Classification system

The utility model discloses a grading system. The grading system comprises a grading machine, a cyclone collector, a dust remover and an induced draft fan, the grader comprises a cylinder body and a grader body, the feeding hole is formed in the lower part of the cylinder body; a first conveying pipeline; the grading functional area comprises a grading cavity, a plurality of motors and a plurality of grading impellers; the fine material outlet is formed in the upper end of the grading functional area; the coarse material outlet is formed in the lower end of the grading functional area; a first air supplement area, a second air supplement area and a coarse material discharge port. During use, the multiple motors and the grading impellers are arranged, the grading capacity is improved, meanwhile, the first air supplementing area and the second air supplementing area are used for carrying out second-time grading treatment and third-time grading treatment on graded coarse particles through natural air, energy con