Angular contact ball bearings
Angular contact ball bearing has high limit rotational speed, they can carry radial load and axial load simultaneously, they can also withstand purely radial load. The axial load carrying capacity depends on the magnitude of contact angle and increases with increasing contact angle.
Structures
1. Non-separable angular contact ball bearings
This inner ring and outer ring of this type of bearings cannot be separated and comprises following structures:
Contact angle α=15° counter bore on outer ring,7000Ctype
Contact angle α=25° counter bore on outer ring,7000ACtype
Contact angle α=40° counter bore on outer ring, 7000B type
2. Four-point contact ball bearings
This type of bearings is separable bearings. Whereof, QJ0000 type has two-piece inner ring and QJF0000 type has two-piece outer ring. Their contact angles are same as 35°.When received no load or pure radial load, the steel balls of the ball bearing contact with the four points of the rings. When it is received a pure axial load, the steel balls perform a two-point contact with the ring. In addition, besides the axial load from both directions, this kind of bearing can take torque-load as well.
3. Double row angular contact ball bearings
This kind of bearings can accommodate radial loads as well as axial loads acting in both directions; they can also take loading moment. They can restrain the axial displacement from both directions of the shaft or housing; the contact angle is 30° (or 40°)
Permissible tilt angle
There is only a little inclination between the inner ring and outer ring of angular contact bearings, the permissible tilt angle varies according to the internal clearance when the bearings are operating, the bearing dimensions, internal design, force and loading moment received by the bearings. The value of the maximum permissible tilt angle should be able to ensure that no much extra stress to be generated inside the bearings.
The tilt angle existing between the inner ring and outer ring will influence the bearing service life. Meanwhile, the running accuracy is decreased down and noise increased.
Tolerance and clearance
The tolerances of general angular contact bearings are class normal P0, class P5 and P6. Class P4 and P2 are applicable to machine tool spindles and bearing amount in pairs.
Clearance of single row angular contact bearing is decided by the contact angle, which is guaranteed by manufacturing.
Axial clearance of Four-point contact ball bearings is listed in table 1.
Cage material
Generally, the cage of angular contact bearing is pressed cage of steel sheet or brass cage, and it is solid brass cage for two row angular contact bearing.
Dynamic equivalent radial load
Single-row angular contact ball bearings with a contact angle of 15°
Single bearing or bearing in pairs(7000 C.7000 C/DT)
Fa/Fr≤e Pr=Fr
Fa/Fr>e Pr=0.44Fr+YFa
Back-to-back and face to face arrangements(7000 C/DB.7000 C/DF)
Fa/Fr≤e Pr=Fr+Y1Fa
Fa/Fr>e Pr=0.72Fr+Y2Fa
Single-row angler contact ball bearings with a contact angle of 25°
Single bearing or bearing in pairs(7000 AC.7000 AC/DT)
Fa/Fr≤0.68 Pr=Fr
Fa/Fr>0.68 Pr=0.41Fr+0.87Fa
Back-to-back and face to face arrangements(7000 AC/DB.7000 AC/DF)
Fa/Fr≤0.68 Pr=Fr+0.92Fa
Fa/Fr>0.68 Pr=0.67Fr+1.41Fa
Single-row angular contact ball bearings with a contact angle of 40°
Single bearing or bearing in pairs (7000 B.7000 B/DT)
Fa/Fr≤1.14 Pr=Fr
Fa/Fr>1.14 Pr=0.35Fr+0.57Fa
Back-to-back and face to face arrangements(7000 B/DB.7000 B/DF)
Fa/Fr≤1.14 Pr=Fr+0.55Fa
Fa/Fr>1.14 Pr=0.57Fr+0.93Fa
Four point contact ball bearings with a contact angle of 35°
Fa/Fr≤0.95 Pr=Fr+0.66Fa
Fa/Fr>0.95 Pr=0.6Fr+1.07Fa
Double-row angular contact ball bearings with a contact angle of 45°
Fa/Fr≤1.34 Pr=Fr+0.47Fa
Fa/Fr>1.34 Pr=0.54Fr+0.81Fa
Static equivalent radial load
Single-row angular contact ball bearings with a contact angle of 15°
For single bearing or bearing in pairs(7000 C.7000 C/DT)
P0r=0.5Fr+0.46Fa
P0r<Fr P0r=Fr
For back-to-back and face-to-face arrangements (7000 C/DB.7000 C/DF)
P0r=Fr+0.92Fa
Single-row angular contact ball bearings with contact angle of 25°
For single bearing or bearing in pairs (7000 AC.7000 AC/DT)
P0r=0.5Fr+0.38Fa
when P0r<Fr let P0r=Fr
For two bearings in back-to-back and face-to-face arrangements
P0r=Fr+0.76Fa
Single-row angular contact ball bearings with contact angle of 40°
For single bearing or bearing in pairs
P0r=0.5Fr+0.26Fa
when P0r<Fr let P0r=Fr
For two bearings in back-to-back and face-to-face arrangements
P0r=Fr+0.52Fa
Four point contact ball bearings
P0r=Fr+0.58Fa
Double-row angular contact ball bearings with contact angle of 45°
P0r=Fr+0.44Fa
Fr Actual radial load of the bearing.
Fa Axial load of the bearing
The values of e .Y .Y1 .Y2 see Table 2.
Table 1 Axial internal clearance of four point contact ball bearings
μm
|
Nominal bore diameter d
mm
|
C2
clearance
|
Standard
clearance
|
C3
clearance
|
C4
clearance
|
|
Over
|
To
|
Min
|
Max
|
Min
|
Max
|
Over
|
To
|
Min
|
Max
|
|
10
18
40
60
80
100
140
180
220
260
|
18
40
60
80
100
140
180
200
260
300
|
15
26
36
46
56
66
76
96
115
135
|
55
66
86
96
116
136
156
176
195
215
|
45
56
76
86
96
116
136
156
175
195
|
85
106
126
136
156
176
196
216
235
275
|
75
96
116
126
135
156
176
196
215
255
|
115
146
166
176
196
216
236
256
295
335
|
105
136
156
166
176
196
216
236
275
295
|
145
186
206
216
236
256
276
296
335
355
|
Table 2 Calculate Coefficient
μm
|
|
e
|
Y
|
Y1
|
Y2
|
|
0.172
0.345
0.689
1.03
1.38
2.07
3.45
5.17
6.89
|
0.38
0.4
0.43
0.46
0.47
0.5
0.55
0.56
0.56
|
1.47
1.4
1.3
1.23
1.19
1.12
1.02
1
1
|
1.65
1.57
1.46
1.38
1.34
1.26
1.14
1.12
1.12
|
2.39
2.28
2.11
2
1.93
1.82
1.66
1.63
1.63
|
Dw is the diameter of the rolling element
Моя корзина (
Сканирование посетить
