Internal Design Suffixes
A, B, C Deviating or modified internal design
Suffixes - External design (seals, snap ring groove, etc.)
G Helical groove in inner ring bore
K Tapered bore, taper 1:12
K30 Tapered bore, taper 1:30
Suffixes - Cage design
F
Machined steel cage, roller centred
M Machined brass cage, roller centred
HA1 Case-hardened inner and outer rings
HA4 Case-hardened inner and outer rings and rollers
HA5 Case-hardened rollers
HB1 Bainite-hardened inner and outer rings
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
P = Displaced clearance range comprising the upper half of the actual clearance range plus the lower half of the next larger 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
W20 Lubrication holes in the outer ring
W33(X) Annular groove and lubrication holes in the outer ring
