Experimental study on the spinning geometry of multi-thread fancy yarn on hollow-spindle spinning machines: Part I

Purpose The purpose of this paper is to define the relationships between the first spinning zone of the hollow-spindle spinning system and technological parameters of manufacturing multi-thread fancy yarn. Design/methodology/approach A simple mathematical equation was introduced to account for the effect-thread helices. The validity of this equation was tested using visual observations of the helices of the effect thread in terms of their number, width and regularity and then compared against the theoretical values. Findings It was found that higher overfeed ratios increased the diameter of the helices without affecting their number, while increasing the rotational speed increased their number but reduced their diameter. The effect of these changes on the fancy yarns was that higher number of helices resulted in more fancy profiles while wider helices resulted in larger fancy profiles. Originality/value This research offers fancy yarn manufacturers a better understanding of the manufacturing process of fancy yarn and its practical advantage is to help them in determining the type of the resultant fancy yarns by controlling the geometry of the first spinning zone.