for total radial run-out is obtained for an assumed shaft diameter of 150 mm from t3 = IT5/2 = 18/2 = 9 μm (difference in radii). Guideline values for the tolerances for total radial run-out are listed in table 1.
When bearings are to be mounted on adapter or withdrawal sleeves, the total radial run-out of the sleeve seat should be IT5/2 for tolerance class h9 (table 2).