Liquid color neatly dosed
Changing containers of liquid paint without blue fingertips and stains on the German exercise book – we all know this challenge from our school days. And if there was a fountain pen with red or green ink for a change, you could also observe the color carry over very well.
Even though school is long behind us, a quick and clean color change remains a major challenge for users of liquid colors. In addition to the personal skills of the technician, it is above all the suitable technical solution that contributes to success in plastic injection moulding.
The compact dosing system colorDoS was specially developed by HNP Mikrosysteme for this task. The system is installed on the injection molding machine (SGM) above the screw conveyor and doses the liquid color directly into the flow of granules. colorDoS contains, among other things, a micro annular gear pump, a dosing nozzle, and intuitive display control. The integrated pump ensures exact dosing and high color fidelity with minimal color addition. A modular micro annular gear pump mzr-7245 is used. Depending on the dosing time and the viscosity of the paint, the pump achieves a dosing volume of 0.02 to 100 g of paint per shot.
The display control communicates directly with the injection molding machine and includes various operator levels, a display for the remaining time until the container can be changed, an alarm manager, and a cleaning mode. The employee stores up to 30 color code recipes for the repeated use of the liquid colors in the color code administration. The alarm manager displays warnings, such as a low level of liquid color, which is monitored by a load cell integrated into the can holder. In the event of a fault, the injection molding machine is stopped to avoid rejects.
Short fluid connections between the container and the pump module are provided with non-drip quick-release couplings. The special dosing nozzle design prevents the paint from being carried over in the feed area. The quick and clean color change saves material and time, avoids waste, protects the environment, and ensures optimal utilization of the machines. colorDoS is the appropriate technical solution for switching from masterbatch to the use of liquid colors in plastic injection molding.
