22—a Comparison of the Properties of Open-End-Spun and Ring-Spun Yarns Produced From Two Egyptian Cottons

Abstract

A comparison bet%^een ihe qiialilies of open-end-and ring-spun yarns produced from Egyptian cottons is reporled. Yarns of different counts and twist faciors were produced on both the BD 200 opcn-end-spinning machine and a conventional ring-spinnmg machine and their qualily was studied by delermining their strength, uniformity, and number of imperfections. The quality ot open-end-spun yarn relative to that of ring-spun yarn is expressed in terms of the relative qualitŷ 'it°is shown that the percentage reduction in strength of open-end-spun yarns compared with that of ri ng-spun yarns can be minimized by spinning them to coarser counts from shorter cot^tons. This is attributed to the different interactions between the fibre properties and the mechanism ol yarn formation when ditVerent types of cotton are used... ., • . It is also shown ihat the relative quaiily of open-end-spun yarns can be considerably increased by spinning them to coarser counts from Ashmouni cotton. The quality of open-end-spun yarn can exceed that of ring-spun yarn when Ashmouni cotton is spun to a Imear density exceeding 30 tex.It isconciuded thai the BD 200 open-end-spinning machine cannot be recommended for spinning line yarns from long-staple Egyptian cottons. I. INTRODUCTIONIt is well known that open-end-spun yarns are inferior in quality to ring-spun yarns. and this has been attributed to the inferior structure of these yarns compared with thai of ring-spun yarns. The difference in structure between the two yarns has been investigated by several workers'--i and found to be a reflection of the different mechanisms of yarti formation of the two types of yarn. Because of this difference, the interaction between fibre properties and the mechanism of yarn formation on the open-end-spinning machine is expected to be different from that on the ring-spinning machine. In other words, whereas long-staple Egyptian cotton is ideally suited to the ring-spinning machine, which contributes to a superior yarn structure, it may not react in the same way on the open-endspinning machine. It was the aim of this study-^ to find out whether long-staple Egyptian cottons are. as in ring-spinning, suitable for spinning ftne yarns on the BD 200 open-endspinning machine. It was also hoped to determine the recommended range of counts and the type of cotton that would provide open-end-spun yarns with a quality not much lower than that of the equivalent ring-spun yarns. It was felt that this would help in utilizing the potential quality of Egyptian cottons on the BD 200 machine.

Qualidade do fio "open-end" obtido com matérias-primas produzidas por variedades paulistas de algodoeiro e suas misturas com poliéster

“…A "open-end" não é recomendada para fios finos obtidos com algodões de fibra longa (7). Bons resultados para resistência desse fio podem ser conseguidos, utilizando-se fibras de algodão de baixo valor Micronaire e de alta resistência (I, 6).…”

The Role of Sheath Fibers in Influencing Twist Loss in Rotor Spinning

“…It was thought that the core fibers do not slip much. Sultan and El-Hawary [8] visualized slippage between the condensed fiber strand and the collecting surface of the rotor. Dyson [I], who also agreed.…”