Bulk solids handling — short-distance conveying of granular materials For short-distance transport of grain, gravel, sand, ash, or asphalt, which conveyor type is most commonly used?
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Aflight
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Bslat or drag
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Cribbon
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Dscrew
Answer
Correct Answer: screw
Explanation
Introduction / Context:Choosing a conveyor depends on material properties, distance, incline, and containment needs. For short runs inside plants, a compact, enclosed, and versatile unit is preferred for granular or powdery materials.
Given Data / Assumptions:
- Materials: grain, gravel, sand, ash, asphalt (granular to fine, sometimes hot).
- Short-distance conveying within a facility.
- Desire for enclosed transport to limit dust and spillage.
Concept / Approach:Screw conveyors are ubiquitous for short distances. They are simple, enclosed, tolerant of a range of bulk densities, allow controlled feeding, and can be inclined modestly. Alternatives like drag (slat) or flight conveyors serve niche layouts but are bulkier or more maintenance-prone for general short-run duties.
Step-by-Step Solution:Match requirements (short, enclosed, versatile) → screw conveyor.Check material compatibility: screws routinely handle grain, sand, ash, and even warm asphalt with proper materials of construction.Select “screw.”
Verification / Alternative check:Vendor catalogs list screw conveyors for metering and transfer over spans typically up to 30–40 m per section, ideal for “short distance.”
Why Other Options Are Wrong:
- Flight and slat/drag: workable but often chosen for abrasive, long, or vertical lifts; more complex casing and chain wear.
- Ribbon: a screw variant used to mix/handle sticky materials; not the generic transfer solution.
Common Pitfalls:
- Assuming belt conveyors are always preferred; belts excel at longer distances and higher capacities but are not listed among the options here.
Final Answer:screw