Abstract:

Aiming at the lack of evaluation method of dynamic tension of warp knitting yarn obtained by high frequency testing instrument, an index, i. e. , the probability density curve and kurtosis, skewness used to evaluate the overall fluctuation of warp knitting yarn tension was proposed. In order to test the feasibility of the index, warp yarn tension within 30 s under five different machine speeds were tested by high frequency testing instrument. The probability density curve and kurtosis and skewness were used to analyze the tension data. The research results show that the krutosis of warp yarn tension under five different machine speeds are smaller than 0, and the skewness are greater than 0. The kurtosis and skewness decline with the increase of machine speed. Combine with the probability density curve, the research results show that with machine speed increase, the fluctuation of yarn tension decrease, which means yarn tension is more balanced. The results verify the feasibility of this evaluation method because it’s consistent with the actual knitting situation.

Key words: warp knitting, yarn tension, evaluation method, high frequency test