The influence of work roller diameter on shape of strip in stainless steel cold strip rolling process with numerical simulation method

摘要

In order to study the effects of work roller diameter on shape of strip in cold strip rolling process, the ANSYS/LS-DYNA software was employed to simulate rolling process of 2mm thickness stainless steel. It is found that the average of stress decrease along with the increasing diameter of the work roller. But this variation is about 1%. The stress-strain curve go more steady and the shape of strip become better along with the decreasing of the work roller diameter. In this paper the three kinds of rolling process will produce tiny waves edge. The waves edge was the most obvious when the work roller diameter is 60mm. The cold rolling is significant production process in the iron and steel industry, which has product added high value and intense market competition. Strip flatness flaw is one of the main problems of quality in strip rolling. As the modern industry developing rapidly, more and more high quality cold strip products are needed now. So the research of shape control is important from the view of both theory and production. The deformations in consideration not only include elastic deformation and plastic deformation but also springback. It is very difficult to analyse. In order to solve this problem, finite element method was employed to simulate rolling process. It brings forward theory foundation and method [1] for establishing the mathematical mode of shape control. In order to obtain detailed solutions regarding the influence of work roller diameter on shape of strip in stainless steel cold strip rolling process, the 3-D elastic-plastic finite element method(FEM) have been employed in the last few decades. Some researchers have simulated such as the influence of tension [2] on shape of strip, the influence of rolling-force [3,4]on shape of strip and so on. An important problem is the study model was mostly set up based on experiment rolling mill which with small size far from the scale of production. On the other hand the simulate strip thickness mostly more than 5mm. The research work for cold rolled sheet thickness under 3mm is inadequate at present. In order to make better numerical simulation result in finish rolling and get more reasonable rolling parameters, the thin strip rolling process of 4-high rolling mill is simulated and analyzed by using 3-D elastic-plastic FEM with software ANSYSLS-DYNA. This method can describes the whole process of metal deformation from nip to steady rolling. The postprocessor analyze the distributing characteristic and the changing orders of stresses and strains, as well as maximal stress fields and maximal strain fields. By these way to discuss the influence of work roller diameter on shape of strip in stainless steel cold strip rolling process.