Twist Liveliness and Snarling
topic
Twist liveliness is the tendency of a single yarn to untwist and re-twist (snarl) when tension is removed, caused by stored torsional energy from twisting. Measured by the snarling test: yarn loop contracts to a tight snarl under zero tension. Liveliness increases with TM and decreases with heat setting, steaming, or folding. Highly lively singles yarns cause: weaving tension variation, knitting loop distortion, and stitching problems in sewing.
Role
Twist liveliness is a process engineering problem that is often overlooked in spinning quality control but creates significant problems in downstream processing. Understanding liveliness measurement and control methods — yarn steaming (autoclave treatment at 80–100°C steam for 30 min) to set twist — is essential knowledge for yarn production engineers supplying hosiery, knitting, and sewing thread markets.