Contact Models and Reduction of Instabilities in Sealing Rings for Sustainability Purposes

Instability phenomena in mechanical seals are responsible of malfunction, fluid leakage and noise generation, which in turn lead to disadvantages in terms of Sustainable Development Goals (SDG). Mechanical face seals are mainly employed in pumps used in the automotive and appliance industries. The aim of these seals is to separate two chambers containing fluids, assuring the containment, during the rotation of a shaft. Tribological instabilities can cause a stick-slip behavior, which leads to failures, wear, and fluid leakage with consequent waste of material, increase of costs and pollution, release of fluids potentially dangerous for human health. Thus, reduction of these phenomena will help to achieve SDG12 - Responsible Consumption and Production, SDG9 - Industry, Innovation and Infrastructure, and SDG3 - Good Health and Wellbeing. Proper mathematical models are very useful to predict instabilities and optimize the service conditions. In this paper, tribological models based on different contact theories are compared in terms of stick-slip predictivity, with respect to experimental data gathered with a dedicated tribometer. Results allow to discuss the accuracy of different theories in predicting the critical speed of the seals corresponding to the manifestation of instabilities and leakages.