Electrostatic Coating Line

Electrostaitc coating is advanced technology which is operated under high voltage environment. Coating is seamless painted on product surface with higher thickness. It’s primary choice for high quality powder coating solution.

Tech view: Powder coating is formed in fog with electric conductivity during painting. Under this environment, coatings are moving on product surface and result in a smooth film.

Advantages of electrostatic coating

• be able to get thicker film by one time spray, normally 4~6 times more than regular solvent coating.
• environment friendly, no solvent or waste gas pollution.
• high efficient output rate and waste powder recycling
• low cost for coating and equipment investment

Electrostatic coating technology is widely used in various industry like automotive and furniture etc.

Electrostatic coating line workflow: loading -> dust removal -> electrostatic coating spray -> curing -> cooling -> unloading

Quality control: During coating workflow, pretreatment is crucial part to ensure high quality result. Moreover, the duration, spray gun, voltage and powder quantity control are all essential factors.

Coating line main components

This includes spray booth, static generator, spray gun and powder supply system.

Spray booth – main part of coating line. stable air supply and cleanness is crucial. clean level must be 10000+. Moreover, spray booth should be configured for easy cleaning so no waste powder can be stored inside.

Electrostatic spray gun – there’re multiple types guns depends the coating line setup. electric system of spray gun is important for efficiency. Generally, automatic spray gun provides better stability and quality.

Powder supply system – this includes powder tank, air compressor, oil/water filter, valve, air pipe and powder pipes etc. Following is the most common choice

For any part selection, you have to evaluation your product properties and production requirements. Incorrect choice will lead to high rate bad products and cause problems to coating line. A decent engineer be able to contribute a list of compatible components to support a high quality coating line production.

Electrostatic Coating Line Process

Cleaning and Dust Removal
During production, transportation, and storage, the surface of plastic parts can accumulate dust, oil, release agents, and other impurities. Common methods for cleaning and dust removal include manual wiping with a clean soft cloth dipped in an appropriate amount of cleaning agent to gently wipe the surface of the parts, removing dust and oil.

Ultrasonic cleaning can also be used, where the parts are placed in an ultrasonic cleaning tank with a cleaning solution. The ultrasonic vibrations help dislodge dirt from the surface, providing a more thorough cleaning, especially suitable for parts with complex shapes and small crevices.

Electrostatic Dust Removal
After cleaning and roughening, some tiny dust particles may still remain on the plastic surface. Electrostatic dust removal uses the principle of electrostatic attraction. The parts are placed in an electrostatic dust removal device, where dust particles acquire a charge and are attracted to the collection device, ensuring a clean, dust-free surface and providing a good foundation for subsequent electrostatic spraying.

Electrostatic Spraying
Load the prepared paint into the paint drum and adjust parameters such as spray pressure, distance between the gun and the parts, and the movement speed of the gun. These parameters affect the coating thickness, uniformity, and appearance quality.

Turn on the electrostatic generator to create an electric field between the gun and the parts. As the paint is sprayed, the paint particles acquire a charge and are attracted to the part surface by the electric field force, forming a uniform coating. The advantages of electrostatic spraying include high paint utilization, reduced paint waste, and uniform, strongly adhered coatings.

Drying and Curing
Control the temperature and time of the drying oven according to the paint’s curing requirements. Excessively high temperature or prolonged time may cause discoloration or cracking; too low temperature or insufficient time may result in incomplete curing, affecting coating performance. For example, the curing temperature for acrylic paint is generally between 60 – 80°C, with a curing time of approximately 30 – 60 minutes.

Electrostatic coating line FAQ

What exactly electrostatic coating line is?

It’s available for electrostatic powder coating as well as electrostatic liquid painting. The application principle is explained in above sections.

What kind of product is suitable for electrostatic coating?

For powder coating, it’s mostly for metal objects while electrostatic liquid painting is compatible for both plastic and metal products.

What do I need to provide for coating line design?

We need to know about your out put rate, product dimensions and workshop structures to start design. Because it’s a custom setup project, it’s the best to discuss across the table.

What kind of service do I get?

Our engineer will provide CAD design based your exact requirement, then we’ll start producing in factory. We also provide onsite installation and training service to make sure you receive the right products.

What spare parts do I need to aware?

The spare parts include filters, lamps and heating pipes.