Core Principles:
1.Electrostatic Charging: The spray gun uses high-voltage electrostatics to negatively charge the powder particles.
2.Adsorption Film Formation: The negatively charged powder is adsorbed by the positively charged (or grounded) workpiece, forming a uniform powder layer.
3.Heat Curing: The workpiece enters the curing oven, where the powder melts, flows, and solidifies, forming a dense coating.
Main Advantages:
1.Environmental Protection: No solvent evaporation, virtually no VOC emissions, powder is recyclable with a utilization rate exceeding 95%.
2.Coating Performance: Strong adhesion, high hardness, and superior wear resistance, corrosion resistance, and weather resistance compared to traditional spray painting.
3.Economy: Reduces raw material waste, simplifies the process, and lowers subsequent maintenance costs.
Applicable Materials and Workpieces:
1.Powder Types: Mainly divided into thermosetting (epoxy resin, polyester, polyurethane) and thermoplastic (polyethylene, polyvinyl chloride).
2.Workpiece Requirements: Must be a conductive material, commonly including metal workpieces such as steel and aluminum alloys.
3.Application Scenarios: Mass-produced workpieces such as appliance casings, automotive parts, furniture hardware, and piping equipment.
Key Precautions:
1.Workpiece Pretreatment: Thorough degreasing, rust removal, and phosphating are essential; otherwise, coating adhesion will be affected, leading to peeling.
2.Electrostatic Parameters: Voltage and current must be adjusted according to powder type and workpiece shape to avoid uneven adsorption.
3.Curing Conditions: Strictly control the temperature and time of the curing oven. Insufficient temperature will cause the coating to soften, while excessive temperature may cause yellowing.
