Maximizing Yarn and Fabric Strength Through Variance of HVI Elongation

Abstract

As a new method for maximizing yarn and fabric strengths, an exploratory blending experiment is completed in a 4-week period by processing 2117 bales of three different cottons in a textile mill to produce 94.4 tex (6.3/1 Ne) open-end spun yarns, and weaving them into a denim fabric. Bale selection is done in such a way that the variance of single fiber breaking elongations can be minimized within a laydown of 29 bales as well as among the fibers to be found within an arbitrary cross section of the yam produced from the laydown. The study shows that the variance of the HVI breaking elongations obtained from the cotton bales is useful for maximizing the resulting yarn strengths, especially when they are combined with the Mantis® single fiber test results. In addition, a follow-up study analyzes the HVI data and matching physical test data obtained from a 2-year production period. In all, 121,200 bales (4180 laydowns) are tested for HVI bundle strength, elongation, micronaire, length, and other properties. As in the exploratory study, the cotton bales are processed into 94.4 tex open-end spun yams and an identical denim fabric. The final analysis shows that the between-bale variance of HVI bundle breaking elongations within a laydown is quite useful as a criterion for bale selection and yarn and fabric strength maximization. An enhanced method is also developed to make use of the HVI elongation data together with the Mantis single fiber tensile test results. The new procedure is even more effective at maximizing yarn and fabric strengths.