In a cooling section having a plurality of coolant outlets, the coolant outlets are supplied with the coolant via transmission lines and a mutual main line. Individually opening and closing valves are disposed in the transmission lines. An automation device of the cooling section opens and closes the valves at valve-specific opening and closing times during the normal operation of the cooling section in order to apply coolant to the rolling stock according to a quantitative target coolant course. During the determination of the opening times, the automation device considers a respective valve-specific characteristic. In calibration operation of the cooling section, the respective characteristic is initially determined at least for some of the valves by opening and closing the respective valve, and detecting the chronological course of the quantitative coolant flow effected thereby by a measuring arrangement disposed in the main line.