Fibre Morphology
Mechanical processing during hackling often leaves loose surface micro-fibrils protruding along the flax line, creating microscopic fuzz that disrupts the smooth passage of strands through high-speed wet spinning frames. These stray cellulose fragments catch on drafting rollers, causing sudden yarn breakage and uneven hairiness in the finished linen yarn. Wet spinning technicians monitor this hairiness index closely on the inspection floor to adjust drafting speeds before excessive lint accumulation causes downtime.
Drafting Friction
Accumulating fuzz on the metal pins of the gills increases inter-fibre drag, altering the tension profile across the drafting zone in ways that produce thick spots in the yarn. Spinners calculate this frictional resistance using standard tension meters positioned between the break draft and main draft cylinders. High friction demands immediate application of softening lubricants or a reduction in machine speed to prevent roving rupture.
Yarn Grading
Quality control inspectors evaluate yarn regularity on black boards under standardized lighting, checking for stray hairs that indicate poor hackling efficiency during preparation. Batches exceeding maximum hairiness limits fail export standards for high-end shirting and must be diverted to coarser industrial applications. Final acceptance depends strictly on these physical uniformity checks recorded in the lot certificate.
