To achieve a high-quality powder coating, the workpiece surface must be clean, dry, and free of oil. Common pretreatment methods include:
Solvent cleaning method
Chlorinated hydrocarbon degreasing method
Alkaline cleaning method
Acid cleaning method
Shot peening, etc.
After cleaning, immediately perform phosphating treatment to provide the surface with good flexibility and adhesion.
Powder coating can be applied using manual spray guns or assembly lines with multiple spray guns. Powder is fed from the supply hopper, conveyed by airflow to the spray gun, where it is electrostatically charged. The charged powder particles adhere strongly to the grounded workpiece. Normally, airflow or vibration will not cause the powder to fall off. Before entering the curing oven, inspect the coated workpieces carefully; any defects or misses should be re-sprayed immediately. If repair is not possible, remove the powder with compressed air and reapply to improve yield. The coated workpiece is then sent directly into the oven for melting, leveling, and curing at a specified temperature.
To ensure quality coatings, follow these guidelines during application:
Store powder coatings sealed in a cool, dry place and use strictly according to production batch order.
Thoroughly clean all contaminants on the workpiece surface before spraying and conduct proper pretreatment.
Compressed air must be oil- and water-free; regularly check the oil-water separator.
Ensure good grounding connection between the unclean workpiece and conveyor; fixtures should be cleaned regularly to maintain good grounding.
Select the correct coating powder for the final finish required.
Maintain stable oven performance to properly cure the coatings.
Keep the powder supply, recovery system, and spray guns free from contamination or mixing with other powders to avoid affecting the coating appearance.
Regularly inspect pretreatment and curing oven performance, as well as physical properties of all powders.
Recovered powder must be sieved and mixed with new powder in the prescribed ratio.
Avoid the presence of silicone dust or paint dust near the powder coating area to prevent surface defects.
Long-term direct contact may irritate eyes, skin, and respiratory organs.
Ingestion may harm health.
Powder dust can form explosive clouds ignited by flames or sparks.
Smoking and open flames are strictly prohibited.
Only spray guns and necessary cables should be placed inside the spraying booth; all other electrical equipment must be outside (except dust-proof and explosion-proof equipment).
Ensure ventilation/exhaust systems function properly.
Check grounding of fixtures and all electrical equipment.
Operators must be well grounded and must not wear insulating gloves or shoes.
Do not enter the spraying booth while spraying is in progress; personnel in dusty environments must wear suitable masks and protective clothing.
Keep the spraying area floor clean within 5 meters; avoid sweeping and use a damp mop or vacuum cleaner instead.
Leakage: Shut off the gas supply and clean up using a vacuum cleaner.
Flame Ignition: Cut off the gas and high voltage supply; the fire will extinguish itself.
Fire Alarm: Cut off the power supply and extinguish the fire using a fire extinguisher or water mist (foam extinguishers, 1211 extinguishers, or water mist are all suitable).
Eye Contact: Rinse with clean water or a specialized cleansing solution, then seek medical treatment immediately.
Powder Inhalation: Move the affected person to fresh air and loosen their clothing. If breathing is difficult, send them to the hospital immediately.
Powder Ingestion: Send the affected person to the hospital immediately. Do not induce vomiting.
