Commonly used coating methods of primer in automobile sheet metal spray paint

The quality of coating is the result of the comprehensive effects of the three elements of coating, and the correct selection of coating technology is also an important aspect that affects the quality of coating. The so-called choice of coating process is, in a sense, the choice of coating method. Different coating methods are suitable for coating under different conditions, so it is very important to choose the correct coating method. Until a certain point, the coating methods mainly include dip coating, spraying, brushing, roller coating, electrophoresis, scraping, electrostatic spraying, and rubbing. Among them, electrophoresis, spraying, electrostatic spraying and squeegee coating are widely used in automobile coating. The most commonly used method in automotive repair coating is spraying.

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Commonly used coating methods of primer in automobile sheet metal spray paint

1. Dip coating

Dip coating is a coating method in which the surface-treated coated object is directly immersed in a large amount of liquid coating, and the adhesion between the coating and the surface of the coated object is used to make the coating adhere to the surface of the coated object. This kind of coating method is more common in the early production process, and it is suitable for the coating of parts with small volume and low requirements for coating quality. Dip coating has low requirements on production conditions and does not require operators to have a higher technical level, but the waste of coatings is more serious and has a greater impact on the environment.

2. Spraying

Spraying is a coating method that uses special spraying equipment (mainly spray gun) to atomize the paint and apply it to the surface of the object. This kind of coating method appeared late and it has a wide range of applications. Most parts can be painted by spraying. The spray coating is relatively economical, the coating quality is better, and the quality of the coating film is easy to control, but it requires relatively high technical level of the operator, stricter requirements on the spraying equipment, and more serious impact on the environment.

3. Brush

Brushing is a painting method that uses a brush made of animal hair or plant fiber to brush paint on the surface of an object. This coating method appeared earlier, but it has a wide range of applications. Brushing has lower requirements on coating equipment, higher requirements on the technical level of operators, less waste of paint during the coating process, and less impact on the surrounding environment.

4. Roll coating

Roller coating is a coating method in which a roller made of cotton or chemical fiber is used to uniformly coat the paint on the surface of the object through the rolling of the roller. This kind of coating method is suitable for larger area coating. It has lower requirements on coating equipment, but requires higher technical level of operators and less paint waste.

5. Electrophoresis

Electrophoresis is a method in which the object to be coated is immersed in the paint, the object to be coated and the paint are charged with different polarities, and the principle of charge movement is used for painting. Electrophoretic coating has very high requirements for coating auxiliary equipment, with great technical difficulty and high degree of automation. Electrophoretic coating can well control the thickness of the coating film, and the coating quality is high. It is mostly used for the coating of the primer in the manufacture of new cars. Due to the difference in charge applied to the coating, it can be divided into two types: cathodic electrophoresis and anodic electrophoresis.

6. Scrape

Scrape is a coating method in which the paint is scraped on the surface of the object with a squeegee. Scrape coating has lower requirements for coating equipment, higher technical requirements for operators, and less paint waste. Scratch coating is mostly used for dent filling and contour repair in automotive repair coating.

7. Electrostatic spraying

Electrostatic spraying is a coating method in which a certain voltage of static electricity is applied to the spraying equipment to impart a certain voltage of static electricity to the sprayed paint, and the paint is coated on the surface of the object to be coated by the principle of electrostatic adsorption. Electrostatic spraying has higher requirements for spraying equipment, but lower requirements for the technical level of operators, and less waste of paint, which has less impact on the environment.

8. Rubbing

Rubbing is a coating method in which cloth or other materials are dipped into the paint and then the paint is applied to the surface of the object by rubbing. Rubbing application is less, usually when you want to obtain a special effect. It has lower requirements on coating equipment, but higher requirements on the technical level of operators.