Bearing Knowledge

▏Bearing Material

☉High carbon chromium bearing steel is the best material for bearing. It features high hardness, strong rolling fatigue resistance, abrasion resistance and stable sizes.

☉Chemical compositions of GCr15 (SAE52100) are shown on following table.

Chemical Composition %

C

0.95~1.05

Cr

1.40~1.65

Si

0.15~0.35

Mn

0.25~0.45

P

0.027

S

0.02

Chemical Composition %

Ni

0.23

Cu

0.25

Mo

0.1

Sn

0.03

As

0.04

Ti

0.005

Chemical Composition %

Sb

0.002

Pb

0.002

O

0.001

Ai

0.05

Ca

0.01



☉Stainless steel bearing parts material table:


Part Name

INNER RING

OUTER RING

BALL

CAGE

SHIELD

SEAL

Material No

AISI440B

(9Cr18Mo)

AISI440B

(9Cr18Mo)

AISI440B

(9Cr18Mo)

AISI304

AISI304(302)

NBR

AISI440C

(9Cr18)

AISI440C

(9Cr18)

AISI440C

(9Cr18)

AISI304

AISI304(302)

NBR


☉The Chemical Composition of different stainless steel number.


Stainless steel No

C%

Cr%

Si%

Mn%

S%

P%

Mo%

Ni%

AISI440B

0.90~1.00

17~19

0.8

0.8

0.3

0.035



AISI440C

0.95~1.10

16~18

0.8

0.8

0.3

0.035

0.4~0.7


AISI304

0.07

17~19

1

2

0.3

0.035


8~11

▏Tolerance

Bearing tolerance refers to the size accuracy and running accuracy. The different international standard accuracy as below:


Standard code

Precision class

CHINA GB

0

6

5

4

2

ISO

0

6

5

4

2

ANSI

ABEC-1

ABEC-3

ABEC-5

ABEC-7

ABEC-9

SKF

P0

P6

P5

P4

P2

DIN

P0

P6

P5

P4

P2

JIS

0

6

5

4

2