Flax Fibre Non Cellulosic Content and Retting Chemistry
Residual pectin levels below 1.5 percent dictate successful wet spinning of fine flax yarns above Nm 40 without elevated end breakage rates.
Sliver Drafting Cohesion
Fiber Friction
Bast fiber processing relies on inter-fiber friction to hold parallelized flax strands together during sliver attenuation before spinning. The sliver drafting cohesion quantifies the mechanical resistance encountered when drawing untwisted fiber bundles through drafting rollers on a roving frame. Spinning mills record this property during quality control testing to adjust roller gauge settings and draft ratios for wet-spun flax lines.
Mill laboratory reports log cohesion values alongside fiber length distribution to ensure predictable yarn evenness during fine flax spinning operations.
Roller Attenuation
Drafting forces during sliver attenuation depend directly on fiber surface roughness and moisture levels in treated flax slivers. When inter-fiber cohesion is insufficient, slivers slip irregularly between drafting rollers, producing thin places and periodic mass variations in the drawn strand. Excessive cohesion causes fiber bundle choking and roller wrapping, leading to machine stoppages and uneven draft delivery.
Mill technicians regulate sliver preparation by applying specialized fiber lubricants or adjusting humidity levels in the drafting zone, stabilizing drafting resistance across variable fiber batches.
Yarn Evenness
Consistent inter-fiber resistance during drafting prevents drafting waves and reduces mass variation in final wet-spun linen yarns. Inadequate drafting force stability directly increases yarn irregularity ratings, resulting in visible striping or weak spots in finished woven linen fabrics.