What Is The Minimum Thickness Of Plastic Powder For The Spray Coating Process Of Rural Lighting Ready Boards In Africa? What Material Should Be Used For Plastic Powder?
Technical requirements for spray coating process of rural lighting ready boards in Africa
Facing the high temperature, strong sunshine, large temperature difference between day and night, frequent sand and dust, and salt spray and high humidity condensation environment in some areas of rural Africa, the minimum thickness of electrostatic spray coating on lighting Ready Board Box should not be less than 80 μ m, and the effective thickness of finished products should be controlled between 80-110 μ m. Weak positions such as corners and welds of the box should not be lower than the lower limit value, and magnetic thickness gauges should be used for multi-point sampling. It is strictly prohibited to use epoxy powder or epoxy polyester mixed powder for plastic powder. Outdoor weather resistant pure polyester (TGIC system) thermosetting powder coating should be used.
Pure polyester plastic powder has excellent UV resistance, and is not easily powdering, fading, or losing light after long-term exposure to sunlight. It is suitable for long-term outdoor installation conditions in Africa; The coating is wear-resistant and resistant to sand and dust erosion, and has good resistance to moisture, heat, and salt spray, effectively blocking the invasion of water vapor and dust into the substrate and slowing down the corrosion of the box. Epoxy powder has insufficient weather resistance and may age and crack in the short term outdoors. It is not allowed to be used for this type of outdoor ready board.
Before spraying, the box must undergo complete pre-treatment of degreasing, acid washing, and phosphating to ensure coating adhesion. The hundred grid test must reach 4B or above. The curing temperature and time are strictly executed according to the plastic powder parameters to avoid pinholes and brittle cracks in the coating. If the project is located near a coastal salt area, the minimum thickness can be increased to 90 μ m to further strengthen the anti-corrosion barrier, extend the outdoor maintenance free service life, and reduce the cost of replacement and operation in the later stage.
