The Theoretical Analysis And Experimental Research Of Friction Characteristic Of Hydraulic Reciprocating Seal

Hydraulic reciprocating seal is the most widely used seal in dynamic seal,the sealing performance of which isrelated withlubrication,friction,wearin sealing interface sealing structure,seal material and other factors.Among them,the frictioncausedby reciprocating motion of the moving parts affects the deformation of seal,whichwill change the pressure distribution in sealing contact area.It will alsoaffectthe formation of liquid film,eventually causethe change of oil film thickness and friction force in the sealing contact area.And hydraulic reciprocating seal friction is closely related to wear,lubrication in seal surfaceand fatigue of sealcaused by alternating load,and these factors have mutual coupling effect,so it is a complex phenomenon.Because the friction has an important influence on the normal function and efficiency of the equipment,and high friction may cause the overheating and excessive wear of seal.Therefore,the study forthe frictioncharacteristicof hydraulic reciprocating seal is very important.Aiming at these problems,the paper is based on theoretical research for the friction characteristic of hydraulic reciprocating seal hydraulic,cylinder piston seal,and takes typical hydraulic reciprocating seal--cylinder piston sealan example,to explorethe testing method based on the fiber Bragg grating sensor for the frictioncharacteristicof hydraulic reciprocating seal,and the friction and wear testing for the seal material are made on friction and wear test machine to compare and verify.The following aspects are mainly studied:(1)The related theory of the frictioncharacteristicof hydraulic reciprocating sealis analyzed,and on the basis of the Reynolds equation,the calculation model of friction force of the hydraulic reciprocatingseal is given,which provides a theoretical foundation forthe calculationof friction characteristic value in in the subsequentpaper.(2)The hydrauliccylinder piston seal is taken as an example,by studying the experiment system to test friction characteristic ofhydraulic reciprocating seal is established,and the optical fiber grating sensors are designed to test the sealing contact pressure,then the friction characteristic valueof hydraulic reciprocating sealiscalculated.And the influence of the medium pressure,the wear and teardegree of sealing ring and sealing ring material on friction characteristic of hydraulic reciprocating seal is analyzed.(3)The friction and wear test of nitrile butadiene rubber and polyurethane are made on friction and wear test machine,and the average friction coefficient of both friction pair of nitrile butadiene rubber-45 steel and polyurethane-45 steel are testedand the contrast analysis is made,in order to verify the feasibilityof the testing method based on the fiber Bragg grating sensor for the frictioncharacteristicof hydraulic reciprocating sealand the effectiveness of the friction characteristic value that this paper puts forward.