METHOD OF MANUFACTURING HOT-ROLLED STEEL SHEET

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing method of a hot-rolled steel sheet excellent in surface property without scale defects by executing descaling by jetting high-pressure water jet from two rows of nozzles to high silicon and high nickel steel containing Si and Ni of 0.2-2.0 wt.% respectively in a hot-rolling stage. SOLUTION: By using a descaling device on which two rows of headers 4a, 4b are arranged at a proper interval in the advancing direction of the line and setting the collision pressure for descaling at >=3 kgf/cm2 and the attack anglesθof the descaling nozzles of each row respectively at 0-5 deg., descaling is executed.