Metric Fibre Number Claims and the Test Method behind Them
Metric fibre number claims require ISO 2370 gravimetric verification because airflow instruments skew up to fifteen percent across retting types and moisture regains.
Wet Trough Temperature
Thermal Regulation
Heat transfer management during wet spinning dictates the internal cohesion of flax filaments emerging from the drawing baths. Wet trough temperature controls the viscosity of the pectin matrix surrounding elementary cells inside the fibre bundle. Operators maintain this thermal band within specific parameters to allow uniform drawing without snapping the delicate plant strands.
Lower thermal levels increase fluid resistance, which breaks the drafting rollers under excessive tension. Higher levels dissolve pectin too rapidly, leaving loose fibrils that clog subsequent combing combs.
Mill Standard
Internal process sheets record these bath readings alongside line speeds during every spinning shift. Quality control teams compare mill standards against buyer acceptance criteria before clearing spun yarn for weaving mills. Fabric grades depend on yarn evenness achieved during this spinning stage, whereas fibre grades measure raw flax harvested from fields.
Testing protocols require hourly checks of the immersion bath to prevent batch rejections at the finishing house.
Bath Threshold
Thermal deviations alter crystalline orientation inside the cellulose structure during the drawing phase. Mills adjust heating elements whenever ambient room conditions shift during seasonal changes. Proper bath heat ensures smooth passage through the drafting zone without generating excessive waste yarn on the bobbins.