Patent ID: 8918199

Claim:
A method for controlling the cooling of a vertically moving metal strip in a cooling section of a continuous processing line which sprays in a plurality of spray zones onto the strip a liquid or a mixture consisting of a gas and a liquid, the cooling being dependent on cooling parameters including the temperature, speed and characteristics of the stream of cooling liquid, the method comprising: controlling the cooling parameters in a plurality of spray zones such that a vapor film is maintained at the surface of the hot strip, controlling a cooling capacity across the plurality of spray zones by adjusting one or more of the cooling parameters in one or more of the spray zones while maintaining the vapor film at the surface of the strip in each spray zone, wherein successive ones of the spray zones are arranged in the direction in which the strip moves, wherein a first cooling capacity in a first of the successive ones of the spray zones is controlled to be different than a second cooling capacity in a second of the successive ones of the spray zones, and adjacent ones of the spray zones are distributed over a width of the strip, wherein the temperature of the cooling liquid for each adjacent one of the spraying zones is adjusted over the width of the strip.