Development Of An Integrated Simulation System For H-beam BD Hot Rolling

H-beam is one kind of shaped steels with more superior cross-section properties and ratio of strength to weight, which becomes more and more important in national economic construction. H-beam hot rolling is a highly nonlinear plastic large deformation process, which is quite difficult to be described by analytical models. With the development of computer performance, finite element method has been widely used to simulate H-beam hot rolling processes. At present, powerful commercial FEM software, such as ANSYS, ABAQUS, and Marc are always adopted to simulate the rolling processes. On account of universality of these software and complexity of hot rolling processes involving reciprocal and continuous rolling, problems that include complicated jobs in pre-processing, difficulties in re-meshing and inconvenient information extraction in post-processing arise. In order to solve the problems mentioned above, an integrated simulation system specific to H-beam hot rolling processes was designed in this thesis. The development of the system enabled the extraction of instant rolling information and made the information quite clear in the whole processes of hot rolling, which was significant to the improvement of present processes of hot rolling and development of new types of steels. The main research tasks in this thesis are as follows:Based on commercial FEM software ABAQUS/Explicit solver and elastic-plastic finite element method, transient rolling of H-beam in each pass could be simulated. Pre-processing and post-processing were developed by ABAQUS Scripting Interface, and a rolling simulation system was constructed.Take BD rough rolling with reciprocating movement as the subjects, and the system adopted the way of customizing applications, which meant on the basis of CAE users'main window, programs with scripting language Python would be used to establish modules of pre-processing, post-processing and corresponding graphical user interface. In the pre-processing of simulation system, modeling, material property, assembling, seed meshing, contact and boundary condition could be achieved with parametric design, and important process parameters would be input and modified in corresponding graphical user interface, jobs would be submitted automatically for various types medium-sized H-beam in each rolling pass. Programs with re-meshing technique were implemented to solve the problem of mesh distortion caused by large plastic deformation in the inter-pass of the simulation system, which could carry out the detection of steady state, collection of boundaries of work-piece and accurate transmission of parameters like temperature and equivalent plastic strain. In the post-processing of simulation system, users could choose output parameters they wanted, and extraction of instant rolling information in every pass and inter-pass would be completed. Compare the distribution of temperature and data of rolling force in each pass to measured data, and the relative error of surface temperature is less than 5%, data of rolling force basically reflect the tendency, and the system is verified reliably and accurately.