Study On Recessive Defects In Electromagnetic Heating Process Of Induction Welding Steel Pipe

With the continuous expansion of pipe application in various industries,the requirements for manufacturers are also gradually improved.The contradiction between the quality and output of welded steel pipe is gradually prominent,which poses a great challenge to the coordinated development of production quality and output.With the application of electromagnetic metallurgy technology in iron and steel industry,some unique defects have been gradually improved.However,after investigation,the application of this technology still has product defects caused by inherent skin effect and proximity effect,which greatly limits the role of welded pipe in harsh environment.In order to improve this defect,this paper proposes a precision heating technology,that is,the fusion of the welding process and heat treatment process of the steel pipe is simulated and analyzed.It is concluded that the hidden defects in the fusion process of the welded steel pipe are different from the conventional defects,and the hidden defect rate is reduced by optimizing the heat treatment process,so as to improve the service reliability of the welded pipe.In order to further reveal and quantitatively characterize the generation and evolution process of hidden defects in welded steel pipe,the process of induction welding and medium frequency heat treatment of steel pipe is analyzed as a whole,the electromagnetic thermal coupling model is established,the scope,generation process,accurate positioning and quantitative evaluation of hidden defects are clarified,and the influence of coil parameters and heat treatment parameters on hidden defects is revealed.Taking the process of high frequency induction welding and medium frequency heat treatment as the research object,the hidden defects of induction welded steel pipe during electromagnetic heating were studied by combining simulation and experiment:first,The electromagnetic thermal coupling calculation model of high frequency induction welding and medium frequency heat treatment process is established,and the distribution of electromagnetic field and temperature field in weld area is analyzed by adopting three times induction heating under the new induction coil.Secondly,Based on the establishment of multi field coupling prediction model,the influence of coil geometry parameters and heat treatment parameters on the hidden defects of steel pipe was studied by analyzing the process of high frequency induction welding and medium frequency heat treatment under different induction heating times.The last,The temperature measurement experiment of medium frequency induction heating was carried out,At the same time,the mobile induction heating method is used to simulate the process.On the basis of accurate simulation calculation,the experimental data and simulation data are compared to verify the reliability of the simulation method.