Patent ID: 8634953

Claim:
A method for controlling flatness of a stainless steel strip during movement of the strip in a direction of strip movement after annealing in a finishing line, the strip having a width transverse to the direction of strip movement, comprising: feeding the strip sequentially, in the direction of strip movement, through a first cooling station, a second cooling station, a temperature measurement station, a third cooling station, and a flatness control station, in the first cooling station, cooling the strip by feeding at least one cooling medium onto a surface of the strip in a plurality of spray jets distributed transversely of the direction of strip movement over the whole width of the strip, adjusting an amount of the cooling medium fed in the first cooling station in accordance with predetermined data based on a desired temperature of the strip for flatness, in the second cooling station, cooling the strip by feeding at least one cooling medium onto a surface of the strip in a plurality of spray jets distributed transversely of the direction of strip movement over the whole width of the strip, in the temperature measurement station, measuring temperature of the strip, comparing the measured temperature of the strip with the desired temperature of the strip and, if the measured temperature differs from the desired temperature, cooling the strip in the third cooling station by feeding at least one cooling medium onto a surface of the strip in a plurality of spray jets distributed transversely of the direction of strip movement over the whole width of the strip, in the flatness control station, measuring flatness of the strip at a plurality of mutually contiguous locations distributed transversely of the direction of strip movement utilizing a roll-type control device that comprises a rotatable shaft and flatness control units that are contiguously mounted on the rotatable shaft so that the flatness control units extend over at least the whole width of the strip, and controlling the cooling at the first, second and third cooling stations employing a computing device that is electrically connected to the temperature measurement station and the flatness control station.