Enamel Factory Wet Electrostatic Coating Process

Since the 1960s, people have imagined using the principle of static electricity to wet enamel with enamel slurry. In the field of organic chemistry, when the particles leave the spray gun, if the object to be coated is grounded, the charged particles will be deposited on the object. Organic coatings usually have higher electrical resistance, so better deposition efficiency can be achieved. And enamel slurry, especially the water-containing system with high conductivity, even if the voltage reaches about 80kV, its deposition efficiency is quite low. To improve the spraying efficiency of paint, it is necessary to strictly control various variables that affect deposition, such as the humidity and temperature of the spray booth, and establish a good overspray recovery system.
The overall electrostatic wet spraying system includes spray gun, trigger control system, supply barrel, static electricity generating device, piping system, elevator, spray booth and recovery system. An insulating grid can also be hung behind the workpiece to be sprayed to prevent overspray.

Electrostatic spraying must first produce a soft atomized spray, so the atomization design of the spray gun is very important. The development of the electrostatic spray gun has achieved atomization at a lower pressure this year. Secondly, the enamel glaze needs to be fully charged with static electricity to be more efficiently adsorbed on the workpiece. The static electricity generating device must provide a sufficiently high voltage and the most suitable charging method must be used to make the enamel glaze truly charged with static electricity. Since the enamel glaze is water-based, it is easy to cause harm to people after being charged, so the electrostatic spraying system needs to be equipped with a safety interlock control device. Electrostatic wet spraying due to the very fine atomization and rapid water loss during spraying, and the humidity needs to be supplemented in time. Therefore, it is best to be equipped with a humidity control system in the overall design.

In order to facilitate the electrostatic charging of the enamel glaze, the particle size of the enamel slurry is usually required to be finer. When the workpiece is more complicated, it is necessary to add a manual spraying station before the electrostatic automatic spraying.

Compared with traditional automatic spraying, the edge wrapping effect of electrostatic wet spraying products is better, and the uniformity of the coating is greatly improved. The flatness of the coating can be comparable to that of electrostatic dry spraying. At the same time, due to its The enamel glaze used is a traditional enamel slurry, so the variety and adaptability of the enamel glaze are much better than electrostatic dry powder, especially for products that require multiple colors, which has great advantages. The most representative product is architectural decorative enamel panels, which do not require a better appearance and require rich colors. Therefore, electrostatic wet spraying can more effectively meet its production efficiency and quality requirements. In addition, products such as oven panels, cabinets, stove panels, and washing machine housings can also use this coating method. In recent years, it has also begun to be used in the production of heat exchange enamel components in the thermoelectric industry.