Views: 129 Author: Site Editor Publish Time: 2018-12-05 Origin: Site
Strictly speaking, painting and coating are all spraying process. Painting process is mainly used to oil and lacquer, while coating process used to powder.
1. Introduction
a. Painting
Fill the liquid oil paint into a high pressure equipment, which can disperse the oil paint into small particles when it is jetted out. The particles will be adsorbed by the painted items, like steel strapping bands.
b. Coating
Coating equipment is more complicated than that of painting, including powder supply bucket, high voltage electrostatic generator, electrostatic powder gun. Also, fill the powder into the bucket, then jet the powder out with the help of high pressure. The powder will be adsorbed by the highly electronic items, like steel pyramid post caps. Generally, the powder is epoxy powder or PVC powder.
2. Features
a. Painting
1) The equipment is simple and the production cost is low. No need large investment and capital return faster.
2) The pre-treatment is simple. Just need to unoil and derust, no further phosphating.
3) The oil paint is rich in colors and categories. You have many choices.
4) But the production cycle is long and contains many processes, resulting in relatively high production cost.
5) The operators should be skilled, know the application scope, property, usage and the cautions very well, as well as knowledge of color modulation.
6) Not eco-friendly. The oil paint contains volatile organic solvent, which is poisonous to body and environment.
7) Flammable and explosive.
b. Coating
1) The coating process is simplified, only containing 3 steps: spraying powder, solidification and cooling. The production cycle is shortened.
Energy and resources are saved and efficiency improved.
2) Eco-friendly. There are no organic solvents, except powder. So there are no pollution problems throughout the producing, transporting, storing and using phases. It does less harm to the health.
3) The use ratio of powder is relatively high, normally over 95%. And the powder left can be recycled and reused.
4) The film is sturdy and durable.
5) The thickness of film is 50-300 micrometer for one finish, while that of painting is only 5-20 micormeter. There are no drops, nor holes, resulting no defects that exists in other spraying processes.
6) The color is fixed in the manufactory, so it is hard to change the color and there are not many colors to choose.
7) Generally, the solidification temperature is over 160℃, so not applicable to heat intolerant products, like plastic rebar chairs, rebar caps and drop wire clamps. And the coated items must be conductive, like metal hardware. If not, the items must be treated to be conductive first.
