| 摘要 |
PURPOSE: A method for supplying strict numerical model into coiling temperature control model considering phase transformation and thickness directional heat transfer and supplying proper coiling temperature and injection water bank number required for controlling phase transformation fraction at coiling time based on the model is provided. CONSTITUTION: In a method for controlling temperature of hot rolled strip in a hot rolling line in which finish rolling mill, run-out table and down coiler are sequentially arranged, thermometers are installed between the rear end of the finishing rolling mill and the front end of the down coiler, the cooling control method of high carbon hot rolled strip considering phase transformation comprises step (a) of calculating coiling temperature and phase transformation by inputting an arbitrary virtual injection water pattern using strict temperature calculation equation from a target FDT (finishing delivery temperature) of strip; step (b) of changing the virtual injection water pattern by comparing calculated phase transformation fraction with target phase transformation fraction at coiling time; step (c) of finding the optimum coiling temperature and optimum injection water pattern so that a difference between the calculated phase transformation fraction and target phase transformation fraction by repeating the steps (a) and (b); step (d) of obtaining learning coefficient of an existing temperature model corresponding to the optimum coiling temperature and optimum injection water pattern; and step (e) of performing feed forward control using the optimum learning coefficient and optimum coiling temperature.
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