| Internal Design Suffixes | |
|---|---|
| A | Deviating or modified internal design |
| EC | Optimized internal design incorporating more and/or larger rollers and with modified roller end / flange contact |
| External Design Suffixes | |
|---|---|
| K | Tapered bore, taper 1:12 |
| N | Snap ring groove in the outer ring |
| NR | Snap ring groove in the outer ring, with associated snap ring |
| N1 | One locating slot (notch) in one outer ring side face |
| N2 | Two locating slots (notches) in one outer ring side face, 180° apart |
| Cage Design Suffixes | |
|---|---|
| FR | Pin-type steel cage, pierced rollers |
| J | Stamped steel cage, roller centred |
| L | Machined light alloy cage, roller centred |
| LA | Machined light alloy cage, outer ring centred |
| LB | Machined light alloy cage, inner ring centred |
| LL | Machined light alloy cage, window-type, inner or outer ring centred (depending on bearing design) |
| M | Machined brass cage, roller centred |
| MA(S) | Machined brass cage, outer ring centred. The S indicates a lubrication groove in the guiding surface. |
| MB | Machined brass cage, inner ring centred |
| ML | Machined brass cage, window-type, inner or outer ring centred (depending on bearing design) |
| MP | Machined brass cage, window-type, inner or outer ring centred (depending on bearing size) |
| MR | Machined brass cage, window-type, roller centred |
| P | Glass fibre reinforced PA66 cage, roller centred |
| PA | Glass fibre reinforced PA66 cage, outer ring centred |
| PH | Glass fibre reinforced PEEK cage, roller centred |
| PHA | Glass fibre reinforced PEEK cage, outer ring centred |
| Materials, heat treatment Suffixes | |
|---|---|
| HA1 | Case-hardened inner and outer rings |
| HA2 | Case-hardened outer ring |
| HA3 | Case-hardened inner ring |
| HB1 | Bainite-hardened inner and outer rings |
| HB2 | Bainite-hardened outer ring |
| HB3 | Bainite-hardened inner ring |
| HN1 | Inner and outer rings with special surface heat treatment |
| Accuracy, Clearance, Preload, Quiet Running Suffixes | |
|---|---|
| CN | Normal radial internal clearance; only used together with an additional letter that identifies a reduced or displaced clearance range |
| H | Reduced clearance range corresponding to the upper half of the actual clearance range |
| L | Reduced clearance range corresponding to the lower half of the actual clearance range |
| M | Reduced clearance range corresponding to the middle half of the actual clearance range |
| The above letters are also used together with the clearance classes C2, C3, C4 and C5, e.g. C2H. | |
| C2 | Radial internal clearance smaller than Normal |
| C3 | Radial internal clearance greater than Normal |
| C4 | Radial internal clearance greater than C3 |
| C5 | Radial internal clearance greater than C4 |
| Bearing sets, matched bearings Suffixes | |
|---|---|
| DR | Set of two matched bearings |
| TR | Set of three matched bearings |
| QR | Set of four matched bearings |
| Stabilization Suffixes | |
|---|---|
| S1 | Bearing rings heat stabilized for operating temperatures ≤ 200 °C (390 °F) |
| S2 | Bearing rings heat stabilized for operating temperatures ≤ 250 °C (480 °F) |
| Lubrication Suffixes | |
|---|---|
| W33 | Annular groove and three lubrication holes in the outer ring |
Internal Design Suffixes
A Deviating or modified internal design
EC Optimized internal design incorporating more and/or larger rollers and with modified roller end / flange contact
Suffixes - External design (seals, snap ring groove, etc.)
K
Tapered bore, taper 1:12
N Snap ring groove in the outer ring
NR Snap ring groove in the outer ring, with associated snap ring
N1 One locating slot (notch) in one outer ring side face
N2 Two locating slots (notches) in one outer ring side face, 180° apart
Suffixes - Cage design
FR
Pin-type steel cage, pierced rollers
J Stamped steel cage, roller centred
L
Machined light alloy cage, roller centred
LA
Machined light alloy cage, outer ring centred
LB
Machined light alloy cage, inner ring centred
LL
Machined light alloy cage, window-type, inner or outer ring centred (depending on bearing design)
M
Machined brass cage, roller centred
MA(S) Machined brass cage, outer ring centred. The S indicates a lubrication groove in the guiding surface.
MB Machined brass cage, inner ring centred
ML Machined brass cage, window-type, inner or outer ring centred (depending on bearing design)
MP Machined brass cage, window-type, inner or outer ring centred (depending on bearing size)
MR Machined brass cage, window-type, roller centred
P Glass fibre reinforced PA66 cage, roller centred
PA Glass fibre reinforced PA66 cage, outer ring centred
PH Glass fibre reinforced PEEK cage, roller centred
PHA Glass fibre reinforced PEEK cage, outer ring centred
HA1 Case-hardened inner and outer rings
HA2 Case-hardened outer ring
HA3 Case-hardened inner ring
HB1
Bainite-hardened inner and outer rings
HB3 Bainite-hardened inner ring
HN1 Inner and outer rings with special surface heat treatment
Suffixes - Accuracy, clearance, preload, quiet running
CN Normal radial internal clearance; only used together with an additional letter that identifies a reduced or displaced clearance range
H = Reduced clearance range corresponding to the upper half of the actual clearance range
L = Reduced clearance range corresponding to the lower half of the actual clearance range
M = Reduced clearance range corresponding to the middle half of the actual clearance range
The above letters are also used together with the clearance classes C2, C3, C4 and C5, e.g. C2H.
C2 Radial internal clearance smaller than Normal
C3 Radial internal clearance greater than Normal
C4 Radial internal clearance greater than C3
C5 Radial internal clearance greater than C4
Suffixes - Bearing sets, matched bearings
DR Set of two matched bearings
TR Set of three matched bearings
QR Set of four matched bearings
Suffixes - Stabilization
S1 Bearing rings heat stabilized for operating temperatures ≤ 200 °C (390 °F)
S2 Bearing rings heat stabilized for operating temperatures ≤ 250 °C (480 °F)
Suffixes - Lubrication
W33 Annular groove and three lubrication holes in the outer ring
Suffixes - Other variants
PEX
SKF Explorer bearing, used only when same-sized conventional and SKF Explorer bearings are available
VA301
Bearing for railway vehicle traction motors
VA305 VA301 + special inspection routines
VA350 Bearing for railway axleboxes
VA380 Bearing for railway axleboxes in accordance with EN 12080, class 1
VA3091 VA301 + external surfaces of the outer ring are coated with aluminium oxide
VC025
Bearing with special wear-resistant raceways for applications in heavily contaminated environments
VE901 Modified internal design
VQ015 Inner ring with crowned raceway for increased permissible misalignment
