The Study On Plate Mill Shape Control System And Model

Shape is one of the most important quality indicators of plate and is the key factor of the market competitive power. Shape control technology has been become one of the core technologies of plate production and is the current emphasis and the hot spot of research and development.Recent years, as the plate mill getting wider and the plate thickness control technology getting perfect, Plate shape problem has been becoming increasingly evident. Meanwhile the heavy draft and rolling in low temperature were adopted in the rolling technology, rolling force was increased significantly, so shape problem become more seriously. Plate control system was studied systematically and deeply, an online application plate shape model was developed in this paper. The main work was shown as following:(1) The plate mill shape control system and Plate mill process control system structure and function were analysised. Functions, methods, strategy, calculation process of plate mill shape control system setting calculation were studyed.(2) The mathematieal models of roll system elastic deformation were set up, discrete element method were used to analysis rolls system elastic deformation. Work roll and backup roll elastic deflection were caculated by integration method with differential form. Flattening between rolls and work roll flattening caculation were modified with exponential smoothing to ensure that the elastic deformation of the roll system accuracy.(3) Roll temperature field and thermal expansion model were built. In this model, roll surface equivalent heat transfer coefficient and heat transfer under the combined effect of a variety of boundaries conditionswere caculated with Fourier series; work rolls and backup rolls temperature field under the action of the boundary conditions were calculated with two-dimensional finite difference method. Roll thermal expansion were caculated on the base of rolls temperature field.(4) Roll wear model was established. The contact arc length, the flattening arc length between rolls and the roll diameter of were considered in this model, meanwhile, the influence of the distance between calculated points and the edge of wear area were considered.(5) A calculation software was programmed by the established shape model. The shape model had the advantages of comprehensive consideration, simple calculation and versatile. The research in this paper had foundad for the plate mill model Improvement and development.