Horizontal Shaft Impact Crusher

Horizontal Shaft Impact Crusher

The horizontal shaft impactor (HSI) has a shaft that runs horizontally through the crushing chamber with a rotor that turns hammers or blow bars. It uses the high speed impacting force of the turning blow bars projections to break the material. With impact crushing, the material breaks along its natural cleavage lines, resulting in a more cubical product at high reduction ratios. Horizontal shaft impactor can be used as primary or secondary crushers. In the primary stage, horizontal shaft impactors are better suited for softer and less abrasive material. In the secondary stage, the horizontal shaft impactors can process more abrasive and harder material. 

In compression crushing (primary gyratory, jaw crusher and cone crusher) the material is squeezed between 2 surfaces which get closer to each other. The crushing movement speed is between 0.5 m/s up to 1.5 m/s. In impact crushing (Horizontal Shaft Impactor - HSI and Vertical Shaft Impactor - VSI) the material is subject to shocks given by rotating parts (rotor equipped with blow bars, etc.) and thrown against metal surfaces. The movement speed is from 30 up to 80 m/s. 

Horizontal shaft impactors are suitable for crushing hard rocks such as limestone, dolomite, granite and other similar materials under toughest operating conditions. 

A reversible impactor generally uses hammers instead of blow bars and the material hits the breaker blocks/plates instead of aprons liners. 

However, the horizontal shaft impactors and hammer mills cannot be used for clay bearing or sticky materials as the crushing chamber will build up with the clay (sticky material) and prevent impact crushing from taking place. The crushing chamber will also quickly pack.