自捻纱纺纱速度对自捻捻度的影响

Effect of producing speed on self-twist in self-twist spinning system

自捻纱由交替的Z捻段和S捻段以及无捻区段3个区段组成。对比观察自捻纱和相同支数环锭单纱和股线的纵截面,结果显示:自捻纱Z捻段和S捻段的纵截面特征和环锭股线近似。自捻纱的无捻区由分离的2根须条组成,是影响纱线性能的关键区段。纺制2种纺纱线密度,5种纺纱速度自捻纱,测量其Z捻段和S捻段自捻捻度及无捻区长度,结果表明:自捻纱的Z捻段和S捻段的自捻捻度随纺纱速度增加而下降。在周期长度和自捻罗拉往复动程固定的前提下,自捻捻度不仅和纺纱线密度有关,还与纺纱速度有关。自捻纱无捻区长度随着纺纱速度的增加而增加。纺纱线密度越低,无捻区长度越大。

Self-twist yarn consists of three zones： Z-twist zone,S-twist zone and no twist zone.By comparison longitudinal shape of self-twist yarn with single yarn and two-plied yarn in ring spinning,the results show Z-twist zone and S-twist zone of self-twist yarn have the likewise characteristic with two-plied yarn in ring spinning.No twist zone of self-twist yarn is composed of two separated strands,which is the critical zone influencing the yarn performance.Two linear density self-twist acrylic yarns are spun with five different producing speed.By testing Z-twists,S-twists and no twist length,the results show that Z-twists and S-twists per half cycle of self-twist yarn decrease with the increase of self-twist producing speed.Therefore,in a fixed cycle length and oscillating stroke of self-twist rollers,self-twist numbers per half cycle are not only relative with the self-twist yarn counts,but also the producing speed.The magnitude of no twist zone length has increased with the increase of producing speed and is relative with the yarn count.The coarser the yarn count,the greater no twist length.