Yarn Friction and Abrasion Testing
category
Yarn friction and abrasion testing characterises the resistance of yarns to surface wear and the frictional forces generated during yarn-to-metal (loom heddles, reed, guides) and yarn-to-yarn contact during processing — properties determining warp breakage rate in weaving, needle damage in knitting, and yarn guide wear in high-speed winding. Yarn-to-metal friction coefficient (capstan method, ASTM D3108: yarn wrapped 180° around polished steel pin at 200–1,000 m/min, tension ratio T₂/T₁ measured → µ = ln(T₂/T₁) / π): cotton ring yarn µ = 0.18–0.25 on steel at 200 m/min, reducing to 0.12–0.18 at 1,000 m/min (hydrodynamic lubrication regime); polyester flat yarn µ = 0.20–0.35 (higher than cotton, causes more reed wear); Dyneema UHMWPE µ = 0.06–0.10 (very low friction, good for wire replacement in standing ropes). Yarn abrasion resistance (Zweigle abrasion tester, Taber abraser adapted for yarn: yarn wrapped under 50 cN tension over abrasive surface CS-10 wheel, cycles to 50% strength loss — 800–2,000 cycles for cotton weaving yarn, > 5,000 cycles for carpet yarn). Weavability test (Cusick drape test adapted, yarn guide abrasion cycle test — yarn cycled over steel wire guide 50,000 times at 50 cN tension: mass loss <2 mg/100m and no filament breakage = acceptable weaving quality). Knitting yarn friction (SDL Atlas Friction Tester, yarn-to-yarn friction under simulated knitting needle contact, 45° wrap angle, 10 cm/min speed — µ < 0.3 for standard knitting, µ < 0.2 for high-speed warp knitting at 3,000 course/min).
Role
Yarn friction and abrasion testing predicts processability in weaving and knitting machinery — yarn-to-metal friction coefficient directly determines warp tension uniformity across shed width, reed wear rate, and heddle eye damage frequency, while abrasion resistance determines whether yarn survives the 5,000–50,000 loom shed formation cycles per hour without surface damage that causes increased warp breakage and fabric defects.