Oil Condition Monitoring of Spur Gears

Abstract

A protective layer is formed on the gear mating surfaces due to chemical action or physical action of lubricant additives. The gears work under mixed and mixed-elastohydrodynamic lubrication regime. The additives get depleted and degraded over the time due to oxidation, thermal stresses, and hydrolysis. In present work, online monitoring of the gears using oil analysis has been presented and results are confirmed with the offline analysis. The studies are conducted for the three different cases. First to see the effect of load and speed variation; second to see the effect of oil degradation, and third to see the effect of hardness on natural progression of the wear. It is found that the wear of the gear flank is the function of the load, speed, oil degradation and material hardness. The wear rate increased with increased load, speed and oil degradation and hardness plays an important role on gear flank wear.