How to improve the appearance of galvanized angle steel

      The galvanized coating on the surface of galvanized angle steel has advantages such as being thin and uniform, aesthetically pleasing, and having strong zinc adhesion. An attractive galvanized coating enhances the grade of the angle steel product. So, what measures can be taken to improve the appearance of the coating surface?

      Measures for Forming Zinc Spangles on Galvanized Angle Steel:
The size of zinc spangles increases with the rise in the mass concentration of the Zn solution and decreases with the increase in the solidification speed of the Zn coating. Generally, after the surface of the galvanizing tank is treated with an aqueous solution, the size of the zinc spangles should be controlled by managing the cooling rate above the zinc pot. This helps produce galvanized angle steel with fine zinc spangles. Additionally, in large-scale continuous hot-dip galvanizing production lines for strip steel, spraying a mixture of water-steam or water-air onto the liquid zinc layer can also achieve fine zinc spangles.

        Measures to Prevent the Formation of Wrinkle Patterns on Galvanized Angle Steel:
During the galvanizing process of angle steel, wavy flow patterns resembling wrinkles from the zinc pot often appear on the surface. This is mainly caused by air knife operations, airflow-induced vibrations in the strip steel, and irregular flow of zinc in the coating. The occurrence of these wrinkle patterns can be prevented by appropriately controlling the wiping conditions of the air knife, wiping pressure, the distance from the nozzle to the steel, and the height=100% of the nozzle above the zinc liquid surface.


Using a Dual Zinc Pot:
        To avoid surface defects caused by dross adhering to the surface of galvanized angle steel, an additional zinc pot can be installed in the production unit. This allows a dedicated zinc pot to be used for producing galvanized angle steel, minimizing the amount of dross generated after switching zinc solutions. Production can thus proceed under stable zinc liquid conditions, reducing the number of dross spots adhering to the surface of the galvanized angle steel and producing products with superior appearance quality.http://www.hnftsteels.com