Foreign Material
Accidental introduction of non-lint materials into the fiber stream during mechanical separation creates permanent defects in the raw material. Cotton ginning contamination occurs when plastic baling twine, rubber parts, or machine grease become mixed with the harvested fiber. These materials are difficult to remove once they are compressed into the bale.
Their presence lowers the commercial grade and value of the crop.
Processing Hazard
Spinning mills experience frequent yarn breakages and fabric defects when processing contaminated fiber blocks. Plastic film shreds into tiny fragments during the carding and drawing processes. These fragments do not absorb dyes, leaving white specks in the finished, dyed fabric.
Large pieces of grease or rubber can also damage spinning machinery.
Detection Routine
Automated optical sorters in the ginning and blowroom lines scan the fiber flow to detect and eject foreign matter. High-speed cameras identify non-cotton elements by their color and texture differences. High-velocity air jets then blast the contaminant from the fiber stream.
Despite these systems, some small particles escape detection.
Prevention Protocol
Manual inspection before ginning remains the most reliable primary defense. Workers remove visible plastics and non-lint materials from the seed cotton. This step prevents the foreign material from being shredded by the gin saws.
