wherein fibers can be collected and then drawn off as a yarn. For short staple spinning, most rotors are 31 to 56 millimeters in diameter and may contain a shallow "U" or "V" shaped fiber alignment groove around their periphery. In open end spinning, the rotor rotation provides the twisting force.
Twist has traditionally been inserted into yarn by rotating the package upon which the yarn is being wound. In the case of open-end spinning, the twisting force is generated by the rotation of a rotor and is transmitted by friction to the fibers that make up the tail of the newly-formed yarn. As this twisting tail comes into contact with other fibers, it collects them. Once this process is started, it is self-sustaining, and yarn can then be drawn out of the rotor continuously. In order to prevent twist from being transmitted throughout the length of the fibers that are available for collection into yarn, it is necessary that these fibers not be in any significant frictional contact with one another. It is from this requirement, that the supply fibers not be in intimate frictional contact, that open-end spinning derives its descriptive name. This lack of contact allows true twist to be inserted into the yarn, and at the same time, prevents twist from being transmitted throughout the fiber supply, which would result in instant stripping of the rotor.
The basic difference between ring-spun yarns and open-end spun yarns is in the way they are formed. The former produces yarn by inserting twist into a continuous ribbon-like strand of cohesive fibers delivered by the front rolls, while the latter forms yarn from individual fibers directly by collecting them from the inside surface of a rotor by twist forces. Thus, for comparison, it could be said that a ring yarn is formed from the outside in, while open-end yarn is formed from the inside out.
The elements basic to production of open-end
yarns are somewhat different from ring spinning.
a) Fiber supply
b) Drafting system
c) Fiber collection and alignment
d) Twist insertion -- yarn formation
e) Package winding
Spun yarn luster
Luster refers to the degree of light that is reflected from the surface of a fiber or the degree of gloss or sheen that the fiber possesses.
- Full dull