Patent ID: 9061335
Filing Date: 2015-06-23
Classification: B21B

Abstract:
1. A cooling apparatus for hot rolling which is installed on a downstream side of a finishing mill of a continuous hot rolling mill, and cools a steel sheet rolled by the finishing mill while being conveyed, the apparatus comprising: first pinch rolls which, during an interval when the steel sheet fed out from a final stand of the finishing mill moves from a position of the final stand to a position where a surface temperature of the steel sheet reaches 850° C. or less, pinch the steel sheet while applying tension of 3.9 MPa or greater, the first pinch rolls being installed at a position immediately after where the surface temperature of the steel sheet is cooled to 850° C., second pinch rolls being installed at a position where a surface temperature of the steel sheet is from 650° C. to 550° C., third pinch rolls being installed at a position where a surface temperature of the steel sheet is from 450° C. to 350° C., and a rapid cooling unit configured to rapidly cool the steel sheet to a temperature of 850° C. or lower at an immediate rapid cooling zone provided between the final stand and the first pinch roll, wherein the second pinch rolls and the third pinch rolls apply tension of 3.9 MPa or greater between the position of the steel sheet where the second pinch rolls are installed and the position of the steel sheet where the third pinch rolls are installed.