Spraying, a process in which plastic powder is sprayed directly on the product through equipment, is also called electrostatic powder spraying. Plastic spraying is a widely used sheet metal surface treatment process, which is often used for cold plates and galvanized plates.
Spraying is to send the powder coating in the container to the spray gun mouth through compressed air. High-voltage static electricity will be generated at the front end of the spray gun mouth, and an electrostatic field will be formed.
When the paint powder passes through an electrostatic field, it will discharge them, and each powder will become a charged paint ion. Under the action of electrostatic force, it will be attracted by the product with the opposite polarity after being sprayed out, thereby adsorbing on it. Product surface.
When the coating powder piles more and more, the charge will also accumulate. When it reaches a certain thickness, the charged powder will be repelled by the charged powder covering the product, and the coating powder will no longer continue to accumulate.
Before spraying, the surface of the product must be degreasing and rust removing. Because the spraying process sprays the coating powder directly on the product, the adsorption force at this time is not very strong, and high temperature curing is required.
By putting the product sprayed with paint in a certain temperature oven, under the action of high temperature, the paint powder will melt and level by itself, and then solidify to form a dense and strong spray layer.
The coating quality after using this kind of electrostatic spraying will be better, and the adhesion will be stronger, and there will be no liquid sagging phenomenon.