This paper presents a mechanical model in which dynamic equilibriums of forces and moments are considered. This model is able to quantitatively describe twist distribution in the frictional contact zone inside a rotor in terms of yam, machine, and operational parameters. Four cases of the application of this model are discussed. Three terms—the deviate angle, yarn tension, and yarn twist blockage—are given as functions of the wrap angle, contact surface factor, torsional factor, and rotary speed factor.
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