In this research. the weft twist loss across the width of the fabric at air-jet weaving machine have been studied. The phenomena has been investigated considering the effect of the following parameters :
- Speed of weaving machine (X1),(635, 755 ) p/min , for Ne 20 and Ne 30
and (605, 740) p/min , for Ne 40.
- Measuring position across the fabric width (X2): two positions .
-Yarn twist multiplier ( 3 ) :(3.4, 3.8, 4.2) .
- Main nozzle pressure (X4 ): (4, 4.5, 5) bar, for Ne 20 and( 2.5, 3,3.5)
bar, for Ne (30, 40).
The phenomena of the twist loss is analyzed experimentally and theoretically . Also the variance analysis technique was used to find the main and interaction effects of the parameters on the weft twist loss and the corresponding weft strength .
The results indicated that the weft twist loss is concentrated at the leading end of the weft, with very little twist gain at the rear end ( picking side). Also the weft twist was affected significantly by measuring position and twist multiplier .In terms of two factor interactions, the result show : machine speed by twist multiplier ( X1 X3 ), twist multiplier by pressure (X3 X4) and machine speed by measuring position (X1 X2 ) affect significantly on the weft twist loss.