Regarding the pre-treatment of Dalian metal spray painting:

Regarding the pre-treatment of Dalian metal spray painting:

Metal adhesion promoter solves the problem of paint peeling on the surface of metal hardware materials. However, during the pre-treatment and surface treatment process of metal spray painting, it is necessary to strictly follow the specifications, clean the Dalian metal surface treatment, strengthen the control and management of the painting process, ensure good adhesion between the spray painting protective layer and the base metal, and prevent the coating protective layer from producing defects such as pinholes, bubbles, wrinkles, cracks, and peeling.

The most commonly used metal materials for spraying are zinc, aluminum, aluminum zinc alloys, stainless steel, etc. In order to improve the adhesion of their surface coating, the general method is to first polish, remove rust and oxide scales on the metal surface, and remove oil and dirt. Before spraying, the metal surface must be cleaned before pre-treatment. This process is obviously quite complicated and involves a large amount of work. High quality phosphating film is only formed on the surface of workpieces that have completely removed foreign objects such as oil stains, rust, and oxide scales.

Because residual oil stains, rust, oxide scales, etc. on the surface of the workpiece can seriously hinder the growth of the phosphating film. In addition, it will also affect the adhesion, drying performance, decorative performance, and corrosion resistance of the coating. Thoroughly removing these foreign substances is a necessary condition for phosphating. Phosphating refers to the process of treating a metal workpiece with an acidic solution containing dihydrogen phosphate, which undergoes a chemical reaction to form a stable insoluble phosphate film layer on its surface. The resulting film is called a phosphating film. The main purpose of phosphating film is to increase the adhesion of the coating and improve the corrosion resistance of the coating.

Drying treatment of phosphating film can serve two purposes. On the one hand, it prepares for the next painting process to remove moisture from the surface of the phosphating film. On the other hand, it improves the corrosion resistance of the film after coating. To establish a pre-treatment production line for painting, the process design must be completed before proceeding with the design, manufacturing, and installation of non-standard equipment. Therefore, process design is the foundation for establishing a production line, and a correct and reasonable route will have a good impact on production operations and product quality.

The commonly used pipeline protective coatings for metal spray painting in Dalian include modified petroleum asphalt, epoxy coal tar asphalt, coal tar enamel paint, polyethylene jacket, epoxy powder, polyethylene adhesive tape, three-layer PE structure, etc. The common purpose of all coatings is to separate corrosive media, but absolute separation is impossible because organic substances have certain water absorption and breathability, and over time they are prone to aging, which is difficult to avoid.