Transient elastohydrodynamic lubrication of rectangular elastomeric seals for linear hydraulic actuators

Abstract

A numerical model developed previously by the author to study rectangular rubber seals for reciprocating piston rods in hydraulic actuators is extended to include transient effects, considering the sealed pressure and the stroking velocity of the piston rod as time variables. The model incorporates various improvements regarding the treatment of seal extrusion, non-linear seal elasticity effects, as well as the modelling of back-up rings at the air side of the actuator, all of which have been dealt with individually in previous studies by the author. These new features are combined in the present model for a complete analysis of the leakage and friction performance of the seal-ring system under real transient operating conditions of industrial and aircraft actuators, including thermal effects and rough-contact analysis, and covering the widest applicable range of sealed pressures (over 0.1 MPa) and operating temperatures (− 60 to + 140°C).