Open end spinning:
Open end spinning includes different types of system:
- Rotor spinning
- Friction spinning
- Vortex spinning
- Axis spinning
- Mule spinning (continuous)
Among the systems mentioned above, Rotor spinning has higher popularity than others.
Rotor spinning system:
By the advent of Rotor spinning the cost of production has reduced and on the other hand, the speed has increased efficiently. In Ring spinning system spindles could rotate at speeds up to 25,000 rpm which makes the yarn twisted and ring rails movement guides the thread onto the bobbin into the shape required, these processes are high energy consuming and reduce the speed. In Rotor spinning system by having a shorter product line, fewer operator and less needed energy the final cost of products reduces.
Main parts of the Rotor spinning system:
Feed roller and feed plate
In Rotor spinning system the feed is sliver and the product is Rotor yarn. At the first stage, the sliver passes through the sliver guide, and then passes among feed plate and feed roller. The opening roller is after the feed plate and rotates rapidly and separates the fibers, by the transport channel, separated fibers enter the rotor and start to rotate. In the rotor, fibers start to fall down into the central groove because of the Centrifugal forces and vacuum in the rotor and fibers are collected there to form fibers ring. At the yarn formation stage, a spun yarn end emerges in the groove. The yarn end rotates around its axis and continuously twists-in the fibers deposited in the rotor groove, by these actions fibers continuously go into the yarn structure and the yarn which is formed in the rotor is continuously taken off.
In the rotor spinning the diameter and the speed of the rotor and opening roller are adjustable and this is very important that the speed of entrance and output should be same; in otherwise the yarn would break.
Properties of rotor yarn compared to the ring yarn:
|Ring yarn||Open end(Rotor yarn)|
|Higher breaking strength||Higher elongation at break|
|Better handle||Harder handle|
|Higher hairiness||Lower hairiness|
|Higher smoothness||Higher abrasion resistance|
|Higher luster||Greater volume|
|Higher ability for absorbing dye and water|
|Higher cover coefficient|
End usages for open end yarn:
Corduroy, velveteen, rain wear, denims, sheets, pillow cases, bed spreads, printed fabrics, curtains, upholstery, carpet, blankets, towel.