Food Size Grader Machine Manufacturers

Food size grading machines — types and applications

Size grading separates a product stream into size fractions based on physical dimensions. The main size grading machine types for food applications are: diverging roller graders (pairs of diverging rollers that are spaced progressively wider along the machine — small items fall through the gap when it matches their diameter; large items travel to the end; standard for citrus, mangoes, apples, and other round or oval fruit); vibrating screens (flat or inclined mesh screens that vibrate — undersize material falls through the mesh aperture; oversize is retained; suitable for grains, seeds, nuts, and cut vegetable pieces); trommel screens (a rotating cylindrical screen — small material passes through the screen perforations; large material exits from the open end of the drum; suitable for potatoes, onions, and root vegetables); and sieve graders (multi-deck vibrating sieves with progressively finer apertures — standard for grain and seed sizing into multiple fractions in one pass). The choice of size grading technology depends on the product shape, the required number of size fractions, and the throughput.