Physically Based Modeling of Reciprocating Lip Seal Friction

Abstract

Lip seal friction under constant speed sliding is modeled as the sum of three physically based components: (1) viscous shear loss in the lubricant; (2) hysteresis losses due to roughness-imposed deformation of the seal material, and (3) hysteresis losses due to deformation caused by varying intermolecular forces at the sliding interface. Increasingly thick hydrodynamic films progressively reduce contributions of the roughness and intermolecular components. Peaks in friction expected from these two components are smaller, occurring at lower sliding speed, than in “dry” rubber friction. Model simulations capture friction trends with temperature, hydraulic pressure, seal material, lubricant viscosity and shaft roughness.