How the service factor affects gearbox selection

Catalog ratings are published under a reference duty. The service factor adjusts those ratings to the actual application.

Load classes are normally grouped by uniformity: uniform load, moderate shock and heavy shock. Daily operating hours further raise the required factor.

A mixer with high start-up torque, a conveyor under impact load and a pump in continuous service each need a different factor for the same gearbox family.

Selecting with too low a factor risks tooth fatigue and premature failure; an unnecessarily high factor forces a larger frame and higher cost.

Provide the load class, operating hours per day and start frequency so the selection team can confirm the factor and the frame size.