The working principle of the sand making machine is to crush the materials by using the plate hammer installed on the high-speed rotating rotor, and then accelerate the crushing of the materials by using the mutual friction between the materials, and finally discharge the crushed materials from the lower discharge port. In the whole crushing process, the materials themselves impact and crush each other, instead of directly contacting with metal elements, they impact and rub with the material lining, which reduces the angular pollution and prolongs the mechanical wear time. The ingenious air flow self-circulation in the vortex cavity eliminates dust pollution. Therefore, it is suitable for coarse crushing and fine crushing of ultra-hard, medium hard and poor abrasiveness materials.