Modeling Multi-Thread Elasticity and Viscoelastic Stress Relaxation in Ultra High Density Flax Warp Sheets
Dynamic let-off back-stepping and multi-term Maxwell relaxation modeling prevent tension-decay stop marks in dense flax warps.
Warp Sheet
Yarn Alignment
Collective formation of parallel threads that are wound together onto a cylindrical beam for the weaving process. Creation of a warp sheet occurs during the warping stage where hundreds of individual yarn packages are combined into a single flat layer. The threads must be spaced evenly to ensure that the fabric has a uniform appearance and consistent physical properties.
This assembly is the precursor to the sizing and weaving operations in a linen mill.
Tension Uniformity
Control of the force applied to each individual yarn prevents the formation of slack or tight ends in the loom. A warp sheet with uneven tension will cause the fabric to pucker or wave when it is removed from the machine. To maintain this balance, sensors across the warping creel monitor the drag on each yarn and adjust the braking system accordingly.
This precision is especially important for flax yarns which have low elasticity and are sensitive to sudden changes in load.
Beaming Geometry
Final winding of the yarns onto the weaver’s beam must result in a perfectly flat and level surface. Overlapping of yarns at the edges of the beam can lead to entanglement and breakage during the shedding cycle.