The invention and use of hammer crusher has a history of more than 100 years. Through continuous improvement and innovation, it is widely used in cement, coal preparation, thermal power generation, metallurgy (sintering and coking), refractory and other industrial sectors. Hammer crusher crushing materials by impact. When the material is fed into the crusher, it is immediately crushed by the hammer of the high-speed rotary crusher.

　　The hit material obtains kinetic energy from the hammer head and rushes up to the lining plate and grate bar on the inner wall of the casing at a high speed, resulting in the second crushing. The material smaller than the gap of the grate will be discharged from the gap, and the material with larger block size will bounce back into the rotary track of the hammer head and be crushed by the hammer head. Advantages: high productivity, large crushing ratio, simple structure, compact size, low power consumption, easy maintenance, repair and replacement of vulnerable parts, uniform product particle size, less over crushing. Disadvantages: hammer head, grate bar, lining plate and rotor disc wear faster, especially when crushing hard materials. When the moisture content of the crushed material exceeds 12% or contains clay, the gap of the grate bar is easy to be blocked, thus reducing the productivity and increasing the energy dissipation and the wear of hammer head and other parts.