Quantitative Impact of Short Fiber Content on Combed Cotton Rotor Yarn Tenacity Limits
Combing cotton sliver below 5.5% short fiber content raises rotor yarn tenacity ceilings to 18.5 cN/tex by reducing friction slip inside the rotor groove.
Twist Factor Alpha
Twist Geometry
Geometric coefficient used to describe the relationship between yarn count and the amount of twist per unit length determines the spiral angle of the fibers. Spinners adjust this value to control the hardness and strength of the yarn. The specific twist factor alpha is chosen based on whether the material is intended for knitting or fabric construction.
Angle Calculation
Mathematical formula relates the turns per inch to the square root of the yarn count to ensure consistent properties across different thicknesses. This calculation allows a mill to maintain the same fiber inclination angle regardless of the final yarn size. A constant twist factor alpha results in a similar handle and appearance for a range of counts within a product line.
Handle Strength
Mechanical characteristics of the yarn, such as its resistance to pilling and its stiffness, are tied to this coefficient. Higher values produce a hard, strong yarn that is suitable for durable workwear or gabardine. Lower values result in a softer, bulkier yarn that is preferred for hosiery and delicate knitwear.
Count Variation
Operational limits for twist are restricted by the fiber length and the required spinning speed. If the factor is set too high, the yarn becomes over-twisted and may snarl or kink during processing. Mill technicians must verify the twist factor alpha during the setup of the ring frame to ensure the yarn meets the physical requirements of the customer.