Research On Metal Deformation Sufficiency Of Seamless Steel Tube During Continual Mandrel Rolling Process

Seamless steel pipe is widely used in aerospace,petroleum exploration,urban transportation,chemical industry and electronic industry.Since the 13 th five year plan,the steel pipe industry has been improving in terms of product technology and quality level.However,in the development process of China’s steel pipe industry,the cost pressure,capital risk and environmental constraints are increasing,and the deep-seated structural contradictions are becoming increasingly prominent.In order to improve the production efficiency of seamless steel pipe,reduce energy consumption and achieve the goal of carbon neutralization,this paper proposes to study the deformation adequacy of the existing continuous rolling process in order to obtain a more reasonable continuous rolling deformation theory.In this paper,the metal deformation law in the continuous rolling process of seamless steel pipe is studied,the mathematical modeling is carried out respectively,and the simulation model is established by using DEFORM-3D simulation software to obtain the stress,strain and force energy parameters of the pipe in the continuous rolling process,further study the metal deformation behavior of the steel pipe,discuss the adequacy of deformation,and obtain the reasonable rolling passes and process parameters.At the same time,the rationality is verified by experiments,The process theory of high efficiency and low consumption is obtained.The work of this subject is as follows:(1)Study on rolling process of seamless steel pipe hot continuous rollingBased on the continuous rolling process,combined with the deformation performance characteristics of Q235 and the existing pass,a set of basic formulas for the continuous rolling process are formed according to the metal deformation law of the pipe pass.The rolling force,rolling torque and side wall arc ratio in the continuous rolling process of steel pipe under different parameters are analyzed,and the influence of steel pipe process parameters on the metal flow law in the pass is deeply studied;(2)Using DEFORM-3D platform and referring to the experimental data,the continuous rolling of steel pipe is simulated,and the change relations of stress,strain and ovality in the process of continuous rolling are obtained.According to different pass processes,the metal deformation law,stress-strain,rolling force and cross-section shape of steel pipe in the process of continuous rolling are analyzed,and the criteria for judging the full deformation of metal in the pass are put forward,Under the condition of the same total deformation and the same pass design,the reduction is distributed,rolled in 3,4,5 and 6 stands(passes)respectively,and the deformation law is compared;Further analysis,on the basis of sufficient deformation,reduce the number of passes,and obtain a reasonable number of continuous rolling processes(stands);(3)Experimental study on hot continuous rolling of seamless steel pipeWith the help of the existing research group Φ 50 continuous rolling mill and a plant Φ 165 continuous rolling mill,combined with the results of mathematical modeling and numerical simulation analysis,the outer diameter,wall thickness and torque of steel pipe collected in the experiment are studied,so as to provide experimental basis for studying the sufficiency of metal flow deformation.Through theoretical research,simulation and experimental research,this paper obtains the basic law of the sufficiency of continuous rolling deformation,which is basically consistent with the experimental results.