气流纱的拉伸特性研究

本文讨论气流纱的拉伸特性。Hearle曾对具有理想结构纱线的拉伸特性进行过比较完整的研究工作。本文则根据气流纱独特的成纱结构,对Hearle理论在气流纱中的应用作了一定的修正,并在此基础上对气流纱的拉伸特性作了分析计算。计算结果与实测结果基本相符。最后还从气流纱的应力-应变关系式中,就影响气流纱强力、初始模量以及断裂功等等力学特性的一些主要工艺参数进行了分析讨论。得出合理选用阻捻盘、很好控制捻度传递长度;合理设计与选用分梳及输棉机构,在不断改善单纤维供应的同时,尽量减少纤维损伤,提高纤维有效长度;适当提高纺纱张力,增加纤维转移等等都是改善气流纱强力等力学特性、提高成纱质量的有效途径。对工业用气流纱,还可通过合理设计凝棉槽,以提高气流纱紧密度的途径来提高气流纱强力。

TENSILE BEHAVIOUR OF ROTOR SPUN YARNS

This paper deals with the tensile behaviour of rotor spun yarns. Hearle has made valuable contributions to the tensile behaviour of staple-fiber yarn, his work, nowever, majorly covered ring spun yarn which is considered to have ideal construction. Having regard to the special construction of rotor spun yarn, some improvements on Hearle's theory have been made in order to apply Hearle's theory to rotor spun yarn. Based on these improvements the tensile curve of rotor spun yarn has been calculated and the result was satisfactory. The paper then goes into investigating the effect of main machine parameters and spinning conditions, such as P.T.E. length, fiber effective length, yarn specific volume and fiber migration ratio, on the tensile behaviour of rotor spun yarn. It was found that the following are noteworthy for improving the mechanical properties of rotor spun yarn: 1. Selecting suitable navel so as to control the P.T.E. length within a reasonable range. 2. Improving the design of single fiber supply device to decrease the amount of spoiled fiber and hence increase the fiber effective length. 3. Increasing spinning yarn tension without yarn break to enhance the fiber migration ratio. 4. For the rotor in yarn of industrial use, it is the way to increase the yarn strength that the rotor groove should be designed with the groove angle that is of benefit to decrease the yarn specific volume.