Sometimes we may meet with the below issues during the powder coating.
The powder can be sprayed out of the powder coating gun normally but no powder or little powder is adsorbed to the metal surface, this is one of the common problems in the electrostatic spraying process for many spray guns, which not only wastes powder but also affects the powder coating efficiency.
Why?
The reasons are mainly as follows:
1. The powder injection sleeve (Venturi tube) in the powder pump is worn out;
2. The voltage or current of the spray gun is set too low;
3. The parameter for the atomizing air is set too high;
4. Water goes into the powder coating gun, the high-voltage static electricity is short-circuited, so the system is in a protection state, and the output voltage is very low;
5. The powder used is not for electrostatic powder coating, the powder is damp, or the powder is of inferior quality;
6. The gun control unit, the workpiece, and the earth are not well connected (poor grounding)
7. Gun failure, gun control unit failure, or disconnection of the cable between the spray gun and the gun control unit.
How to solve it?
For each of the above, we have the following solutions:
1. Check and replace the powder injection sleeve (Venturi tube);
2. Set the gun voltage and current according to the instructions;
3. Reduce or close the atomizing air;
4. Disassemble and fully dry the spray gun, check and solve the source of moisture, and ensure that the compressed air is dry;
5. Replace with qualified electrostatic powder;
6. Check the connection of the grounding;
7. Overhaul the spray gun, the gun control unit, and the gun cable;
