Cold galvanized products are mainly made ??of high -purity zinc, volatile organic solvents and special resin mixture of 3 parts. The amount of zinc in the dry film coating is up to 96%, which is mainly through electrochemical protection to prevent steel corrosion. According to electrochemical corrosion theory, the etching of the electrode potential of the battery has a lower corrosion of the anode. When subjected to erosion coating, zinc as the anode first corrode steel cathode substrate to be protected. Cold galvanizing zinc powder coating is to protect the process of gradually being consumed, but the speed is very slow. The formation of corrosion products, so that the potential difference between the coating and the substrate has decreased, when the film is damaged, once the fresh zinc metal is exposed, the potential difference increases immediately, produce a strong cathodic protection. which can also be described as cold galvanizing of the "self-healing" sex. Its paint mainly through electrochemical principles for corrosion, it is necessary to ensure full contact of zinc powder and steel, generating electrode potential difference, so the steel surface treatment is very important.
Cold galvanizing contains special organic resins, film, which can stop or inhibit water, oxygen and ions through the coating, make steel corrosion medium and isolation, barrier coating will also slowed the corrosion rate of steel. Electric weld area is the part of the steel members is the most easy to rust. Practice shows that the electric arc spraying zinc (aluminum) welding and hot dip zinc coating of steel components installed, with cold galvanized to repair weld, it is an economic and efficient way. It is also the best sand were used after removing the old paint film, rusty spot, steel surface with certain roughness. If conditions, also can use manual and wind (electric) powered tool polishing cleaning method. High quality cold galvanized steel and conform to the specifications of the surface treatment, also must rely on the good coating construction, the biggest superiority, can give full play to the cold galvanizing steel effective protection. In addition to various specifications, various types of cold galvanizing aerosol cans, which is the most commonly used method: brush, air spraying and high-pressure airless spraying 3 kinds. Roller speed, but because of poor permeability, tend to be trapped air in the film, so not suitable for primer coating. It can be used as a long-term anti-corrosion primer of offshore and onshore steel structure, can be matched with many kinds of anticorrosive coating, used for buildings, Bridges, steel box girder, tower, all kinds of pipe, Marine engineering, mine, gate, tunnel, rail, steel structure such as fence. It is replaced by hot dip galvanized, electric arc spraying zinc (aluminum) the best materials, can be used to heat (spray) update and fix, galvanized layer can also be used for arc spraying zinc and other projects of CLP weld repair. As heavy-duty coating, cold galvanized coating engineering also involves the production and environmental protection and construction personnel and the public's occupational health and safety, and environmental protection is mainly the development direction of cold galvanizing.
