Spin-Draw (One-Step) FDY Process
topic
One-step spin-draw combines melt spinning and drawing in a single machine: melt extruded at 280–290°C → quench → first godet (1000–1500 m/min) → heater (80–90°C) → second godet (5000–6000 m/min, draw zone) → third godet (relax, +relaxation 3–5%) → winder. Produces fully drawn flat yarn (FDY) with BWS <2%, elongation 20–35%, tenacity 3.5–4.5 cN/dtex. Eliminates POY storage and separate draw-texturing.
Role
Spin-draw FDY is the dominant process for producing flat woven fabric yarns. Understanding its integrated process control — particularly the draw zone and heat-setting godet — is essential for polyester process engineering.