NON-GALVANIZING GENERATION PREVENTIVE METHOD IN GALVANIZING PROCESS

摘要

PROBLEM TO BE SOLVED: To provide a method to prevent non-galvanizing to be generated in the galvanizing process by controlling the quantity of iron powder in the rolling oil stuck to the steel plate after the cold rolling. SOLUTION: In the galvanizing process of a steel sheet, the quantity of iron powder in the rolling oil stuck to the steel sheet before galvanizing is controlled to be <=200mg/m<2> . In the galvanizing process of steel sheet, rolling is performed with the mean roughness (Ra) of 0.3-0.58μm at the center line of a work roll in the cold rolling process which is the pretreatment of the galvanizing process.