Spinning Triangle and Twist Triangle
topic
The spinning triangle (twist triangle) is the region between the front roller nip and the yarn formation point where the flat drafted ribbon of fibres converges to form a twisted yarn. Its base width is the drafted ribbon width (1–3 mm) and its apex is the yarn body. Edge fibres at the periphery of the triangle are under higher tension than central fibres, causing them to break and protrude as hairiness. Compact spinning eliminates the triangle by condensing fibres before twist insertion.
Role
The spinning triangle is the structural origin of yarn hairiness, which is the key surface quality parameter differentiating ring-spun from compact-spun yarns. Understanding the triangle's geometry explains why hairiness increases with coarser yarn counts and higher spindle speeds, and is the theoretical foundation for designing compact spinning attachments that improve fabric quality.