Comparison of advantages and disadvantages of compression airspraying

Compressed air spraying is a coating method that uses a special Spray Gun to atomize the paint liquid into mist by means of the airflow of compressed air from the Air Compressor, and sprays it on the surface of the object. The surface of the sprayed object can form a thin and uniform paint film. In general, the paint film applied by spraying is smoother and more beautiful than that painted by hand.

The main advantages and disadvantages of spraying construction are as follows:

(1) When using spray coating, if the object has pores, inclinations, curves, sand marks, bumps and other places left after grinding, it can be sprayed evenly to obtain a smooth and flat paint film.

(2) The construction efficiency is high, which is 5~10 times faster than the brushing method. In particular, it is more effective to use spraying for large-area objects.

(3) Some paints do not have high flowability and dry quickly, such as nitro paint (commonly known as "spray paint"), perchlorethylene paint, etc. When painting by brushing, the paint film often leaves brush It will affect the appearance due to scratches, and the construction efficiency is low. If spraying is applied, this kind of phenomenon can be prevented.

(4) The disadvantages of spraying construction are:

① Paint consumption up to 40%;

② One time spraying should not be too thick, so the number of construction passes increases;

③The amount of solvent emitted during construction is large, causing serious environmental pollution and the risk of fire and explosion. Therefore, the safety and labor protection measures are more stringent.

Improvement measures and technical treatment methods for spraying construction include:

(1) Construction by thermal spraying is to heat the paint to 60~70°C to reduce the viscosity of the paint. In this way, the amount of diluent can be reduced, the content of film-forming substances in the paint will be relatively increased, and the number of constructions will be reduced.

(2) Spraying is carried out in a special spraying room, and the scattered paint mist can be recovered by a recovery device, which can not only recover part of the materials, but also prevent fire and explosion during spraying.

(3) The solvents and thinners used for painting in the past were mainly benzene solvents, which have been gradually replaced by benzene-free solvents. Benzene-free solvents or thinners cost slightly more, but are less harmful to humans.