关键词: 尖端, 磁铁矿石, 冲击, 破碎

Abstract: How to reduce the grinding energy consumption of magnetite ore is a major issue in the industry. Aiming at the high irregularity of appearance shape in the production process of magnetite ore，the influence of tip shape on crushing characteristics is clarified，which provides theoretical support for reducing crushing energy consumption. The tip shape of magnetite ore was extracted by HOG feature extraction method，and the impact crushing test of magnetite ore with different tip shapes was carried out by using the guide rod drop hammer impact test system. The research showed that the tip shape extracted by HOG image feature extraction method is single edge，three edge and flat edge. The tip protrusion promotes the impact crushing，and the tip part and the bottom corresponding to the tip are destroyed first，which is the initial point of destruction and gradually spreads to other parts. The impact force time history curve of the tip magnetite ore is mainly divided into the high-amplitude rapid oscillation stage of the impact force and the stable stage of the impact force oscillation. The low-tip protrusion impact force is the most significant in the highamplitude rapid oscillation stage，and the increase of the tip protrusion promotes the impact force oscillation to be gradually significant in the stable stage，and has good impact stability. With the increase of slope amplitude of single edge magnetite ore，the stable stage of impact force oscillation is gradually significant.

Key words: tip, magnetite ore, impact, crushing