Analysis And Optimization Of Dynamic Seal Performance Of Nitrogen Spring

Nitrogen spring is a kind of elastic element with high pressure nitrogen as working medium.It is widely used in the cold stamping process in the field of automobile mould industry.Compared with the conventional elastic elements,nitrogen springs have many advantages,such as simplifying the design and manufacture of the mould and easy to adjust the mould.Therefore,the application of nitrogen spring improves the level of cold stamping process and caters to the needs of industrial development.At present,there is a problem that the reliability of dynamic seal of the domestic nitrogen spring is poor,which seriously affects the working performance and service life of the nitrogen spring,and restricts the development and upgrading of the domestic nitrogen spring industry.This paper does the following research on the dynamic sealing problem of the nitrogen spring.First of all,the background and significance of studying the dynamic seal performance of nitrogen spring are expounded.By introducing the structure of the nitrogen spring,it is pointed out that the key to ensure the quality of the nitrogen spring is to ensure the reliability of the dynamic seal of the nitrogen spring.The development and application status of nitrogen spring at home and abroad as well as the research progress of related sealing technology are summarized.Then,based on super elasticity theory and Mooney-Rivlin constitutive model,the finite element model of dynamic seal structure of nitrogen spring is established in ABAQUS environment.The influence of the rubber hardness of Y sealing ring,medium pressure and the fit clearance between plunger rod and cylinder sleeve on the performance of nitrogen spring sealing structure under static sealing condition is analyzed.Summarize the reason why the seal performance under static sealing condition is not easy to fail.Next,the stress changes of the Y sealing ring in the reciprocating motion of plunger rod is analyzed.It is revealed that the influence of the rubber hardness of Y sealing ring,medium pressure,friction coefficient and reciprocating velocity on stress,stain and contact pressure of sealing ring.And analyze the reasonable selection range of rubber hardness and fit clearance of different types of nitrogen spring to provide the basis and method for determining the parameters of the dynamic seal structure of the nitrogen spring.Finally,orthogonal test is applied to analyze the significant degree of different factors on the dynamic seal performance of nitrogen spring,and put forward the optimization scheme of the dynamic sealing performance of nitrogen spring.