Prediction of Selected Properties of Cotton Type Rotor Yarns

Yarn mechanical and geometrical properties are dependent on the cotton fibres quality and technology of yarn production. The main aim of this paper is description of the influence of cotton fibre properties characterizing their quality on rotor yarn selected properties. There are several factors influencing quality of cotton fibres and variability of parameters is relatively high in terms of cotton cultivars. There are many inter dependencies between cotton parameters leading to the strong multicollinearities. Therefore the complex quality criterion is used together with fibre parameters in investigation of their influence on the yarn properties. The degree of cotton fibres quality is determined by using complex criterion (utility value). The basic construction parameters of yarns are yarn count “Jem” and yarn twist characterized e.g. by Phrix twist coefficient “alf”. From these parameters the structural characteristics as packing density, orientation and mean surface helix angle can be computed. Total numbers of 180 cotton rotor yarns were prepared from seventeen kinds of cottons in five levels of yarn count and two levels of Phrix twist coefficient. For prediction of the yarn strength and mass unevenness from fibre quality and yarn structural parameters the dimension reduction approach combined with linear regression is used. The prediction ability is characterized by cross validation techniques.