【 Building materials network 】1. paint Viscosity adjustment
　　
Ordinary air spraying coating The viscosity should be controlled within 18-24s. When the spraying surface is large, the viscosity is low; When the spraying surface is small, the viscosity is high.
　　
The coating viscosity of high-pressure air spraying should be controlled above 30s. In order to control the film thickness, the viscosity can be higher when the spraying surface is large; When the spraying surface is small, not only the viscosity is higher, but also the gun distance is longer, and the paint output is reduced.
　　
During electrostatic spraying, the paint viscosity should be controlled within 15~20s, and the specific viscosity value should be adjusted according to the coating leveling on site.
　　
2. Distance of spray gun
　　
Whether it is an ordinary air spray gun or an electrostatic spray gun, the distance from the muzzle to the workpiece surface should be controlled at about 30cm. The spray gun is too close, the paint atomization is poor, and sagging is easy to occur; If the spray gun is too far away, a considerable part of the paint cannot be sprayed on the surface of the workpiece, resulting in low painting efficiency and a lot of waste.
　　
3. Painting sequence
　　
If there are many irregular surfaces of the workpiece to be sprayed, the hidden surface can be sprayed first, and then the overall spraying can be carried out to avoid repeated spraying of metal powder Enamel This will cause local sagging (metal powder paint is more prone to sagging than ordinary paint), affecting the appearance quality.
　　
4. Spray gun
　　
The spray gun shall be adjusted to the appropriate air pressure, flow and spray angle as far as possible according to the use demand to ensure that the paint film thickness is required without sagging. The atomized coating shall be sprayed to the surface of the workpiece in a large sector as possible to improve the spraying efficiency and quality.