Automatic Painting Line for Aluminum Coils and Stainless Steel Coils

The Automatic Painting Line for Aluminum Coils and Stainless Steel Coils is a fully automated industrial equipment designed specifically for the surface coating processing of metal coils. It can efficiently complete the entire process of surface degreasing, phosphating, painting, and curing for aluminum coils and stainless steel coils. Widely used in fields such as building materials, home appliances, auto parts, and decorative materials, it provides metal coils with high-quality coatings that are uniform, wear-resistant, and corrosion-resistant, meeting the dual needs of different industries for the aesthetics and functionality of metal surfaces.

I. Core Advantages

1. High Efficiency & Automation, Cost Reduction & Efficiency Improvement

The equipment adopts a full-process PLC control system, realizing unmanned continuous operation of feeding, pre-treatment, painting, drying, and winding, which significantly reduces manual intervention. Compared with traditional manual painting, the production line speed can reach 10-30 meters per minute (adjustable according to coil thickness and coating requirements), and it can process thousands of square meters of metal coils per day. At the same time, it avoids problems such as uneven coating and missing spray caused by manual operation, reducing rework rate and labor costs.

2. Stable Coating Quality, Adaptable to Multiple Needs

Equipped with a high-precision atomizing paint gun and an automatic thickness detection system, it can accurately control the coating thickness (usually 5-50μm), ensuring that the coating uniformity error on the surface of each square meter of coil is ≤3%. It supports various coating types such as solvent-based, water-based, and powder coatings, and can customize different surface effects such as matte, bright, and colored according to customer needs, meeting the appearance and performance requirements of diverse scenarios such as building material decoration and home appliance casings.

3. Environmental Protection & Energy Saving, Compliance with Industry Standards

The production line integrates a multi-stage waste gas treatment system (activated carbon adsorption + catalytic combustion), with a waste gas emission concentration ≤30mg/m³, which is far lower than the requirements of the national Comprehensive Emission Standard of Atmospheric Pollutants. The drying process adopts a waste heat recovery device, which increases heat energy utilization by more than 40%, effectively reducing natural gas or electricity consumption. At the same time, the pre-treatment wastewater can be recycled after sedimentation, filtration, and neutralization treatment, reducing water resource waste by 60% and helping enterprises achieve green production.

4. Intelligent Monitoring, Convenient Operation & Maintenance

The equipment is equipped with an industrial touch screen and a remote monitoring system, which can display key parameters such as production line speed, coating consumption, temperature, and pressure in real time. In case of abnormal conditions (such as insufficient coating, abnormal temperature), it will automatically alarm and shut down, reducing the risk of equipment failure. Core components (such as paint guns, conveyor rollers, and heating tubes) adopt a modular design, reducing the replacement and maintenance time to within 2 hours and minimizing the loss caused by production line shutdown.

II. Working Process

1. Coil Feeding

Aluminum coils or stainless steel coils (with a maximum diameter of 2000mm and a maximum weight of 5 tons) are smoothly transported to the uncoiler through a hydraulic feeding rack. The uncoiler automatically corrects the position of the coils to avoid deviation.

2. Pre-treatment

The coils pass through the degreasing tank (to remove surface oil stains), phosphating tank (to form an anti-rust phosphating film), water washing tank (to clean residual chemicals), and drying room (to dry moisture at 80-120℃) in sequence, ensuring surface cleanliness and adhesion, and laying a foundation for subsequent painting.

3. Automatic Painting

The pre-treated coils enter a closed painting room. Multiple sets of automatic paint guns spray coatings evenly according to preset parameters (coating thickness, spraying speed). The painting room adopts a negative pressure design to prevent paint mist from overflowing; some high-end models are equipped with an electrostatic spraying device, which increases the coating utilization rate to more than 95%.

4. Coating Curing

The painted coils enter the curing oven and complete curing at a temperature of 180-220℃ (adjustable according to coating type) through hot air circulation or infrared heating to form a stable protective film. A cooling section is set at the outlet of the curing oven to cool the coils to room temperature, avoiding coating damage during subsequent winding.

5. Winding & Finished Product

After cooling, the tightness of the coils is adjusted by the tension control system, and the coiler automatically winds the coils into rolls. Finally, the automatic cutter cuts the coils to form finished coils that meet customer specifications (length and diameter can be customized), with no manual intervention throughout the process.

III. Application Scenarios

1. Building Materials Field

It is used for the surface coating of products such as aluminum ceiling panels, stainless steel decorative panels, and color-coated aluminum coils, providing weather-resistant and UV-resistant coatings, suitable for scenarios such as outdoor curtain walls and indoor ceilings.

2. Home Appliance Field

It provides anti-corrosion and easy-to-clean coatings for the metal casing coils of home appliances such as refrigerators, washing machines, and air conditioners, meeting the requirements of home appliance products for appearance texture and durability.

3. Auto Parts Field

It performs high-temperature resistant and anti-corrosion coating treatment on aluminum coils and stainless steel coils for automobiles (such as car body trim strips and exhaust pipe protective covers), improving the service life of auto parts.

4. General Hardware Field

It is used for the surface painting of coils for metal kitchenware, hardware accessories, etc., achieving the dual effects of aesthetics and rust prevention, and expanding the application range of products.