Effects of some process parameters on the structure and properties of vortex spun yarn

The effects of a number of process parameters, including the nozzle angle, nozzle pressure, spindle diameter, yarn delivery speed, and distance between the front roller and the spindle, on the structure and properties of vortex spun yarns were investigated. A modified version of the tracer fiber technique (J. Text. Inst., 43, T60-T66, 1952) combined with the Image Analysis Application Version 3.0 (B.A.R.N. Engineering) was utilized to explore yarn structure. The migration behavior of fibers was characterized using the migration parameters introduced by Hearle et al. (Text. Res. J., 35, 329-334,788-795, 1965). The results showed that the short front roller to the spindle distance caused better evenness, low imperfections, and less hairiness. High nozzle angle, high nozzle pressure, low yarn delivery speed and small spindle diameter reduced hairiness as well. High nozzle angle, high nozzle pressure and low speed also led to higher fiber migration. Surprisingly nozzle angle, nozzle pressure or delivery speed did not have any significant effects on yarn tensile properties. This is believed to be caused by the relatively small differences between the levels of these parameters used in the trials. The present study provides a window into the vortex spinning technology, but further research needs to be conducted to establish a process-structure-property model for vortex yarns.