Question

Which spinning system produces yarn directly from sliver without roving?

• A. Ring spinning
• B. Rotor spinning
• C. Mule spinning
• D. Cap spinning

Hint:

Rotor spinning increases productivity by eliminating the roving stage and is widely used for coarse yarn production.

Answer 1

The Correct Option is B

The question pertains to the method of yarn production in textile manufacturing, specifically focusing on the spinning systems that convert slivers directly into yarn without the need for roving. Let's evaluate the given options:

1. Ring Spinning: This traditional and widely used spinning method involves drawing out the roving into a fine yarn and adding twist through a spinning spindle. Since it uses roving, it is not the correct answer.
2. Rotor Spinning (Open-End Spinning): This is a modern spinning technique that produces yarn directly from slivers. The sliver is fed into a rapidly rotating rotor, where fibers are collected and twisted to form yarn. It bypasses the roving process, making this the correct answer.
3. Mule Spinning: An older technology, which alternates between drawing out and twisting the roving into yarn. It requires roving and is therefore not applicable.
4. Cap Spinning: Similar in principle to ring spinning, this process also requires roving for yarn production, and thus, is not the correct answer.

Thus, the correct answer is Rotor spinning, as it directly processes the sliver into yarn without the intermediary roving stage. The efficiency and simplicity of rotor spinning make it an advantageous option in modern textile manufacturing.

Answer 2

Step 1: Understanding the spinning sequence.
In conventional spinning systems, fibres pass through several stages such as carding, drawing, roving, and spinning. The roving stage is mainly used to reduce sliver thickness and insert a small amount of twist before final yarn formation.
Step 2: Concept of rotor spinning.
Rotor spinning, also known as open-end spinning, is a modern spinning method in which yarn is produced directly from sliver. The sliver is opened into individual fibres and collected in a rapidly rotating rotor where yarn formation takes place.
Step 3: Analysis of options.
(A) Ring spinning: Requires a roving stage before yarn formation and cannot spin directly from sliver.
(B) Rotor spinning: Correct — It eliminates the roving process and produces yarn directly from sliver.
(C) Mule spinning: An intermittent spinning process that uses roving as an intermediate material.
(D) Cap spinning: A modification of ring spinning that still requires roving.
Step 4: Conclusion.
Since rotor spinning directly converts sliver into yarn without the need for roving, it is the correct answer.