A secondary impact crusher is a mechanical device used in aggregate production, mining, and recycling industries to reduce the size of materials. It operates after the primary crushing stage, aiming to refine the material into finer particles and enhance the final product quality.

Working Principle:
Secondary impact crushers function through the interaction between a high-speed rotating rotor (equipped with hammers or blow bars) and fixed/adjustable impact plates. When material enters the crushing chamber via the feed hopper, it is hurled by the rotor toward the impact plates, where repeated collisions break it down until the desired size is achieved.

Applications:

  • Mining: Crushing hard and medium-hard rocks (limestone, granite, basalt).

  • Construction: Recycling concrete, asphalt, and demolition debris.

  • Aggregate Production: Producing optimally sized aggregates for road construction or concrete.

Advantages:

  • High Efficiency: Rapid crushing due to rotor speed and impact force.

  • Adjustable Output: Particle size control via interchangeable impact plates and screens.

  • Cubic Product Shape: Impact mechanism creates angular, cubic grains ideal for high-strength concrete.

  • Dust Reduction: Minimizes dust generation when processing moist materials.

Example Use Cases:

  • Reducing 150 mm material from a primary crusher to 20 mm.

  • Processing recycled concrete for reuse in new construction.