Analysis and measures of rolling marks on hot galvanizing leveler

Hot-dip galvanized sheet is widely used in industries, such as automobiles, home appliances, electronic appliances and construction, due to its good corrosion resistance, processability, weldability, and paint ability. With the development of the automobile industry, the surface quality requirements of automobile steel are gradually improved. However, The galvanized sheet produced on our GJSS 2# galvanizing line often has rolling marks defects, which seriously affects the quality of products. This paper analyzed the physical and chemical features of the defect sample of roller marks on the sheet. Based on the research and analysis, measures such as adding side guide pulleys on the work roll chocks, high-pressure water spray was added to the lower backup rolls when changing rolls, and water barriers were added to the work roll tracks. The results showed that these measures reduced the occurrence of roll marks.