Viscoelastic Stress Relaxation Profiles in Heat Set Polyurethane Stretch Wovens
Controlled stenter dwell at 185-195°C stabilizes polyurethane hard segments to minimize viscoelastic force decay and garment bagging in stretch wovens.
Cross Machine Pin Tension
Lateral Force
Transverse pulling force represents the critical lateral resistance established during stenter drying and heat setting of open-width fabrics. Adjusting the cross machine pin tension determines the finished width and weight of the textile. Mill operators configure this parameter to counteract the natural warp-wise pull as fabric travels through the heating chambers.
Incorrect balance causes bow or skew defects in the finished shipment.
Process Control
Mechanical adjustments on the stenter frame control the lateral extension of the fabric by moving the pin rails further apart or closer together. This tension must be calibrated for each fabric type to avoid over-stretching the weft threads or causing the selvage to slip off the pins. Precision controllers monitor the pressure continuously to maintain a stable fabric width across the entire production lot.
Defect Risk
Excessive stress during this drying stage leads to unrecoverable yarn distortion and selvage tearing. The fabric loses its elastic recovery and may develop visible scuff marks where it was pinned to the frame. These structural defects reduce the commercial value of the finished textile and cause problems during lay-planning.
Testing Checkpoint
Verification happens at the exit of the finishing line where technicians check the crimp and grain of the weave.