Translating Metric Fibre Number into Wet Spun Line Yarn Limits
Metric fibre number defines wet-spun line yarn limits by establishing the minimum cross-sectional elementary fibre count required to sustain drafting tension.
Gravimetric Fineness Sorting
Fibre Measurement
The classification of raw flax stems relies on the precise determination of mass per unit of length to predict spinning performance. Gravimetric fineness sorting operates during the initial scutching stage by measuring the linear density of individual fibre bundles to establish consistent batch quality. Technicians weigh set lengths of cleaned fibre against a precision balance to calculate the specific mass in tex or millitex.
Batches failing the established weight thresholds are diverted to secondary processing lines to prevent uneven draw frames during the subsequent carding operation. Consistent mass distribution determines the final strength of the yarn and its suitability for high speed textile machinery.
Sorting Mechanics
Mechanical vibration tables facilitate the physical separation of material based on the downward force exerted by specific bundles as they traverse a calibrated airflow. Dense clusters fall into collecting hoppers while lighter material continues toward the suction inlets for further refinement. Automated sensors record the frequency and mass of the deposits as the flax moves across the perforated deck.
Internal logic controllers cross reference these weight values with the expected moisture content of the incoming batch to ensure the accuracy of the final classification remains stable. Divergent air pressure settings allow for the creation of specific thickness grades that match the requirements of high quality weaving looms. Mills maintain these settings in a digital ledger to ensure every tonne of product meets the requirements defined in the export contract.
Quality Protocol
Standardisation at this stage requires the separation of fibre grade classifications from the final fabric specifications used by the downstream buyer. A mill enforces internal thresholds for mass uniformity to reduce waste during the spinning process whereas the buyer defines acceptance criteria based on the appearance of the finished cloth. Discrepancies between the mill output and the buyer expectation trigger a formal inspection of the baled inventory to identify potential variability in the sorting equipment.
Each bale carries a tracking code that correlates the fibre weight distribution directly to the raw material supplier. Accurate sorting reduces the frequency of thread breakage on automatic looms and lowers the volume of factory reject material.