Engineering & Sizing

L10 Expected Life Calculation

The L10 life represents the theoretical distance the actuator can travel before 10% of a given population shows signs of metal fatigue. It is heavily dependent on the Dynamic Load Rating (C) and the applied Equivalent Load (Fm).

* Roller screws often exhibit an exponent of 10/3 instead of 3 (standard for ball screws), which is why their theoretical life is dramatically higher under identical loads.

Duty Cycle Considerations

Heat dissipation is the primary limiting factor in high duty cycle applications like servo presses. Planetary roller screws can support demanding duty profiles, but ambient temperature, lubrication, heat rejection, and servo motor holding current must be accounted for. We recommend providing a complete motion profile (Force vs. Time and Velocity vs. Time) for a rigorous thermal analysis.

Architecture Selection Rules

The fastest sizing review starts with the failure mode of the current axis: low life, low stiffness, hydraulic maintenance, tight envelope, or missing process data. The actuator architecture should follow that constraint rather than a catalog part number.

Recommended Next Step

If your team already has a duty cycle, drawing, or reference actuator, send it through the contact / RFQ page. If the architecture is still open, compare the product families first. When domestic origin, export-control handling, or supplier geography may affect the RFQ, use the American roller screw sourcing guide to separate compliance evidence from sizing assumptions.

If you are evaluating cost and load trade-offs, refer to the Ball Screw vs Roller Screw Selection Guide to ensure you specify the correct architecture. For an interactive sizing and cost estimation, you can also use our Actuator Procurement Estimator.