The fundamental constructive characteristic of double row angular contact ball bearings is that the action line of the charges between the balls and the rolling tracks form a specific angle with the geometric axis of the bearing. For this reason, the bearing tracks of the inside and outside rings are axially displaced between them.
The double row bearings have the same characteristics as would two single row bearings set in an O assembly but not as wide.
The version that FERSA markets has an outside ring and two inside rings that can open and close with sealing washers, depending on the application. They also contain grease, can be disassembled, etc.
One significant point is that these types of ball bearings do not permit any type of alignment defect, since this would mean that the bearing’s ball/track contact would be subject to greater stress than calculated, and therefore unacceptable.
A summary of their Operating Characteristics can be seen in the following outline:
RADIAL
LOADS |
AXIAL
LOADS |
COMBINED
LOADS |
HIGH
SPEED |
| BUENO |
BUENO |
BUENO |
ACEPTABLE |
HIGH
PRECISION |
RIGIDITY |
DISALIGN.
ANGULAR |
SEPARABLE
RINGS |
NOT APPLICABLE
|
NOT APPLICABLE
|
POOR |
NOT APPLICABLE
|
FERSA manufactures these types of bearings in both Metrics and Inches dimensions in these following ranges:
| DIMENSIONES RANGE |
d |
D |
T |
| Min |
mm |
30,000 |
60,030 |
18,000 |
| Max |
50,000 |
139,000 |
64,000 |