We all know that alloy wheels are an important part of automobiles. The spraying process of alloy wheels not only has an important influence on the appearance of alloy wheels, but also plays an effective role in preventing corrosion. With the development of the automobile industry, aluminum alloy wheels have become popular with major automobile manufacturers and consumers because of their lightweight, beautiful and fashionable appearance.

In order to improve the quality of aluminum alloy wheels, it is necessary to increase the technical content of the exterior paint film to effectively protect the internal structure of the aluminum alloy and make the appearance of the alloy wheels more beautiful. The primer-free process can not only effectively ensure the flat surface of the ground material, but also improve the spraying process and improve the overall performance of the alloy wheel. Therefore, today we will introduce the application of the primer-free process in the spraying of automobile alloy wheels.

1. Introduction to the primer-free process of the automobile alloy wheel coating production line

At present, the coating process of automobile alloy wheels includes pretreatment, primer, drying, grinding, primer, color paint, drying, transparent powder, and drying. The function of the spray primer is to improve the flatness and resistance of the substrate surface. In the coating process of automobile alloy wheels, the primer-free process can greatly improve the shortcomings of the coating process, optimize the process flow, save materials and costs, and effectively protect the environment.

2, the problems in the primer-free process of the automotive alloy wheel coating production line

Although the primer-free process is more advanced, there are still certain problems. Due to the poor covering effect of colored paint, it is not easy to control the amount of paint spray when the thickness of colored paint is controlled. Once the amount of paint is insufficient, problems such as sandpaper printing and colored paint sagging will occur. Different types of paint, aluminum powder and film thickness are not easy to control.

In the spraying process, the color paint and solvent of the primer-free paint are easily volatilized, resulting in quality problems in the paint film. If the hiding power of the colored paint is limited, and the above-mentioned quality defects must be avoided in the process, it is necessary to effectively control the spray angle and parameters. In the primer-free process, it is also very difficult to control the thickness and color uniformity of the paint film. The primer-free process requires high consistency of spraying. In order to achieve uniform control of the thickness and color of the paint film, it is necessary to strengthen the control.

However, due to the insufficient hiding power of the silver particles of the paint, the color will change with the thickness of the paint film, and even subject to the limitations of the shape of the alloy wheel, the thickness of the paint film will inevitably vary greatly during spraying. For example, the color is obvious.

3. Improvement of the primer-free process for the coating production line of automobile alloy wheels

1. Adopt advanced materials and stable processing system

In the primer-free process, the grinding process should be minimized and the pretreatment process of the alloy wheel hub blanks should be continuously improved. Advanced degreasing materials and advanced treatment systems can be used to effectively ensure that the surface of the alloy wheel is clean and create a uniform, detailed and tight passivation film.

2. Improvement of powder spraying and painting process

In order to improve the quality of powder spraying, it is necessary to strengthen the control of the cleanliness of the powder room, clarify the parameters of the powder spraying process, reduce the number of powder bags and powder pits, and optimize the polishing process. In order to improve the stone-strike resistance of alloy wheels, it is necessary to improve the painting process and improve the coating performance.

In the manufacture of automobile alloy wheels, it is necessary to strengthen the application of the primer-free process. Although this process is not much different from the traditional spray primer process, the advantages of this process cannot be ignored. The alloy wheels using the primer-free process can not only effectively reduce manufacturing costs, but also improve production efficiency and optimize process flow. In addition, after applying the primer-free process, the standard of the spray booth can be further reduced, which can effectively shorten the conveyor chain and save a lot of money. In addition, after applying the primer-free process, it can also achieve the effect of energy saving and emission reduction, reduce the emission of harmful volatiles such as VOC, and effectively improve the environment.