Based On The ANSYS Of X60 Steel Pipe Welding Temperature Field And Stress Field Numerical Simulation

Pipelines are mainly used in modern industry to transport oil,natural gas,high te mperature and high pressure steam,etc.In recent years,due to many advantages such as large transportation volume,good economy and high safety of pipeline structure,it has been widely used in chemical industry,petroleum and natural gas and other impo rtant sectors of national economy,which has attracted the attention of experts and sch olars at home and abroad.Pipe welding process,the welding heat source under the acti on of joint imbalance of thermal process,after welding,welding residual stress and de formation of welding residual stress and deformation of the bearing capacity of pipe welding joint or structure,service life will bring unfavorable influence,severe cases ca n cause cracking medium leakage accident causing the pipe structure.The residual stres s and deformation of pipeline welded structure are controlled and reduced by different technological schemes,which has become an important subject of domestic and forei gn experts and scholars.With the improvement of the theory of computational welding mechanics and the rapid development of computer technology,numerical simulation tec hnology has been widely used to predict the residual stress and deformation of weldin g structures.In this paper,the residual stress of v-groove butt joint of 10mm wall thickness X 60 steel pipe channel is simulated by ANSYS.The temperature field,strain field and d eformation of welded pipe joints are simulated by indirect coupling method.According to the simulation results,the process optimization scheme is proposed,and then the o ptimization scheme is numerically simulated,and the calculated results are compared with those before optimization.Optimized process parameters were used to weld the X60 pipeline.After the completion of the welding,the residual stress of the welding was measured by blind hole method and the deformation of the pipeline welding was me asured by coordinate measuring instrument.The experimental results are compared and verified with those obtained by finite element simulation.This proves that the finite ele ment method can effectively predict the residual stress and deformation of pipe weldin g,which can provide a theoretical basis for the control and reduction of the residual stress and deformation of X60 steel pipe channel.The research results show that:(1)In the multi-pass welding process of pipeline,the temperature field is distribut ed in quasi-steady state and changes dynamically with the movement of heat source.(2)The higher the temperature is near the heat source,the higher the rate of hea ting and cooling.(3)The maximum residual stress is generated on the first welding seam,resulting in obvious plastic deformation.This is due to the v-groove caused by the weakest ar ea at the first weld,inevitably produce a large plastic deformation and residual stress.In the actual welding process,the heat input can be reduced appropriately or other te chnological means such as sectional welding can be adopted to avoid this situation.(4)the deformation of the whole model is mainly generated in the axial direction rather than the radial direction.Therefore,if pipe welding wants to further reduce th e overall deformation,it can mainly choose to apply fixed constraints in the axial dire ction.