Consideration of the influences of the driving direction within the calculation of the pitting load-carrying capacity of bevel and hypoid gears

Abstract Pitting is, besides scuffing, tooth flank fracture and the phenomenon micropitting, one of the primary failure modes of the flank load-carrying capacity of bevel and hypoid gears. The international standard ISO 10300-2:2014 is widely used for the estimation of the flank load-carrying capacity of bevel and hypoid gears based on operational data and the macrogeometry of the gear set. The calculated safety factors against pitting often show similar values for pinion and wheel. Due to similar safety factors against pitting, the gear is expected to fail as often as the pinion. However, investigations in the field do not confirm this. Initial experimental investigations show an influence of the driven and driving part of the gear set. Within this paper, the phenomenon regarding the driven and driving part of the gear set will be discussed for the first time and the influence parameter will be clarified. Because of the potential for recuperation in electrified agricultural tractors, railroad trains, hybrid and electrical vehicles, this topic is of great importance. In this context an actual calculation approach based on the standard calculation method of the ISO 10300-2:2014 will be presented and verified with test results.