The Research Of Slab Reheating Furnace Computer Control System

The furnace is one of the most important thermal equipments in the steel-rolling lineand its manipulation level can directly influence the heating quality, output and energyconsumption of the steel products and the service life of the rolling mill. According thestatus of automation producing of the furnace, a strategy of computer automatic controllevel2which regards the computer supervisor control and the direct digital control（SCC+DDC）as the basic automation and the Distributed Control System as the frameconstruction is put forward in this paper. By using finite difference method of the transientheat conduction, a slab temperature forecasting model, a delay model and a materialtracking model are established and the calculation procedure is provided separately. Theapplication of the integration algorithm of the improved time scale in the pulsecombustion control of the burner is studied. The response speed of the temperature controlcan be improved to reduce the overshooting. Aim at the shortage of the generaldual-crisscross and amplitude limit control system. The variable offset, dual-crisscrossand amplitude limit combustion control system structure is put forward to solve theproblems like the response speed slows down when the load changes. The consumption ofcombustion-supporting air is introduced as the feed forward control variable of thefurnace pressure by which the control hysteresis of the furnace pressure is overcomeeffectively. By simulating the combustion and heating process in which the backgroundcomputation of the heat transfer theory and fluid dynamics in the heating furnace and theforeground model are combined, good guideposts and a satisfied result of saving energyare obtained.