Automation System And Control Strategy For Billet Heating Process

As an important thermal technology equipment in the steel industry, heatingfurnace’s production task is reheating casting billet continuously according to therolling mill rhythm to ensure the reheated billet temperature to satisfy thetechnological requirements of the rolling process. The product quality, consumptionand output are directly related to the automation level of heating furnace.Billet heating is an extremely complicated process. Combustion processcontrol system includes furnace temperature control and pressure control. Thecharacteristics of combustion process have large lag, large inertia, multi-variable,strong coupling, time-varying, nonlinear and its model is too complicated toaccurately establish. Therefore, in the face of such a complicated industrial process,the conventional linear model and simple control method can not satisfy the controlrequirement. Better model must be looked for. Some new control methods andtechniques must be researched.A Walking beam furnace is taken as researching background. Aiming at theactual characteristics of the heating furnace, referencing a much data of furnacelocale, a mode is established with three temperature zones, and a feed-forwardcompensation decoupling network is put forward based on parameter self-adaptiveregulators. A cascade construction is improved as temperature and flow controlsystem. It includes double closed loop control with amplitude cross limit, dynamicair-fuel ratio self-optimizing, and compensation temperature given based on thereheated billet temperature. A fuzzy self-tuning PID parameters regulator is used insingle loop furnace pressure control.Kinds of control methods and self-adaptive decoupling models are simulatedand applied. The results all prove that the combustion control strategy hasoutstanding behave.