A crusher is a machine that crushes large-sized solid raw materials to the required size. 

According to the size of the crushed materials or crushed materials, crushers can be divided into coarse crushers, pulverizers, and ultra-fine pulverizers. 

There are four external forces exerted on solids during the crushing process: shearing, impact, rolling, and grinding. Shearing is mainly used in coarse crushing (crushing) and pulverizing operations, and is suitable for crushing or pulverizing of tough or fibrous materials and large materials; impact is mainly used in pulverizing operations, and is suitable for pulverizing brittle materials; rolling It is mainly used in high-fineness crushing (ultra-fine grinding) operations, and is suitable for ultra-fine grinding operations of materials of most properties; grinding is mainly used in ultra-fine grinding or ultra-large grinding equipment, and is suitable for further grinding operations after grinding operations.  

The actual crushing process is often caused by several external forces acting at the same time, but high-end crushers are tailor-made according to the crushing environment.