The inner diameter of the 1.2-inch galvanized pipe is about 32mm and the outer diameter is about 42.25mm
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Instructions for use of galvanized pipe
Commonly said Galvanized pipes, the purpose of galvanized pipes. The iron pipes used for gas and heating are also galvanized pipes. Galvanized pipes are used as water pipes. After several years of use, a large amount of rust and scale will be generated in the pipes. The yellow water flowing out will not only pollute the sanitary ware, but also contain contaminants. Bacteria that breed on the rough inner wall and rust cause excessive heavy metal content in the water, seriously endangering human health.
Hot-dip galvanized pipe
Hot-dip galvanized pipe reacts molten metal with the iron matrix to produce an alloy layer, thereby combining the matrix and the coating. 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 cleaned in an aqueous solution of ammonium chloride or zinc chloride or a mixed aqueous solution of ammonium chloride and zinc chloride, and then sent to in a hot dip plating tank.
Hot-dip galvanizing has the advantages of uniform coating, strong adhesion, and long service life. The hot-dip galvanized steel pipe matrix undergoes complex physical and chemical reactions with the molten plating bath to form a corrosion-resistant zinc-iron alloy layer with a tight structure. The alloy layer is integrated with the pure zinc layer and the steel pipe matrix, so it has strong corrosion resistance.
Cold-dip galvanized pipe
Cold-dip galvanized pipe is electro-galvanized. The amount of galvanizing is very small, only 10-50g/m2. Its corrosion resistance is better than that of hot-dip galvanized pipe. Very different. Regular galvanized pipe manufacturers, in order to ensure quality, most do not use electro-galvanizing (cold plating). Only small businesses with small scale and old equipment use electro-galvanizing, and of course their prices are relatively cheaper.
The Ministry of Construction has officially announced that cold-galvanized pipes with backward technology will be phased out and cold-galvanized pipes are not allowed to be used as water and gas pipes. The zinc layer of cold-dip galvanized steel pipe is an electroplated layer, and the zinc layer is layered independently from the steel pipe matrix. The zinc layer is thin, and the zinc layer simply adheres to the steel pipe matrix and falls off easily. Therefore, its corrosion resistance is poor. In new residential buildings, it is prohibited to use cold-dip galvanized steel pipes as water supply pipes.
Reference: Galvanized steel pipe--Baidu Encyclopedia