Influence of yarn extension on longitudinal structural characteristics of fibres

Abstract

A detailed study on the effect of progressive yarn extension on longitudinal structural characteristics of fibres has been reported in the present paper. An image processing-based system to characterise and visualise the configuration of fibres in yarn under extended mode has been adopted. A detailed study has been reported on the changes in longitudinal structural characteristics of fibres, such as fibre extent, fibre strain, straightening and slippage of fibres, fibre-pair-overlap length (FPO) and fibre-overlap index (FPI), during axial extension of ring-spun yarn. The actual length of fibre and the fibre extent in the yarn were found to be increased with the increase in yarn extension. With yarn extension from 0 to 4% the fibre strain in the yarn becomes moderate and further increase in yarn extension from 4 to 8% the fibre strain reduces, but with further increase in yarn extension of 8–12% the fibre strain again increases. It has also been observed that the fibre straightening percentage at different intervals of yarn extension is not the same and it decreases with the increase in yarn extension. The fibre slippage percentage is also not the same at different intervals of yarn extension percentage. It is found to be maximum at 4–8% and minimum at 0–4% yarn extension.