Design Research And Test Of Special Flange Connection Sealing Structure For Large Carrier Rocket

There are all kinds of equipments and connecting pipes in large carrier rocket,the safety and reliability of flange connection sealing structure are directly related to the success or failure of launch mission.This paper in view of a large diameter flange connecting sealing structure in large carrier rocket for the design and analysis,which adopts traditional flange design rules and EU alternative flange design rules for this type of flange connecting sealing structure.Based on the flange which designed by EU alternative flange design rules,the finite element analysis and structure optimization were carried out.Designed and established test apparatus for the flange connection sealing structure,the finite element analysis and calculation of test apparatus were carried out,completed the helium test and hydrostatic test of the test apparatus.Firstly,the development status and existing problems of special flange connection sealing structure for large carrier rocket were summarized,and the development history and characteristics of traditional flange design rules and EU alternative flange design rules were analyzed,providing design ideas and rules for the design of special flange connection sealing structure of large carrier rocket.Secondly,according to design conditions and parameters,theoretical calculation and structural design of special flange connection sealing structure for large carrier rocket based on traditional flange design rules and EU alternative flange design rules were completed.The characteristics and results of traditional flange design rules and EU alternative flange design rules were compared and analyzed,the application of the two rules is suggested.At the same time,finite element analysis was carried out on the special flange connection sealing structure for large carrier rocket based on EU alternative flange design rules by using ABAQUS software.The analysis results showed that the design result can achieve effective sealing under both installation and subsequent working conditions.The sealing structure was optimized by finite element simulation analysis to improve the sealing reliability.In addition,used ABAQUS software to establish the finite element model of metal O-ring seal,O-ring seal under the different conditions of sealing performance and the compression resilience to the elastic-plastic analysis,obtained the good elastic-plastic finite element analysis results,the results showed that metal O-ring seal has good capability of springback and the tight sealing function,meet the design needs.Finally,designed the test apparatus of sealing structure,finite element analysis for the test apparatus was calculated and the structure intensity evaluation intensity was accomplished.Completed sealing structure test apparatus helium test and hydrostatic test,helium test and hydrostatic test were qualified,the leakage rate meets the design requirements,the sealing effect is good.