Determining Flax Staple Profile Using Manual Comb Sorting
Manual comb sorting by ISO 2370 isolates technical flax bundle length profiles to prevent drafting waves, control short fibre content, and enforce purchase contracts.
Modal Length Interval
Distribution Parameter
Fibre arrays in textile manufacturing rarely display a uniform distribution, making the identification of the most common length category essential for process control. For linen spinners, the modal length interval represents the specific range of fibre lengths that occurs with the highest frequency within a given sample. This value tells the yarn designer which fibre length dominates the mixture, providing a clearer picture of the raw material than a simple average.
Analytical Procedure
Technicians isolate this band by plotting the frequency distribution of fibre lengths from a comb sorter analysis. The modal length interval is represented by the tallest column on the resulting histogram. Knowing this value allows for precise optimization of yarn spinning limits.
It represents the actual physical behavior of the majority of the fibre population during draft.
Production Impact
Woven fabric strength depends on yarn uniformity, which is heavily influenced by how closely the fibres group around this dominant length. When the modal length interval is narrow, the drafting rollers can be set to work with high efficiency, leading to a highly uniform sliver. A wide or fragmented distribution forces the mill to use slower processing speeds and leads to more yarn hairiness.
This parameter is monitored continuously in high-throughput Chinese mills to ensure that incoming shipments of flax match the technical specifications required for their high-speed looms.