Custom-engineered uptime on a 10-color CI flexo press

Project summary: NOVA XLS chamber system and custom EPQ ink supply on Allstein CI flexo press

A German flexible packaging converter upgraded its 10-color Allstein Hydro CI flexo press to run high-quality film printing using both water-based and solvent-based inks.

AkeBoose replaced the press’s original composite chambers with ten robust NOVA XLS stainless steel systems to ensure mechanical stability. To prevent water-based inks from drying in the end seal area on low-absorbing film, integrated ESS end seal humidification systems were implemented.

The upgraded ink loop features a custom-engineered EPQ pump solution with integrated automatic cleaning and built-in viscosity control, allowing operators to switch reliably between water-based and solvent-based inks. While the automatic wash-up system handles the fluid lines, extra standby chambers are utilized to prepare upcoming jobs offline with fresh blades and seals to slash changeover times.

The challenge: Eliminating unstable composite chambers and dried-on ink

Printing high-quality designs on low-absorbing plastic film is a demanding process. A German flexible packaging producer experienced this while running a 10-color Allstein Hydro CI flexo press with a print width of 1,400 mm. The challenge was amplified by the need to run both water-based and solvent-based inks on the same press.

The original composite chambers supplied with the press lacked the mechanical stability required for consistent, high-speed production. Furthermore, the customer experienced leaks, premature seal wear, and print defects related to the non-absorbing film substrate requiring a quick-drying ink formula, which also dried up inside the chamber and around the end seals. Lastly, changing colors and switching between water-based and solvent inks required intense manual cleaning. This caused extensive press downtime.

The engineering: Rigid stainless steel chambers and a specialized dual-ink pump system

AkeBoose engineered a complete, heavy-duty retrofit of both the doctor blade chambers and the ink supply loop. The solution was tailored to the press's physical movement and strict safety requirements.

1. The original composite units were replaced by ten NOVA XLS stainless steel chambers. The rigid stainless steel body provides exceptional mechanical stability. It prevents chamber flexing and ensures stable contact with the anilox roller over the entire length.
2. To master water-based ink on film, AkeBoose integrated the End Seal Spray System, or ESS. The ESS continuously moistens the critical end seal zone during production. This action prevents ink from drying out at the edges, eliminating leakage and keeping the press running cleanly.
3. AkeBoose developed a customized EPQ pump system with integrated viscosity control. This system’s outstanding feature is its ability to handle both water-based and solvent-based inks. The supply system features an automated washing process that thoroughly flushes the pumps and hoses. This makes the transition between the two ink types safe, reliable, and highly efficient.

All components in the ink loop were designed and built in line with explosion-protection requirements to ensure safety for solvent operation. Additionally, the Allstein press opens with a pivoting motion. Therefore, AkeBoose designed a custom pivoting suspension that allows the chambers to swing safely with the press.

The result: Rapid switchovers, automated washing, and zero leakage

This integrated upgrade has transformed the press into a highly productive, flexible operation.

The automatic cleaning process of the EPQ pumps ensures the fluid lines are flushed quickly and reliably when switching inks. To save even more time during job changeovers, the customer utilizes standby chambers. While the press is running, operators prepare these spare chambers offline with new doctor blades and seals. When the next job starts, they simply swap the chambers. This action bypasses on-press adjustments and puts the press back into production immediately.

The combination of ultra-stable stainless steel chambers, the leak-preventing ESS, automatic viscosity control, and offline job preparation has significantly increased the plant's capacity. The system performs to the customer's full satisfaction. AkeBoose’s on-site installation team also received praise for their precise and professional execution.