Numerical Simulation And Technological Research On Differential Thickness Rolling Of Thick Steel Plate

Thick plate steel,as an important steel variety,is widely used in all aspects of national economic construction.How to overcome the problem of loose internal structure,coarse grain and segregation of continuous casting slabs to produce high quality thick steel products under low compression ratio to ensure the quality and performance of their products,especially the intrinsic quality of special thick plate products,has been plagued by the plate production enterprises and rolling technology research needs to focus on an important issue.This paper proposed to improve the poor conditions of thick steel plate rolling thick rolling technology,overcome the thick blank when rolling bite limit,impact torque decreases head impact,increasing single pass reduction,improve the deformation and permeability,and improve product performance.The difference on the basic theory of thick rolling based on the finite element software ABAQUS is applied to establish plate thickness difference rolling model,obtained by numerical simulation technology,equipment,rolling conditions on the deformation process of the stress and strain distribution,metal flow law and deformation of the rolling load and the influence of the law,in order to improve the rolling conditions,improve the internal performance of thick specification for steel products,further enrich the application field of variable thickness rolling technology,has important theoretical and practical significance.The main contents of this paper include:(1)The differences between differential thickness rolling process and conventional rolling process is analyzed and and the basic theory of differential thickness rolling is expounded.Based on the deformation,kinematics and mechanical conditions of the wedge rolling process,the bite angle,the neutral angle,the contact arc length and the front slip formula in differential thickness rolling process are deduced to determine the rolling speed and the taper rolling time closely related to the differential thickness rolling control.(2)Based on the basic theory of conventional rolling AGC,the AGC model of variable thickness rolling process is studied,and the thickness control method under differential thickness rolling process is developed.Based on the AGC model of the medium and heavy plate mill,the various AGC models commonly used in the rolling are analyzed,theoretically deduced and compared.The realization method of thickness control in differential thickness rolling process has laid the theoretical basis for the development and application of AGC model with variable thickness for the plate rolling process.(3)Based on the ABAQUS finite element software,the dynamic coupling process of the three-dimensional conventional rolling and differential thickness rolling process of the plate is simulated by the display dynamic algorithm.Through numerical simulation and theoretical analysis,the stress and strain distribution,the law of metal flowand its influence on the rolling load under different rolling conditions and different rolling process parameters(reduction rate,thickness,coefficient of friction,etc.)were studied.The improvement of bite condition of differential thick rolling is analyzed,and the influence law of differential thickness rolling process on deformation and permeability of heavy gauge steel plate is obtained,and the relationship between the process conditions of differential thickness rollingand the deformation and permeability was established.(4)Based on the production process,the precise setting and control model of the differential thickness rolling of the thick gauge steel plate are established.The performance of the steel plateand the force parameters of the rolling process are analysed and calculated by using the differential rolling model.The actual production situation is compared to verify the accuracy and effectiveness of the differential rolling modeland the effect of differential rolling control on the permeability of steel plate.A production process of differential thickness rolling suitable for engineering application is developed to achieve the practical application of the technology and improve the performance of thick steel products.The research results of this subject can enrich the application of variable thickness rolling technology and improve the inherent quality control of thick steel products,which has important theoretical and practical significance.