Designation system

The designations of most SKF rolling bearings follow a system that may consist of a basic designation with or without one or more prefixes and/or suffixes (→ Basic bearing designation system).
An example and the applicable options for thrust ball bearings are given below.
Basic bearing designation system

Example


51328 Mwhere51328 =
M =Test Designation 4
Test Designation 1Prefixes (n.a.)

Test Designation 2Basic designation
Listed in table 1
BA.Thrust ball bearing, bore diameter d < 10 mm
The one-digit number after BA identifies the bore diameter.

Catalogue image - Test Designation 3Suffixes - Internal design (n.a.)

Test Designation 4Suffixes - External design (seals, snap ring groove etc.) (n.a.)

Catalogue image - Test Designation 5Suffixes - Cage design
FMachined steel cage, ball centred
MMachined brass cage, ball centred

Catalogue image - Test Designation 6.1Suffixes - Materials, heat treatment (n.a.)

Test Designation 6.2Suffixes - Accuracy, clearance, preload, quiet running
P5Dimensional and geometrical to tolerances to class P5
P6
Dimensional and geometrical to tolerances to class P6

Catalogue image - Test Designation 6.3Suffixes - Bearing sets, matched bearings (n.a.)

Test Designation 6.4Suffixes - Stabilization (n.a.)

Suffixes - Lubrication (n.a.)

Test Designation 6.6Suffixes - Other variants (n.a.)
SKF logo