Bearing terminology

Principles of bearing selection and application

20

1 23

4

5

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8

9

10

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10 1118

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1

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4

Bearing arrangement (➔ fig )1 Cylindrical roller bearing2 Four-point contact ball

bearing3 Housing4 Shaft5 Shaft abutment shoulder6 Shaft diameter7 Locking plate8 Radial shaft seal 9 Distance ring10 Housing bore diameter11 Housing bore12 Housing cover13 Snap ring

Radial bearings (➔ figsand )1 Inner ring2 Outer ring3 Rolling element: ball,

cylindrical roller, needleroller, tapered roller, spherical roller

4 Cage5 Capping device

Seal – made of elastomer,contacting (shown in figure)or non-contactingShield – made of sheetsteel, non-contacting

6 Outer ring outside diameter7 Inner ring bore8 Inner ring shoulder diameter9 Outer ring shoulder diameter10 Snap ring groove11 Snap ring12 Outer ring side face13 Seal anchorage groove

3

2

1

1Fig

2Fig

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α

α

14

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6

2

12

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4

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1

7

24

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26

27

24

28

24

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26

14 Outer ring raceway15 Inner ring raceway16 Sealing groove17 Inner ring side face18 Chamfer 19 Bearing mean diameter20 Total bearing width21 Guiding flange22 Retaining flange23 Contact angle

Thrust bearings (➔ fig )24 Shaft washer25 Rolling element and

cage assembly26 Housing washer27 Housing washer with

sphered seating surface28 Seating support washer

4

3Fig

4Fig

Footnote ➔ page 31

Radial bearings

Deep groove ball bearingssingle row, with or without filling slots

open basic design (1)with shieldswith contact seals (2)with snap ring groove, with or withoutsnap ring

single row with fixed sectionopen basic design (3)with contact seals

double row (4)

Angular contact ball bearingssingle row

design for universal matching (5)basic design for single mounting

single row high precision1)

standard design for single mounting (6)design for universal matchingmatched bearing sets

double rowwith one-piece inner ring (7)

open basic designwith shieldswith contact seals

with two-piece inner ring

Bearing types

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1

3

5

2

4

6

7

Bearing types

24

Radial bearings

Four-point contact ball bearings (8)

Self-aligning ball bearingswith cylindrical or tapered bore

open basic design (9)with contact seals (10)

with extended inner ring (11)

Cylindrical roller bearingssingle row

NU type (12)N type (13)

NJ type (14)NUP type (15)

angle ring (16)for NU and NJ type bearings

8

11

109

1312

1514

16

25

Radial bearings

Cylindrical roller bearingsdouble row1)

with cylindrical or tapered boreNNU type (17)NN type (18)NNUP type

four-row2)

with cylindrical or tapered boreopen design (19)with contact seals

Full complement cylindrical roller bearingssingle row

NCF type (20)NJG type (21)

double rowwith integral flanges on the inner ring (22)with integral flanges on the inner and outer rings with contact seals (23)

Needle roller and cage assemblies3)

single row (24)double row (25)

Drawn cup needle roller bearings, open ends3)

single and double rowopen basic design (26)with contact seals (27)

1817

2120

2322

2524

2726

19

Footnote ➔ page 31

Radial bearings

Drawn cup needle roller bearings, closed end3)

single and double rowopen basic design (28)with contact seal (29)

Needle roller bearings with flanges3)

single and double rowwithout inner ring (30)with inner ring

open basic designwith contact seals (31)

Needle roller bearings without flanges3)

single and double rowwith inner ring (32)without inner ring (33)

Alignment needle roller bearings3)

without inner ringwith inner ring (34)

Combined needle roller bearings3)

Needle roller/angular contact ball bearingssingle direction (35)double direction (36)

Needle roller/thrust ball bearingswith full complement thrust ball bearing (37)with cage-guided ball set

with or without (38) cover

Bearing types

26

28 29

30 31

32 33

35 36

37 38

34

Footnote ➔ page 31

Radial bearings

Needle roller/cylindrical roller thrust bearingswithout cover (39)with cover (40)

Taper roller bearingssingle row

single bearings (41)matched bearing sets

face-to-face (42)back-to-backin tandem

double row2)

TDO configuration (back-to-back) (43)TDI configuration (face-to-face) (44)

four-row2)

TQO configuration (45)TQI configuration

Spherical roller bearingswith cylindrical or tapered bore

open basic designs (46)with contact seals (47)

CARB toroidal roller bearingswith cylindrical or tapered bore

open basic designs with cage-guided roller set (48)

with full complement roller setwith contact seals (49)

27

39 40

41 42

43 44

46 47

48 49

45

Footnote ➔ page 31

Thrust bearings

Thrust ball bearings single direction

with flat housing washer (50)with sphered housing washer

with (51) or without seating washer

double direction with flat housing washers (52)with sphered housing washers

with (53) or without seating washers

Angular contact thrust ball bearings1)

high precision bearingssingle direction

standard design for single mounting (54)design for universal matchingmatched bearing sets (55)

double directionstandard design (56)high-speed design (57)

Cylindrical roller thrust bearingssingle direction

single row (58)double row (59)

componentscylindrical roller and cage thrust assembliesshaft and housing washers

Needle roller thrust bearings3)

single direction (60)needle roller and cage thrust assemblies raceway washersthrust washers

Bearing types

28

50 51

52 53

54 55

56 57

58

60

59

Footnote ➔ page 31

Thrust bearings

Spherical roller thrust bearingssingle direction (61)

Taper roller thrust bearings2)

single directionwith or without (62) coverscrew down bearings

double direction (63)

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61

6362Footnote ➔ page 31

Track runner bearings

Cam rollerssingle row ball bearing cam roller (64)double row ball bearing cam roller (65)

Support rollers3)

without axial guidancewith or without contact seals

without inner ringwith inner ring (66)

with axial guidance by thrust washerswith or without contact seals

with cage-guided needle roller set (67)full complement

with axial guidance by cylindrical rollerswith labyrinth seals (68)with contact seals (69)with lamellar seals

Cam followers3)

with axial guidance by thrust platewith or without contact seals

with concentric seating (70)with eccentric seating collar with cage-guided needle roller set with full complement needle roller set

with axial guidance by cylindrical rollerswith labyrinth seals (71)with contact sealswith concentric seatingwith eccentric seating collar

Bearing types

30

64

66

67

70

71

6968

65

Footnote ➔ page 31

Y-bearings

Y-bearings (insert bearings)4)

with grub screw lockinginner ring extended on one side (72)inner ring extended on both sides (73)

with eccentric locking collarinner ring extended on one side (74)inner ring extended on both sides (75)

with tapered boreinner ring extended on both sides (76)for adapter sleeve mounting

with standard inner ringfor locating by interference fit on the shaft (77)

31

1) See SKF catalogue “High-precision bearings” or “SKF Interactive Engineering Catalogue”2) See “SKF Interactive Engineering Catalogue”3) See SKF catalogue “Needle roller bearings” or “SKF Interactive Engineering Catalogue”4) See SKF catalogue “Y-bearing units” or “SKF Interactive Engineering Catalogue”

72 73

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77

75