A gravimetic blender is an item of industrial equipment used in the plastics industry to accurately weigh two or more components and then mix them together prior to processing in an injection molding machine, plastics extrusion, or blow moulding machine.

There are two types of gravimetric blender.

Loss in weight

This type of gravimetric blender measures the "loss in weight" from two or more hoppers using a load cell under each hopper. Material is usually dispensed from the hoppers using a screw conveyor. All materials are dispensed together and the rate of dosing from each hopper is controlled to ensure the correct blend is achieved.

Gain in weight (sometimes called a batch blender)

A gain in weight gravimetric blender has two or more hoppers arranged above a weigh-pan. These hoppers contain the components which are to be mixed, at the base of each hopper there is a valve to control the dispensing of material from the component hopper into the weigh-pan. The components are dispensed one at a time into the weigh pan until the target or batch weight is reached. Once the batch has been weighed out the contents of the weigh-pan are dispensed into a mixing chamber where they are blended. The resulting mixture exits the base of the mixing chamber into the processing machine.

A typical application of a gravimetric blender would be mixing virgin plastic granules, recycled plastic, and masterbatch (an additive used to colour plastics) together.

Features
1.Modular detachable structure design, saving space and convenient cleaning;
2.Adopt universal PLC controller to ensure reliable performance and easy maintenance;
3.Adopt advanced control algorithms, automatic optimization, automatic adjustment of compensation and vibration prevention functions to ensure the highest accuracy.
4.Standard models can handle up to four components (more than six components can be customized);
5.Color graphic display, touch screen operation, multiple languages avaliable.
6.With recipe storage function, it can store more than 100 sets of recipes;
7.Hierarchical security password control and alarm history record function;
8.The controller is equipped with a USB2.0 interface as standard, which can save the mixing ratio data to a U disk for easy production quality control management;
9.Equipped with audible and visual alarms, it is convenient for equipment personnel to reach the faulty machine site quickly and accurately;
10.contacting parts on raw material are made of stainless steel, which can prevent the materials being polluted;
11.The gravimetric blender can be directly mounted on the injection machine or optional stand frame near the injection machine(including pneumatic discharge valve).

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