Page 517 - Rollingbearings
P. 517
Designation system
Group 4
4 1 4 2 4 3 4 4 4 5 4 6
Group 4.6: 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 Modiied internal design
VQ015 Inner ring with crowned raceway for increased permissible misalignment
Group 4.5: Lubrication
W33 Annular groove and three lubrication holes in the outer ring
6
Group 4.4: 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)
Group 4.3: Bearing sets, matched bearings
DR Set of two matched bearings
TR Set of three matched bearings
QR Set of four matched bearings
Group 4.2: Accuracy, clearance, preload, quiet running
CN Normal radial internal clearance; only used together with an additional letter that identiies 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
Group 4.1: Materials, heat treatment
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
L4B Bearing rings and rollers black oxidized
L5B Rollers black oxidized
L7B Inner ring and rollers black oxidized
515
