Rotary crusher is an equipment used in laboratory and small and medium-sized industrial production for fine crushing of medium and low hardness materials (such as ores, rocks, coal samples, ceramics, plastics, etc.). Its core function is to quickly crush block or granular materials to millimeter level (usually 0.1-5mm) through the action of "high-speed impact and shearing of rotary blades", providing uniform and small samples for subsequent component analysis (such as X-ray fluorescence detection, chemical analysis), particle size grading or process testing. Its characteristics are high crushing efficiency, low sample pollution, and convenient operation. It is widely used in geological exploration, coal detection, building materials, chemical industry, environmental protection and other fields.
The crushing process of the rotary crusher relies on the synergistic effect of high-speed rotary blades and fixed lining plates. The core structure and principle can be disassembled into the following three steps:
Feeding and Guidance: Block shaped materials (which need to be processed by coarse crushing equipment such as jaw crushers to ≤ 50mm) enter the crushing chamber through the feeding port. The guiding structure (such as a guide plate) inside the feeding hopper evenly guides the materials into the crushing area to prevent material accumulation.
Impact and shear crushing: The crushing chamber is equipped with high-speed rotating blades (usually 3-6 blades, made of high manganese steel, tungsten carbide or stainless steel, depending on the hardness of the material), which are driven by a motor (usually at a speed of 1000-3000r/min) to generate large centrifugal and impact forces. When the material comes into contact with the rotary blade, it will be rapidly impacted by the rotary blade onto the fixed lining plate on the inner wall of the crushing chamber. At the same time, the gap between the rotary blade and the lining plate (adjustable, determining the discharge particle size) will produce shear and compression effects on the material, and the material will be quickly crushed under the dual force.
Screening and discharge: The crushed material needs to pass through the screening device at the bottom of the crushing chamber (such as metal mesh, grille) - fine materials that meet the particle size requirements pass through the mesh and are collected through the discharge port; Coarse materials that do not meet the standards will be picked up again by the rotary blade, and the crushing process will be repeated until the particle size requirements are met.
Key to daily maintenance
Regularly inspect vulnerable parts: rotary blades, liners, and screens are vulnerable parts that need to be checked for wear every week (such as whether the edges of the rotary blades have become dull and whether the screens are damaged) - if the rotary blades are severely worn, they need to be replaced in a timely manner (otherwise the crushing efficiency will decrease by more than 30%).
Lubrication and maintenance: Add lubricating oil (3 # lithium based grease for motors and gear oil for gearboxes) to the motor bearings and gearbox (if any) every month to avoid overheating caused by dry friction of components.
Motor protection: It is strictly prohibited to forcibly start the equipment when it is stuck. If the motor trips due to overload, the stuck material should be cleaned first, and the motor should be allowed to cool down (about 10 minutes) before restarting to prevent it from burning out.
Long term storage: If the equipment is not used for a long time (more than one month), the residual materials in the crushing chamber should be cleaned, rust proof oil (carbon steel parts) should be applied, and a dust cover should be covered to prevent moisture and rust.