Study On Spinning Process And Technology Of Efficient And Short Process Multi-Ends Spin PET POY

This paper is based on the WINGS POY spinning process of Barmag company in Germany, and the classic melt spinning theory is taken as a guide, also through studying and analysis the formation mechanism and difference of structure and properties about different wire cake at same spinning position. Finding out the main factors that cause differences, by improving the equipment and optimizing the process to reduce the difference of the structure and properties between wire cake at same spinning position, so as to improve the quality of product.About the spinning experiment, we obtain 277dtex/288f PET POY under the traditional ACW POY spinning process and the WINGS POY spinning process. The crystallinity, the sonic velocity of orientation factor, velocity modulus, boiling water shrinkage are tested and analyzed by DSC, the digital fiber sound velocimeter and so on. Through the research and analysis, we can find that:(1) At the same spinning position, the length of spinning path of two sides tows is longer than the tows middle of spinning position, the angle of external tow coated with wire guide hook is greater than the tow middle of spinning position, leading to the spinning tension and fluctuation of the tow at side of spinning position is larger than the tow middle of spinning position. There are differences of structure and properties between different rolls at same spinning position.(2) The orientation degree and the crystallinity of intermediate filament winding cake are lower than the external yam cake, but the crystal structure of intermediate filament winding cake is more even.(3) At the same spinning-bit, the yarn irregularity of external wire cake is higher than the middle filament roll. About different filament rolls winded by same winder and meantime, as the orientation degree and crystallinity of external filament winding cake is higher, but crystal structure of intermediate filament winding cake is more even. The breaking strength, elongation at break and boiling water shrinkage rate of intermediate filament cake are higher than the external wire cake, and the CV values of all three indicators of intermediate filament cake are lower than the external wire cake. The fluctuations of strength when being extended to 60% of elongation at break is a characterization that shows structural uniform of POY. The intermediate filament cake has lower fluctuation compared with the external wire cake cakes. That means the structure of the intermediate filament uniformity is better than the external wire cake.(4)Compared with the traditional ACW POY spinning process, the WINGS POY spinning system gathers the guide wire roller, network air nozzles and other components to the winding head, makes the spinning length significantly reduced, also reduce the disturbance caused by air flow inside the shop. The angle of tow coated with wire guide hook is reduced. That reduces the contact area of tow with the guide wire roller, and the impact of mechanical vibration. Making the filament rolls at the same spinning position has more even structure. The difference is less than the traditional ACW POY spinning process between different filament roll spun at coaxial winding. The mechanical properties are superior to the traditional process. Coefficient of variation of the experimental values of WINGS POY system are lower than the traditional ACW POY system. The quality of WINGS POY process product is superior to the traditional process.