A bearing number is composed of a basic number and a supplementary code, denoting bearing specifications including bearing type, boundary dimensions, running accuracy, and internal clearance. Bearing numbers of standard bearings corresponding to JIS B 1512 "rolling bearing boundary dimensions" are prescribed in JIS B 1513. As well as these bearing numbers, JTEKT uses supplementary codes other than those provided by JIS. Among basic numbers, bearing series codes are listed in Table 6-1 Bearing series code, and the composition of bearing numbers is described in Table 6-2 Bearing number configuration, showing the order of arrangement of the parts.

BearingsMaths

Types ofbearings

[Notes] 1) Width series codes in parentheses are omitted in bearing series codes. 2) These are bearing series codes customarily used. 3) Nominal outer ring width series (inner rings only are wide). 4) Besides NU type, NJ, NUP, N, NF, and NH are provided.