Spiral-style classifier machine is ​​simple in the construction design; and is convenient to operate, grading slot has a larger tilt angle for easy gravity connection with the mill. Dubbed the closed loop process points-way diversion of mineral sands, or in the gravity concentrator, grading ore and fine mud or metal beneficiation process on the slurry particle size grading, and washing the ore operations in the concentrator and mill off mud, dehydration and other operations.