Vertical crushing machine CGM-20 with cooling air system and high speed rotation. Dedicated for mineral, fiber and adhesive substances. Wind is used to cool the grinder for continuous operation. Time attrition depends on the material to be shredded. Laboratory crushing machine is equipped with a set of three blades: Straight blade- use for the materials in general, fiber, and tough quality such as pearl, gentian and liquorice, Big curve blade- use for the materials in powder, fiber, and viscosity quality such as gentian and medlar, Medium curve blade- use for the materials that straight blade can not pulverize. Or when use the big curve blade but can not achieve the tiny powder, use this blade.