Optimizing Wet Pick up Values in Flax Warp Slashing
Optimizing flax wet pick-up between 80 and 95 percent balances film encapsulation with core penetration, minimizing loom warp breaks and sizing liquor cost.
Shore a Roll Hardness
Indentation Scale
Mechanical property quantifies the resistance of a rubber or elastomer surface to indentation by a spring loaded metal pin. Durometer readings indicate the density of the squeeze rolls used in the flax slasher or wet spinning frames. Maintaining the shore a roll hardness is necessary for ensuring uniform pressure distribution across the entire width of the yarn sheet.
Values typically range from fifty to ninety on the scale depending on the specific stage of production.
Hardness Variance
Softer rolls with lower readings allow for a longer nip contact area and deeper liquor penetration. When the shore a roll hardness increases due to aging or chemical degradation, the sizing pickup becomes uneven and leads to weaving defects. Regular calibration prevents the rolls from becoming too stiff to accommodate the natural variations in linen yarn thickness.
Maintenance Routine
Technicians press the gauge firmly against the roll cover at multiple points along the circumference to identify flat spots or hardened zones. Replacing a roll that has lost its elasticity preserves the integrity of the flax fibers by avoiding localized crushing. This maintenance step is a standard part of the quality control routine in modern spinning mills where precise liquor management determines the final fabric hand.
Frequent monitoring ensures that the rubber does not dry out and crack under the high temperatures of the sizing bath.