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).
Examples and the applicable options for matched single row tapered roller bearings are given below.
Basic bearing designation system

Examples

31324 X/DFwhere31324 =
X =
DF =
32232T179/DB32C230where32232 =
T179 =
DB32, C230 =
Test Designation 1Prefixes (n.a.)

Test Designation 2Basic designation
Refer to Bearing designations or drawing number identification

Catalogue image - Test Designation 3Suffixes - Internal design
BSteep contact angle

Test Designation 4Suffixes - External design (seals, snap ring groove etc.)
T..
A number immediately following the T identifies the total width of matched bearings, arranged back-to-back or in tandem.
XBoundary dimensions changed to conform to ISO

Catalogue image - Test Designation 5Suffixes - Cage design (n.a.)

Catalogue image - Test Designation 6.1Suffixes - Materials, heat treatment
HA1Case-hardened inner and outer rings
HA5Case-hardened rollers

Test Designation 6.2Suffixes - Accuracy, clearance, preload, quiet running
CL7CHigh-performance design (available on request)
P5
Geometrical tolerances to P5 tolerance class
U..
U combined with a one- or two-digit number identifies tighter total width tolerance, e.g.:
U2 → +5/0 µm
U4 → +10/0 µm
W
Modified ring width tolerance to +5/0 µm

Catalogue image - Test Designation 6.3Suffixes - Bearing sets, matched bearings
DB..
Two bearings matched for mounting back-to-back. A number immediately following the DB identifies the design of the ring spacers.
DF..
Two bearings matched for mounting face-to-face. A number immediately following the DF identifies the design of the ring spacer.
DT..
Two bearings matched for mounting in tandem. A number immediately following the DT identifies the design of the ring spacers.
C...
Special clearance. The two- or three-digit number immediately following the C is the mean axial internal clearance in μm. The range remains the same as specified in table 1.

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

Test Designation 6.5Suffixes - Lubrication (n.a.)

Test Designation 6.6Suffixes - Other variants
PEX
SKF Explorer bearing, used only when same-sized basic design bearing and SKF Explorer bearing are available
VA321Optimized internal design
VA606Crowned raceway on the outer ring, logarithmic profile on the inner ring and special heat treatment
VA607Same as VA606, but other outside diameter tolerance
VB022Chamfer dimension of large outer ring side face 0,3 mm
VB026Chamfer dimension of large inner ring side face 3 mm
VB061Chamfer dimension of large inner ring side face 8 mm
VB134Chamfer dimension of large inner ring side face 1 mm
VB406Chamfer dimension of large inner ring side face 3 mm and of large outer ring side face 2 mm
VB481Chamfer dimension of large inner ring side face 8,5 mm
VC027
Modified internal geometry for increased permissible misalignment
VC068
Tighter geometrical tolerances and special heat treatment
VE141
One locating slot (notch) in the outer ring
VE174One locating slot (notch) in the large side face of the outer ring, tighter geometrical tolerances
VQ051Modified internal geometry for increased permissible misalignment
VQ117Special radial and axial run-out tolerances
VQ267Tighter inner ring width tolerance to ± 25 µm
VQ492Special inner ring width tolerance
VQ494Tighter radial run-out tolerances
VQ495
CL7C with tighter or shifted tolerance range for the outside diameter
VQ506
Tighter inner ring width tolerance
VQ507
CL7C with tighter or shifted tolerance range for the outside diameter
VQ523
CL7C with tighter inner ring width tolerance and tighter or shifted tolerance range for the outside diameter

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