We usually use all kinds of trash cans, and plastic garbage bin is a very common manufacturing process. Corresponding to the traditional spray paint trash can, plastic garbage bin has very excellent characteristics.
Today, we will introduce the the principle of plastic spraying in the production of garbage cans.
The powder coating is sprayed on the surface of the workpiece with electrostatic powder spraying equipment, called electrostatic plastic spraying machine. Under the action of static electricity, the powder will be evenly adsorbed on the surface of the workpiece to form a powder coating.
After high temperature baking, leveling and curing, the powder coating becomes the final coating with different effects of powder coating. The spraying effect is superior to the spraying process in mechanical strength, adhesion, corrosion resistance and aging resistance.
1. Pretreatment
The purpose is to remove the oil, dust and rust on the workpiece surface, and generate a phosphating layer which is corrosion-resistant and can increase the adhesion of the sprayed coating on the workpiece surface.
Main process steps: oil removal, rust removal, phosphating and passivation.
After pretreatment, not only the surface of the workpiece is free of oil, rust and dust, but also a uniform and rough gray phosphating film which is not easy to rust is generated on the original silver white shiny surface, which can not only prevent rust, but also increase the adhesion of the plastic spraying layer of the plastic garbage bin.
2. Electrostatic spraying
The purpose is to evenly spray powder coating on the surface of workpieces. Special workpieces including positions prone to electrostatic shielding should be sprayed by high-performance electrostatic spraying machine.
Process steps: using the principle of electrostatic adsorption, spray a layer of powder coating evenly on the surface of the workpiece. The falling powder is recovered through the recovery system and can be reused after screening.
3. High temperature curing
The purpose is to heat the powder coating on the surface of plastic garbage bin to the specified temperature and keep it warm for corresponding time to melt, level and cure it, so as to obtain the desired surface effect of the workpiece.
Process steps: push the sprayed workpiece into the curing furnace, heat it to the predetermined temperature, generally 185 degrees, and keep it warm for corresponding time about 15 minutes; Open the furnace, take out and cool to get the finished product.
4. Decoration treatment
The purpose is to make the workpiece after electrostatic spraying achieve a special appearance effect, such as various wood grain, pattern, brightening and so on.
Process steps: shading; Transfer printing and other treatment processes.
1. Compared with the traditional painting process, the electrostatic spraying process has significant advantages. No thinner is required, and the construction has no pollution to the environment and no toxicity to human body.
2. It has excellent coating appearance quality, strong adhesion and mechanical strength.
3. The curing time of spraying construction of plastic garbage bin provided by many trash bin manufacturers is short.
4. The corrosion and wear resistance of the coating is much higher without primer.