Roller Eccentricity and Wear
topic
Bottom rollers are fluted steel cylinders with typical eccentricity tolerance of ±0.02 mm; wear increases eccentricity to 0.05–0.15 mm, generating periodic drafting faults. Top roller bearing wear causes similar effects. Eccentricity is measured with dial gauges during maintenance. Roller reconditioning (re-fluting, re-grinding) restores geometry. Flute profile (straight, helical, knurled) affects grip characteristics for different fibre types.
Role
Roller condition monitoring is a preventive quality management discipline. Undetected roller eccentricity is the leading cause of periodic yarn faults in established mills, as it develops gradually and is invisible without systematic measurement. Building a roller maintenance schedule around eccentricity thresholds prevents catastrophic quality failures and customer complaints.