Hot-dip galvanized steel pipe: reacts a molten metal with an iron matrix to produce an alloy layer, thereby combining the substrate and the plating layer. Hot-dip galvanizing is to pickle the steel pipe first, in order to remove the iron oxide on the surface of the steel pipe, after pickling, it is washed by ammonium chloride or zinc chloride aqueous solution or a mixed aqueous solution of ammonium chloride and zinc chloride, and then fed. Hot dip plating tank.
Hot-dip galvanizing has the advantages of uniform plating, strong adhesion and long service life. The complex physical and chemical anti-galvanized steel pipe of the hot-dip galvanized steel pipe base and the molten plating solution shall form a corrosion-resistant structure of a zinc-iron alloy layer. The alloy layer is integrated with the pure zinc layer and the steel pipe base. Therefore, its corrosion resistance is strong.Hot-dip galvanized seamless steel pipe: the galvanizing amount is very small, only 10-50g/m2, and its corrosion resistance is much worse than that of hot-dip galvanized pipe. Regular galvanized pipe manufacturers use quenched galvanized pipes as water and gas pipes. The galvanized layer of the cold-galvanized steel pipe is an electroplated layer, and the zinc layer and the steel pipe matrix are independently layered. The zinc layer is thin, and the zinc layer is simply attached to the steel pipe base and is easy to fall off. Therefore, its corrosion resistance is poor. In newly built houses, the use of cold-galvanized steel pipes as water supply pipes is prohibited.
The difference between galvanized pipe and seamless pipe:
1. Efficient and environmentally friendly, non-toxic, non-polluting, non-corrosive, not only has the function of pickling, corrosion and fog suppression, but also has the effect of derusting and high-efficiency degreasing. It does not produce toxic or harmful substances during use, which reduces air pollution, is beneficial to the health of operators and improves the working environment of the workshop.
The existing pickling process has large consumption of hydrochloric acid, large acid mist, and short waste acid discharge cycle, and the product can be recycled after being added in a small amount during use, and can be used in the acid during use. Most of the ferrous chloride is converted into iron oxide and precipitated, which greatly prolongs the discharge cycle of the waste liquid.
2. There is no “over-etching” and “rust embrittlement” in the process of derusting. There is no “weight loss” phenomenon when steel materials are immersed for a long time.
3. Strong derusting ability, good effect, fast speed (descaling speed can be adjusted according to needs) General floating rust can be removed in about 5 minutes, significantly better than the current pickling process.
4. The workpiece after descaling with this product has a strong rust-removing adhesion to the zinc layer during galvanizing. The finish is good, and it is obviously superior to the pure hydrochloric acid pickled workpiece.
5. The cost of descaling is lower than the cost of existing pickling (the product can be extended for more than four times after adding this product in the acid solution).
6. The derusting speed can be adjusted in the range of 1min-60min. Generally, the floating rust can be removed within 3 minutes, and the heavy rust can be removed within 30 minutes. Depending on the size of the steel surface, the degree of corrosion and the number of steel grades, the rust of 20-100 tons of material can be removed per ton of rust removal liquid.