The basic static load rating (C0r/C0a) is a static load of a defined direction and size where the calculated contact stress of the roller and the raceway at the contact area under maximum stress is 4,000 (MPa). (Contact stress exceeding this value may impede rotation.) This value is indicated as “C0r” or “C0a” in the dimensional table. When a load is statically or dynamically applied, it is necessary to consider the static safety factor as shown below.
| fsr |
Static safety factor for C0r |
| C0r |
Basic static load rating (radial) (N) |
| P0r |
Static equivalent radial load (N) |
| fsa |
Static safety factor for C0a |
| C0a |
Basic static load rating (axial) (N) |
| P0a |
Static equivalent axial load (N) |
Static Equivalent Radial Load P0r
| P0r |
Static equivalent radial load (N) |
| Fr |
Radial load (N) |
Static Equivalent Axial Load P0a
| P0a |
Static equivalent axial load (N) |
| Fa |
Axial load (N) |
| M |
Moment (N·mm) |
| X0 |
Static moment factor(X0=4.6) |
| Y0 |
Static axial factor (Y0=1) |
| Dpw |
Roller pitch circle diameter (mm) |
Static SafetyFactor (fsr, fsa) (Guideline)
| Load conditions1 |
Lower limit of fsr, fsa 2 |
| Without vibrations or impacts |
2 or greater |
| With vibrations or impacts |
5 or greater |
- 1
In general, factors that cause vibration and impacts include acceleration and deceleration, sudden starts and stops, transmission of vibration and impacts from external devices and machines, and changes in processing force over time.
- 2
The values in the table above are guidelines for minimum static safety factors. However, considering dynamic performance such as service life, we recommend a value of 7 or above.
