Flax Roving Wet Spinning Attenuation Defect Mechanisms
Flax roving wet spinning attenuation defects stem from improper hot-water pectin softening and front roller nip slip, manageable through precise temperature and pressure control.
Nip Pressure
Compression Force
Compressive mechanical force applied at the contact line between two opposing rollers regulates fiber movement during drafting and controls fabric thickness during calender finishing. Precise nip pressure adjustments prevent fiber slippage in flax wet drafting zones while maintaining uniform liquid extraction across squeeze rollers. Incorrect load distribution across the roller face causes uneven yarn count or streaky luster on finished linen cloth.
Mechanical Contact
Pneumatic or hydraulic loading systems exert downward force on top roller pivots to maintain uniform contact along the entire roll face. In wet spinning frames, weighted top rollers press the lubricated flax bundle against driven steel bottom rollers, establishing the mechanical grip necessary to draft fiber bundles smoothly without crushing individual filaments. Hardness of the rubber roller cover modulates the width of the contact zone, distributing pneumatic load across a narrow footprint.
Inadequate loading allows unattenuated roving clumps to pass into the twisting zone, generating thick slubs. Excess pressure accelerates roller cover wear and fractures delicate flax fibers, creating short-fiber waste.
Fiber Threshold
Maximum pressure thresholds depend on fiber fineness and moisture content within the strand. Heavy flax coarse counts tolerate higher nip loading than fine yarn counts, which shear under intense mechanical clamping.