Correlation between Sizing Penetration Ratio and Rapier Weaving Efficiency Rates
Sizing penetration ratios between twenty and twenty-five percent minimize rapier yarn abrasion while preserving elasticity for peak loom efficiency.
Squeezer Roll Hardness
Pressure Regulation
Sizing machine parameters control the pick-up of protective adhesives on spun yarns by regulating the mechanical squeeze during liquid extraction. The squeezer roll hardness determines the compression of the rubber-covered roller against the yarn sheet, which dictates the amount of size left in the flax warp. In linen mills, this setting is measured in Shore degrees to ensure consistent sizing pick-up across the entire warp sheet.
It prevents uneven drying and tension variations on the loom.
Absorption Control
Selecting the appropriate roller hardness involves a balance between size penetration and wet pick-up. A softer roll has a wider nip area, which applies a gentler pressure and leaves more sizing paste on the yarn surface, a condition suitable for coarse flax fibres. Conversely, a harder roller concentrates the pressure in a narrower nip, forcing the sizing liquid deeper into the core of fine linen yarns while squeezing out the excess.
If the roller is too hard, it can damage the delicate yarn structure and leave insufficient size on the surface. Sizing operators monitor this hardness regularly using a durometer. This step ensures the roller does not degrade or become unevenly worn over time.
Moisture Removal
Maintaining uniform roller compression prevents the warp from carrying excess moisture into the drying cylinders. High moisture levels increase the energy required to dry the yarn, which raises the processing costs and can cause the sizing film to stick to the hot metal surfaces. Proper calibration of the squeezer rolls avoids these drying issues and ensures a smooth warp sheet.