Built for the Next Generation of Galvanizing and Color Coating Lines
The successful start-up of Roofings Rolling Mills’ new cold mill complex in Uganda marks a major step forward for East Africa’s steel industry. Supplied by Danieli, the complex includes a single-stand four-high cold reversing mill, a hot-dip galvanizing line, a color coating line, and a coil-to-coil trimming line.
The first galvanized coil was produced in October 2025, followed by the first color-coated coil in November 2025. The galvanizing line runs at speeds up to 160 m/min and processes strip from 0.15 to 0.8 mm thick and 600 to 1,250 mm wide, while the cold reversing mill reaches 1,100 m/min and handles ultra-thin strip down to 0.15 mm. For such lines to deliver consistent corrosion resistance and surface quality, precise chemical coating and passivation are essential. The ASCON Precision Roll Coater is engineered for exactly these requirements.
Product Overview
The ASCON Precision Roll Coater is a high-precision chemical coating and passivation system for uniform application of protective films and chemical treatments onto metal strip. It is a critical component in continuous galvanizing, color coating, and surface treatment lines, ensuring consistent coating thickness, superior corrosion resistance, and reliable strip surface quality.
Core Function: Passivation and Protective Coating
The primary function is to apply a thin protective film—such as a trivalent chromium-based passivation solution—onto the strip surface to protect against corrosion. By uniformly transferring the painting or passivation solution through coordinated applicator and pick-up rolls, the system significantly improves the oxidation and corrosion resistance of the strip. This is especially important for galvanized coils used in automotive, appliance, and construction applications, where white rust and surface defects cannot be tolerated.
Precision Engineering and System Design
The ASCON Roll Coater incorporates several advanced engineering features:
- Coating Head Configuration: Coating heads are positioned on the front and opposite sides of the strip. The front and back applicator rolls have slight off-strip contact to improve coating application consistency.
- Quick-Open Top Side Head: The top side head uses a synchronized quick-opening mechanism, while the front head is hydraulically actuated for precise positioning control.
- Precision Pressure Control: Pressure sensors provide roll pressure feedback, and linear bearings ensure smooth, accurate frame movement. Four load cells are dedicated to the passivation coating rolls for real-time monitoring and adjustment.
Technical Parameters
| Parameter | Specification |
| Strip Width | 450 ~ 2,200 mm |
| Strip Thickness | 0.15 ~ 3 mm |
| Line Speed | 70 ~ 260 m/min |
| Coating Type | Horizontal, Vertical, Winding |
| Delivery Port | Shanghai |
The vertical type roll coater is generally used in galvanizing lines, while all three types are applicable to color coating lines.
Complete System Composition
Each ASCON Precision Roll Coater is supplied as a complete integrated system comprising: Coating Heads (×2), Integral Frame, Coating Rolls (×4), Moveable Top Side Head, AC Electrical Motor, Worm Gear Box, Hydraulic Pump, Working Tank, Hydraulic Cylinder, and Catch Pans (×2).
Applications of Roll Coater
- Hot-Dip Galvanizing Lines – passivation treatment to prevent white rust and enhance corrosion resistance.
- Color Coating Lines – uniform application of primer and passivation layers before painting.
- Surface Treatment Lines – phosphating, lubrication, and other chemical surface treatments.
- Pickling and Cold Rolling Lines – post-treatment and surface conditioning.
For new complexes like Roofings, where galvanized and color-coated coils must meet automotive and construction-grade standards, precise roll coating directly affects product qualification and long-term line stability. As such projects ramp up, demand also grows for reliable roll systems and spare parts that keep coating quality consistent.
Why Choose ASCON
ASCON supplies metallurgical equipment and spare parts covering tension levelers, roll coaters, side trimmers, scrap choppers, and related systems. Our roll coaters are designed for seamless integration with existing galvanizing and color coating lines, with OEM service available to match specific strip dimensions, coating requirements, and line configurations. With export packaging in wooden cases and delivery through Shanghai Port, ASCON ensures safe ocean transport and timely delivery to steel producers worldwide.
