Loss in Weight Feeders (Food Processing)

In gravimetric loss-in-weight feeding, a feeding device with a material hopper is placed upon a platform scale or suspension weighing system. The entire feeder and the material are weighed and as the feeder discharges the material, the resultant “loss –in weight” per unit of time is determined. The actual weight loss is compared to a desired feed rate. If a difference is detected, the weighing and control system adjust the speed of the feed device. Loss-in-weight feeders are the ideal choice when a long-term accuracy of 0.25 to 0.50% is needed. Most feeder types can be used as a loss-in-weight feeder, including screw feeders, vibratory feeders and liquid pumps on a scale. Loss-in-weight feeders can be used in the manufacture of almost all processed foods requiring high accuracy, including continuous feeding of multiple ingredients into an extruder or mixer, loss-in-weight batching and feeding into size reduction or coating processes.