PURPOSE: To prevent the generation of meandering and drawing of the steel sheet in the cooling zone of the continuous annealing equipment for sheets and to obtain the desired quality of the steel sheet obtd. by annealing.
CONSTITUTION: The adequate temp. difference ΔT between the sheet temp. and furnace temp. which can confine the total crown tc of the rolls in the furnace of slow cooling equipment 3b within the crown threshold value for assuring passability is determined and the computation to predict the sheet temp. progress of the slow cooling equipment 3b by a radiation heat transfer model equation is executed. Whether the outlet sheet temp. of the slow cooling equipment 3b is at the target sheet temp. determined for the material of the steel sheet or not is decided from the result of this calculation. Whether the temp. difference progress of the slow cooling equipment 3b determined by the prediction calculation is within the range of the above-mentioned adequate temp. difference ΔT or not is further decided if the decision thereof is true. The sheet temp. in the outlet of the rapid cooling equipment 3a and the furnace temp. of the slow cooling equipment 3b are determined only when this decision is true. The control of the cooling capacity of the above-mentioned rapid cooling equipment 3a and the control to set the furnace temp. of the slow cooling equipment 3b are thus executed.
YOSHIOKA OSAMU
SHIMADA TAKASHI
| JPS63179025A | 1988-07-23 |