Spray Paint VS Spray Plastic, It Is Also Important To Dress The Product

Spray paint VS spray plastic, it is also important to "dress" the product

Spraying various coatings on the surface of the product is one of the most important processes in surface treatment, which not only makes the product look good, but also protects the product matrix.

Spraying and spraying are two widely used spraying processes. To say what is the difference between them, I believe that many people do not understand, and some even think that this is a different name for the same process, but in fact, spraying Molding and painting are two different processes, and the equipment and process used are also different.

spray paint

Spray painting is by pouring the paint into a container, pressurizing it with a mechanical device, and spraying the paint on the product in the form of a mist to form a paint film. The spray painting process is widely used in ships, locomotives, bridges, machinery and other fields.

The main function of spray painting is to prevent rust, corrosion and decoration of products or semi-finished products.

According to the operation mode, painting can be divided into manual painting and automatic painting. Manual spray painting is a hand-held spray gun that sprays the product according to the shape of the workpiece.

▲ Spray gun structure

The advantages of spray guns are flexible operation, suitable for different environments, shapes and sizes of products, simple equipment and low energy consumption. However, the production efficiency of the hand-held spray gun is low, and the spray quality is also unstable.


Automatic painting is the use of mechanically operated spray guns to spray products. The productivity is higher and the spraying quality is stable, but most of the equipment is not cheap and the structure is more complicated.


Spray painting can also be divided into air spray paint and high pressure airless spray paint. Air spray painting uses a spray gun as a tool, and relies on the airflow of compressed air to blow, atomize and spray the paint on the surface of the product to form a paint film.

▲ High pressure airless sprayer

High-pressure airless spray painting is to use a high-pressure pump in a closed container to pressurize the paint and spray it from the spray gun. Due to the sudden drop in pressure, it expands and atomizes violently, and sprays onto the surface of the workpiece to form a paint film.


In the production process, before painting the product, it is necessary to clean the surface of the product through rust removal, oil removal, cleaning, drying and other processes.

The spray paint is directly sprayed with one layer, or it is repeated 2~3 times to obtain a dense and firm paint layer. However, after the first spray paint, it must be polished before the next spray paint.


▲ Painting process

spray

Compared with spray painting, plastic spraying is more complicated. It is a process of spraying paint powder directly on the product through equipment, also known as electrostatic powder spraying.

Spray plastic is a widely used metal surface treatment technology, which is very popular in the fields of hardware, home improvement and building materials.


Plastic spraying is to send the powder coating in the container to the mouth of the spray gun by means of compressed air. At the front end of the spray gun mouth, high-voltage static electricity will be generated, and an electrostatic field will be formed.

When the paint powder passes through the electrostatic field, it will discharge them, and each powder will become charged paint ions. product surface.
 

▲ The principle of spraying

When the coating powder piles up more and more, the charge will accumulate more and more. When it reaches a certain thickness, the charged powder will be repelled by the charged powder covering the product, and the coating powder will not continue to accumulate.

▲ A complete set of spray equipment

Before spraying, the surface of the product also needs to be cleaned. Because the spraying process directly sprays the coating powder on the product, the adsorption force at this time is not very strong, and high temperature curing is required.


▲ Plastic spraying process

By placing the sprayed product into an oven at a certain temperature, under the action of high temperature, the coating powder will melt and level itself, and finally form a dense and firm spray layer after curing.


▲ Spray oven temperature setting

The quality of the coating after using this electrostatic spray will be better, the adhesion will be stronger, and there will be no liquid sagging.