METHOD OF CONTROLLING FINISHING MILL ENTRY TEMPERATURE BY SETTING TARGET INDUCTIVE HEATER DELIVERY TEMPERATURE USING ACTUAL RESULTS OF FINISHING MILL ENTRY TEMPERATURE

摘要

PURPOSE: To provide a method of controlling finishing mill entry temperature in mini-mill process, the method for improving threadability by controlling a target inductive heater delivery temperature according to actual finishing mill entry temperature values, thereby increasing an average of finishing mill entry temperature and improving a hitting ratio of finishing mill entry temperature. CONSTITUTION: In a bar finish rolling process of a mini-mill, the method of controlling finishing mill entry temperature in mini-mill process comprises a step of obtaining a mean value by measuring finishing mill entry temperature values of a preceding bar in realtime; and a step of subtracting a temperature deviation of finishing mill entry temperature from a target inductive heater delivery temperature value of a succeeding bar if there is a deviation between the mean value and a target finishing mill entry temperature value so that the finishing mill entry temperature is approximated to the target inductive heater delivery temperature value, wherein a limit voltage of an inductive heater is controlled to 1,400 V to promptly change inductive heater delivery temperature, and wherein if a temperature deviation between the measured finishing mill entry temperature values and the target finishing mill entry temperature value is 10 deg.C or more, the temperature deviation is subtracted from the target inductive heater delivery temperature value, and if the temperature deviation between the measured finishing mill entry temperature values and the target finishing mill entry temperature value is less than 10 deg.C, 10 deg.C is subtracted from the target inductive heater delivery temperature value.