Calculating the Static Safety Factor
To calculate a load applied to the LM Guide, the average load required for calculating the service life and the maximum load needed for calculating the static safety factor must be obtained first. In a system subject to frequent starts and stops, placed under cutting forces or under a large moment caused by an overhang load, an excessively large load may apply to the LM Guide. When selecting a model number, make sure that the desired model is capable of receiving the required maximum load (whether stationary or in motion). Table9 shows reference values for the static safety factor.
Table9 Reference Values for the Static Safety Factor(fs)
| Machine using the LM Guide | Load conditions | Lower limit of fs |
|---|---|---|
| General industrial machinery | Without vibration or impact | 1.0 to 3.5 |
| With vibration or impact | 2.0 to 5.0 | |
| Machine tool | Without vibration or impact | 1.0 to 4.0 |
| With vibration or impact | 2.5 to 7.0 |
| When the radial load is large |  |
|---|---|
| When the reverse radial load is large |  |
| When the lateral loads are large |  |
| fS | Static safety factor |
|---|---|
| C0 | Basic static load rating (radial direction) (N) |
| C0L | Basic static load rating (reverse-radial direction) (N) |
| C0T | Basic static load rating (lateral direction) (N) |
| PR | Calculated load (radial direction) (N) |
| PL | Calculated load (reverse-radial direction) (N) |
| PT | Calculated load (lateral direction) (N) |
| fH | Hardness factor (see Fig.8 on Calculating the Modified Nominal Life) |
| fT | Temperature factor (see Fig.9 on Calculating the Modified Nominal Life) |
| fC | Contact factor (see Table10 on Calculating the Modified Nominal Life) |
