Simulation of sliver blending and evaluation of blending irregularity

Abstract

The quality of blended yarn depends on the uniformity of the blending of the multi-component fibers in the yarn, and sliver blending is a process necessary for mixing fibers. The movement of fibers directly affects the distribution and mixing of fibers in the sliver. In this paper, the sliver blending process was simulated, and a method for the evaluation of sliver blending irregularity was proposed. The effects of passages of drawing and blending ratio on the sliver mixing uniformity were studied and verified both by experiment and simulation. The results show that the blending irregularity decreases gradually and tends to be stable with the increase of the passages of blending drawing. The more similar the blending ratio of the two components with approximately equal linear densities, the easier it is for the component fibers to mix evenly in the sliver. The simulation results are in good agreement with the measured values and previous research results. In addition, the blending irregularity of fiber components in the blended sliver can be predicted by the simulation method.

Application of image processing technology on testing blending ratio and blending irregularity of blended yarns

“…According to the division method of blended sliver in the previous study, 15,16 the center of gravity of the yarn/sliver cross section was taken as the center, and the maximum radius was the radius of the yarn/sliver, then the cross section was divided into 60 fan-rings consisting of 10 fans and six rings, as shown in Figure 11. The center of gravity coordinate is where, sumX is the sum of X coordinates of the pixels in the image of the target image, and sumY is the sum of Y coordinates.…”

“…According to the test method of blending irregularity proposed in our previous study, 15,16 the yarn/sliver was divided as shown in Figure 3, and the blending ratio of each component fiber in each fan-ring was measured respectively. As mentioned in previous studies, 15,16 the blending irregularity of smallest component was used to express the blending irregularity of the blended yarn. Substituting the ratio of blending within each fan-ring of the smallest components into formula (1), the blending irregularity C can be calculated.…”

“…In our previous study, 15,16 the multiple cross section image of blended yarn was divided into fan-rings with equal area, the blending uniformity or irregularity both in cross section (including radial and circumferential direction) and in longitudinal section of the blended yarns can be calculated. Thus, this method can be used to evaluate the blending irregularity more comprehensively.…”