Abstract:

In order to achieve better control over yarn tension during high speed warp knitting production, systematic experiments were carried out on HKS2-SE high speed warp knitting machine. Measuring the yarn tension under 1 000 r/min to 4 000 r/min, yarn tension levels were evaluated with the maximum, average and standard deviation. The dynamic tension curve, probability density curve, skewness and kurtosis of the single-cycle yarn were used to analyze the tension distribution and the fluctuation of the yarn tension. With the increase of machine speed, the maximum, average and standard deviation of yarn tension is found to decrease gradually, with the tension variation among the yarns becoming smaller and the overall yarn knitting tension declining. At the same time, it is witnessed that the height of the main wave peak of single cycle tension curve decreases with smaller fluctuation of yarn tension, while the fluctuation of yarn tension tends to increase when the machine speed is set too high or too low. When the machine speed is between 2 500 r/min and 3 500 r/min, the data distribution is closer to the average value of tension distribution curve, and the yarn tension become more stable.

Key words: high-speed warp knitting machine, yarn tension, probability density curve, tension distribution curve