Wet Spinning Trough Softening Physics and Linear Yarn Count Mechanics
Trough water at 70°C hydrolyzes middle lamella pectins to permit inter-fibre slippage, enabling high mechanical drafts down to fine linear yarn counts.
Spinning Triangle
Fibre Convergence
The triangular zone of un-twisted fibres between the nip of the delivery rollers and the first point of twist insertion determines the structure of the spun yarn. This region, known as the spinning triangle, is where drafted flax fibres are fed from the rollers before the rotating traveler inserts the twist. The size and shape of this zone influence the distribution of tension among the individual fibres as they are bound together.
This affects the yarn strength and surface uniformity of the resulting linen yarn. Because flax fibres are relatively stiff compared to cotton, a larger zone leads to poor control over the outer fibres, which results in a rougher yarn surface with higher hairiness.
Twist Insertion
Spinning frame geometry must be optimized to minimize the dimensions of this zone. When the spinning triangle is too wide, the tension on the edge fibres is too high, leading to frequent thread breaks during spinning. Technicians adjust the angle of the roving feed and the height of the thread guide to maintain a compact zone, which is necessary for the efficient production of fine linen yarns.
Breakage Rate
Advanced spinning technologies utilize compact spinning attachments to eliminate this untwisted zone almost completely. By using pneumatic suction or mechanical guides, these devices consolidate the drafted strand before twist insertion. This modification produces a yarn with higher tensile strength and fewer protruding fibres, which improves weaving efficiency on high-speed looms.