r = F₈₀ / P₈₀F₈₀ and P₈₀: sizes at 80% passing, in the same unit.
Use when: Reduction ratio defined from distributions, not just the largest block.
Ore crushing
Understanding primary fragmentation and the choice of a crusher.
What is happening?
Crushing reduces blocks by compression, impact or other mechanical stresses. Jaw, gyratory and cone crushers do not act exactly the same way.
The output setting influences the particle size and capacity, but the product has a size distribution. Reducing the aperture guarantees neither a one-size-fits-all nor unlimited flow improvement.
The formulas, with their conditions.
Qmassique = m / Δtm: t; Δt: h ; Q: t/h.
Use when: Measure the mass actually processed over a defined interval.
Where is this principle used?
Ore preparation plant
Reduce the blocks before grinding and concentration.
Aggregates quarry
Prepare size classes for construction and roads.
What to observe in the experiment
Modify the discharge opening and compare P₈₀ and flow rate, keeping the same feed ore.
References and readings
This sheet explains the principles and their assumptions. Educational simulation can simplify the process; an industrial model requires suitable data and validation.
Have you understood the essentials?
Only one correct answer per question. Answer all three questions, then view the answer key.
Intu Lab · Understanding sheet · Kimba Christian