Submitted to: Indian Textile Research Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/31/2003
Publication Date: 7/15/2003
Citation: Zeidman, M.I., Sawhney, A.P., Herrington, P.D. 2003. Fiber Migration Theory of Ring-Spun Yarns. Indian Textile Research Journal. 28(2):123-133. Interpretive Summary: A fundamental understanding of the structure of a ring-spun cotton yarn is important from the yarn quality standpoint. Fiber migration plays a significant role in the yarn structure. For many years, many researchers have advanced many theories on the fiber migration, yarn structure, yarn properties, and their interrelationships. Treloar-Hearle (T-H) theory of fiber migration has been considered more realistic in defining yarn structure than the numerous others. However, the T-H model also presents an inherent difficulty in its conclusion that the yarn core must be hollow and the fibers must develop kinks on the yarn surface, which does not hold up in case of staple-core cotton-wrap yarns developed and patented by USDA. We are presenting here a modified model of fiber migration, which states that some fibers in a ring-spun yarn migrate from the yarn surface to the yarn core in one half cycle and then back to the surface in the other half, while most fibers migrate from the surface inwards and then turn around to migrate outward before reaching the yarn axis (core). Although the fiber migration and the yarn mechanics are complex phenomena, we hope that this paper will contribute to the analysis and fundamental understanding of the structures of ring-spun cotton yarns and ultimately help those who are involved in the cotton research and production sector.
Technical Abstract: The well-known Trelor-Hearle (T-H) theory of fiber migration, although more realistic in defining the yarn structure than the helical model, however, suffers from certain internal inconsistencies such as singularities at the yarn core. The objective of this paper is to re-examine the theory of fiber migration and establish a new basis for the development of an improved model of ring-spun yarn structure with an emphasis on revisiting the fiber migration theory. Accordingly, the existing theories of Treloar and Hearle, et al., have been reformulated and combined in a way that is more accurate for predicting the structural dynamics of a yarn. This gives a more acceptable description of yarn structure, and hence, leads to more accurate predictive models of load-deformation behavior of the yarn. A relationship between the process parameters and the yarn structure is also suggested, which is important for the resulting yarn properties such as tensile strength, abrasion resistance, and twist torque. Although we realize that fiber migration and yarn mechanics are complex phenomena, we hope that this paper will contribute to the analysis and fundamental understanding of the phenomena.