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Designation system

The complete designation for an insert bearing or a ball bearing unit consists of a basic designation with or without one prefix and/or one or more suffixes.

For details about the insert bearing designation system, refer to Insert bearings.

Ball bearing units

Designation examples and the applicable options for ball bearing units are given below.
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Examples


Metric unit:
SYK 20 TDwhereSY =
K =
20 =
TD =
F4BC 50M-TPSSwhereF4B =
C =
50M =
TPSS =

Inch unit:
SY 2 11/16 LF/AH
whereSY =
2 11/16 =
LF
AH =

Applicable options for ball bearing units

Housing/unit type

J stands for dimensions in accordance with JIS 1559-2009 for normal base plummer block, flanged and take-up housings
F2B
Oval flanged housing
F3BB
3-bolt bracket flanged housing
F4B
Square flanged housing
FYSquare flanged housing
FYCRound flanged housing
FYT(B)Oval flanged housing
PPlummer block housing, pressed steel
P .. RPlummer block housing, pressed steel, rubber seating ring included
P2B
Plummer block housing, normal base
P2BT
Plummer block housing, short base
PF
Round flanged housing, pressed steel
PFDTriangular flanged housing, pressed steel
PFTOval flanged housing, pressed steel
SYPlummer block housing, normal base
SYFPlummer block housing, short base
TUTake-up housing
WSTUTake-up housing

Housing material
Grey cast iron
CComposite for the SKF Food Line
DSpheroidal graphite cast iron
K
Composite
SS
Stainless steel


Size identification
Bearing units for metric shafts: bearing bore uncoded
12
to
100
12 mm
to
100 mm
M
Metric size and metric threads, where applicable (only for the SKF Food Line units)
Standard bearing units for inch shafts: bearing bore uncoded
1/2
to
3
1/2 in. (12,7 mm)
to
3 in. (76,2 mm)
SKF Food Line bearing units for inch shafts: bearing bore coded

Three-digits combination that follows the housing/unit type and material identification of the unit designation: the first digit is the number of whole inches and the second and third digits are the number of sixteenths of an inch.
012
to
115
3/4 in. (19,05 mm)
to
1 15/16 in. (49,213 mm)
Housings made of cast iron, composite, composite for the SKF Food Line or stainless steel
503
to
520
for insert bearings of sizes 203, 203-008, 203/12 and 203/15
to
for insert bearings of size 220
Housings made of pressed steel (not supplied as bearing unit)
40
to
90
40 mm housing bore diameter
to
90 mm housing bore diameter

Additional housing features
D
Next larger size than normal (inch units only)
LNext larger size than normal (inch units only)
NRelubricable execution of a composite housing
S
Next smaller size than normal (inch units only)
U
Deviating housing features
YSuitable for ECW end cover
ZShort base and take-up unit with an inch thread (metric bearings only)

Inserted bearing
CPSSStainless steel insert bearing with grub screws, special bearing design for DFH units
FMInsert bearing with an eccentric locking collar, YET 2 series
KFInsert bearing with a tapered bore on an adapter sleeve, YSA 2-2FK series
LD, LDW
Insert bearing with SKF ConCentra locking, YSPAG 2 series
LFInsert bearing with SKF ConCentra locking, YSP 2-2F series
RM
Insert bearing with grub screws, YAT 2 series
TD, TDW
Insert bearing with grub screws, YARAG 2 series
TF
Insert bearing with grub screws, YAR 2-2F series
TPSS
Stainless steel insert bearing with grub screws, YAR 2-2LPW/SS series
TPZMInsert bearing with grub screws, zinc-coated inner and outer rings, YAR 2-2LPW/ZM series
TR
Insert bearing with grub screws, YAR 2-2RF series
WD, WDW
Insert bearing with an eccentric locking collar, YELAG 2 series
WFInsert bearing with an eccentric locking collar, YEL 2-2F series
WRInsert bearing with an eccentric locking collar, YEL 2-2RF series

Suffixes - other features
AHUnit for air-handling applications
DFHSealed unit (back seal and end cover installed)
VL065Zinc-coated bearing inner ring bore and side faces
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