Screen capacity (throughput) depends on many variables. Which of the following is generally not considered an intrinsic design/operation function for capacity estimation?
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AScreen opening size
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BScreening mechanism (vibration/rotary)
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CScreening surface area and type
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DAtmospheric humidity
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EInclination angle only
Answer
Correct Answer: Atmospheric humidity
Explanation
Introduction / Context:Screen capacity correlates with aperture, open area, vibration parameters, inclination, and feed characteristics. This question asks you to identify the parameter that is not an intrinsic design/operation variable in capacity equations.
Given Data / Assumptions:
- Standard sizing methods focus on mechanical and geometric factors.
- Feed moisture affects performance, but ambient humidity per se is not a direct capacity term.
- We assume normal industrial indoor/outdoor conditions.
Concept / Approach:Capacity expressions include aperture size, open area, vibration frequency/amplitude, angle, and bed depth. While humidity may influence feed moisture indirectly, it is not an explicit design variable like opening size or mechanism. Therefore, “atmospheric humidity” is not a capacity function in standard design correlations.
Step-by-Step Solution:List core design variables in capacity equations.Distinguish environmental conditions from intrinsic screen parameters.Identify atmospheric humidity as not directly used.
Verification / Alternative check:Vendor sizing charts and empirical formulas omit ambient humidity, focusing on screen geometry and motion.
Why Other Options Are Wrong:Opening size/mechanism/surface/angle: all key determinants of capacity.
Common Pitfalls:Confusing feed moisture (which matters) with ambient humidity as a standalone design variable.
Final Answer:Atmospheric humidity