When choosing a crushing and formulating crushing technology, we should first lean the performance of solid materials. The performance of materials is paramount for the selection of crushers and powder grinding mill as it will directly influence the crushing effect of materials, energy consumption of crusher machine, granularity property of crushed products, abrasion of main crushing spare parts of crusher equipment as well as the special measures that must be taken in the crushing process. When choosing a crusher, the following basic performance of solid materials must be considered:

Geometrical features of solid material include particle size, particle shape, specific surface area and porosity which means the size and voidage of the internal space of materials.

Physical properties of solid materials include handling characteristics of material, flowing property, frictional property and other prosperities such as hardness, density, bridging property, dispersibility and aggregation.

Chemical property of solid materials includes chemical composition, decomposition, hygroscopicity, corrosivity, flammability, virulence and explosiveness and electrical property includes electrical conductivity, magnetism and static electricity.

Before the design of material crushing, the following physical data must be obtained: bulk density, hardness, granularity composition and biggest granularity of materials to be processed; whether materials have virulence and whether the dust has explosion hazard; the grinding and corrosive degree of the crushing parts by the materials to be crushed on crushing machinery and the stickiness property of materials. A suitable crusher machine should be chosen according to the physical data and relevant property of materials.