Research On Condensing Mechanism And Yarn Quality In Punched Apron Compact Spinning

Traditional ring spinning is the dominant method of spinning because of its ripe processing techniques and good quality. Until now, ring spinning is still the standard to evaluate the quality of yarn made by other spinning method while more and more types of spinning are showing up.Hairiness is one of the main factors that influence the quality of yarn. Ring spinning technique can not handle the problem of hairiness due to the existence of Twist Triangular Space. During the actual production, hairiness can be reduced by the way of singeing or some others. But only the length of hairiness can be reduced except the quantity of it. In order to solve the problem of hairiness, experts find a new way out- Compact Spinning. Compact spinning develop from the theory of traditional ring spinning. It succeeds in handling the difficulty of hairiness, and the quantity of hairiness is decreased greatly.At present, Punched Apron Compact Spinning of Zinser (Germany) is one of the four systems of compact spinning. It militate by adding a suit of punched apron and the fourth roller in the position of nipper jaws of front roller in the traditional ring spinning machine, and it can be used for the spinning of all the fiber materials that can be completed by the ring spinning machine. So it is now widely adopted. In fact, the studies of Punched Apron Compact Spinning system mainly focus on the influence of the experiment spinning processing to the structure and quality of yarn including the comparative experiment with other compact spinning system.In order to find out condensing mechanism and the structure and quality of yarn, the model of flow field in the compact district of Punched Apron Compact Spinning system is established, and the flow characteristic together with the motion trail of single fiber in the triaxial flow field of the compact district are simulated. In addition, the force situation of single fiber in the process of compacting is also analyzed. The details of study content and conclusion can be seen as follow:(1) Establish the hydrokinetics model of Punched Apron Compact Spinning system. Use Gambit to protract according to the actual size of Punched Apron Compact Spinning system, and then compartmentalize gridding of the sketch. After that, the gridding map of triaxial flow field district for simulating is gained.(2) Iteratively compute the data of triaxial flow field in the compact district. Use Fluent for the hydrokinetics iterative computation in the gridding map protracted by Gambit, and the parameters such as flow rate and intensity of pressure in the compact district can be got.(3) Simulate the motion trail of single fiber during the processing of compacting. Use Matlab for the difference treatment with the data of flow rate in the flow field. Programming for the simulation of flow rate and the compacting process of single fiber, and get the Matlab difference diagram of flow rate and the simulation diagram of motion trail of single fiber.(4) Analyze the forces of single fiber in the process of compacting. According to the theory of dynamics, the forces of single fiber in the process of compacting are analyzed.(5) Analyze the spinning performance of Punched Apron Compact Spinning system and compare it with Traditional ring spinning system. Spinning yarn in the Punched Apron Compact Spinning system and Traditional ring spinning system, and then evaluate their spinning performance respectively. At the same time, compare analysis is also operated.All in all, the compact theory and the spinning performance of Punched Apron Compact Spinning system have been profoundly analyzed in the study.