Question

The amplitude of drafting wave depends on
A. draft
B. hank number
C. settings of drafting rollers
D. immature fibres Choose the correct answer from the options given below:

• A. A, B, D only
• B. A, C, D only
• C. B, C, D only
• D. A, B, C only

Hint:

Drafting waves are a "mechanical" phenomenon. If you want to reduce them, you usually adjust your roller settings or reduce the draft.

Answer 1

The Correct Option is D

Concept: Drafting waves are periodic variations in the thickness (linear density) of a fiber strand caused by the uncontrolled movement of "floating" fibers during the drafting process.

Step 1: Analyzing Mechanical and Material Factors.

• A (Draft): The total draft significantly affects the wave; higher drafts generally increase the amplitude of drafting waves because the fibers are stretched more aggressively.
• B (Hank number): The fineness of the input material (hank) dictates the number of fibers in the cross-section, which influences drafting stability.
• C (Settings of drafting rollers): The "roller nip" distance is critical. If the distance between rollers is too wide for the fiber length being processed, a larger number of fibers become "floating" fibers, leading to higher drafting wave amplitude.

Step 2: Exclusion.
D (Immature fibres) affects dye uptake and can lead to neps, but it is not a primary mechanical factor that determines the physical amplitude of a drafting wave compared to the geometric and mechanical settings of the drafting system.