 |
bearing clearance
¡¡¡¡The radial clearance of bearings might be divided into five groups
according to ISO 5753. The radial clearance without preload is shown
on the table. Normally, the products are assembled as basic group
clearance. Please note the special requirement in your order sheet
if any customer needs bearing clearance rather than the value of basic
group. |
| Deep groove ball bearing clearance |
|
Bore diameter(mm)
|
Group 2(C2)
|
Normal group(0)
|
Group 3(C3)
|
Group 4(C4)
|
Group 5(C5)
|
|
Over
|
To
|
Min
|
Max
|
Min
|
Max
|
Min
|
Max
|
Min
|
Max
|
Min
|
Max
|
|
2.5
|
6
|
0
|
7
|
2
|
13
|
8
|
23
|
14
|
29
|
20
|
37
|
|
6
|
10
|
0
|
7
|
2
|
13
|
8
|
23
|
14
|
29
|
20
|
37
|
|
10
|
18
|
0
|
9
|
3
|
18
|
11
|
25
|
18
|
33
|
25
|
45
|
|
18
|
24
|
0
|
10
|
5
|
20
|
13
|
28
|
20
|
36
|
28
|
48
|
|
24
|
30
|
1
|
11
|
5
|
20
|
13
|
28
|
23
|
41
|
30
|
53
|
|
30
|
40
|
1
|
11
|
6
|
20
|
15
|
33
|
28
|
46
|
40
|
64
|
|
Bearing accuracy
¡¡¡¡Bearing accuracy refers to accuracy on dimension and rotation. According
to Chinese national standard, the bearing accuracy is divided into
five classes: Class 0, Class6, Class 5, Class 4 and Class 2. All of
them are adopt to ISO standard. The comparison of different accuracy
classes are equivalent as follows: |
Comparison Table of Accuracy Grade
|
standard code
|
Accuracy Grade
|
|
GB
|
0
|
6
|
5
|
4
|
2
|
|
ISO
|
0
|
6
|
5
|
4
|
2
|
|
ANSI
|
ABEC1
|
ABEC3
|
ABEC5
|
ABEC7
|
ABEC9
|
|
SKF
|
P0
|
P6
|
P5
|
P4
|
P2
|
|
DIN
|
P0
|
P6
|
P5
|
P4
|
P2
|
|
JIS
|
0
|
6
|
5
|
4
|
2
|
|
|
Bearing collar and roller material
The best material for rolling bearing is high carbon chromium bearing
steel, which features desired hardness, resist to fatigue, wear
resistance andstable dimension. Its chemical composition is£º
|
| Chemical composition of bearing steel GCr15 |
|
element content(wt)%
|
C 0.95-1.05
|
Cr1.40-1.65
|
Si0.15-0.35 |
Mn0.25-0.45 |
P¡Ü0.027
|
S¡Ü0.02
|
|
element content(wt)%
|
NI<0.23
|
Cu¡Ü0.25
|
Mo¡Ü0.1
|
Sn<0.03
|
As<0.04
|
Ti<0.005
|
|
element content(wt)%
|
Sb<0.002
|
Pb<0.002
|
O<0.001
|
A1<0.05
|
Ca<0.01
|
0
|
|
| Bearing vibration noise specification According to related standard,
the vibration noise (dB) of bearings for their vibration under acceleration
are divided into four groups: Z1,Z2, Z3 and Z4.Also they can be divided
into four groups in according to vibration speed(¦Ìm/s): V1, V2, V3,
and V4. |
|
 |
