Screening machines utilize the differences in material size and quality, along with variations in liquid settling velocity, to allow smaller and larger materials to settle to the bottom.
Grading screens use a spiral to push material upwards for mechanized screening. This allows for the filtration of materials from the mill according to their grade. Larger materials are then fed back into the mill's feed inlet using spiral blades, while the filtered smaller materials overflow from the overflow pipe. The base of the grading screen is made of channel steel, and the body is welded from steel plates.
