Research On Sealing Performance Of Flared Pipe Joint

As one of the important connection structures widely used in aerospace,machinery manufacturing and energy industries,the pipe joint has the main function of enabling the components in the equipment to work together reliably.Among them,the flared pipe joint is compact and easy to load and unload.Convenience and other advantages are widely used in engineering.Flared pipe joints usually work in complex environments such as high temperature,high pressure and vibration.The sealing performance will slowly decline,that is,the seal declines,and it is prone to media leakage during long service in extreme environments.Pipe joints Once a seal failure occurs,it wastes resources and pollutes the environment,and even lowers the work efficiency of the equipment or even causes a fatal disaster.Therefore,the research on the sealing performance of flared pipe joints has important engineering application value.This article systematically studies the influence of the structural parameters and environmental load of the flared pipe joint on its sealing performance from the perspective of theoretical analysis and numerical simulation.Finally,it attempts to explore a new type of sealing structure in terms of structural form and combines multiple sealing performance evaluations.Indicators to verify the effectiveness of its improved methods.The work carried out in this article mainly includes the following aspects:1)The relevant theories and research status of the sealing performance of flared pipe joints are systematically sorted out,and the problems to be solved are pointed out.Based on the model specification of flared pipe joints,the geometrical characteristics are analyzed,and the formation process of the initial seal of the pipe joints is simulated.The above work provides preliminary knowledge and theoretical basis for subsequent research.2)The influence of flared pipe joint structural parameters on its sealing performance is studied.First,parametric modeling of flared pipe joints was carried out to determine the reasonable value range of initial preload,and an automatic analysis method was used to explore the influence of some structural parameters on their sealing performance;then based on the Isight optimization platform The experimental design and deterministic optimization of the structural parameters of the flared pipe joint;finally,considering the influence of the modeling uncertainty of the pipe joint,a reliability optimization design framework based on the Kriging agent model is constructed and verified by the Monta Carlo method Reliability optimization results are correct.This research method provides a reference for the optimal design of pipe joints.3)The effect of environmental load on the sealing performance of flared pipe joints is studied.Firstly,the thermophysical properties of the material of the flared pipe joint model are considered,and the influence law of ambient temperature and medium pressure on its sealing performance is obtained;then on this basis,the amplitude and frequency of fluid pulsating pressure are carried out on its sealing performance The impact of the work;finally,for the connection loosening of the flared pipe joint during service,the creep characteristics of the model material were considered,and the sealing performance degradation law under cyclic temperature load was obtained,and the flared pipe was established.The refined finite element model of the joint has obtained its sealing performance degradation law under vibration environment.This research method provides a reference for the research on the sealing performance degradation law of pipe joint under complex environmental load.4)Explored a new type of sealing for pipe joints.Aiming at the improvement points of the initial sealing performance,structural compensation performance,fatigue resistance and anti-loose ability of pipeline joints,attempts were made to improve the flared pipe joints from the structural form,and the effectiveness of the improved method was verified.