Difficulty: Medium
Correct Answer: 0.087 * L * S
Explanation:
Introduction / Context:
Crusher sizing often uses empirical capacity correlations involving receiving and discharge opening dimensions. For jaw and gyratory crushers, a widely cited rule-of-thumb relates capacity to the product L * S multiplied by a constant.
Given Data / Assumptions:
Concept / Approach:
The correlation embodies average performance over typical operating ranges and bulk densities. It is not a replacement for detailed manufacturer curves, but it serves as a screening estimate in preliminary design and equipment comparison.
Step-by-Step Solution:
Write the empirical form: Capacity ≈ k * L * S.Use k ≈ 0.087 (ton·hr^−1 per cm^2) for jaw/gyratory crushers in standard units.Select '0.087 * L * S' as the correct expression.
Verification / Alternative check:
Comparisons with manufacturer specifications show reasonable agreement for mid-range settings; detailed sizing still requires feed characteristics and RPM.
Why Other Options Are Wrong:
0.01 * L * S underestimates; L * S or L * S / 0.087 grossly overestimate capacity.
Common Pitfalls:
Treating the correlation as exact without considering material friability, moisture, and crusher speed, which all affect throughput.
Final Answer:
0.087 * L * S
Discussion & Comments