The onions are spread out on the first sieve, which has small holes. The larger diameter product passes on until it falls through the sieve of adequate size, or into the over size.
A vibrator causes the product to advance.
Collection hoppers are placed below the lines, according to the number of size grades to be obtained. The hoppers unload onto bi-directional exit belts that take the product directly to bins, or if requested, onto scales equipped with load cells.
A frame with rubber pads on it moves under the sieves with an alternating motion to keep the holes clear
The sieves are supplied with holes sizes according to the customer’s request.
Standard version: 4 sizes + over size.