2.The production of hot-dip galvanized tubes involves reacting molten metal with the iron substrate to form an alloy layer, thereby integrating the substrate with the plating. The process begins with pickling the steel tube to remove iron oxide from its surface, followed by cleaning in tanks containing ammonium chloride or zinc chloride aqueous solutions, or a mixture of both. The tube is then sent to the hot-dip galvanizing tank.
3.Hot-dip galvanizing boasts advantages such as uniform coating, strong adhesion, and long service life. Cold galvanizing, also known as electroplating, encompasses various processes. In brief, it involves cleaning, electroplating, and passivation. One type of passivation is color passivation, which gives the cold-plated tube its color. Steel diving boards undergo zincate galvanizing, with passivated surfaces appearing red, green, or slightly yellow (Cr+6 results in red, Cr+3 in green). The appearance of purple indicates a loose passivation film layer. A simple test is to rub the surface of the part with a finger several times; the color should not change. The fundamental difference lies in the coating thickness: electro-galvanized coatings are typically only 20 to 30 micrometers thick, while hot-dip galvanized coatings are generally around 100 micrometers thick. The specified thickness for hot-dip galvanized coatings on steel diving boards is usually around 200 micrometers. However, coating thickness varies depending on the process used.
Post time: 2025-01-06 17:56:02