Instrument Specification
A laboratory tool organizes individual flax fibers by their specific lengths using a sequence of metal combs. Utilizing a johannsen sorter allows a mill to create a visual and mathematical profile of the fiber distribution in a raw sample. This mapping helps predict the spinnability of a lot and the eventual strength of the finished linen yarn.
It is essential for selecting the correct gear ratios and draft settings on the production line to minimize material waste.
Diagnostic Operation
Operating the johannsen sorter involves manually transferring small tufts of fiber across the graduated rows of teeth to isolate various length fractions. Once sorted, the technician collects each group and weighs them separately to determine the percentage of short, medium and long fibers. These results generate a fiber length histogram that reveals any inconsistency in the hackling process.
If the johannsen sorter shows a high percentage of short fibers, the mill redirects the lot away from high grade yarn production to avoid breakage.
Comparative Grading
Mills use data from the johannsen sorter to group lots into standardized categories for consistent batch processing. Large variations between arrivals suggest issues at the retting or scutching plants. Maintaining regular sorting checks prevents low quality inclusions from polluting premium spinning runs.
