Warp Preparation and Sizing Standards for Wet Spun Linen Yarns
Optimal wet spun linen weaving requires low viscosity binder penetration, pneumatic water splices, and eight percent size pickup to maintain loom shed efficiency.
Pneumatic Squeeze Pressure
Force Regulation
Compressive forces applied by rollers in a sizing machine regulate the quantity of adhesive left on the yarn. Adjusting the pneumatic squeeze pressure allows operators to control how much liquid is squeezed out of the flax yarn after it passes through the size bath. This pressure is generated by compressed air cylinders acting on rubber and steel rollers.
Operators record the target pressure values on the batch sheet to maintain uniform treatment conditions.
Pickup Optimization
The level of applied force affects both the penetration of the size and the moisture content of the warp before drying. Optimizing the pneumatic squeeze pressure prevents the yarn from carrying excessive sizing mixture, which would waste materials and make the yarn brittle. If the force is set too low, the wet yarn holds too much water, requiring more energy and time in the drying ovens, which can damage the delicate flax fibers.
Quality Verification
Calibration logs and dial indicators on the machine console show the active force exerted on the roller ends. To maintain the highest product quality, the mill’s technical standards specify the exact pneumatic squeeze pressure for each linen yarn count. Technicians measure yarn density and check size absorption in the quality control laboratory to confirm that the rollers are pressing evenly across the width of the yarn sheet.
When uneven pressure occurs, it causes variations in yarn properties, which can result in fabric defects and a lower grading for the finished linen cloth. Therefore, the pneumatic system is calibrated at the start of each production cycle, and the pressure settings are locked to prevent unauthorized changes during the weaving process.