Determining Raw Cashmere Micron Profiles and Dehairing Yields
Determining raw cashmere value requires combined OFDA micron profiling and oven-dry yield mass balance testing to calculate true clean dehaired cost.
Hauteur
Length Distribution
Statistical indicator that represents the average fibre length in a combed wool top as measured by frequency rather than mass dictates how the spinning machines are calibrated for yarn production. When yarn technicians refer to hauteur, they are focusing on the numerical average that treats every strand equally regardless of its weight or thickness. This metric differs from the barbe which focuses on mass distribution inside the sliver.
It allows the mill to predict how many fibres will be gripped simultaneously by the drawing rollers at any given distance. Accurate hauteur data helps maintain the correct draft ratio so the resulting yarn has high consistency and few thick sections. It serves as the commercial standard for specifying wool lots in several global trading regions.
Sliver Calibration
Measuring hauteur involves pulling a representative sample from the top and aligning all the fibres at a single base line before measuring their individual lengths. This calculation results in a lower value than the barbe because the many short fibres in the sample pull the simple average downward more significantly than they do in a mass-weighted measurement. Because spinning frames respond to the actual number of fibre ends in the drafting zone, this measure provides the physical data needed to prevent sliver slippage.
Technicians adjust the tension settings on the high speed frames according to the specific hauteur of the input material. If the input fluctuates, the machine must be recalibrated to avoid producing yarn with low tensile strength or excessive hairiness. Consistent hauteur results across several wool deliveries indicate that the combing facility is maintaining stable operational quality.
Fibre Inspection
Verification of fibre length happens in the mill laboratory using automated comb sorters or optical systems that count the strands as they pass through a laser field. Hauteur values are listed on every commercial wool top certificate and form a key part of the price negotiation between the buyer and the seller. If a test results in a height lower than the specified requirement, it suggests that excessive fibre breakage occurred during the previous combing stages.
Low values indicate a weaker spinning performance and a higher risk of defects in the final woven or knitted pieces. Spinners use the hauteur to decide if a wool batch is suitable for their finest counts or if it must be downgraded to coarser yarn sizes. This value guides the overall strategy for inventory management and batch blending inside the factory.
Production Consistency
Ensuring a stable hauteur throughout a massive order requires careful selection of raw wool lots and consistent maintenance of the carding and combing equipment. High variations in this length metric lead to unpredictable yarn results and increased downtime in the winding room. Success in wool processing depends on maintaining the specific distance between the mean fibre length and the distribution spread.
The hauteur provides the essential coordinate for locating where the majority of individual fibre ends sit within the sliver. Modern textile production relies on these precise geometric facts to maintain speeds exceeding several hundred metres per minute. Understanding these nuances between weighted and simple averages is fundamental to modern wool craft.