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 alignment needle roller bearings are given below.
Basic bearing designation system


RPNA 15/28
whereR =
PNA 15/28 =
Test Designation 1
Bearing without an inner ring

Test Designation 2
Basic designation
Alignment needle roller bearing

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 (n.a.)

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

Test Designation 6.2Suffixes - Accuracy, clearance, preload, quiet running
C2Radial internal clearance smaller than Normal
C3Radial internal clearance greater than Normal
C4Radial internal clearance greater than C3

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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