Hot-dip galvanizing

Hot-dip galvanized steel pipe is molten metal reacting with the iron matrix alloy layer, so that the substrate and coating combination of both. Galvanized pipe is first pickled, the steel surface in order to remove iron oxide, after pickling, cleaning tank by mixing an aqueous solution of ammonium chloride or zinc chloride and zinc chloride or ammonium chloride solution, and then into hot dip tank. Galvanized with coating uniformity, strong adhesion, long life and other advantages. Hot dip galvanized steel substrate with molten bath complicated physical, chemical reactions, the formation of corrosion-resistant zinc-iron alloy structure closely layer. Alloy layer and layer of pure zinc, steel base blend. Therefore it resistant to corrosion.

Key Characteristics and Benefits

• Superior Corrosion Resistance: A metallurgical bond forms between the zinc and steel, creating a “sacrificial anode” that protects the steel even if the surface is scratched.
• Double Protection: Covers both internal and external surfaces with a thick, uniform zinc layer, unlike pre-galvanized options.
• Durability & Longevity: Offers a 6-month to two-year maturation period, forming a protective zinc patina that enhances its life cycle.

Hot-Dipped vs. Cold/Electro-Galvanized

Hot-dipped provides a much thicker coating (45-85 mú) compared to electro-galvanized. Cold-galvanized is often limited to the outside surface, has lower rust resistance, and is generally not suited for, or is banned for, high-pressure water/gas pipe usage.