11–an Alternative Approach to Two-Fold Weaving Yarn Part Ii: The Theoretical Model

The theoretical model underlying a two-strand spinning system is given. It is shown that, for an idealized model, the equilibrium twist in the strands is dependent upon a torsion balance existing between an individual strand above the convergence point and the strand as it lies in th plied structure. As a consequence, at equilibrium, twist in the strands relies solely on ply-twist and the helix radius of the strands in the ply. Basic equations are derived that lead to a method of evaluating trapped strand-twist in the resultant yarn that is produced by changes in twist in the strands when equilibrium is deliberately perturbed.