The Simulation Research Of Shape Control Efficiency Function On Cold Rolling Mill

The cold rolling strip is still the essential basic material in the national economy nowadays. The new cold rolling mills are usually equipped with a variety of means to control strip shape.In the actual production, sorts of control means were integrated to use at the same time, intending to eliminate bias and get good flatness.The shape control efficiency was used to describe the performances and features of shape control means, as an important part of the cold rolling flatness closed-loop control system. In this paper, UCM mill is the research object to study the shape control efficiency of work roll bending, intermediate roll bending and intermediate roll shift in different conditions, which are main means of shape control measure, using the finite element software MSC.Marc.First, cold rolling strip shape control efficiency model was established, based on elastic-plastic finite element method, to analyze the efficiency of different control means. The effect of shape control efficiency was compared, which was affected by different factors, such as workpiece entry thickness, strip width, front and back tension and so on. Their variation were analyzed according to plenty of examples calculated.Secondly, the strips before cold rolling tend to have a certain cross-sectional shape, due to deformation of the metal during hot rolling. Cold rolling strip transverse thickness curve model was established accoding to cross-sectional curve, to analyze and compare the distribution of transverse thickness and tensile stress at the strip rolling outlet. The shape control efficiency with different cross-sectional is presented by various kinds of control means. The impact was analyzed and studied, which was created by quadratic and four coefficients variation in cross section curve to shape control efficiency.Finally, the function fitting method was applied on the strip to exert different stress field, so that the effect is equivalent to the distribution of internal stress. Cold rolling strip residual stress model was built, and analysis and comparison of different stress field is applied to the strip outlet transverse thickness distribution, tensile stress distribution. In the end different stress field flatness control efficiency of each control means was acquired and impact of changes in the stress field function coefficients regulatory efficiency was studied.In this paper,the research can be applied directly in flatness closed-loop feedback control system,and make the shape control efficiency change with the change of rolling process coefficient dynamically. At last, it can improve the quality of shape control further.