关键词: 喷气涡流纺, 包芯纱, 纺纱段张力, 覆盖系数, 纱线性能

Abstract: Air-jet vortex spinning technology is characterized by a short production process, high speed and efficiency, as well as low labor requirements. Additionally, the yarns produced exhibit low hairiness, good abrasion resistance, and resistance to pilling. However, the yarn strength is only about 80% of that of ring-spun yarns. Producing core-spun yarns using air-jet vortex spinning equipment not only retains the advantages of vortex spinning but also leverages filament yarns to enhance yarn strength. This approach compensates for the lower strength of air-jet vortex-spun yarns while preserving the characteristics of the outer fibers, making it practically significant for improving yarn performance.
This study primarily focuses on 17.2 tex air-jet vortex-spun viscose/nylon/polyester filament core-spun yarns as the research object, conducting single-factor experiments on core filament pre-tension and feed ratio. Under a feed ratio of 0.98, five tensioner settings (levels 1–5) were selected to produce samples. At tensioner level 4, feed ratios of 0.94, 0.96, 1.0, and 1.02 were chosen for sample production. The study focuses on the effects of core filament pre-tension and feed ratio on the tension distribution of different components in the air-jet vortex-spun core-spun yarn. It further explores how these tension changes influence yarn structure, coverage performance, and yarn quality, with the ultimate goal of optimizing the final yarn quality. For evaluating the coverage performance, black core filaments were used during spinning to facilitate the observation of exposed filaments. Single-sided images of vortex-spun core-spun yarn were processed using threshold segmentation. Appropriate thresholds (75 and 145) were applied to segment the images, allowing the measurement of the exposed core filament area on one side and the total yarn area. The coverage coefficient was then calculated to quantitatively analyze the coverage performance of air-jet vortex-spun core-spun yarn.
The study results indicate that the spinning segment tension of air-jet vortex-spun core-spun yarn is jointly influenced by the feed ratio and core filament pre-tension, showing a positive correlation. The ratio of core filament tension to wrapping fiber tension in the spinning segment significantly affects the yarn structure. When the ratio is too low, the core filament tends to bend and form loops, whereas when the ratio is too high, the outer wrapping fibers are prone to peeling and forming loops. Furthermore, excessively high or low ratios result in asynchronous breaking of the components in the air-jet vortex-spun core-spun yarn, leading to multiple peaks in the stress-strain curve. At a feed ratio of 0.98 and a core filament pre-tension of 2.1 cN, the structure of the 17.2 tex air-jet vortex-spun viscose/nylon/polyester filament core-spun yarn is the most stable, exhibiting the highest coverage coefficient and breaking strength, with fewer hairiness and the best evenness. Within a certain range, higher feed ratios and core filament pre-tensions result in greater breaking elongation. The optimized 17.2 tex air-jet vortex-spun viscose/nylon/polyester filament core-spun yarn shows improved yarn performance compared to air-jet vortex-spun viscose/nylon blended yarn of the same specification.

Key words: air-jet vortex spinning, core-spun yarn, spinning section tension, coverage factor, yarn property