Angular contact ball bearing

Basic types of angular contact ball bearings

The single-row angular contact ball bearing can bear the radial and axial loads. Although this kind of bearings can bear the one-way axial load only, but it can work together with another bearing which bears the opposite load. The angular contact ball bearing is non-detachable. The angular contact ball bearing is applicable to high rotation speed, and its self-aligning ability is very limited.

Tolerance

The contact angle of 72B and 73B type EBC single-row angular contact ball bearing is 40°, therefore it can bear a bigger axial load.

72B and 73B type angular contact ball bearings are manufactured with common tolerance (tolerance grade PN, without suffix).

Permissible rotation speed

In proper working conditions, the bearing rotation speed may exceed the reference rotation speed, but may not exceed the value of limit rotation speed. The thermal allowable rotation speed shall fully consider the influence of special working environment.

If the reference rotation speed in the table is higher than the relevant limit rotation speed, you may not choose the higher values. If the angular contact ball bearings are directly mounted side by side, the special measures should be taken to reach the high rotation speed of individual bearing.

Single-row angular contact ball bearing will have axial component force when bearing radial load. For this reason, two bearings should be used back to back or face to face.

A contact angle exists between rings and balls. The standard contact angles are 15° , 25° and 40° . The more the contact angle is, the higher the capability to bear axial load will be. The less the contact angle is, the more advantageous to rotation it will be.

Single-row bearing can bear axial load and unidirectional axial load.

Double-row angular contact ball bearing has such two types of structure as one outer ring and two inner rings and one outer ring and one inner ring.

DB combination. DF combination and double-row bearing can bear radial load and bi-directional axial load. DT combination is applicable to occasions where unidirectional axial load is high and the rated load of a single bearing is not sufficient. Two single-row angular contact bearings combined back to back in structure have common inner and outer rings, capable of bearing axial load and bi-directional axial load. 

Angular contact bearing is suitable for rotation at a high speed and accuracy.

Such bearing is mainly applied to main spindle machine tool main shaft, high frequency motor, internal combustion turbine, oil pump, air compressor, printing machinery, etc.

Four-point contact ball bearing

Such bearing is mainly applied to airplane jet engine and internal combustion turbine.

It is capable of bearing radial load and bi-directional axial load. A single bearing can replace angular contact ball bearing with back to back or face to face combination.

It is applicable to bearing pure axial load or combined load with a high axial component.

Such bearing will have a contact angle (α) formed when bearing axial load in any direction, therefore, rings and balls always contact with each other at two points on any contact line.

Four-point Contact Ball Bearing Model QJ000 (176000) is the separable bearing, with double half inner rings and the contact angle at 35° . Model QJF000 (116000) is also the separable bearing, with double half outer rings and the contact angle at 35° . The four-point contact ball bearing is mainly used to bear the bi-directional axial load, also available to bear the radial load at the same time.

Angular contact ball bearing installed in pairs

Angular contact ball bearing installed in pairs is divided into three categories by the outer ring end face combination:

1.Back to back configuration (DB)

2.Face to face configuration (DF)

3.Serial configuration (DT)

Such bearing can bear combined load in radial, axial directions with the radial load as the main part. It can also bear pure radial load. Besides serial configuration, other configurations can also bear bi-directional axial load.

Usually the manufacturer determines its combination or provides to users in full set. There will be pre-interference and the rings and steel balls in a state of axial preload after installation. As a result, the load bearing capability and rigidity are improved for a whole combination as a single support

Equivalent dynamic load

For single-row angular contact ball bearing at a contact angle 15°

In case of single bearing or serial configuration

P=Fr　　　　 [N]当Fa/Fr≤e

P=0.44Fr+YFa [N]当Fa/Fr>e

In case of back to back, face to face configuration

P=Fr+Y1Fa    [N]当Fa/Fr≤e

P=0.72Fr+Y2Fa[N]当Fa/Fr>e

Please refer to the following table for values of e, Y,Y1,Y2

Note: Cor is the basic rated static load for single bearing.

For single-row angular contact ball bearing at a contact angle 25°

In case of single bearing or serial configuration

P=Fr            [N]当Fa/Fr≤0.68

P=0.41Fr+0.87Fa [N]当Fa/Fr>0.68

In case of back to back, face to face configuration

P=Fr+0.92Fa     [N]当Fa/Fr≤0.68

P=0.67Fr+1.41Fa [N]当Fa/Fr>0.68

For single-row angular contact ball bearing at a contact angle 40°

In case of single bearing or serial configuration

P=Fr            [N]当Fa/Fr≤1.14

P=0.35Fr+0.57Fa [N]当Fa/Fr>1.14

In case of back to back, face to face configuration

P=Fr+0.55Fa     [N]当Fa/Fr≤1.14

P=0.57Fr+0.93Fa [N]当Fa/Fr>1.14

For four-point contact ball bearing

P=Fr+0.66Fa     [N]当Fa/Fr≤0.95

P=0.6F+1.07Fa   [N]当Fa/Fr>0.95

For double-row angular contact ball bearing

P=Fr+0.78Fa     [N]当Fa/Fr≤0.8

P=0.63Fr+1.24Fa [N]当Fa/Fr>0.8

Equivalent static load

For single-row angular contact ball bearing at a contact angle 15°

In case of single bearing or serial configuration

Po=0.5Fr+0.46Fa [N]

当Po<Fr取Po=Fr

In case of back to back, face to face configuration

Po=Fr+0.92Fa [N]

Equivalent static load

For single-row angular contact ball bearing at a contact angle 25°

In case of single bearing or serial configuration

Po=0.5Fr+0.38Fa [N]

当Po<Fr取Po=Fr

In case of back to back, face to face configuration

Po=Fr+0.76Fa  　[N]

For single-row angular contact ball bearing at a contact angle 40°

In case of single bearing or serial configuration

Po=0.5Fr+0.26Fa [N]

当Po<Fr取Po=Fr

In case of back to back, face to face configuration

Po=Fr+0.52Fa    [N]

For four-point contact ball bearing

Po=Fr+0.58Fa    [N]

For double-row angular contact ball bearing

Po=Fr+0.66Fa    [N]

When two or more sets of single-row angular contact ball bearing are installed together as an integral support, the basic rated dynamic load is i^0.7×Cr, the basic rated static load i×Cor (where i is the number of single bearings in the integral support Cr and Cor are the basic rated load of a single bearing). The rotation speed limit is equivalent to 60%～80% of that of a single bearing.