Using the mechanism of collecting and doubling in rotor spinning, the parameters of rotor spun slub yam are analyzed with special reference to slub length, factors affecting slub length, and the inherent connection of slub length to slub amplitude. The results show that slub length increases with an increasing slub multiple: the slub length is always longer than the rotor's circumferential length, and the factors affecting the slub length are rotor diameter, normal yam count, slub multiple, and servomotor performance.
