Effects of directed movement of fibres in a twist triangle on yarn quality

This work investigates the effect of directed flow of the fibres in a twist triangle on yarn properties. This is done using different clip-on attachments positioned on the front rollers of a ring spinning frame. Seven sets of rollers (plain non-grooved; 75 degrees-biased left-to-right grooved; 75 degrees-biased right-to-left grooved; 15 degrees-, 45 degrees- and 75 degrees-biased grooved from both sides towards the centre and solo) are made and positioned immediately below and parallel to the top front draft rollers of the laboratory ring spinning frame (tester model 82 KA) so that they can interact with the emerging drafted fibre strand before twist insertion. Afterwards, a 0.495-ktex (2.02 Nm) finisher worsted roving composed of 55% polyester and 45% wool is fed into each unit of the ring spinning frame to produce a yarn with a yarn count of 30 Nm and a twist factor of 125. The rollers affect the flow of the fibres in the triangle zone and, as a result, the quality of the yarns is affected. A comparison of the yarns produced shows that directing the fibres in the triangle zone could improve the yarn quality. The results indicate that the 75 degrees-biased grooved (from both sides towards the centre) rollers improve the yarn quality in terms of hairiness, elongation and imperfections.