Bearing 6321, dimensions 105 x 225 x 49 mm: SKF, NSK, NTN, RKB, TIMKEN, FAG, and KOYO part numbers

There are 3 bearing types with this size: deep groove ball bearings (13 part numbers, series 63), cylindrical roller bearings (12 part numbers, series N 3, NJ 3, and NU 3), and angular contact ball bearings (11 part numbers, series 73). Each type has its own table: they share the same size, but they do not work the same way and are not interchangeable.

11 of the 36 part numbers are the basic designation alone, without a suffix. The most frequent suffixes, with the number of part numbers they appear in: B (4), C3 (4), ECJ (4), ECP (3), and ZZ (2).

These are boundary dimensions according to ISO 15, in millimetres: d is the bore, D the outside diameter and B the width.

Two bearings with the same size are not necessarily the same bearing: the type, the seals or shields, the internal clearance, the cage and the load rating depend on the designation, the suffix and the brand. That is why we quote by part number: send us the full part number shown on the bearing, the box or the drawing, or the size together with the variant you need.

If the part number can no longer be read, measure the bore, the outside diameter and the width, and look the size up in the bearings-by-size index: each size has its own page with all its part numbers.