Managing off Loom Crimp Contraction in Sized Flax Warps
Managing off-loom flax warp crimp contraction requires precise reed denting allowances, ELO tension tuning, and size solubility control to hit target grey widths.
Sanforizing Allowance
Process Calculation
Manufacturing calculations determine the extra length of grey linen fabric required to compensate for the shrinkage that occurs during mechanical compressive pre-shrinking. The sanforizing allowance must be added to the target yardage of the finished cloth when ordering raw woven material from the loom. This factor ensures that the final shipment contains the contracted amount of fabric after mechanical pre-treatment.
Shrinkage Control
Shrinkage control during sanforizing involves passing the damp linen fabric over a heated drum with a thick rubber blanket that compresses the yarns. If the sanforizing allowance is calculated incorrectly, the finished roll of cloth will be too short, which violates the buyer’s agreement and can lead to delivery penalties. Mill planners calculate this value based on the wet-shrinkage test results of each fabric batch.
Yield Management
Yield management in linen mills requires continuous tracking of this metric to optimize the use of raw materials. Fine-tuning the sanforizing allowance allows finishing plants to minimize waste and reduce the cost per meter of pre-shrunk fabric. These calculations are integrated into the mill’s production scheduling software to coordinate the warp length on the looms with the final finished roll lengths.
This coordination prevents shortages and ensures that garment factories receive consistent material dimensions.