Gravimetric Dosing System Equipment principle
A gravimetric blender has two or more hoppers arranged above a weigh-pan which is controlled by a very sensitive load cell. And the hoppers will open and close under control of the slide-gate valve. Once the blender is turned on and the recipe is selected, it will dose and mix materials automatically.
For instance, if you select recipe A which is comprised of natural resin 90%, regrind 8%, color 2%, and you preset the batch weight as 1000g, then the PLC inside the blender will control the open/close of the hopper valves in order. First natural resin hopper open and resin flows down into the weigh-pan until it reaches 900g, then the valve closes. Secondly, the regrind hopper valve opens and regrind flows down into the weigh-pan until it reaches the amount of 80g, then the valve closes, and the same as the color. 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. Weighing Scale Mixer | 
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