Angular Contact Ball Bearing

        Single row angular contact ball bearings can not only withstand radial load and axial load in one direction, but also accommodate only axial load in single direction, radial loads produce axial forces in these bearings that need to be balanced by counter forces.Therefore, the single row angular contact ball bearings often need to be installed with other bearings which withstand axial load in the opposite direction. In other words, the angular contact ball bearings are commonly used in pair, or in groups with three, four and even five bearings. Angular contact ball bearings have higher limiting speed.


The bearings codes designation:

555.png 

 

The bearings matched ways as below :

1574738527107794.png 

777.png 

DB

The load lines in a pair of bearings by back to back assembly are enlarging from the bearing axis. It can bear axial load in two directions and relative larger moment because of larger angular rigidity.

 

DF

The load lines in a pair of bearings by face to face assembly are convergence toward the bearing axis. It can bear axial load in two directions and smaller moment because of smaller angular rigidity.

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999.png 

DT

A pair of bearings by series a ssembly only bear axial load in one direction, but it is able to

 bear larger axial load related to DB and DF.


TBT

The tri-bearing matching TBT or TFT isobtained by increasing the same type of the bearing based on DB or DF There are higher axial and radial rigidity for TBT and TFT, so larger load can be supported.

1574738615965590.png 

121212.png 

QBC

The four bearing matching QBC (or QFC) is obtained by matching double set of DB (or DF) bearings. QBT (or QFT) is formed when three bearings are installed in a same direction and another one back (or face) to them.

PBC

Divide the five bearings into two groups of three and two bearings respectively, in which the bearings are all installed in the same direction, PBC is formed when the groups match each other by back to back and PFC by face to face. If four bearings are installed in the same direction and another one back (or face) to them, then PBT (or PFT) is formed.



 

1.MONTON Angular contact ball bearings performance and Characteristics.

 

 

The MONTON precision angular contact ball bearings for spindle, have four size series, 718,719,70 and 72. With the same inner diameter, but the outer diameter and the width of 718,719,70 and 72 series increase in turn.

 

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                     Fig.1  Angular contact ball bearing dimension series

MONTON precision angular contact ball bearings with 15° (C) and 25° (AC) contact angles. As for the angular contact ball bearings, the bigger the contact angle is, the greater the axial load capacity is, but the lower the limiting speed of bearings becomes. Therefore, the spindle, with high speed and small axial load, should adopt the 15° angular contact ball bearings, whereas the 25° angular contact ball bearings should be adopted. 

MONTON precision angular contact ball bearings with high-speed angular contact bearings (standard series), super high-speed angular contact ball bearings, high-speed sealed angular contact ball bearings and high-speed spindle bearings.

 

The inner ring, outer ring and rolling element of rolling bearing under normal operating conditions are made of high carbon chromium bearing steel, but the steel bearings cannot meet the requirements of such special conditions as high speed, wear-resisting, low temperature rising, long life and high reliability etc., then Si3N4 ceramics are believed to be present optimum rolling bearing materials to replace bearing steel.

 


Table 1. Main performance comparison between Si3N4 and bearing steel

Performance

Code and unit

Si3N4

Bearing steel

Density

γ[g/mm3]

3.2

7.8

Coefficient of thermal expansion

α[1/]

201000

3.2×10-6

-

20300

-

11.8×10-6

Modulus of elasticity

E[N/mm2]

3.15×105

2.08×105

Poisson's ratio

μ

0.26

0.3

Rigidity

HV10

1700

700

Stress  intensity

σB[N/mm2]

20

700

2400

1000

700

0

Fracture toughness

Kie[MN/m1.5]

7

25

Coefficient of heat conductivity

λ[W/m]

3040

4050

Electrical resistivity

[Ωmm2/m]

10171018

0.11

MONTON also offers widely used hybrid angular contact ball bearings for spindles in high-speed precision machine tools and other high-speed precision machines, that is, the inner and outer rings are made of high-quality bearing steel materials, while the rolling element is made of Si3N4 ceramics. 

Compared to the angular contact ball bearings made of steel, hybrid angular contact ball bearings with the same structure and size have high speed, high stiffness, low friction heat, and long life etc.

MONTON precision hybrid bearings with ceramic ball (HQ1) can significantly improve the speed, rigidity, reliability, and productivity of machine tools, and greatly reduce the friction heat, then extend the service life of host machine etc.

 

 

Table 2. The type and performance of MONTON angular contact ball bearing

MONTON angular contact ball bearing series

Structures

Dimension series

Bore size range

Performance

High precision angular contact ball bearing

718 C

718 AC

719 C

719 AC

70 C

70 AC

72 C

72 AC

71810360mm

7198460mm

708380mm

728220mm

High speed

Large loading capacity

Suit for grease

or oil-mist lubrication

 

High speed angular contact ball bearing

(hybrid ball bearing)

H719 C

H719 AC

H70 C

H70 AC

H719 C/HQ1

H719 AC/HQ

H70 C/HQ1

H70 AC/HQ1

H7198220mm

H708220mm

H719/HQ18220mm

H70/HQ18220mm

Super speed

High rigidity

Suit for air-oil or oil injection lubrication

 

Super speed angular contact ball bearing(

incl.

hybrid ball bearing)

HS719 C

HS719 AC

HS70 C

HS70 AC

HS719 C/HQ1

HS719 AC/HQ

HS70 C/HQ1

HS70 AC/HQ1

HS7198220mm

HS708220mm

HS719/HQ1:8220mm

HS70/HQ1:8220mm

Super speed

(higher than H series)

High rigidity

Suit for air-oil or oil injection lubrication

Super speed angular contact ball bearing with direct lubrication(incl. hybrid ball bearing)

H719 C-DL

H719 AC-DL

H70 C-DL

H70 AC-DL

H719 C/HQ1-DL

H719 AC/HQ-DL

H70 C/HQ1-DL

H70 AC/HQ1-DL

H719-DL20220mm

H70-DL30220mm

H719/HQ1-DL20220mm

H70/HQ1-DL30220mm

 

Super speed (higher than H and HS series)

High rigidity

.Suit for direct lubrication  

High speed sealed angular contact ball bearing

(incl. hybrid ball bearing)

B719 C-2RZ

B719 AC-2RZ

B70 C-2RZ

B70 AC-2RZ

B70 C-2RZ/HQ1

B719 AC-2RZ/HQ1

B70 C-2RZ/HQ1

B70 AC-2RZ/HQ1

B719-2RZ10220mm

B70-2RZ10220mm

B719-2RZ/HQ1:1220mm

B70-2RZ/HQ110220mm

 

High speed

High rigidity

Grease lubrication

 

2.The principles of selecting precision bearings

MONTON has developed and produced various kinds and structures of high-speed precision bearings, each of which has special working conditions. Selecting different types and structures should depend on specific working conditions. When choosing bearings, the following properties should be taken into consideration.

2.1 Dimension series

Among MONTON precision bearings, angular contact ball bearings have four diameter series 18,19, (1) 0, (0) 2; the ball screw support bearings have two diameter series, (0) 2, (0) 3. With the bore diameters in the same size, the outer diameters and width dimensions of 18,19, (1) 0, (0) 2, (0) 3 series increase in turn.

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   Fig. 13 The comparison of each dimension series between angular contact ball bearings and ball screw support bearings

The (1) 0 diameter series bearings are most usually used among angular contact ball bearings, cylindrical roller bearings, double direction angular contact thrust ball bearings and tapered roller bearings for high-speed precision machine spindle.

As for the angular contact ball bearings, if the radial space in mounting position is limited or the required speed of spindle is higher, (1) 0 or 19 diameter series are recommended, and even 18 diameter series; if spindle supports large load, speed is not quite high and mounting space is not limited, the (0) 2 diameter series are preferred.

 

the greater the axis diameter of spindle is, the higher the rigidity becomes. To improve the bearing rigidity is to increase the number of balls, which is more favorable than increasing the ball diameter.

 

 

3. Bearing precision

MONTON can supply the P5,P4,P2 accuracy angular contact ball bearings.

Here below is the list for the different accuracy:

 

 

Table 4. Tolerances for the inner ring of angular contact ball bearing in P5 (μm)

d

mm

dmp

Vdp(1)

Vdmp

Kia

Sd

Sia

Bs

VBS

Diameter series

9

02

All

Normal

Revise

 

From

 

to

 

Upper deviation

 

Lower deviation

max

max

max

max

max

Upper deviation

Lower

deviation

max

2.5

10

18

30

50

80

120

180

10

18

30

50

80

120

180

250

0

0

0

0

0

0

0

0

-5

-5

-6

-8

-9

-10

-13

-15

5

5

6

8

9

10

13

15

4

4

5

6

7

8

10

12

3

3

3

4

5

5

7

8

4

4

4

5

5

6

8

10

7

7

8

8

8

9

10

11

7

7

8

8

8

9

10

13

0

0

0

0

0

0

0

0

-40

-80

-120

-120

-150

-200

-250

-300

-250

-250

-250

-250

-250

-380

-380

-500

5

5

5

5

6

7

8

10

 


Table 5. Tolerances for the outer ring of angular contact ball bearing in P5(μm)

D

mm

Dmp

VDp(1)(2)

VDmp

Kea

SD

Sea

Cs

VCS

 Diameter series

9

02

From

to

Upper deviation

Lower deviation

max

max

max

max

max

Upper deviation

Lower deviation

max

6

18

30

50

80

120

150

180

250

315

18

30

50

80

120

150

180

250

315

400

0

0

0

0

0

0

0

0

0

0

-5

-6

-7

-9

-10

-11

-13

-15

-18

-20

5

6

7

9

10

11

13

15

18

20

4

5

5

7

8

8

10

11

14

15

3

3

4

5

5

6

7

8

9

10

5

6

7

8

10

11

13

15

18

20

8

8

8

8

9

10

10

11

13

13

8

8

8

10

11

13

14

15

18

20

Width   deviation Cs is identical with Bs of the corresponding inner ring.

5

5

5

6

8

8

8

10

11

13

 


Table 6. Tolerances for the inner ring of angular contact ball bearing in P4(μm)

 

d

mm

dmp

ds(1)

Vdp(2)

Vdmp

Kia

Sd

Sia

Bs

VBS

 Diameter series

9

02

All

Normal

Revise

 From

 to

Upper deviation

Lower deviation

Upper deviation

Lower deviation

max

max

max

max

max

 

Upper deviation

 

Lower

deviation

max

2.5

10

18

30

50

80

120

180

10

18

30

50

80

120

180

250

0

0

0

0

0

0

0

0

-4

-4

-5

-6

-7

-8

-10

-12

0

0

0

0

0

0

0

0

-4

-4

-5

-6

-7

-8

-10

-12

4

4

5

6

7

8

10

12

3

3

4

5

5

6

8

9

2

2

2.5

3

3.5

4

5

6

2.5

2.5

3

4

4

5

6

8

3

3

4

4

5

5

6

7

3

3

4

4

5

5

7

8

0

0

0

0

0

0

0

0

-40

-80

-120

-120

-150

-200

-250

-300

-250

-250

-250

-250

-250

-380

-380

-500

2.5

2.5

2.5

3

4

4

5

6

 

 

Table 7. Tolerances for the outer ring of angular contact ball bearing in P4(μm) 

D

mm

Dmp

Ds(1)(2)(3)

VDp(2)(3)

VDmp

Kea

SD

Sea

Cs

VCS

Diameter series

9

02

From

 to

Upper deviation

Lower deviation

Upper deviation

Lower deviation

max

max

max

max

max

Upper deviation

Lower deviation

max

6

18

30

50

80

120

150

180

250

315

18

30

50

80

120

150

180

250

315

400

0

0

0

0

0

0

0

0

0

0

-4

-5

-6

-7

-8

-9

-10

-11

-13

-15

0

0

0

0

0

0

0

0

0

0

-4

-5

-6

-7

-8

-9

-10

-11

-13

-15

4

5

6

7

8

9

10

11

13

15

3

4

5

5

6

7

8

8

10

11

2

2.5

3

3.5

4

5

5

6

7

8

3

4

5

5

6

7

8

10

11

13

4

4

4

4

5

5

5

7

8

10

5

5

5

5

6

7

8

10

10

13

Width   deviation Cs is identical with Bs of the corresponding inner ring.

2.5

2.5

2.5

3

4

5

5

7

7

8

 



Table 8. Tolerances for the inner ring of angular contact ball bearing in P4A(μm) 

d

mm

dmp

ds(1)

Vdp(2)

Vdmp

Kia

Sd

Sia

Bs

VBS

 All

Normal

Revise

 From

 to

Upper deviation

Lower deviation

Upper deviation

Lower deviation

max

max

max

max

max

Upper deviation

Lower

deviation

max

2.5

10

18

30

50

80

120

150

180

10

18

30

50

80

120

150

180

250

0

0

0

0

0

0

0

0

0

-4

-4

-5

-6

-7

-8

-10

-10

-12

0

0

0

0

0

0

0

0

0

-4

-4

-5

-6

-7

-8

-10

-10

-12

2.5

2.5

2.5

2.5

4

5

7

7

8

1.5

1.5

1.5

1.5

2

2.5

3.5

3.5

4

1.5

1.5

2.5

2.5

2.5

2.5

2.5

5

5

1.5

1.5

1.5

1.5

1.5

2.5

2.5

4

5

1.5

1.5

2.5

2.5

2.5

2.5

2.5

5

5

0

0

0

0

0

0

0

0

0

-40

-80

-120

-120

-150

-200

-250

-250

-300

-250

-250

-250

-250

-250

-380

-380

-380

-500

1.5

1.5

1.5

1.5

1.5

2.5

2.5

4

5

 

Table 9. Tolerances for the outer ring of angular contact ball bearing in P4A(μm)

 

D

mm

Dmp

Ds(1)(2)(3)

VDp

VDmp

Kea

SD

Sea

Cs

VCS

From

to

Upper deviation

Lower deviation

Upper deviation

Lower deviation

max

max

max

max

max

Upper deviation

Lower deviation

max

6

18

30

50

80

120

150

180

250

315

18

30

50

80

120

150

180

250

315

400

0

0

0

0

0

0

0

0

0

0

-4

-5

-6

-7

-8

-9

-10

-11

-13

-15

0

0

0

0

0

0

0

0

0

0

-4

-5

-6

-7

-8

-9

-10

-11

-13

-15

2.5

4

4

4

5

5

7

8

8

10

1.5

2

2

2

2.5

2.5

3.5

4

4

5

1.5

2.5

2.5

4

5

5

5

7

7

8

1.5

1.5

1.5

1.5

2.5

2.5

2.5

4

5

7

1.5

2.5

2.5

4

5

5

5

7

7

8

Width   deviation Cs is identical with Bs of the corresponding inner ring.

1.5

1.5

1.5

1.5

2.5

2.5

2.5

4

5

7

 

 

 Table 10. Tolerances for the inner ring of angular contact ball bearing in P2(μm) 

d

mm

dmp

ds

Vdp(1)

Vdmp

Kia

Sd

Sia

Bs

VBS

 All

Normal

Revise

 From

to

Upper deviation

Lower deviation

Upper deviation

Lower deviation

max

max

max

max

max

Upper deviation

Lower

 deviation

max

2.5

10

18

30

50

80

120

150

180

10

18

30

50

80

120

150

180

250

0

0

0

0

0

0

0

0

0

-2.5

-2.5

-2.5

-2.5

-4

-5

-7

-7

-8

0

0

0

0

0

0

0

0

0

-2.5

-2.5

-2.5

-2.5

-4

-5

-7

-7

-8

2.5

2.5

2.5

2.5

4

5

7

7

8

1.5

1.5

1.5

1.5

2

2.5

3.5

3.5

4

1.5

1.5

2.5

2.5

2.5

2.5

2.5

5

5

1.5

1.5

1.5

1.5

1.5

2.5

2.5

4

5

1.5

1.5

2.5

2.5

2.5

2.5

2.5

5

5

0

0

0

0

0

0

0

0

0

-40

-80

-120

-120

-150

-200

-250

-250

-300

-250

-250

-250

-250

-250

-380

-380

-380

-500

1.5

1.5

1.5

1.5

1.5

2.5

2.5

4

5

 

Table 11. Tolerances for the outer ring of angular contact ball bearing in P2(μm)

D

mm

Dmp

Ds

VDp

VDmp

Kea

SD

Sea

Cs

VCS

From

to

Upper deviation

Lower deviation

Upper deviation

Lower deviation

max

max

max

max

max

Upper deviation

Lower deviation

max

6

18

30

50

80

120

150

180

250

315

18

30

50

80

120

150

180

250

315

400

0

0

0

0

0

0

0

0

0

0

-2.5

-4

-4

-4

-5

-5

-7

-8

-8

-10

0

0

0

0

0

0

0

0

0

0

-2.5

-4

-4

-4

-5

-5

-7

-8

-8

-10

2.5

4

4

4

5

5

7

8

8

10

1.5

2

2

2

2.5

2.5

3.5

4

4

5

1.5

2.5

2.5

4

5

5

5

7

7

8

1.5

1.5

1.5

1.5

2.5

2.5

2.5

4

5

7

1.5

2.5

2.5

4

5

5

5

7

7

8

Width   deviation Cs is identical with Bs of the corresponding inner ring.

1.5

1.5

1.5

1.5

2.5

2.5

2.5

4

5

7

 


Table 28. Tolerances for inner ring of ball screw support bearings in P4(μm) 

d

mm

dmp

ds

Vdp

Vdmp

Kia

Sd

Sia

Bs

VBS

 All

Normal

Revise

 From

 to

Upper deviation

Lower deviation

Upper deviation

Lower deviation

max

max

max

max

max

Upper deviation

Lower

 deviation

max

10

18

30

50

80

120

18

30

50

80

120

150

0

0

0

0

0

0

-4

-5

-6

-7

-8

-10

0

0

0

0

0

0

-4

-5

-6

-7

-8

-10

3

4

5

5

6

8

2

2.5

3

3.5

4

5

2.5

3

4

4

5

6

3

4

4

5

5

6

2

2

2

3

3

4

0

0

0

0

0

0

-80

-120

-120

-150

-200

-250

-250

-250

-250

-250

-380

-380

2.5

2.5

3

4

4

5



Table 29. Tolerances for outer ring of ball screw support bearings in P4(μm)

D

mm

Dmp

Ds

VDp

VDmp

Kea

SD

Sea

Cs

VCS

 From

to

Upper deviation

Lower deviation

Upper deviation

Lower deviation

max

max

max

max

max

Upper deviation

Lower deviation

max

18

30

50

80

120

150

180

250

30

50

80

120

150

180

250

315

0

0

0

0

0

0

0

0

-5

-6

-7

-8

-9

-10

-11

-13

0

0

0

0

0

0

0

0

-5

-6

-7

-8

-9

-10

-11

-13

4

5

5

6

7

8

8

10

2.5

3

3.5

4

5

5

6

7

4

5

5

6

7

8

10

11

4

4

4

5

5

5

7

8

2

2

3

3

4

4

4

5

Width   deviation Cs is identical with Bs of the corresponding inner ring.

2.5

2.5

3

4

5

5

7

7

 



Table 30. Tolerances for inner ring of ball screw support bearings in P2(μm)

 

d

mm

dmp

ds

Vdp

Vdmp

Kia

Sd

Sia

Bs

VBS

 All

Normal

Revise

From

 to

Upper deviation

Lower deviation

Upper deviation

Lower deviation

max

max

max

max

max

Upper deviation

Lower

deviation

max

10

18

30

50

80

120

18

30

50

80

120

150

0

0

0

0

0

0

-2.5

-2.5

-2.5

4

5

7

0

0

0

0

0

0

-2.5

-2.5

-2.5

4

5

7

2.5

2.5

2.5

4

5

7

1.5

1.5

1.5

2

2.5

3.5

1.5

2.5

2.5

2.5

2.5

2.5

1.5

1.5

1.5

1.5

2.5

2.5

2

2

2

3

3

4

0

0

0

0

0

0

-80

-120

-120

-150

-200

-250

-250

-250

-250

-250

-380

-380

1.5

1.5

1.5

1.5

2.5

2.5

 

 

Table 31. Tolerances for outer ring of ball screw support bearings in P2(μm)

 

D

mm

Dmp

Ds

VDp

VDmp

Kea

SD

Sea

Cs

VCS

From

 to

Upper deviation

Lower deviation

Upper deviation

Lower deviation

max

max

max

max

max

Upper deviation

Lower deviation

max

18

30

50

80

120

150

180

250

30

50

80

120

150

180

250

315

0

0

0

0

0

0

0

0

-4

-4

-4

-5

-5

-7

-8

-8

0

0

0

0

0

0

0

0

-4

-4

-4

-5

-5

-7

-8

-8

4

4

4

5

5

7

8

8

2

2

2

2.5

2.5

3.5

4

4

2.5

2.5

4

5

5

5

7

7

1.5

1.5

1.5

2.5

2.5

2.5

4

5

2

2

3

3

4

4

4

5

Width   deviation Cs is identical with Bs of the corresponding inner ring.

1.5

1.5

1.5

2.5

2.5

2.5

4

5

 

4.The limiting speed

The limiting speed of angular contact ball bearing is the highest in all rolling bearings under the same condition. 

The limiting speed of rolling bearing depends on the structural types, dimensional series, dimensional sizes, cage materials and structures, bearing precision, internal clearance, preload, external load, lubrication methods and conditions, allowable working temperature, cooling measures, the precisions of fitting shaft and housing, etc. The limiting speeds in the condition of grease lubrication and oil (oil gas or oil mist) lubrication, listed in the sample, are only for reference. The speed values are appropriate for the following conditions:

 

(1)Bearing precision: The precision of angular contact ball bearings and ball screw support bearings is in P4 level, the precision of cylindrical roller bearings and double direction angular contact thrust ball bearings is in SP level, the precision of tapered roller bearings is in P5 level.

(2)It's used for single bearing with light preload.

(3)The bearing should be assembled regularly with shaft and housing with appropriate fitting, running the bearing parts is to keep a dynamic balance.

(4)The lubricating grease, with high quality and suitable for precision bearing, is adopted to grease lubrication with appropriate amount of grease.

(5)The lubricating oil keeps excellent performance, suitable viscosity and sufficient amount of oil.

(6)The preload of bearings can not be excessive with bearing running at the normal working temperature.

 

The limiting speeds value given in the catalogue are the maximum speeds under ideal conditions, while the actual speeds are generally lower than the given value according to the variety of conditions.

 

The limiting speeds of matched bearing are determined by matching methods, preload level, and bearing precision level. The limiting speeds will be reduced with the reduction coefficient in the Table 32.

 

Table 32. The reduction coefficient of limiting speed

Matched methods

Preload level

Tolerance class

2

4

5

DT

A

0.99

0.9

0.81

B

0.88

0.8

0.72

C

0.7

0.65

0.58

DB

A

0.88

0.8

0.72

B

0.77

0.7

0.63

C

0.6

0.55

0.5

TBT

A

0.77

0.7

0.63

TFT

B

0.6

0.55

0.5

TT

C

0.38

0.35

0.31

QBTQBC

A

0.71

0.65

0.58

QFCQFT

B

0.5

0.45

0.4

QT

C

0.27

0.25

0.22

 

5.Preload and rigidity

High-speed spindle bearing and ball screw support bearings , in normal working condition, should be preloaded with axial load, aiming at improving bearing running accuracy, reducing rolling elements' sliding in high speed, increasing bearing rigidity, decreasing the axial and radial movement of support, increasing bearing damping, reducing noise, increasing bearing service life, etc.

1)The preload and stiffness of angular contact ball bearing

The usual offered preloads of angular contact ball bearing are Light (A), Medium (B) and High (C). Moreover, we can preload bearings with special value on customers' request.

2)Bearing preloads with position preload and constant pressure preload, shown in the Fig. 9 and Fig.10.  

 

1574738432103934.png

                        Fig. 9 Position preloaded

1574738439138218.png

Fig. 10 Constant pressure preloaded

 

As the position preloaded bearing running, the relative position of parts in supporting is fixed. While the angular contact ball bearing running in high speed, the balls tend to be throwed out due to the centrifugal force, which makes the inner ring and outer ring tend to move relatively in axial direction. However, since the position has been relatively constant, the bearing preload will be enlarged and the friction heat willt be intensified. Moreover, with the change of working temperature, the housing dimension and the positioning components dimension will also change, and then bearing preload will be affected. Therefore, pay attention to the effect that the change of preload plays on bearing working performance, while adopting the position preload.

 

The constant pressure preload is to make use of coil spring, belleville spring and other elastic components to make the bearing preloaded properly in the supporting position. Since the rigidity of spring preload is usually much smaller than that of bearing, the constant pressure preload is decided by the preload devices with the constant value. Moreover, the preload level of bearing supporting will not affected by the working temperature.   

 

Summary:The fixed position preload is good for improving bearing rigidity, while the fixed pressure preload is used to high-speed running occasions.

 

Table. 48 The Axial Rigidity Ra of B70 C/HQ1Series Bearings Matched in DB or DF N/μm

 

d

mm

B70 C

B70 C/HQ1

Preload level

A

B

C

A

B

C

10

12

15

17

20

25

30

35

40

45

50

55

60

14

15

17

18

23

29

33

37

41

45

48

55

57

20

22

25

26

33

41

47

53

60

65

69

79

82

25

28

31

33

42

53

59

66

76

81

87

100

103

16

17

19

20

26

32

37

41

46

50

54

62

64

22

25

28

29

37

46

53

59

67

73

77

88

92

28

31

35

37

47

59

66

74

85

91

97

112

115


Why choose the high precision angular contact ball bearings?

REASONS

BENEFIT

REDUCED RUN OUT (P4,P2)

HIGH WORKPIECE ACCURACY

 

HIGH SPEED

SHORTER WORKING TIME

BETTER SURFACE FINISHING

LOW FRICTION

LOW WORKING TEMPERATURE

PRELOAD

HIGH STIFFNESS

 

How to choose the bearings series during the real application?

 

MACHINE

BEARING TYPE

BEARING SERIES

TURNING

HIGH LOAD

70/719/72

MILLING

HIGH LOAD

70/719/72

MACHINING CENTER

HIGH SPEED

H70/H719

HIGH SPEED MILLING

HIGH SPEED +CERAMIC BALL

H70+CERAMIC BALL

GRINDING

HIGH SPEED +CERAMIC BALL

H719+CERAMIC BALL



H718+CERAMIC BALL

 

How to choose the lubrication ways?

 

BEARING TYPE

SPEED FACTOR

LUBRICATION


HIGH LOAD


<1.0 Mndm

Grease


>1.0 Mndm

Oil Bath or circulation


HIGH SPEED

<1.5 Mndm

Grease



>1.5 Mndm

Oil injection or mist or air-oil


HIGH SPEED+CERAMIC BALL

<1.8 Mndm

Grease



>1.8 Mndm

Air-oil or minimal oil lubrication


 

 

How to calculate the speed factor

Speed factor ndm is calculated to compare working conditions of different bearings, regardless their dimensions.

D  = outer diameter (mm) 

d  = bore diameter (mm) 

n  = shaft speed (rpm) 

dm = pitch diameter (mm) 

 

dm = 0.5x(D+d)

ndm = dm x n

 

How to calculate the grease qty?

 

Q0 = 33% free space 

Q = Q0 x K   [cm3]

131313.png 

If you want to learn more information?

Please don't hesitate to contact with us.

 

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