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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 self-aligning ball bearings are given below.
Basic bearing designation system


2306 E-2RS1KTN9
where2306 =
E =Test Designation 4
2RS1 =Test Designation 4
K =Test Designation 4
TN9 =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
EOptimized internal design

Test Designation 4
Suffixes - External design (seals, snap ring groove etc.)
Contact seal, NBR, on both sides
Tapered bore, taper 1:12

Catalogue image - Test Designation 5
Suffixes - Cage design
Machined brass cage, ball centred
PA66 cage, ball centred
Glass fibre reinforced PA66 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
Radial internal clearance smaller than Normal
Radial internal clearance greater than Normal

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

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

Suffixes - Lubrication
Solid Oil

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