Analysis Of Residual Stress And Fatigue Life Of Round Pipe Butt Welding

As an indispensable connection method in production and life,welding plays an important role in most of industrial fields.The quality of welding directly affects the safety performance of the weldment during service.Through finite element method for simulation and fatigue analysis of the welding process,not only can shorten the research cycle,but also reduces the cost and manpower of the study.The temperature and pressure of the super-heater tube will change periodically during the work after welding.What's more,fatigue fracture is more likely to occur at welded joints under the cyclic loading.Therefore,it is important to analyze the welding residual force of the super-heater tube and the prediction of the fatigue life.In this paper,ANSYS is used to simulate the welding process of super-heater tubes.The welding temperature field and stress felid change process are obtained by programming to achieve the welding heat loading and moving.After the welding process of the super-heater tube,the welding residual stress of the super-heater tube is reduced to a low level through relevant stress relief work on the weldment.In this paper,the FE-SAFE fatigue analysis software is used to calculate the fatigue life and safety factor of the welded super-heater tube under different conditions.In addition,The effects on the fatigue life and safety factor of the super-heater tubes is obtained,by compared with different loads and whether there is residual residual stresses.At the end of the paper,the shape and size of the super-heater tube are optimized to obtain the optimized fatigue life and safety factor.And the fatigue performance of the super-heater tube is further studied.