The Optimize Design Study On Efficiency Parameters For Coaxial Sealing Based On Response Surface Methodology

The coaxial seal was widely used in hydraulic reciprocating seal system,because of its good sealing performance and self-lubricating properties.The sealing performance of the coaxial seal mainly depended on the material characteristics,cross section shape of the sealing parts,and the operation parameters.The design of the section shape of the seal was largely dependent on the experience and skill of the designer,and the repeated experiments had also increased the cost of design.In recent years,the large finite element analysis software,such as ANSYS,was widely used in the analysis of seal parts to present the pressure and stress distribution.It provided convenient and intuitive methods for the sealing optimization,and greatly improved the accuracy and timeliness of sealing optimize design.First,the optimize design framework on efficiency parameters for coaxial sealing based on response surface method was presented.The static and dynamic(piston rod inside,outside)sealing performance of the coaxial combined seal was compare with the separated rubber o-ring in the same size and work operation by using ANSYS.The analyzed results shown that,the sealing performance of rubber o-ring was better than coaxial combined seal when the seal worked at a relatively lower oil pressure,but with the pressure increasing,the sealing capability of the coaxial combined seal was clearly superior to single o-ring.Than the change laws between sealing performances and static parameters such as structure,material,O-ring compression rate were analyzed,and their best range of values were gotten.The change laws between sealing performances and dynamic operation parameters of coaxial combined seal were also analyzed.The analyzed results shown that,the maximum static contact pressure of the primary sealing surface reduced significantly with the increasing of the sliding ring's thickness,but it increased with the rising of both sides of the sliding ring's chamfering and O-ring compression rate.It was not obvious that the influence of reciprocating motion speed of the piston rod and friction coefficient of sliding ring on the primary sealing surface maximum dynamic contact pressure and the friction between the sealing surfaces.Last,the response surface method was used to optimize the parameters combination of coaxial combined seal,in which the sealing surface maximum contact pressure and minimum friction had been as the optimization targets,and the final program of best structural parameters combination were obtained.The mathematical fitting model that expressed the relations between sealing capability of coaxial combined seal with key efficiency parameters were built,and the validity of the models were tested and verified.