Single-row radial ball and roller bearings have a favorable factor of rolling friction and can be used for higher speeds than other bearing types. Limiting speed is also affected by the type of lubricant used and the cage material is also important. Common pressed sheet steel cages are convenient for regular speed and brass or other materials used more for higher speeds. The guiding speed for bearings with ordinary degree of precision are presented in the tables. It is necessary to consider the falling of limiting speed in radial bearings which are constantly loaded with axial force. In this case limiting speed depends on F a /F r ratio. The table presents values of f n factor, by which it is necessary to multiple limiting speed presented in the table.
|
Bearing type |
F a /F r |
|||||||||
|
0.25 |
0.40 |
0.60 |
1.00 |
1.60 |
2.50 |
4.00 |
6.00 |
10.00 |
> 10 |
|
|
Ball single-row |
1.0 |
0.98 |
0.96 |
0.92 |
0.89 |
0.86 |
0.82 |
0.82 |
0.81 |
0.80 |
|
Ball single-row with angular-contact |
1.0 |
1.0 |
1.0 |
1.0 |
0.98 |
0.97 |
0.96 |
0.96 |
0.95 |
0.95 |
|
Ball double-row self-aligning |
0.98 |
0.93 |
0.85 |
0.72 |
0.62 |
0.58 |
0.45 |
0.43 |
0.38 |
0.33 |
|
Spherical-roller double-row |
0.99 |
0.95 |
0.90 |
0.82 |
0.77 |
0.72 |
0.67 |
0.64 |
0.62 |
0.60 |
|
Tapered roller single-row |
0.98 |
0.93 |
0.88 |
0.78 |
0.69 |
0.61 |
0.55 |
0.51 |
0.48 |
0.45 |