Research On Double-Carding Rotor Spinning And Product Development

Since the 21st century,rotor spinning has developed rapidly,and the world’s total rotor spinning equipment has grown steadily.With the rapid development of economy in China,traditional rotor yarns are difficult to meet people’s needs,and the development of new varieties of rotor yarns is imminent.Conventional rotor-spinning technology encounters many difficulties because the combing roller is not very applicable for various fiber materials when facing to the versatility of the fiber material,which terribly restricts the development of the rotor spinning.In order to break through the bottleneck of the traditional rotor spinning technology,both domestic and foreign scholars have conducted the exploration of double-carding rotor spinning technology.Based on the previous research on double-carding rotor spinning technology,this paper further enriches the theory of double-carding rotor spinning and enriches the variety of rotor yarn products.The spinning experiments of various blended yarns were carried out on the improved double-carding rotor-spinning test machine and the traditional rotor-spinning test machine,leading to a comprehensive evaluation towards the performance of single and double-carding rotor yarns.And the technical advantages of double-carding rotor spinning will be verified.By studying the relationship between the carding roller and the yarn quality and the influence of the blending ratio and the feeding method on the fiber mixing effect,it provides a theoretical basis for the development of new varieties of rotor yarns.The research works are clarified below:Firstly,the equipment of the double-carding rotor spinning principle machine is improved,and the feeding and carding independent control is realized by adding the feeding roller shaft and the carding roller driving belt.Three kinds of blended yarns with different linear density and different blending ratios were spun on single and double-carding rotor-spinning testing machines,and the performance of yarns was comprehensively evaluated by fuzzy comprehensive evaluation de cisionmaking method.The results show that double-carding rotor spinning technology can effectively improve the quality of blended yarn.At the same time,the feeding position of the fiber strip has no significant influence on the yarn quality in the case where the specification and speed of the carding roller are constant.Secondly,research on the carding roller as one of the key equipments for rotor spinning.The effects of the size and speed of the carding roller on the yarn quality were investigated by a single factor test.The results show that the research theory of the carding roller in the traditional rotor spinning is still applicable to the double-carding rotor spinning.Depending on the type and performance of the fiber,choosing the appropriate size and speed of the carding roller will help improve the yarn quality.On the basis of the single factor test,the optimal combination of 35 tex polyester/cotton 65/35 rotor blended yarn was determined by orthogonal test,namely: left carding roller is OK37,right carding roller is OK40,the speed of the carding roller is 7000r/min,and the speed of the right carding roller is 7000r/min.Thirdly,study the effect of blending ratio and feeding method on fiber mixing effect.Taking the polyester/cotton blended yarn as an example,the mixing effect is characterized by the Hamilton index and the proportion of various types of fibers in different parts of the annulus.The results show that the appearance structure of the double-twisted rotor yarn is similar to that of the traditional rotor yarn,and there is no significant difference in the appearance of the polyester/cotton blended yarn with different blending ratios.The degree of internal and external transfer of the fiber is related to the blending ratio,and the smaller the proportion of the fiber,the preferential inward transfer.At the same time,the feeding method has an effect on the mixing of the fibers.Compared to conventional rotor spinning techniques,the mixing of the fibers in the rotor is uneven in the double-carding rotor spinning technique.Finally,based on the above research,the development of new yarn varieties.The appearance of the polyester/viscose yarn of the double-carding rotor spinning is longitudinally presented in a state of two colors,which are in a disorderly arrangement.The appearance effect is significantly different from that of the conventional rotor-spun spinning/kneading yarn.At the same time,the double-carding rotor spinning technology can develop three-component yarns with large differences in fiber properties.The spinning process parameters of 37 tex polyester/cotton/viscose 34/33/33 were optimized by the quadratic universal rotary combination design,and the optimal spinning process parameters were obtained: rotor speed 53787r/min,carding roller speed 6769r/min,design twist factor 416.Based on the development of three-component yarns,trial spinning of polyester/nylon/cotton/viscose 25/25/25/25 four-component yarns was carried out.The yarn development results show that the double-carding rotor spinning technology can be widely applied to the development of blended yarns and various mixed yarns with large differences in performance.