In the powder coating process, the pretreatment process is a crucial step that determines the quality and durability of the coating
The main process flow of pre-treatment for powder coating:
The pre-treatment for powder coating usually involves steps such as degreasing, rust removal, phosphating (or passivation), cleaning and drying
- Deoiling / Oil Removal
Soak or spray the tank with alkaline or neutral cleaning agent to remove the remaining oil stains on the workpiece surface
- Washing
Clean the remaining substances on the surface to ensure the smooth progress of the subsequent processes
- Dealing with rust removal / sandblasting / shot blasting
For the workpieces with oxide scale or rust, they should be cleaned by sandblasting or shot blasting to obtain a rough and clean surface
- Washing
Rinse again to remove the dust and debris generated during the sandblasting or shot blasting process
- Phosphating / Passivation
A protective film forms on the surface of the workpiece, preventing rust and enhancing the adhesion of the coating
- Washing
Remove the residues of phosphating solution or neutralizing solution to avoid affecting the coating performance
- Drying
The workpiece is placed in the drying oven to evaporate moisture, ensuring it is dry and ready for electrostatic spraying
The Importance of Pre-treatment for Powder Coating：
- Ensure adhesion strength
- Improve the anti-corrosion performance
- Improve the appearance quality
Sum up
The pre-treatment process before powder coating determines the performance and lifespan of the coating. Scientific procedures ensure its durability and aesthetic appeal, and it is applicable in multiple fields
