Method for calculating the application factor KA in gears subjected to variable working conditions

The present paper aims to propose a method, in ISO Standard environment, in order to calculate the KA application factor when the nominal torque is not defined. A procedure is presented, based on the Miner damage rule, in order to process a given load spectrum and to calculate a value of the equivalent tangential force including variable amplitude effects, useful for bending and pitting life calculation. A practical case is presented, based on a recorded vehicle mission, referring to the input gear of a transfer box for industrial truck. A comparison is also given with the ISO Standard results.