The parts of the spray gun
The basic structure of the spray gun includes gun body, nozzle set (wind cap, nozzle and gun needle, short for three piece), control parts and other accessories. In order to achieve a perfect powder coating effect, it is inseparable from the core components of the powder coating gun. The nozzle suit of the powder spraying gun is usually produced by computer inspection and monitoring. Some responsible and professional manufacturers will adjust each set of nozzle suits manually, and combine the practical tests. Therefore, when replacing nozzle assembly, the three piece assembly is strictly forbidden to appear casual combination phenomenon, otherwise, it will affect the perfect coating effect.
In order to maximize the function and performance of the powder spraying gun:
1, according to different atomization technology spray gun adjust the best spraying pressure (Table 1);
2. Adjust the paint flow to the maximum. If the volume of the paint is too high, try not to move the needle too early, so as not to wear the needle too early.
3. When the gun is sprayed, the air cap of the spray gun should be perpendicular to the surface of the workpiece to be sprayed.
4. When the spray gun moves, its trajectory should be kept parallel to the spray surface. Depending on the use of different spray guns, the spraying distance is also different (Table 1).
5, when spraying, the whole arm moves through the surface of the workpiece to keep the wrist straight and can not run on the arc line, so as to avoid the uneven color of the coating and the uneven thickness of the coating.
6. Trigger the spray gun trigger at the beginning of each spray stroke and release the trigger before the end of each spray stroke.
7. Depending on the type of coating, the range of overlap is 1/3-1/2.
8. Depending on the type of coating, the speed of the spray gun is selected at 30-50 centimeters per second to get the best film thickness.
Table 1 Comparison of three kinds of spraying gun technology
Type of spray gun
(Cap atomization pressure)
Transfer efficiency (varnished rate)
Intake pressure (bar)
Air consumption (liter / minute)
Spray distance (centimeter)
Traditional spray gun
Mainly air pressure atomization (2.5 bar)
HVLP spray gun
It is mainly airflow atomization (0.7 bar)
RP spray gun
Air flow and air pressure atomization (1.2 bar)