Cotton Fiber Length Distribution Metrics and Carded Yarn Quality
AFIS short fiber content by weight in raw cotton must remain below 8.5 percent to prevent severe mass variance and tenacity drop in carded yarn spinning.
Card Sliver Uniformity
Output Consistency
An operational metric assesses the variation in linear density along a continuous strand of untwisted cotton fibers produced by a carding machine. Mill technicians track card sliver uniformity to verify that the carding teeth are distributing fibers evenly. This evaluation does not measure individual fiber strength.
Mechanical Verification
Mechanical defects like worn clothing or incorrect cylinder speeds cause periodic mass variations in the output strand. Regular measurement of card sliver uniformity detects these anomalies before the sliver reaches the drawframe. Proper maintenance prevents downstream drafting errors.
Process Optimization
Drafting operations require highly consistent input strands to prevent the formation of thick and thin regions in subsequent drawing and spinning stages. If card sliver uniformity remains poor, the drawframe cannot correct the rapid mass fluctuations that later appear as yarn defects. Thus, maintaining low sliver variability acts as a prerequisite for high-speed yarn production.
Inspection Protocol
Continuous capacitive testing on the production floor provides real-time deviation coefficients to guide operator intervention. Mill standards for card sliver uniformity dictate a maximum allowable coefficient of variation of three and a half percent. When this threshold is exceeded, the operator halts the carding machine to inspect the take-off rolls and coiler mechanism.