PROBLEM TO BE SOLVED: To more reliably and easily remove a bullion attached to a lance. In the method for cooling a top-blown lance according to the present invention, the weighed value of the top-blown lance measured at the end of the (N-1) th (N is an integer of 2 or more) blowing is above the normal temperature. It is higher than the weighed value of the blow lance, and the temperature of the cooling water on the outlet side of the top blow lance during the (N-1) th blow and before the start of the (N-1) th blow. When the maximum value of the product of the temperature difference between the temperature of the cooling water on the outlet side of the top blowing lance, the flow rate of the cooling water, and the specific heat drops below the threshold value, the metal adhering to the top blowing lance becomes It is judged that it has stopped falling off, and at least one of the flow rate or temperature of the cooling water supplied to the top blown lance during or at the end of blowing is determined from the Nth blowing until the attached bare metal falls off. , The control index represented by the product of the temperature difference and the flow rate is controlled to be 1.1 times or more and 3.0 times or less of the maximum value of the control index at the time of normal blowing. [Selection diagram] FIG. 8
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