Container Automatic Coating Production Line

Container Automatic Coating Production Line

The container automatic coating production line is a highly integrated intelligent assembly line combining automatic conveying, precise positioning, robot/gantry spraying, paint leveling, drying, cooling and VOC waste gas treatment. It mainly adopts a gantry spraying + robot spraying combined system to replace manual operation, ensuring stable coating thickness, high production efficiency and excellent anti-corrosion performance for marine containers.

Main Process Flow

1. Conveying & Positioning

Roller conveyor lines transport containers at a constant speed with precise positioning control, ensuring accurate alignment at each spraying station.

2. Pre-treatment & Dust Removal

Preheating to remove moisture; high-pressure air automatic cleaning to eliminate dust, oil and impurities on the steel surface.

3. Primer Automatic Spraying

Automatic spraying of epoxy zinc-rich primer by gantry system, with manual pre-coating for welding seams and corner fittings.

4. Leveling & Drying

Flash-off followed by gradient hot-air drying to ensure full curing of the primer.

5. Intermediate Coat Spraying

Epoxy intermediate coat applied automatically to increase film thickness, seal the primer and improve adhesion.

6. Topcoat Automatic Spraying

Polyurethane topcoat sprayed by robots and gantry systems, including color separation and logo spraying.

7. Final Drying & Cooling

Forced drying and air cooling to room temperature.

8. Inspection, Repair & Delivery

Coating thickness, appearance and adhesion inspection; local repair and final delivery.

Core Equipment

- Gantry Spraying System: Used for large flat surfaces such as side walls and roof panels, with full-coverage and high efficiency.

- Explosion-proof Spraying Robots: 6-axis robots with 7th axis track, used for inner walls, base, doors and complex corners.

- Automatic Paint Supply System: 2-component automatic mixing, pressure and flow closed-loop control, automatic color change and cleaning.

- Drying & Cooling System: Cyclic hot-air drying chamber and strong air cooling chamber.

- Environmental Treatment System: Paint mist collection + VOC treatment (zeolite runner + RTO/CO incineration).

- Intelligent Control System: PLC-based automatic control, recipe management, real-time monitoring and quality traceability.

Technical Features & Advantages

- Stable and uniform coating thickness, small deviation, no missing spraying or sagging.

- High paint utilization rate, greatly reducing paint consumption and labor cost.

- Continuous 24-hour operation, stable production tempo (about 4–6 minutes per 40ft container).

- High safety level with reduced manual work in hazardous coating areas.

- Environmentally friendly design with low VOC emissions, complying with industrial environmental standards.

Typical Coating System

- Primer: Epoxy zinc-rich primer

- Intermediate coat: Epoxy micaceous iron oxide intermediate coat

- Topcoat: Acrylic polyurethane topcoat

- Total dry film thickness: 180–260μm, meeting 10–15 years of marine anti-corrosion requirements.