Crushing

Crushing is a material size reduction process in which solid materials are reduced in size by applying mechanical force, typically through compression, impact, or a combination of both. It is a primary step in many industrial workflows and is distinct from grinding, which generally produces finer particles. The term encompasses various methods and equipment used to break down large blocks into smaller fragments suitable for handling, transport, or subsequent processing.

In mining and mineral processing, crushers reduce ore and rock to smaller sizes for transport and for milling and separation. Primary crushers handle large blocks, while secondary and tertiary crushers refine material to products suitable for grinding or direct use. Common types include jaw crushers (compression between moving and fixed plates), gyratory crushers (spindle and concave configuration), cone crushers (cone-shaped mantle and concave), and impact crushers (blow bars or plates that impart high-velocity impact). Other devices such as hammer mills and vertical shaft impactors serve specific reduction needs. Mobile crushers are frequently employed for on-site processing in quarries and construction projects.

Applications span several sectors. In construction and aggregates production, crushing yields gravel and crushed stone for roads, concrete, and building materials. In mining, it enables ore to be milled and separated efficiently. In recycling, crushers reduce concrete, glass, and other materials for reuse. In food and pharmaceutical processing, crushing or milling breaks down ingredients and active substances to aid mixing, extraction, or formulation.

Safety and environmental considerations are integral to crushing operations. They generate dust, noise, and vibration and consume substantial energy, necessitating dust control, sound attenuation, proper ventilation, and energy management. Equipment maintenance, guarding, lockout/tagout procedures, and adherence to safe operating practices help prevent injuries and equipment failures.