Aluminum fluorocarbon spraying equipment and process

【China Aluminum Industry Network】 Aluminum fluorocarbon coating itself determines the performance, spraying equipment must ensure that the excellent atomization, to ensure the uniformity of the spray coating, the distribution of metal particles in the fluorocarbon coating, directly affect the appearance of the coating effect . The coating is uniform, and the quality of the fluorocarbon coating has a metallic luster, vivid colors and a distinct three-dimensional appearance. The use of fluorocarbon spray coating on unsuitable spray equipment can result in uneven color, shading on the surface or poor coating. Greatly affected the decorative effect of fluorocarbon, in order to achieve a good spray effect, all use high-voltage electrostatic electric spray gun. The United States, Japan, Germany and other countries produce various types of various types of spray guns. Each has its own characteristics. The fluorocarbon spraying process uses multi-layer spraying to fully utilize the advantages of durability and weather resistance of Kynar 500 metallic paint. From the front surface treatment of aluminum materials to the spraying process, strict quality control is required, and the final product must reach the United States architectural manufacturing. Industry Association AAMA-605.02.90 standard. Aluminum fluorocarbon spraying process flow is: Pre-treatment process: degreasing of aluminum material → washing → caustic washing (degreasing) → washing → pickling → washing → chromating → washing → pure water washing Spraying process: spray primer → topcoat → varnish → baking (180-250°C) → quality inspection The multi-layer spraying process uses three sprays (three sprays for short), spray primer, topcoat and varnish, and secondary spray (primer, topcoat). 1 The purpose of the pre-treatment: Before the aluminum alloy profiles and plates are sprayed, the surface of the workpiece shall be subjected to oil removal and chemical treatment to produce a chromium film, which will increase the binding force and oxidation resistance of the coating and the metal surface, which is conducive to prolonged The service life of the film. 2 Primer coating: As a primer coating for a closed substrate, its role is to improve the coating's resistance to penetration, enhance the protection of the substrate, stabilize the surface layer of the metal, and enhance the adhesion of the topcoat to the metal surface. The color uniformity of the topcoat coating is typically 5-10 microns. 3 finish coating: The top coat is the key layer of the spray coating. It is to provide the decorative color needed for the aluminum, so that the appearance of the aluminum material meets the design requirements, and the metal surface is protected from the external atmosphere, acid rain, and pollution. Erosion to prevent UV penetration. The anti-aging ability is greatly enhanced. The topcoat is a thicker layer of paint in the spray coating. The thickness of the paint layer is generally 23-30 microns. 4 varnish coating: varnish coating also known as varnish coating, the main purpose is to more effectively enhance the anti-corrosion ability of the paint layer, to protect the topcoat coating, increase the color of the top metal gloss, the appearance of a more vivid color , dazzling, coating thickness is generally 5-10 microns. The total thickness of the three spray layers is generally 40-60 micrometers, which can be thickened for special applications. 5 Curing treatment: The three sprayed layers generally require secondary curing, and the aluminum material enters the curing furnace. The curing temperature is generally between 180°C and 250°C, and the curing time is 15 to 25 minutes. Different fluorocarbon coating manufacturers will use their own The paint provides better temperature and time. The chlorocarbon spraying plant (the oyster plant) also has changed its two-shot curing to three-shot curing according to its own experience. 6 Quality inspection: Quality inspection should be in accordance with AAMA-605.02.90 standard. Strict quality checks ensure high quality spray products.