Theoretical concept for in-situ condition monitoring of rotary shaft seals using surface strain-based analysis of the deformation state

In situ condition monitoring of rotary shaft seals could significantly improve the reliability of future seals in numerous applications. A superficial application of strain gauges capturing the state of deformation could offer a cost-effective retrofit solution for indirect measurements of central operational parameters. This simulative study therefore serves to identify possible sensor positions enabling a surface strain-based determination of the elastomer preload as well as the friction torque prevailing in the sealing contact. Both parameters are directly related to the operational conditions of the seal system. Further investigations of the potential sensor signal with focus on its time-dependent behavior prove the theoretical feasibility of the measurement concepts developed and provide promising prospects for an initial technical implementation.