Patent ID: 11577306

Abstract:
In a first cooling zone (21) on an upper side of a vertical section (20), an air-water ratio A1/R1 defined by an amount of water R1 (L/min) and an amount of air A1 (L/min) per one cooling spray nozzle is set to 10 or more, an impinging pressure of cooling water colliding with the surface of a slab (1) from the cooling spray nozzle is set to 12 gf/cm2 or more, a cooling intensity W1×t1 defined by a cooling water density (W1) (L/min/m2) and a passing time t1 (min) of the first cooling zone (21) is 350 or more, and a recuperating time from having passed through the first cooling zone (21) until reaching a bent section (30) is set to 0.5 min or more.