Research On Combed Blended Process Of Polyester-cotton

Polyester-cotton blended yarn plays an important role in the field of taking fiber. In the traditional cotton-polyester blend process, the carding effect of polyester fiber is inadequate. Fiber arrangement is disorganized. More neps, thickness and thinness are produced in the process of drafting, which deteriorate the quality of the yarn. Combing equipment can obviously improve the fiber straight, parallel, separating degree, the fiber arrangement, the quality of yarn and fabric performance in the spinning process. Therefore, the combing machine is used to develop the polyestercotton combed blended technical route, which is the best way to improve the quality of blended yarn, enhance product competitiveness, expand product market.From the view of fiber movement, using the theory of fiber transmission and the generating mechanism of moving deviation to analyze the influence of fiber straight degree, parallel degree, separating degree on the yarn quality. Polyester-cotton combed blended technical route is innovated. The route made cotton and polyester fiber into the cotton lap and the polyester lap. The different quantities and weight of cotton and polyester lap are produced on the combing machine according to the cotton-polyester blend ratio. Polyester and cotton combed slivers are drafted and merged in the draft zone of the combing machine and the high quality polyestercotton combed yarn is obtained. On the basis of innovative combed blended technical route. The mathematical model of polyester-cotton lap mixed parameters is set up. The determining method of polyester and cotton fiber laps parameter and noil rate is raised according to the requirement of blended ratio. The problem of the polyester combing blended ratio difficul to control is solved. To "reduce noil rate, decrease the separation drafting force" as the goal, the relevant timing choices of polyester combed are analysed, the influence of fiber propertie and combing process parameters on the separation-drafting force are discussed, the optimal polyester combing process parameters are obtained and the problems of high noil rate, the difficulty of separation and the output fiber net broken down are solved. To "reduce cylinder combing force, eliminate neps and impurities, meet the requirement of fiber capacity" as the goal. The model of polyester combing cylinder’s teeth, needle tooth thickness and depth are established. The CAD and PRO/E are used to develop the special polyester combed cylinder and the problems of cylinder "applique", needle teeth and fiber damage in the polyester combed process are solved.The research results show that:(1) Polyester combing technology can obviously improve fiber alignment state in the fiber sliver, improve fiber straight, parallel, separating degree and polyester combed sliver and yarn quality. Compared with polyester carded yarn, the number of nep, thickness, thinness, 3 mm hairiness in the polyester combed yarn decreased significantly. When the separation gauge is 24.5 mm, nipping distance is 57.2 mm, the quality of polyester combed yarn is the best.(2) Using the Polyester-cotton combed blended technical route to spin the blended yarn when the cotton-polyester blend ratio are 65/50, 50/50, 35/65. Polyester-cotton combed blended ratio can effectively control within ±0.5%. Compared with polyester-cotton carded technical route, the maximum damping of nep content, 16 mm short-fiber ratio are 35%, 27.8% in the polyester-cotton combed sliver. Compared with polyester-cotton carded yarn, the maximum damping of nep, thickness, thinness, 3mm airiness are 32.6%, 26.8%, 50%, 13.66%, the maximum increase of breaking strength is 18.3% in the polyester-cotton combed yarn.