MC-Balance User Manual 4.0.UK.00

4. Metering principleThe Dosing Cylinder® of Movacolor combined with a very precise adjustable stepper motorensures that the additive output is accurate and regular. The neckpiece (a mixing chamber) isdesigned to blend the main material and the additive homogeneously. Movacolor has on stock alarge range of machine neckpieces that usually make a prefect fit to the injection molding machineor extruder. The most common mounting of the neckpiece is between the production machine andthe hopper. In the figure below a cut through of the NST40 neckpiece can be seen.Standard neckpieceDuring operation, the virgin material runs fromthe machine hopper through the neckpieceinto the machine. Inside the neckpiece theVirgin material flow is divided into twostreamsby the cover plate. In the space below thecover plate, the rotating cylinder is dosingadditive.1243Additive is added directly into the center ofthe virgin material flow, just before it entersthe production machine. This is a greatadvantage over metering devices that usebatch pre-mixing because pre-mixing canactually cause material separation.Separation of materials results in an irregularadditive flow into the production machine.56Fig. 31. Color 2. Virgin material 3. Neckpiece 4. Dosing cylinder4. Cover plate 5. Mixing zone 6. To production machine5MC-Balance manual