The Finite Element Analysis Of Large Diameter Directly Buried Heating Pipe Welding Tee Strengthened

As district heating to improve energy efficiency and reduce pollution from fuel combustion heating method,in recent years it has made tremendous development.Buried because of its small heat loss,long life and low cost advantages of a central heating main laying.Expanding the size of the heating pipe network to promote heating channel diameter increases,the safe operation of the pipeline are increasingly high requirements.In the heating pipe network welded tee is an important component,but also the safe operation of the important weak points,discrete geometry and complex loads make welded tee intersection there is a great concentration of stress,the strength of welded tee safe operation of the entire heating network is essential.To improve the strength of welded tee,welded tee is necessary to reinforce.However,the current domestic and international research on the buried heating pipe welding tee Strengthened less,the lack of welding engineering practice tee Strengthened theory.Therefore,we use finite element software for Strengthened burried heating pipeline welded tee simulation analysis,the main work is as follows:(1)This paper introduces the importance of the safe operation of the heating pipe network and the important significance of the welded tee to the safe operation of the heating pipe network.This paper describes the current domestic and foreign scholars on the welding tee system and welding system for the welding tee to strengthen the research results.This article provides a brief description for welded tee strengthen research methods and content.(2)Introduction of directly buried heating pipe welded tee by load and studies the theoretical basis of stress classification and the strength theory(3)This paper describes the theory of strengthening welded tee and by comparing the finite element method as selecting research methods,introduces some common ways to strengthen buried welded tee,welded tee buried proposed ways to strengthen the saddle of this study strengthen and comprehensive strengthening.(4)This paper describes the finite element method and analysis software ANSYS,describes in detail the establishment of heating buried welded tee strengthen finite element models,including material properties model definition unit type specification model mesh,mesh independence and applying a test load.(5)Finite Element Analysis of the saddle and strengthen the comprehensive strengthening.Saddle strengthen and comprehensive strengthen all can effectively reduce the directly buried stress level,the welded tee saddle strengthen can make the stress value is reduced up to 26.4%,the comprehensive strengthen can make the stress value is reduced up to 37.7%.Saddle strengthen for small opening rate directly buried welded tee strengthening effect is better,increasing the thickness of the saddle strengthening can improve the strengthening effect;Comprehensive strengthening effect is superior to the saddle.(6)For competent buried in the transition section welded tee,tee stress were analyzed distribution of the strengthened buried welded varies with the amount of displacement of directors found that the stress welded tee maximum points with the amount of displacement of the competent increase transfer from the tee to the inner wall of the outer wall of the abdomen tee abdomen between the shoulders.For executives in buried welded tee transition period,better than the comprehensive strengthening of the saddle strengthened..Compare strengthen both ways,the same amount of displacement in charge of the case,to strengthen the comprehensive strengthening of better than saddle.(7)It summarizes the main conclusions of this paper,and suggestions for future research in this subject.