175 Model Grain De-stoner have greatly higher capacity basic on the model of 125 Grain De-Stoner, through optimization of the screen and transmission parts.This De-stoner is designed for effective removal of stones and iron, dirt, glass and other heavy impurities from crops, i.e. sunflower seeds, kernels, water melon seeds and wheat, etc. The materials passes on an inclined vibration screen with fish-skin. Materials and high density waste are separated using upward current air passed with the help of a dust removal. The heavy impurities (stones) fall through the air stream and are discharged from stone outlets. Grains suspended then sink down to grains outlet. Air volume and angle of screen can be adjusted to meet an optimal degree of separation according to different materials, and matched with cyclone can achieve the best processing effect. In addition, the excellent removal of high-density impurities like stones protects the downstream processing equipment and thus perceptibly reduces its wear and tear.