The Research In Air-Jet Vortex Spinning

Air-jet vortex spinning is a new kind of spinning method developed from air-jet spinning, which utilizes high-speed airflow produced by nozzles to finish twisting and wrapping. Its advantage has made more and more people's attention since Murata Vortex Spinner was exhibited. This spinning method utilizes high-speed air-flow to separate the fibers, which make these fibers have better state of straight and more parallel than air-jet spinning, so the yarn strength can be improved more easily.In this paper, the design of this nozzle device is described in detail, the parameters of the nozzle and their function are analyzed. Then the mechanism of air-jet vortex spinning is explained. In order to make the mechanism be understood easily, the characters of the vortex field are introduced, then the movement of the fibers in the nozzle is analyzed. In addition, on the basis of high speed photographs, the movement of the fibers is observed and the mechanism is explained advantageously, at last we give the conclusion that this spinning method is incomplete open-end spinning.In order to improve the nozzle structure, many experiments aredesigned to study the relationship between the structure parameters^ technologic parameters and yam quality, especially the yam strength. Some structure parameters, such as: screw angle, the length of needle, the angle of air hole, the location of the air hole, spinning speed, nozzle pressure, the length from the front roller to the nozzle, are optimized by single factor and combination experiments. Their effects to the yam strength are analyzed.At last, yarn structure and performance are tested and analyzed. Some colored fibers are blended in the roving and then the fibers' arrangement can be observed by tracing fibers. The surface arrangement of the yam can be observed under the microscope. Comparing the performance among air-jet vortex yarn, ring yarn and air-jet yarn, it can be found that the strength of air-jet vortex yarn is much higher than that of air-jet yam but lower than that of ring yam, and the air-jet vortex yarn has the least hairiness.Li Yongxia Supervised by Yu Chongwen...