Reconciling Scouring Mass Loss and Wet Contraction in Landed Linen Fabric Costing
Landed linen costing requires dividing greige linear price by the net length yield factor while netting out chemical scouring mass loss from gross roll weight.
Warp Crimp Takeup
Yarn Contraction
Interlacing warp and weft yarns in a woven structure requires the longitudinal threads to bend around the transverse threads, reducing their straight length. The warp crimp takeup represents the percentage of extra yarn length needed to weave a specific length of fabric. This value is critical for calculating the amount of warp yarn required to produce a target roll length.
Geometrical Measuring
Laboratory technicians determine this contraction by removing a warp thread of known fabric length and stretching it under a standard tension until it is straight. The difference between the straightened yarn length and the fabric length is divided by the fabric length to calculate the percentage. This measurement must be performed under controlled environmental conditions because humidity affects the elasticity of flax yarns.
The collected data is recorded in the weaving sheet to ensure that yarn consumption is predicted accurately for every production run.
Process Calibration
Mill engineers use these calculations to set the warp feed rate and the tension on the loom. High crimp values increase the thickness and elasticity of the finished linen fabric, while low values produce a thinner, stiffer cloth. This relationship helps the mill design fabrics that meet specific weight and density standards.