Difference Between Hot-dip Galvanized Pipe And Cold-galvanized Pipe
Posted: Dec 30, 2018
First, the hot-dip galvanized pipe is obtained by reacting a molten metal with an iron matrix to form 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 of JDG line pipe and long service life. Second, cold galvanizing is electroplating zinc, galvanizing is very small, only galvanized on the outer wall (hot-plating - both inside and outside), only 10-50g / m2, its corrosion resistance is much different than hot-dip galvanized pipe. Regular galvanized pipe manufacturers, in order to ensure quality, most do not use electro-galvanizing (cold plating) in seamless steel pipe.
1. Only small businesses with small equipment and old equipment use electro-galvanized steel. Of course, their prices are relatively cheaper. The Ministry of Construction has officially laid down the cold-galvanized pipe with backward technology, and the cold-galvanized pipe is not allowed to be used as water and gas pipe. Third, the galvanized steel pipes currently used are all hot-dip galvanized, and the electric wire grooves used for electrical purposes are cold-galvanized, and the colors have certain differences. The galvanized steel pipes are divided into cold-plated pipes and hot-plated pipes. The former has Was banned, the latter was also temporarily used by the state.
1. Hot-dip galvanizing pipe The hot-dip galvanizing pipe is made by reversing the molten metal and the iron matrix and purchasing the JDG threading pipe alloy layer, thereby combining the substrate and the plating layer.
2. Hot-dip galvanizing is to first pick the steel pipe, in order to remove the iron oxide on the surface of the steel pipe, after pickling, after washing with ammonium chloride or zinc chloride aqueous solution or a mixed aqueous solution of ammonium chloride and zinc chloride, and then Feed into the hot dip plating tank. Hot-dip galvanizing has the advantages of uniform plating, strong adhesion and long service life.
Fourth, cold-galvanized pipe Cold-galvanized is electro-galvanized, the amount of galvanizing is very small, as long as 10-50g / m2, its own corrosion resistance is much worse than hot-dip galvanized pipe.
- The galvanized pipe manufacturer of the track, in order to ensure the quality, the large purchase of JDG threading pipe does not use electro-galvanizing (cold plating). As long as small enterprises with small plans and outdated equipment use electro-galvanized steel, of course, their prices are relatively cheap. At present, the Ministry of Construction has officially laid down the cold-galvanized pipe with backward technology. In the future, it will ban the use of cold-galvanized pipe as water and gas pipe.
- Hot-dip galvanizing and cold-galvanizing are different in the way of operation: one is zinc plated in molten zinc melt at 450-480 degrees, and the other is zinc plated by electroplating or other methods at normal temperature. The hot-dip galvanized zinc layer is superior to cold-galvanized, and has a corrosion-resistant function due to the zinc-iron alloy layer.
- Under normal circumstances, the hot-dip galvanized zinc layer should be thicker, corrosion-resistant to buy JDG threading pipe function is better. The zinc layer of electrogalvanized is thinner and has less corrosion resistance. (Unless the cold-galvanized zinc layer reaches the thick zinc layer) Which one is better? Can't be confused, see what you use.
For example, the supporting wire in the water pipe is still better in electroplating, beautiful, and low in cost; if it is a power tower, it is a big mistake to use electroplating zinc. It should be hot-dip galvanized. Since the hot-dip galvanizing has good corrosion resistance, it can be used for 3 or 4 years.
A worker from a steel pipe company, which is located in China.