A Study of the Theory of Drafting Force in a Roller-Drafting Process

Abstract

An analysis was made of the pressure distribution inside a tensioned, twisted fiber assembly. As a result of this analysis, three different expressions for the pressure, each resulting in the same average value for low twists, are obtained. Any of these expressions can be used to calculate the drafting force of a relatively low-twisted fiber assembly such as a roving or the strength of a low-twist staple-fiber yarn. In this paper, the drafting force and other associated problems have been dealt with theoretically, which can be very useful in understanding the dynamics of a roller-drafting process.

Keywords

Roving yam fiber assembly. Fiber migration. Roller drafting. Axial tension yarn stress fiber stress twist fiber length length-biased frequency distribution draft twist angle. Transverse pressure distribution drafting force strength fiber strain yarn strain yarn modulus. Drafting-force theory. Theoretical analysis constant-tension model variable-tension model Grosberg-Smith' model.

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