classification
Galvanized square tube is divided into hot galvanized square tube and cold galvanized square tube from the production process. It is precisely because the processing of these two galvanized square tubes is different that they have many different physical and chemical properties. In general, they are different in strength, toughness and mechanical properties.
Hot dip galvanized square tube: it is a square tube that is welded after the steel plate or steel strip is rolled and formed, and is formed after a series of chemical reactions in the hot dip galvanized pool on the basis of this square tube. The production process of hot-dip galvanized square tube is relatively simple, and the production efficiency is very high, and there are many varieties and specifications. This square tube requires few equipment and funds, which is suitable for the production of small galvanized square tube manufacturers. But in terms of strength, the strength of this kind of steel pipe is far lower than that of seamless square pipe.
Cold galvanized square pipe
And the cold galvanized square tube is to use the principle of cold galvanizing on the square tube used to make the square tube have anti-corrosion performance. Different from hot galvanizing, cold galvanizing coating mainly uses electrochemical principle to prevent corrosion, so it is necessary to ensure full contact between zinc powder and steel to generate electrode potential difference, so steel surface treatment is very important.
Difference between hot and cold galvanizing
Galvanized square tube includes hot galvanized square tube and electrogalvanized square tube. The hot-dip galvanized square tube includes wet method, dry method, lead zinc method, oxidation reduction method, etc. The main difference between different hot dip galvanizing methods is what method is used to activate the surface of the pipe body to improve the quality of galvanizing after the acid pickling cleaning of the steel pipe. At present, dry method and redox method are mainly used in production, and their characteristics are shown in the table. The surface of the zinc layer is very smooth, dense and uniform; Good mechanical properties and corrosion resistance; Zinc consumption is 60%~75% lower than that of hot galvanizing. Electrogalvanizing has certain technical complexity, but it must be used for single-sided coating, double-sided coating with different coating thickness on internal and external surfaces, and thin wall tube galvanizing.
Post time: Dec-23-2022