Prediction of spun
Prediction of spun yarn strength at different gauge lengths
using Weibull distribution
R S Rengasamy, S M Ishtiaque & Anindya Ghosh
Received 14 September 2004; accepted 11 November 2004
An attempt has been made for strength forecasting of different spun yarns at any gauge length from the knowledge of strength distribution at a given gauge length as well as the weakest-link scaling theorem. The shape and scale parameters of Weibull distribution have been determined. Yarns produced on each of the four major spinning systems (ring, rotor, air-jet and friction) have been tested for tenacity at a wide range of gauge lengths (0-500 mm). From the Weibull distribution parameters at 10, 50 and 500 mm gauge lengths and by using weakest-link scaling, the tenacity of yarns at other gauge lengths has been calculated. Then the results of theoretical model for yarn strength have been compared with the experimental results. It is observed that the data of yarn tenacity are well fit to two-parameter Weibull distribution. The Weibull shape parameter diminishes as the gauge length decreases. None of the yarns strictly follows the classical weakest-link theory and there is a considerable change in failure mechanism for all the yarns as the gauge length is varied.
Keywords: Gauge length, Scale parameter, Shape parameter, Spinning, Viscose fibre, Weibull distribution, Yarn tenacity
IPC Code: Int. Cl.7 D02G3/00