Dynamic Modeling of Gear Tooth Pitting Propagation to Neighbouring and Mating Teeth

Tooth pitting is a common failure mode of a gearbox. Many researchers investigated dynamic properties of a gearbox with localized pitting fault on a single gear tooth or pitting propagation to neighboring teeth. The dynamic properties of a gearbox with pitting propagation to both the neighboring teeth and mating teeth have rarely been investigated. In this paper, circular pits are used to model gear tooth pitting propagation to neighboring and mating teeth. Three pitting damage levels are considered: slight pitting, moderate pitting and severe pitting. Pitting growth is reflected by mesh stiffness reduction of gear pairs. A lumped parameter model is applied to simulate vibration responses of a fixed-axis gearbox with spur gears. Pitting effects on gearbox vibration properties are studied.