Question

Equipment that separates the material based on length include(s)
(A). Indented cylinder separator
(B). Inclined draper
(C). Disk separator
(D). Rotary screen cleaner

Choose the correct answer from the options given below:

• A. (A) only.
• B. (A) and (B) only.
• C. (A) and (C) only.
• D. (B), (C) and (D) only.

Hint:

Remember the "length separators" in seed processing:
1. Indented Cylinder Separator
2. Disc Separator
Both utilize indent pockets designed specifically to lift shorter grains away from longer ones.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Granular mixtures are graded and separated using physical dimensions: width, thickness, and length.

Step 3: Detailed Explanation:
Let us review the separation principles of each equipment:
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Indented cylinder separator (A): Contains small, pocket-like indents on its internal rotating wall. Short grains fit into these pockets and are lifted higher into a collecting trough, while long grains slide down, achieving precise separation by length. Thus, (A) is correct.
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Inclined draper (B): Separates particles based on shape (round vs. flat) and surface friction, not length.
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Disk separator (C): Employs rotating vertical disks containing small pocket recesses that lift only shorter particles from the mixture. Thus, (C) is correct.
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Rotary screen cleaner (D): Separates particles by width or thickness using sized screen perforations.
Therefore, only (A) and (C) separate materials based on length.

Step 4: Final Answer:
The correct option is 3, which corresponds to (A) and (C) only.