Nep Level as an Index of the Structural Inhomogeneity of Air-Jet Textured Yarn

Abstract

Results are reported for experiments conducted to correlate different structural in homogeneity parameters of air-jet textured yams, such as number of neps per thousand meters, number of thick places per thousand meters, CV% of yam linear density, CV% of yam strength, and CV% of loop frequency. All these parameters are highly correlated, and so the various indices of structural inhomogeneity can be represented by only one of them. Number of neps per thousand meters has been suggested as the index of structural inhomogeneity of air-jet textured yarns due to its quick and easy assessment, high degree of sensitivity to changes in raw material and process parameters, and very high correlation with other parameters.

Formation of Neps in Air-Jet Texturing Using a Central Composite Design

“…Nep formation in air-jet texturing, which affects the quality of the textured yarn, is influenced by variations in parameters such as raw materials and process and machine variables [ 4,6 ] . Increasing some of these variables results in higher nep formation, while increasing other variables causes fewer neps.…”