The service life in revolutions refers to the total number of revolutions that a shaft, spindle, ball screw, or bearing can perform under specific load and operating conditions before functional wear or failure occurs. It is a key parameter in mechanical and drive engineering, as many components are subjected to cyclic loading.
The service life in revolutions is particularly meaningful for:
- rotating components such as spindles or shafts
- Screw drives in which the rotation is directly linked to the linear motion of the nut
- Calculation of dynamic stress and wear rate
It serves as the basis for converting to operating hours and for service life planning.
Factors
- Axial and radial loads: Higher forces reduce service life
- RPM: At high RPMs, friction and heat generation increase
- Lubrication and Sealing System: Proper lubrication reduces wear
- Material and hardness: harder materials can withstand greater loads
- Preload of the nut: affects the load distribution across the balls
- Environmental conditions: temperature, dust, humidity, etc.
The service life in revolutions is relevant for:
- Sizing of spindles, bearings, and nuts
- Maintenance and Replacement Planning
- Comparison of Design Variants
- Ensuring reliability