Sliding Wear Calculation in Spur Gears

Abstract

In gear applications where precipitous tooth failure mode such as scoring or scuffing has been avoided, “normal” wear becomes a life-determining factor. In this paper, sliding wear in spur gears, including the considerations of gear dynamics and rough-elastohydrodynamic lubrication, is analyzed. Formulas for equivalent wear rate and tooth wear profile along the line of action are derived. Results show that most materials are removed from both the addendum and dedendum tooth surfaces, and that the highest wear occurs at the beginning of an engagement. This high wear region corresponds to the root of the driving (pinion) teeth and the tip of the driven (gear) teeth. These analytical results correlate well with the practical evidences in AGMA documentation.