Powder coating line, Custom powder coating solutions
A powder coating line is an automated metal surface coating production line based on the principle of electrostatic adsorption. High-voltage electrostatics cause plastic powder to be uniformly adsorbed onto the workpiece surface, and then baked at high temperature to form a dense protective layer.
Working Principle
Core Principle: Utilizing the mutual adsorption of positive and negative electrostatic charges, resin powder is uniformly coated onto the grounded workpiece surface, and then heat treatment forms a dense coating. The spray gun generates a voltage of up to 100kV, overcoming the difficulty of spraying deep cavities and ensuring uniform powder adsorption under the influence of the electric field. After the powder particles are charged, they adhere to the workpiece under the combined action of electrostatic force and compressed air. Before curing, a second spray can be applied to improve the yield.
Process Flow
The complete production line consists of four main stages, forming a continuous operation process.
Pretreatment: Includes degreasing, rust removal, phosphating, or shot blasting, cleaning the workpiece surface and forming a conversion film to improve coating adhesion.
Electrostatic Spraying: Powder is conveyed to the spray gun through a powder supply device and adsorbed onto the workpiece surface under the influence of the electrostatic field.
High-Temperature Curing: Curing temperature is typically 160℃-220℃, time 10-30 minutes, allowing the powder to melt, level, and undergo a cross-linking curing reaction.
Cooling and Unloading: After leaving the curing oven, the workpiece is naturally or forcibly cooled, allowing the coating to harden and set.
System Composition
Main Components: The production line integrates multiple functional modules, connected throughout by a suspended conveyor system.
Loading/Unloading Area: Includes an inspection process for rapid checks of coating appearance, thickness, adhesion, etc.
Pretreatment System: Typically includes pre-degreasing, washing, surface conditioning, phosphating, and drying steps.
Powder Coating Area: Includes a spray booth, spray guns, powder supply system, and powder recovery system; powder recovery rate typically exceeds 85%-95%.
Curing and Cooling Areas: Heating melts and solidifies the powder, followed by cooling and setting
Key Equipment:
Electrostatic Spray Gun: Manual or automatic, maximum powder output up to 350g/min, overcoming the Faraday cage effect.
Powder Supply Device: Powder is fluidized and transported via compressed air, supporting precise powder output control over long pipelines.
Powder Recovery Equipment: Employs a combination of cyclone dust collectors and filter cartridges; oversprayed powder can be recycled and reused.
Application Areas:
Widely used for metal parts requiring surface protection and decoration, applicable to almost all industrial sectors.
Main Industries: Automotive parts, home appliances, architectural aluminum profiles and curtain walls, outdoor facilities, furniture, agricultural machinery, construction machinery parts, etc.
Typical Workpieces: Aluminum profiles, guardrails, control cabinets, air conditioner housings, fan grilles, satellite antennas, new energy vehicle parts (such as body structural components, battery trays, motor housings).
