Effects of Fluid Properties on Rod Seal Stick‐Slip Mechanical and Sound Vibrations

Abstract

The effect of fluid properties on hydraulic cylinder rod seal stick‐slip friction was studied. Breakaway and stick‐slip forces were measured for three ISO VG 32 fluids with slipper, U‐cup, and Vee‐pack seals. Breakaway forces increased exponentially with dwell time. Stick‐slip friction produced audible low‐frequency noise. Differences in the stick‐slip behavior of the fluids were observed. Fast Fourier transform analysis of sound, force, and mechanical vibrations was conducted. Stick‐slip friction increased the amplitude of low‐frequency vibrations in all three domains. Micro stick‐slip movement was elucidated via motion amplification technology. These findings provide a basis for the development of fluids that improve the control and safety of hydraulic equipment.