Hot dip galvanized pipe is molten matrix metal and the reaction of the iron alloy layer so that the substrate and coating combination of both. Hot dip galvanized pipe is first pickled, on the steel surface in order to remove iron oxide, after pickling, by mixing the aqueous solution tank for cleaning solution or ammonium chloride or zinc chloride, and then into a hot-dip plating bath. Galvanized with coating uniformity, strong adhesion, long life, and other advantages. Steel substrate occurs with molten bath complex physical, and chemical reactions, the formation of corrosion-resistant zinc-iron alloy structure closely layer. Alloy layer and a layer of pure zinc, steel base blend. Therefore it is resistant to corrosion.
Hot dip galvanizing process:
Preparation – pickling – washing – solubilization – hot-dip zinc – Cooling – passive – cleaning – sorting – recheck – packaging – storage
When the temperature is too low, zinc was poor mobility, coating thickness, and uneven, prone to sagging, and poor visual quality; temperatures are high, good fluidity liquid zinc and zinc from the workpiece an easy solution to reduce the phenomenon of sagging and wrinkled skin happen, strong adhesion, coating thin, good appearance, high production efficiency; But the temperature is too high, the workpiece and zinc pot iron loss seriously, producing a large zinc slag, affecting dip zinc coating quality, large consumption of zinc, not even plating. At the same temperature, the dip time is long, and the coating thickness is. Different temperatures, require the same thickness, and the length of time required for the high-temperature dip.