Effect of the selected machine variables on the structural characteristics of air-jet spun yarn

Abstract

We investigate the manner in which the delivery speed and spinning air pressure of Rieter air-jet spinning machines affect the structural characteristics of viscose air-jet spun yarn (wrapper-fibre ribbon width, wrapper-fibre ribbon helix pitch, wrapper-fibre angle with respect to the yarn axis, yarn diameter, yarn packing density and number of wrapper fibres in the yarn cross section). The structural characteristics of the yarn were determined using an optical camera and by analysing the cross-sectional images and the longitudinal views of yarns. The results indicate that the frequency ratio of wrapper fibres varies from 0.21 to 0.26 and is independent of the delivery speed and spinning air pressure. However, these machine variables significantly influence the inner structure of the yarn, especially the wrapper-fibre angle with respect to the yarn axis and the yarn packing density. These characteristics are discussed with respect to the yarn tenacity and hairiness.

Keywords:

• Air-jet spun yarn
• machine variables
• structural characteristics
• wrapper fibres
• yarn packing density

Acknowledgements

We would like to specially thank Šárka Hajská for conducting some measurements.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1 Hereinafter, ‘wrapper-fiber angle’ means the angle with respect to the yarn axis.

Additional information

Funding

This work was supported by the Technical University of Liberec under Student Grant Scheme SGS 21303.