Yarn Manufacture and Yarn Classification
Yarn Manufacture and Yarn Classification
This domain tests the spinning sequence, yarn numbering, and the vocabulary used to specify a yarn on a fabric order.
Spinning route for cotton
Blow room opens and cleans the fibre; carding individualises fibres into a sliver; drawing doubles and levels slivers; combing is optional and removes short fibres and noil; roving attenuates and adds slight twist; ring spinning drafts, inserts twist, and winds the yarn. Combed yarn is smoother, stronger, and more expensive than carded yarn.
Classification
- Staple or filament; single, plied, or cabled.
- Carded or combed; warp or weft; ring, rotor, or air-jet spun.
- Indirect count Ne: a higher number means a finer yarn. Direct systems: tex (g per 1000 m) and denier (g per 9000 m).
Worked example
A label reads 2/60s cotton. Explain the designation and find the resultant count. The first figure is the number of plies; the second is the single yarn count in Ne. Resultant Ne = single count divided by plies = 60 divided by 2 = 30 Ne. The folded yarn is therefore coarser than 60s singles but finer than 20s singles. In approximate tex terms for cotton, 30 Ne is about 590.5 divided by 30, or 19.7 tex.
Traps that cost marks
Do not reverse S and Z twist. Do not treat Ne as a direct count where a higher number means a coarser yarn. Do not claim combing adds twist; combing removes short fibres. The count of a plied yarn is not the sum of the singles counts.