Structural Measurement
Mathematical representation of the frequency of different fiber lengths within a raw material sample or a yarn batch defines the spinability and uniformity of the lot. This dataset is the fiber length distribution, which can be expressed either by weight or by the number of individual fibers measured.
Spinning Performance
Short fiber content and mean fiber length derived from the overall measurement govern the limits of yarn thinness and the required drafting roller settings on the spinning frame. A highly variable fiber length distribution increases the number of yarn defects, such as thick and thin places, and leads to high yarn breakage rates during the winding process. In contrast, a narrow distribution allows the yarn manufacturer to produce fine, high-strength threads with minimal waste.
Proper roll settings ensure that shorter fibers are held securely during the drafting process, preventing yarn irregularities.
Sorting Equipment
Advanced high-volume instruments measure individual fibers using optical sensors or capacitance to generate a complete histogram of the specimen. This measured fiber length distribution is analyzed to extract key parameters like the span length and uniformity index.
Quality Standard
Wool and cotton contracts specify the minimum acceptable mean length and maximum short fiber percentages to protect the buyer from low-grade shipments. Spinning mills run these tests on every incoming bale to blend raw materials into a consistent mix.
