Rolling bearing tolerance class classification

一、Grading of rolling bearings

·GB/T307.1-94 "Radial Bearing Tolerances" radial bearing tolerances other than tapered roller bearings are divided into levels 0, 6, 5, 4, and 2.

·The tolerances of tapered roller bearings are divided into levels 0, 6X, 5, and 4.

·GB/T307.4-94 "Thrust Ball Bearing Tolerances" thrust ball bearings are divided into grades 0, 6, 5 and 4.

·JB5286-91 "Supplementary Technical Conditions for Precision Rolling Bearings for Machine Tool Spindles" stipulates the SP and UP level tolerances of precision rolling bearings for machine tool spindles - double row cylindrical roller bearings.

·JB/T6362 "SP and UP level tolerances of bidirectional thrust angular contact ball bearings for machine tool spindles.

二、Contents included in rolling bearing tolerance levels

Rolling bearings include dimensional tolerances and geometric tolerances.

1.Dimensional tolerances, items related to shaft or bearing seat installation:

·Allowable deviations of inner diameter, outer diameter, ferrule width and assembly width.

·Allowable deviation of roller group diameter.

·Allowable limit value of chamfer size.

2.Geometric tolerances, items related to the runout of the rotating body:

·The allowable radial runout and end face runout values of the finished bearing (Kia, Kea, Sia,Sea,Sd, SD).

·Thrust bearing raceway thickness deviation (Si, Se).