Mechanical Insertion Reliability in Dense Plain Weave Wet Spun Linen Fabrics
Insertion reliability in dense wet spun linen depends on size film cohesion and precise unguided rapier trajectory to limit peak tension under 4.5 cN/tex.
Size Add-on Rate
Coating Quantity
Quantitative measurements define the weight of the protective starch or synthetic polymer film applied to warp yarns during the sizing process. The size add-on rate is expressed as a percentage of the dry weight of the yarn before it enters the sow box. It provides a baseline for ensuring the yarn can withstand the rigours of mechanical weaving.
Application Process
Control of the squeeze roller pressure and the concentration of the sizing bath determines how much liquid the flax fibres absorb. To calculate the size add-on rate accurately, the mill weighs a sample of the yarn before and after the treatment under controlled moisture conditions. Linen yarns often require a higher application than cotton because the fibre surface is smoother and more prone to abrasion.
High viscosity in the size mix can lead to an uneven coating that flakes off during weaving. It dictates the efficiency of the slashing department.
Weaving Benefit
Optimal film thickness prevents the breakage of individual filaments without making the yarn too brittle. When the size add-on rate is too low, the warp ends fray under the friction of the healds and the reed. Excessive sizing makes the yarn stiff and difficult to weave, leading to potential tension issues.
This metric is a primary indicator of weaving readiness.