AKA SKATE BEARINGS CO.,LIMITED

Contact Us

Tel: +86-510-83231690
Fax: +86-510-83231699
E-mail: info@skate-bearings.com
Add: No.2,Jinshanbei Industry Zone,Wuxi City,214000,JiangSu,China
info@skate-bearings.com

Technology
  

Structure of bearing

Single-row deep groove ball bearings are the most common type of rolling bearing, having a wide range of suitable applications. The raceway grooves on both inner and outer rings have circular arcs of slightly larger radius than that of the balls. In addition to radial loads, axial loads can be applied in either direction. Because of their low torque, they offer high speed operation with low power loss.

COMPONENT INDENTIFICATION
BEARING TYPES
Standard Open
 
 
Standard Shielded
 
 
Flanged Open
Flanged Shielded


Bearing Material

RINGS & BALLS vacuum degassed, high carbon chromium bearing steel GCr15 is the standard material for precision bearing rings and balls. The material has uniform specification as AISL 52100(America)DIN100 Cr6(German),JISSUJ2(Japan)

Steel No.

Chemical composition %

C

Si

Min

P

S

Cr

Mo

Cu

Ni

GCr 15

0.95-1.05

0.15-0.35

0.25-0.45

s0.025

s0.025

1.40-1.65

-

s0.25

s0.30

STAINLESS STEEL

Specification

Trademark

Chemical composition (%)

C

Si

Mn

P

S

Cr

Mo

GB 3086

9Cr18

0.90-1.00

Below 0.80

Below 0.80

Below 0.35

Below 0.30

17.00-19.00

 

JIS G 4303

SUW440C

0.95-1.20

Below 1.00

Below 1.00

Below 0.40

Below 0.30

16.00-18.00

Below 0.75

RETAINERS-LB standard bearing retainers are made from cold rolled carbon steel however, in cases of corrosive environment, misalignment,or high speed operation, stainless steel, or phenolic resins will be used upon request.


1.CROWN RETAINER: The standard metal crown retainer is very light weight, with specially coined ball pockets to reduce torque and provide smooth running characteristics. Material used is 400 series stainless steel.


2.RIBBON RETAINER: The closed pocket design of the ribbon retainer is the most common type. The material used is 300 series stainless steel. For low torque applications, a loose clinched ribbon retainer may be available.


3.PHENOLICRETAINER: Plastic crown retainers have the highest speed ratings of any standard retainer type, but have limited availability.



Accuracy

There are stipulations to the roller bearing major size allowable tolerance, admittance value, rotating precision in the National Standard of GB3.7.1. the following is a comparison table between these admissions and ISO, JIS Standards:

Standard allowable tolerance grades
GB\T307.1
PO
P6
P5
P4
P2
ISO 492
Normal Class
Class6
Class5
Class4
Class2
JIS B 1514
JIS 0 Grade
JIS 6 Grade
JIS 5 Grade
JIS 4 Grade
JIS 2 Grade
AFBMA STD.20
ABEC 1
ABEC 3
ABEC 5
ABEC7
ABEC9


Lubrication

LUBRICATION

SRS bearings, single or double shielded (Z, ZZ) and single or double sealed (RS, 2RS). Before the formal shipment, we fill into the qualified oil or grease strictly. If you have any special requests about the lubrication, please feel free to show us and we can fill the corresponding oil or grease with the accurate rate as per your special requests. Below the following is our normal grease.

Manufacturer

Brand name

Basic type grease

Operation temp.c

Use

Exxon

 Beacon 325 

synthetic grease  

-55~120

General purpose grease

Exxon 

 Andok B(Mil-G-18709A)

Channeling petroleum grease

-30~95 

Excellent high speed,low torque,light mass

Exxon

 Andok C  

 Channeling petroleum grease

-30~120

Smooth running,long life

 G.E.Versilube G300

 

Silicone gorase

-75~205

Lighe loads and fine moderate speed

Mobil28

 (Mil-G-81332)

Synthetic hydrocarbon

-55~180

Wide temperature range,good low temperature torque

Chevron

 

Mineral grease

-30~180

High temperature range with good water resistance

Shell

 Alvania2

Mineral grease

-35~120

Long life and wide application

DuPont

 Krytox 240AC(mil-G-27617)

Fluorinated grease

-35~290

High temperature stablility with good lubricity properties

Shell

 Dolium R

Petroleum grease

-40~150

Good corrosion resistance and water resistance

KYODO

SRL

Synthetic grease

-40~150

Low noise,low torque and special case

NIG-ACE

W

Synthetic grease

-18~150

Low noise,low torque and special case

Mobil

HP

Lithium complex

-30~110

 Vibration,moderate speeds and good corrosion resistance

Tianjin Hangu

Motor No.2

Mineral grease

-30~110

wide application,general purpose



Vibration and noise

The vibration and noise of bearings are classified as four classed as Z1,Z2,Z3 and Z4.It is measured by the instrument of S0910-1,For special requirement,it is measured by BVT-1 and classified as V1, V2, V3 and V4.The data are shown as below. Customer need mark their requirement of vibration and noise class on the order.

Tolerance data for vibration of single bearing   Tolerance in um/s
d

mm
V
V1
V2
V3
V4
Low
Brand
Medium
Brand
High
Brand
Low
Brand
Medium
Brand
High
Brand
Low
Brand
Medium
Brand
High
Brand
Low
Brand
Medium
Brand
High
Brand
Low
Brand
Medium
Brand
High
Brand
3,4
80
44
44
60
35
32
48
26
22
31
16
15
28
10
10
5,6
110
72
60
74
48
40
58
36
30
35
21
18
32
11
11
7,8,9
130
96
80
92
66
54
72
48
40
44
28
24
38
12
12
10,12
160
120
100
120
80
70
90
60
50
55
35
30
45
14
15
15
210
150
120
150
100
85
110
78
60
65
46
35
52
18
18
17
210
150
120
150
100
85
110
78
60
65
46
35
52
25
25
20
260
190
150
180
125
100
130
100
75
80
60
45
60
25
25
22,25
260
190
150
180
125
100
130
100
75
80
60
45
60
30
32
28
260
190
150
180
125
100
130
100
75
80
60
45
60
35
40
30,32
300
240
190
200
150
130
150
120
100
90
75
60
70
35
40
35
300
240
190
200
150
130
150
120
100
90
75
60
70
42
45
40
360
300
260
240
180
160
180
150
130
110
90
80
82
50
50
45
360
300
260
240
180
160
180
150
130
110
90
80
82
60
60
50
420
320
320
280
200
200
210
160
160
125
100
100
95
70
70
Maximum vibration acceleration of single bearing   Tolerance in dB
d
mm
Diameter Series(0)
Diameter Series(2)
Diameter Series(3)
Z
Z1
Z2
Z3
Z
Z1
Z2
Z3
Z4
Z
Z1
Z2
Z3
Z4
3
35
34
32
28
36
35
32
30
_
37
36
33
31
_
4
35
34
32
28
36
35
32
30
_
37
36
33
31
_
5
37
36
34
30
38
37
34
32
_
39
37
35
33
_
6
37
36
34
30
38
37
34
32
_
39
37
35
33
_
7
39
38
35
31
40
38
36
34
_
_
_
_
_
_
8
39
38
35
31
40
38
36
34
_
_
_
_
_
_
9
41
40
36
32
42
40
37
35
_
_
_
_
_
_
10
43
42
38
33
44
42
39
35
30
37
44
40
37
32
12
44
43
39
34
45
43
39
35
30
47
45
40
37
32
15
45
44
40
35
46
44
41
36
31
48
46
42
38
33
17
46
44
40
35
47
45
41
36
31
49
47
42
38
33
20
47
45
41
36
48
46
42
38
33
50
48
43
39
34
22
47
45
41
36
48
46
42
38
33
50
48
43
39
34
25
48
46
42
38
49
47
43
40
36
51
49
44
41
37
28
49
47
43
39
50
48
44
41
37
52
50
45
42
38
30
49
47
43
39
50
48
44
41
37
52
50
45
42
38
32
50
48
44
40
51
49
45
42
38
53
51
46
43
39
35
51
49
45
41
52
50
46
43
39
54
52
47
44
40
40
53
51
46
42
54
52
47
44
40
56
54
49
45
41
45
55
53
48
45
56
54
49
46
43
58
56
51
47
44
50
57
54
50
47
58
55
51
48
45
60
57
53
49
46
55
59
56
52
49
60
57
53
50
47
62
59
54
51
48
60
61
58
54
51
62
59
54
51
48
64
61
56
53
50


Internal clearance

Clearance is gap amid bearing inner ring, outer ring, ball package. Bearing has radial clearance and axial clearance.

Deep-groove ball bearing radial clearance

Nominal bearing
inner diameter
d(mm)

Clearance

C2

CN

C3

C4

C5

Exceed

Below

Min.

Max.

Min.

Max.

Min.

Max.

Min.

Max.

Min.

Max.

10
(Be limited to)

-

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

20

5

13

25

20

36

25

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

40

50

1

11

6

23

18

36

30

51

45

73

50

65

1

15

8

28

23

43

38

61

55

60

65

80

1

15

10

30

25

51

46

71

65

105

80

100

1

18

12

36

30

58

53

84

75

120

Miniature Bearing's Internal Radial Clearance

Clearance mark

MC1

MC2

MC3

MC4

MC5

MC6

Clearance

max

min

max

min

max

min

max

min

max

min

max

min

0

5

3

8

5

10

8

13

13

20

20

28



Points of attention for using

Roller bearing is a precise part. Therefore it should be used carefully. No matter how high performance the bearing is, it can not be obtained by improper use. The followings are the points for attention of use to the bearings.
(1) Keep clean the bearing and its surrounding areas
It is harmful to the bearing even by tiny dust which can not be seen by human eyes. Therefore it should always keep clean the surrounding environments in order to prevent the bearing from dust corrosion.
(2) Cautious use of the bearing
Scar or indentation can easily be produced out of strong impact to the bearing in use and become the cause of accidents. It will even be cracked or broken in severe occasions.
Therefore special caution should be given to its use.
(3) Use the appropriate operating tool
It is forbidden to use the current tool in operation. Proper and appropriate tool should be adopted then.
(4) Be careful to the rust corrosion of the bearings
The sweat in the hands will cause rust in operating the bearings. Therefore your hands should be cleanly washed and dried before operation. You'd better wear gloves in doing the work.

Installation

The bearing installation has close relationships with the accuracy, life and performance.  Therefore the design and assembly departments should fully research into the bearing installation.
It is better to implement installation according to the operation standard. The items of the operation standard are usually as follows:
(1) Clean bearing and its related parts
(2) Check the size and finishing conditions of the related parts
(3) Installation
(4) Examine bearings after installation
(5) Feed the lubricant
The bearing packing should be opened shortly before installation. There is no need for cleaning to ordinary lubricating grease lubrication, direct-filling of lubricating grease or lubricating oil. Whereas it should use the clean oil to rinse the instrument purpose bearing or high speed purpose bearing etc. and get rid of the anti-rusting agent on the bearing. The bearing easily gets rusty without rust inhibitor. Therefore special care should be taken to such kind of the bearing.
What is more, the bearing which has been sealed with lubricating grease can be put into direct use with no cleaning at all.
The installation methods of the bearing vary according to the difference in the bearing structure, matching, condition. As it is mostly of axle rotation, the inner ring needs interference fit. The cylindrical bore bearing is commonly pressed in by pressing machine or most probably, it adopts the heat installation method. The taper hole can be directly
installed in the taper axle or by sleeving.

 

Inspection and Test

In the whole course from purchasing of raw materials to every process of production, “SRS”Brand bearings are all strictly and carefully inspected to guarantee quality.Besides the basic and normally used testing instruments,the company also adopts the following testing and inspecting instruments to control the production processes and finished products.

No. Model No.of instrument
Name of instrument Test item

(1): HV-4B Pc high-speed automatic carbon and sulfur analyser Chemical composition of raw material
(2): HC-II High-speed digital display automatic analyzer
(3): 4X1 Metallurgical microscope Analysis of material and metallurgical structure
(4): Y9025 Roundness measuring equipment Roundness of groove and outer diameter
(5): R902 Groove curvature inspecting instrument Groove curvature and groove shape
(6): SRM-1 Surface roughness inspecting instrument Roughness of groove and surface
(7): S0910 Bearing vibration inspecting instrument (Accelerationg)vibration and abnormal sound
(8): BVY-1 Bearing vibration inspecting instrument (speed) vibration and abnormal sound