Mechanical Control
Force applied to the filling yarn as it is carried across the warp shed. Controlling the weft insertion tension is necessary for achieving a uniform fabric width and preventing the formation of loops or tight picks. Flax yarns, which lack the elasticity of cotton, require precise tensioning to avoid breakage during high-speed rapier or air-jet production.
Operating Force
Accumulators and brake systems on the loom regulate the speed at which the yarn leaves the supply package. If the weft insertion tension is too low, the yarn may kink or snag, creating a defect known as a snarl in the linen cloth. Proper settings ensure that the yarn remains straight and taut until the reed pushes it into the fabric fell.
Quality Outcome
Measurements are taken using electronic tensiometers during the production cycle to maintain a consistent profile across the entire roll. High tension leads to excessive draw-in and may cause the selvedge yarns to snap under the stress of the beat-up. Maintaining a stable weft insertion tension results in a flat, even surface that is easier to process during the bleaching, sizing, finishing and dyeing stages of linen production.
This measurement is tracked in the loom efficiency log.