Assessment of Residual Useful Life of Sun Gear in a Planetary Gearbox Based on Dynamic Wear Behaviors Analyses

Abstract

For proactively arranged downtime and maintenance of the gearbox, the accurate assessment of residual useful life (RUL) for worn-surface gear is a critical problem that needs to be solved. In light of this, a novel dynamic assessment methodology for RUL of sun gear was proposed by coupling Archard’s wear model and a nonlinear dynamics model. By modifying the internal excitation model, the effect of tooth surface wear is included in the dynamics model. Then, the effect of dynamic behavior on the wear process of the tooth surface is further fed back by the dynamic meshing force. On this basis, the influence of input speed, torque load and initial wear depth on the RUL was analyzed using a planetary gear NGW11-6 as an example. The results indicate that the torque load has the greatest influence on the RUL, followed by the initial wear depth, and that the input speed has the least influence. The established methodology will provide a theoretical basis for the RUL assessment and scheduled maintenance of transmission systems with worn-surface gears.