Batch Blending

Gravimetric batch dosing units are used when pourable granulates, ground stock, masterbatch and/or other additives must be blended precisely before they are fed into the plastic processing system. These devices may be installed and operated either directly on the processing machine (such as an injection-moulding or extrusion system) or next to the machines.

The components are metered, one after another, into a weighing container connected to a weighing system. When weighing is completed, the entire mixture (also called a batch) pours into the so-called blending chamber where it is evenly blended by a blending blade. All granulate-touching components are manufactured from stainless steel as standard.

A filling detector installed at the blending chamber’s exterior monitors the entire blending cycle. Parametrisation and operation of the batch dosing unit is made easy, thanks to the user-friendly hand-held controller. All individual component hoppers can be cleaned and maintained very easily as every hopper can be removed and replaced without extra tools.

Batch blending devices are usually fed by an automatically-operated granulate feed system (suction feeding). When the batch dosing unit is installed directly on the processing machine, the ready blend will immediately pour into the feed opening of the plasticating unit. If the blending unit is installed next to the machine, a granulate-feed system will use suction to move the ready blend from the batch dosing unit into the processing machine.

If required, the control system can be supplemented by a recipe library for various blends and/or process data tracking for back-up and traceability of the processing data.