白面牛卡纸涂布机生产线

A duplex board white top coating machine line is a production system used to coat one or more layers of white coating (topcoat and precoat) on grey-back duplex board. It improves surface smoothness, brightness, printability, and appearance for packaging applications such as boxes, cartons, and printing products.

Typical machine speeds range from 150–350 m/min, depending on coating method (air knife or blade), drying capacity, paper basis weight, and machine width. High-capacity lines can reach up to 450 m/min with advanced drying and tension control systems.

Commonly used coating heads include:
Blade coater (high smoothness, excellent printability)
Air-knife coater (uniform coating weight, good for high coating thickness)
Curtain coater (optional for ultra-smooth topcoat)
Different coating heads may be combined for pre-coat and top-coat layers depending on quality requirements.

Coating weight varies by application, but most mills apply:
Pre-coat: 12–20 gsm
Top-coat: 8–15 gsm
Total coating weight generally falls between 20–35 gsm to achieve high surface gloss and good offset or digital printing performance.

The baseboard should meet:
Grammage: 100–450 gsm
Smooth and stable surface (low roughness)
Moisture: 6–8%
Good stiffness and strength
Higher-quality greyboard ensures uniform coating and minimizes defects such as streaks or pinholes.

A complete line typically includes:
Hydraulic unwinder and auto-splicer
Pre-coat and top-coat stations (blade/air-knife)
Multi-zone hot air drying system
Infrared dryers (optional for fast drying)
Cooling cylinders and moisture regulation
Calender or soft-calender for surface finishing
Rewinder and automatic reel changer
Touchscreen PLC control system

A standard 2.5–3.6 m duplex board line typically requires:
Electrical power: 120–250 kW
Steam system: 0.6–1.0 MPa for drying cylinders
Compressed air: 0.6–0.8 MPa
Hot-air ovens and exhaust system
Energy consumption depends on paper width, drying capacity, and coating thickness.

We would offer:
1. On-site installation and commissioning
2. Training for operators, coating technicians, and maintenance staff
3. Coating formula and process parameter guidance
4. Spare parts supply and quick-response after-sales
5. Remote technical support via video or online diagnostics
These services ensure stable production and fast start-up.