Rubber and Plastic seals playing a pivotal role in fluid machinery equipment. However, abrasive wear is the main failure mode of the sealing pairs. This study developed an experiment of the abrasive wear test of the PTFE cylindrical pin and 316L stainless steel under abrasive-contained oil-lubricated conditions. A tribo-tester with mixed abrasives supply was used, the tribological properties of sealing pair under the action of particle size, particle concentration, contact pressure, and oil-viscosity were evaluated. Meanwhile, the lubrication state of tribo-interface, particle running behaviour, and wear mechanism were compared. The results showed that particle size had a significant effect on the wear mechanical and tribological properties of sealing pairs under oil-lubricated conditions. Except for pure oil-lubricated states, the friction coefficient was negatively correlated with the wear level of 316L worn surface and particle size. A particle critical value of approximately 10 μm was obtained, which is related to the time-variable characteristics of the friction coefficient and the failure mode of sealing pairs. Particle running behaviour and damage mechanism before and after the particle critical size are significantly different. Significant variations in the friction coefficient, lubrication state, and particle running behavior of the sealing interface via a change in the contact pressure and oil-viscosity.
 

Rubber and Plastic seals, friction interface, lubrication state, particle size, abrasive wear