Development of a mathematical model for weft yarn tension of an elastomeric weft insertion of rapier

The weft brake, a noxious event in weaving could often result in high tension peak values with a high risk of yarn breakage. Yarn tension is of paramount importance especially in the case of elastomeric weft yarn insertion as it can be stretched and recovered. Further, at any point of weft insertion, the elastomeric yarn tension of the weft shall not exceed its elastic limit to ensure complete recovery and avoid unexpected breakages. The greater acceptability of stretch fabrics is due to their exceptional qualities like higher extensibility, high degree of recovery, and extensive care. Core-spun yarns having elastane filament at the core and wrapped cotton fibers or polyesters are commonly used in the weaving process. To impart stretch ability to the yarns, elastic fibers like lycra /spandex are incorporated in them. In literature, there is a fundamental lack of a complete mathematical model related to weft yarn insertion processes. A mathematical model was developed to bridge the long-standing technological gap in related to elastomeric weft insertion on a rapier loom. Tension devices along the entire yarn path across the tension head were used in the derivation of a mathematical model for static tension variation at the weft insertion on a rapier loom. The dynamic tension added to the static tension was also modeled for elastomeric weft insertion. The model was validated with practical results within 10% accuracy level. However, during the experimentation, rapier Loom was run at a constant speed of 250 picks/min and the variation of dynamic tension with loom speed is yet open for .