Twist optimization of polypropylene filament/aramid wrapped yarn

To evaluate the comprehensive quality of polypropylene filament /aramid wrapped yarn accurately and conveniently,five kinds of polypropylene filament / aramid wrapped yarns with different twists were produced successfully with the parallel spinning method by adjusting winding speed and spindle speed on ON-SC1000 fancy twisting machine. Seven indexes that would influence comprehensive quality of the wrapped yarns were tested,including the breaking elongation CV,the breaking strength CV,slug,knot,thin place,evenness and abrasion performance. It was found through calculation and the principal component analysis that the five kinds of wrapped yarn got the comprehensive score of 0. 067,- 0. 818,- 0. 751,- 1. 019,1. 476,respectively. Experiments demonstrat that the ranks of the yarns with different twists is 320,250,300,200,350 T / m,successively; and in the twist range from 250 T / m to 320 T / m,the wrapped yarns get excellent comprehensive performance which is beneficial to give full play to the excellent characteristics of the two kinds of filament.