Mass Deficiency
Yarn evaluation equipment detects local reductions in cross-sectional mass relative to the average yarn linear density. The thin places per kilometer metric quantifies severe yarn narrowings, typically dropping fifty percent below mean yarn diameter, recorded across standard test lengths. Flax yarn buyers check this specification on mill test reports to assess the risk of warp breakage during high-speed warping and weaving.
Export contracts specify maximum allowable thin spot frequencies per thousand meters to guarantee structural yarn integrity in fine linen fabrics.
Sensor Evaluation
High-speed testing units monitor moving yarn strands using photoelectric or capacitive sensors to detect localized mass drops along the thread axis. In flax fiber processing, thin spots result from uneven drafting or localized fiber slippage during roving attenuation. These narrow zones represent structural weak points where tensile strength drops drastically below nominal yarn break thresholds.
Spinning mills adjust drafting roller pressure and maintain optimal humidity in wet spinning frames to eliminate drafting voids and maintain uniform strand cross-sections.
Tensile Failure
Frequent cross-sectional narrowings directly increase end break rates during high-speed warping and loom shed opening cycles. High thin spot counts cause costly production stoppages and create structural weak points in finished linen cloth.
