Method for controlling strip temperature by adjusting a strip target temperature in a continuous annealing furnace

摘要

PURPOSE: A method for controlling the sheet temperature by adjusting the target sheet temperature of a continuous annealing furnace is provided which controls the temperature of a steel sheet when a thickness of the steel sheet continuously processed and an annealing temperature are varied in the continuous annealing furnace. CONSTITUTION: The method comprises a first step (ST11) of receiving operation information including thickness, width, target sheet temperature and tolerance of a steel sheet to be processed; a second step (ST12) of adjusting the received target sheet temperature; and a third step (ST13-ST19) of changing a temperature of the furnace by calculating a furnace temperature set value and a furnace temperature changing time point according to a numerical formula model for controlling the sheet temperature after the adjusting step of the target sheet temperature, and changing a sheet passing speed by calculating the sheet passing speed and the speed changing time point, wherein the second step is characterized in that a target sheet temperature obtained according to the steel sheet is controlled within the range of tolerance, and the adjusted target sheet temperature is adjusted so that a change amount between a furnace temperature set by being used in the numerical formula model determining a furnace temperature and a sheet passing speed and a present furnace temperature is minimized.