Section steel pipe - galvanized square pipe

Galvanized square pipe from the production process is divided into hot galvanized square pipe and cold galvanized square pipe. It is precisely because the processing of these two galvanized square pipes is not the same that they have many different physical and chemical properties. In general, there are many differences in strength, toughness and mechanical properties.

Hot-dip galvanized square pipe

Hot-dip galvanized square tube: It is a square tube welded after the use of steel plate or steel strip crimping, and on the basis of this square tube, the square tube is placed in the hot-dip galvanized pool after a series of chemical reactions. The production process of hot-dip galvanized square pipe is relatively simple, and the production efficiency is very high, the varieties and specifications are also many, and the equipment and funds required for this kind of square pipe are very little, which is suitable for the production of small galvanized square pipe manufacturers. However, in terms of strength, the strength of this steel pipe is far lower than that of seamless square pipe.

Cold galvanized square pipe

The cold galvanized square pipe is to use the principle of cold galvanized on the square pipe used to make the square pipe have anti-corrosion performance. Different from hot-dip galvanized coating, cold galvanized coating is mainly anti-corrosion through the electrochemical principle, so it is necessary to ensure that the zinc powder is in full contact with the steel, resulting in electrode potential difference, so the surface treatment of steel is very important.

Difference between hot and cold galvanizing

Galvanized square pipe has two categories: hot-dip galvanized square pipe and electric galvanized square pipe. Hot-dip galvanized square pipe has wet method, dry method, lead-zinc method, REDOX method and so on. The main difference between different hot dip galvanizing methods is what method is used to activate the surface of the pipe to improve the quality of galvanizing after the acid dip 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 of electrogalvanizing is very smooth and compact with uniform structure. Good mechanical properties and corrosion resistance; The zinc consumption is 60% ~ 75% lower than that of hot dip galvanizing. Electrogalvanizing has a certain complexity in technology, but this method must be used for single-sided coating, double-sided coating with different thickness of internal and external surface coating, and thin-wall pipe galvanizing.