Abrasive Wear Failure Behaviors Of Rubber Seal In Particle-contained Aqueous Medium

Rubber seals are widely used in the fluid seals in industry,aerospace,national defense and other fields because of their good sealing performance and machinability.Rubber seals are important seals to ensure the normal operation of the fluid machinery.When the pollutants such as hard particles invade the interface of rubber sealing rings,the lubrication film between the friction pairs will be destroyed and the abrasive wear of the friction pairs will be aggravated,thus greatly reducing the reliability and service life of the fluid machinery.Therefore,it is important to explore the tribological behavior of rubber seals in the environment containing the hard particles and to reveal the mechanism of particle-induced rubber wear failure.In view of this,in this dissertation,based on the tribological principle,the research of the failure mechanism of abrasive wear of rubber seal in aqueous environments containing particles.Firstly,an environmental simulation device with granular medium is built.The device can create an external particle environment with different particle sizes and particle concentrations.In this dissertation,seven particle sizes and five particle concentration test environments are provided.The abrasive wear of NBR and 316L stainless steel pairs in the water medium containing Al₂O₃ hard particles is studied.Secondly,the effects of particle size and concentration on wear failure of NBR were investigated through a large number of experiments.Based on tribology principle,the time-varying curves of wear morphology,wear amount and friction coefficient of friction pairs under the different particle environments were compared and analyzed.The results show that the average friction coefficient of NBR is higher than that of NBR in pure water,which is different from the"size effect"in dry condition.When the particle size is larger than 500mesh,the wear form of friction pair is mainly the micro-cutting;when the particle size is less than 5000 mesh,the wear form of friction pair is mainly the rolling wear,when the particle size is between the two,the wear form of friction pair includes micro-cutting and rolling wear.The hard particles embedded in the NBR friction surface form a grinding wheel-like phenomenon,and the wear severity increases with the increase of particle size and concentration.Finally,the size of particles and particle concentration factors comprehensive influence of two,based on tribology principle,analysis of nitrile rubber abrasive wear effect in aqueous medium,The results show that particle size plays a dominant role in abrasive wear of NBR at low particle concentration.Particle size determines the form of three-body wear,while particle concentration can only aggravate or slow down the degree of wear.The hard particles can accelerate wear when they enter friction pairs,especially when the size of the intrusive hard particles was larger,the wear of friction pairs is more serious.Through the research of this dissertation,it provides theoretical guidance for the anti-abrasive wear behavior of fluid mechanical seals.At the same time,it is suggested that in engineering application,filter screen,skirt plate and other protective devices should be added to the outer side of the seals to minimize or even avoid the invasion of pollutants,so as to improve the reliability and service life of the whole machine.This dissertation investigates the mechanism of hard particles on the material removal of friction pairs.The effect of particle size and particle concentration on the abrasive wear is clarified.The research results provide theoretical support for improving the reliability and life time of the rubber seals.Based on this study,the next step is to study the wear failure of rubber in oil-containing media and different particle compositions under actual working conditions.