COOLING ANALYSIS MODEL FOR HOT ROLLED STEEL SHEET AND METHOD OF ESTIMATING PROPERTIES OF HOT ROLLED STEEL SHEET USING THE SAME

摘要

A cooling analysis method of a hot rolled steel sheet that is faster and more stable than an existing cooling analysis method of the hot rolled steel sheet is provided, and a method for estimating properties of the hot rolled steel sheet using the cooling analysis method of the hot rolled steel sheet is provided. A method for estimating properties of a hot rolled steel sheet comprises: a first step(11) of dividing the total length of a hot rolled steel sheet into at least two minute sections in the longitudinal direction to measure and calculate cooling information; a second step(12) of measuring cooling information of a finishing delivery temperature measuring section and a coiling temperature measuring section in the divided minute sections; a third step(13) of setting an initial value of a heat transfer correcting coefficient; a fourth step(14) of calculating a phase transformation of the hot rolled steel sheet; a fifth step(15) of obtaining an analytic solution by a cooling analysis method; a sixth step(16) of obtaining a difference between a temperature at the coiling temperature section measured in the second step and a temperature of the coiling temperature section calculated by the analytic solution of the fifth step; and a seventh step(17) of confirming whether the second to sixth steps have been performed by a final minute section divided in the first step. The method comprises the step of repeatedly performing the fourth to sixth steps if the temperature difference is higher than 1 deg.C in the sixth step. The method further comprises the step of adjusting and renewing the heat transfer correcting coefficient if the temperature difference is higher than 1 deg.C in the sixth step. The method comprises the step of repeatedly performing the second to sixth steps with respect to a next minute section in the seventh step if a process of estimating properties of the hot rolled steel sheet is not proceeded by the final minute section divided in the first step.