Liquid coloring of plastics: extrusion
With the right dosing system, the use of liquid color in extrusion is not only possible but also highly effective, Edonis Isaku, Paul Reuter GmbH & Co. KG
Liquid color dosing system colorDoS for profile extrusion
At Paul Reuter GmbH & Co. KG, extruded profiles are produced for applications such as roller shutters, garage doors, electrical installations, suitcases, furniture, and more. The seven different liquid colors are continuously metered using the colorDoS dosing system. The system operates with a modular mzr-7245 dosing pump.
The pump is synchronized with the extruder's control system, requiring only the input of color density and the color dosage as a percentage of the granulate quantity. If the manufacturing process is paused or interrupted due to an error, the extruder and the dosing pump automatically stop. The system dynamically adjusts the color dosage to match variations in granulate feed rate, ensuring consistent color dosing even when production speed changes.
The production process runs at 25 kg/h granulate throughput, with a color dosage of 0.6% to 0.85%. Daily color changes are common. The fluid connections between the color container and the pump module are short and equipped with drip-free quick-release couplings, making color container changes clean and effortless.
Liquid color is injected directly into the granulate stream above the screw. The HNPM-engineered dosing nozzle design prevents color contamination in the feed zone, allowing for rapid color changes with minimal production interruptions. This optimizes machine uptime and significantly reduces material waste compared to masterbatch usage.
Decision criteria for the Dosing System colorDoS
- Fast color changes for optimized production flow
- Reduced material waste during color change
- Easy handling with a user-friendly setup
- Higher efficiency through liquid color technology
- A cost-effective alternative to masterbatch
Applied dosing system