Effect of Multiple Sheath Rovings on Cotton Core-Spun Yarn Structure: a Comparative Analysis of Roving Distances

This study investigates the impact of varying roving distances in multi-sheath core-spun yarn production by feeding three individual staple rovings into the drafting zone. Specifically, the distance between the sheath rovings was kept constant for the symmetric core-spun yarn (SYCS) and varied for the asymmetric core-spun yarns (ASYCS). Filaments were fed along with the staple in the middle. In addition, siro core-spun yarns were produced (SCS). A comprehensive analysis of the physical, structural, and mechanical properties of the yarns was conducted, including measurements of yarn packing density and the core/sheath ratio. The experimental results revealed that roving distances influence the positioning of fibers within the yarn structure, with SYCS yarns exhibiting a higher packing density than ASYCS yarns. Furthermore, increasing roving space for ASYCS yarns reduced hairiness by 23.1% (for S3) and decreased yarn strength by 5%. No statistically significant differences were observed for the unevenness values. These findings highlight the effect of roving positioning on yarn properties for multi-sheath yarn production, offering valuable insights for optimizing composite yarn properties in technical and high-performance textile applications, such as those used in automotive, aerospace, and lightweight composites.