Powder Coating Line for Chassis and Cabinets

The powder coating line for chassis and cabinets is a production system specifically designed for the powder coating operation of chassis and cabinets. Its aim is to provide high-quality, durable, and aesthetically pleasing coatings for chassis and cabinets, which are widely applied in industries such as electronics, communication, and power. The following will provide a detailed introduction from aspects such as process flow, equipment composition, and advantages and features.

Process Flow

Pretreatment Stage

• Degreasing: During the processing and transportation of chassis and cabinets, their surfaces will be attached with impurities such as oil stains and dust. By immersing the chassis and cabinets in a tank solution containing a degreaser, the chemical action of the degreaser is utilized to decompose and remove the oil stains on the surface, providing a good foundation for subsequent coating.

• Water Washing: After degreasing, the chassis and cabinets need to be washed with water to remove the residual degreaser and impurities on the surface. Usually, multi-stage water washing is adopted to ensure the cleaning effect.

• Rust Removal (if necessary): For chassis and cabinets made of metal materials, if there is rust on the surface, rust removal treatment is required. Common methods include pickling, shot blasting, etc., to remove the rust on the surface and improve the adhesion of the coating.

• Phosphating Treatment: Phosphating is a process of forming a phosphate conversion film on the surface of the chassis and cabinets. This film can enhance the adhesion between the coating and the metal surface and improve the corrosion resistance of the chassis and cabinets. After phosphating treatment, water washing and passivation treatment are usually carried out to ensure the quality of the phosphating film.

• Drying: After the pretreatment, the chassis and cabinets need to be dried to remove the moisture on the surface and prepare for powder coating. The drying method can be hot air drying or infrared drying.

Powder Coating Stage

• Loading: The pretreated and dried chassis and cabinets are hung on the conveyor line, and are sent into the powder coating room through the conveyor line.

• Electrostatic Spraying: In the powder coating room, the powder coating is evenly sprayed onto the surface of the chassis and cabinets by using electrostatic spraying equipment. The electrostatic spraying equipment charges the powder coating through a high-voltage electrostatic generator, and under the action of the electric field force, the powder coating will be adsorbed onto the surface of the chassis and cabinets. This spraying method can make the powder coating evenly cover all parts of the chassis and cabinets, including corners and gaps.

• Fluidization and Recycling: During the spraying process, the powder coating that has not been adsorbed by the chassis and cabinets will be collected and reused through the recycling system. The recycling system usually uses equipment such as a cyclone separator and a filter cartridge filter to separate the powder coating from the air, and makes the powder coating return to the fluidized state through the fluidization device, so as to be conveyed to the spray gun for spraying again.

Curing Stage

• High-temperature Curing: The chassis and cabinets with the powder coating sprayed are sent into the curing furnace through the conveyor line. Inside the curing furnace, the chassis and cabinets are heated to a certain temperature (usually between 180°C and 220°C) and kept for a certain time (usually between 15 and 30 minutes), so that the powder coating undergoes a cross-linking reaction and cures into a hard coating.

• Cooling: After the cured chassis and cabinets come out of the curing furnace, they need to be cooled to reduce their temperature to room temperature. The cooling method can be natural cooling or forced air cooling.

Unloading and Inspection

• Unloading: The cooled chassis and cabinets are removed from the conveyor line, completing the coating process.

• Inspection: Carry out appearance inspection and performance testing on the coated chassis and cabinets, and check whether the indicators such as the thickness, hardness, adhesion, and corrosion resistance of the coating meet the requirements. Unqualified products need to be reworked.

Equipment Composition

• Conveyor System: It is used to transport the chassis and cabinets to move between each process, usually adopting methods such as a hanging conveyor chain or a roller conveyor. The speed of the conveyor system can be adjusted according to production requirements to ensure the production efficiency of the coating line.

• Pretreatment Equipment: It includes equipment such as a degreasing tank, a water washing tank, a phosphating tank, and a drying furnace, which are used for the pretreatment of the chassis and cabinets. These devices are usually equipped with devices such as heating, stirring, and circulation to ensure the stability of the pretreatment effect.

• Powder Coating Equipment: It mainly includes equipment such as an electrostatic spray gun, a powder supply system, and a powder recycling system. The performance of the electrostatic spray gun directly affects the spraying effect of the powder coating. The powder supply system can ensure the uniform supply of the powder coating, and the powder recycling system can improve the utilization rate of the powder coating and reduce production costs.

• Curing Furnace: It is used for the high-temperature curing of the chassis and cabinets with the powder coating sprayed. The heating method of the curing furnace can be hot air circulation, infrared heating, etc., to ensure that the temperature inside the furnace is uniform and the curing quality of the coating is guaranteed.

• Control System: It is used to control the operation of each device of the coating line, including the speed of the conveyor system, the temperature and time of the pretreatment equipment, the spraying parameters of the powder coating equipment, the temperature and time of the curing furnace, etc. The control system can use devices such as a programmable logic controller (PLC) or an industrial computer to achieve automated control and production management.

Advantages and Features

• High Coating Quality: Powder coating can form a uniform, dense, and hard coating, which has good adhesion, hardness, wear resistance, and corrosion resistance. It can effectively protect the chassis and cabinets from the erosion of the external environment and extend their service life.

• Environmental Protection and Energy Conservation: Powder coating does not use organic solvents, reducing the emission of volatile organic compounds (VOCs) and being environmentally friendly. At the same time, the powder coating can be recycled and reused, improving the utilization rate of the coating and reducing production costs.

• High Production Efficiency: The powder coating line adopts an automated production method, with each process closely connected, resulting in high production efficiency. At the same time, the powder coating has a fast curing speed, greatly shortening the production cycle and improving production efficiency.

• Aesthetic Appearance: The powder coating has a rich variety of colors and gloss levels to choose from, which can meet the appearance requirements of different customers for chassis and cabinets. The coating surface is smooth and flat, without defects such as sagging and bubbles, and the appearance quality is good.

• Strong Adaptability: The powder coating line can adapt to the coating requirements of chassis and cabinets of different sizes, shapes, and materials, and has strong versatility and flexibility.