CORROSIVE PREVENTION METHOD OF HOT ROLLED STEEL SHEET BY NEUTRALIZING WASHING SOLUTION AND SYSTEM THEREOF

摘要

PURPOSE: Provided is a corrosive prevention method of hot rolled steel sheet by neutralizing washing solution which prevents steel sheet from being corroded in a washing process when decreasing line speed so that it helps to raise product quality. CONSTITUTION: The corrosive prevention method of hot rolled steel sheet by neutralizing washing solution comprises the steps of: (i) checking the speed of line in a hot rolling process and then checking the concentration of pH and the speed of line when the speed is under the appropriate speed to examine; (ii) when the checked pH value is low, opening a storage part for sodium hydroxide and a connected valve to raise pH value and decrease corrosion reaction speed in washing; and (iii) checking the speed of line again and running sequence to reach the appropriate speed.