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


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

Test Designation 2
Basic designation
Listed in table 1

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

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

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

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

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

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

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

Suffixes - Lubrication (n.a.)

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