Question

Yarn that has helically twisted fibres at the core and belts/wrappers on the surface is

• A. Ring yarn
• B. Rotor yarn
• C. Compact yarn
• D. Air-vortex yarn

Hint:

Rotor yarn is distinct for its core and wrapper structure, which gives it a unique combination of strength and flexibility.

Answer 1

The Correct Option is B

The yarn with helically twisted fibres at the core and belts or wrappers on the surface is called Rotor yarn. Rotor spinning is a modern and efficient spinning technique that involves spinning fibres into yarn using a high-speed rotor. In this method, the fibres are fed into the spinning chamber, where they are twisted into yarn by the action of the rotor. Rotor yarns are known for their structure where the fibres at the core are twisted helically, and they are wrapped with an outer layer of fibres. This structure gives rotor yarn its characteristic properties such as strength, elasticity, and a unique texture.
- Ring yarn, on the other hand, is produced using the traditional ring spinning method, where the fibres are twisted into a yarn by a rotating spindle. Unlike rotor yarn, the ring spinning method does not produce the same kind of structure with a twisted core and surface wrappe.
- Compact yarn is a modified version of ring yarn, where the fibres are compressed together before being twisted, giving it a smoother and stronger texture, but it does not have the core-and-wrapper structure like rotor yarn.
- Air-vortex yarn is produced using a jet of air that twists the fibres around a core, which can also lead to the formation of yarn with a different structure, but it does not specifically involve the same twisted core and surface wrappers as rotor yarn.
Thus, the correct answer is:
\[ \boxed{\text{(B) Rotor yarn}}. \]