Research On Temperature Control System Of Roller Tunnel Furnace

The roller tunnel furnace in industrial is a typical intricate controlled object.It includes various changes thermodynamics,chemistry,physic,in the normal process.The characteristic of the heating furnace is nonlinear,multivariable,strong coupling,large lag,etc.The furnace heats the slab,and the temperature uniformity of slab at the outlet must meet the requirements of the rolling.Currently,in order to achieve the goal,we use various control methods for furnace temperature controlled.Thus,temperature control is crucial.In this thesis,the roller tunnel furnace temperature control system as the background has been introduced and analyzed,and focused on the tunnel furnace process,function,structure,process parameters and etc.Thin slab continuous casting and rolling production line is a typical DSP technology process in TISCO.Heating process control and the slab heating quality is a key factor which directly affects the level of energy consumption of hot rolling process,so it is very important to understand the principles of billet heating and thermal equilibrium process.Casting speed has been analyzed respectively when the maximum,normal,and the minimum heat exchange information through heat balance diagram,that determines range in the process within the allowable temperature range ± 10? and the heating times of three cases which are respectively 8.5 minutes,13.8 minutes and 22.0 minutes.It is considered that heating too long would waste fuel,and increase production cost,and increase the amount of iron oxide.The analysis conclusion which laid a foundation for the design of the furnace temperature control system.Through the analysis and comparison to the single and double cross limiting control,it has been established that a double-cross limiting temperature control mode and ensured the full fuel combustion,and reduced emissions of polluting gases,and improved the stability of the air-fuel ratio.Thus it has been solved that the original control method imbalance,excess air and fuel flow system acted each other to the oscillation caused.And we have achieved a stable control of the furnace temperature to ensure the slab heating equality.