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 needle roller bearing components are given below.
Basic bearing designation system

Examples

IR 8x12x10 IS1whereIR 8x12x10 =
IS1 =
RN-3x19.8 BF/G2whereRN-3x19.8 =
BF =
G2 =
Test Designation 1
  Prefixes (n.a.)

Test Designation 2
Basic designation
IR
Needle roller bearing inner ring
LR
Needle roller bearing inner ring
RN
Needle roller

Catalogue image - Test Designation 3
Suffixes - Internal design
BF
Needle roller with flat ends
EGS
Inner ring with a non-directionally ground raceway
VGS
Inner ring with a pre-ground raceway and a machining allowance

Test Designation 4
Suffixes - External design (seals, snap ring groove etc.)
IS..Inner ring with lubrication hole(s), the number following indicates the number of holes
ISR..Inner ring with annular groove and lubrication hole(s), the number following indicates the number of holes

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
C2
Radial internal clearance smaller than Normal
C3
Radial internal clearance greater than Normal
C4
Radial internal clearance greater than C3
G2Needle roller in accordance with ISO 3096:1996 Grade 2
M../M..Diameter tolerance of needle rollers, e.g. M2/M4 indicates diameter tolerance –2 to –4 µm
N/M..Diameter tolerance of needle rollers, e.g. N/M2 indicates diameter tolerance 0 to –2 µm

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

Test Designation 6.4
Suffixes - Stabilization
S0Inner ring heat stabilized for operating temperatures ≤ 150 °C (300 °F)
S1Inner ring heat stabilized for operating temperatures ≤ 200 °C (390 °F)
S2Inner ring heat stabilized for operating temperatures ≤ 250 °C (480 °F)
S3Inner ring heat stabilized for operating temperatures ≤ 300 °C (570 °F)


Suffixes - Lubrication (n.a.)

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