Evaluating Dynamic Friction Limits in Fine Wet Spun Linen Warps under Varying Humidity
Fine wet spun linen warps perform best between 68 and 72 percent relative humidity, capping dynamic friction below 0.35 to prevent warp tension breaks.
Lea Metric Count
Spinning Density
Flax yarn evaluation relies on the lea metric count to establish linear mass density during the drafting phase in Chinese wet spinning mills. The metric measures the length of yarn contained in a specific mass unit, expressed as the number of leas per pound. A standard lea contains one hundred and twenty yards, and the numerical value rises as the yarn grows finer.
Production lines calculate this density on conditioned skeins after moisture equilibrium occurs in a controlled testing room. Quality controllers record the results on the mill production ledger alongside twist coefficients and breaking tenacity values.
Yarn Classification
Commercial transactions distinguish between raw fibre grades and finished yarn specifications before export documents clear customs. Fibre grades depend on length, fineness and extraneous matter content measured on the bale floor before carding begins. Yarn grades derive entirely from the metric count and hairiness measurements recorded after ring spinning and steaming operations.
Mills maintain internal standards for operational control that often exceed the minimum thresholds demanded by overseas buyers. Buyers apply strict tolerance bands to the metric count to ensure uniform warp tension during subsequent weaving on automated looms.
Tolerance Limits
Export contracts establish strict acceptance criteria for mass variations across consecutive yarn deliveries from the spinning mill. Mill laboratories test conditioned packages to verify that actual counts remain within three percent of the nominal target stated on the commercial invoice. Variations exceeding this threshold trigger financial penalties or rejection of the entire lot by the finishing house.
Weaving sheds depend on consistent metric counts to prevent warp breakage during high speed sizing and shedding cycles. Automated tension monitors verify linear density continuously as yarn transfers from bobbin to beam prior to loom entry.