1. Yarn Manufacturing Processes
Opening, blending, mixing and cleaning
Typically, mills select bale mixes with the properties needed to produce yarn for a specific end-
use. Processing begins when the bales to be mixed are brought to the opening room, where
bagging and ties are removed. Layers of cotton are removed from the bales by hand and placed
in feeders. The aim is to begin the sequential production process by converting the compacted
layers of baled cotton into small, light, fluffy tufts that will facilitate the removal of foreign matter.
This initial process is referred to as “opening”. The cleaning machines in mills perform the
functions of opening and first-level cleaning. Dust and impurities are removed and blending
The card is the most important machine in the yarn manufacturing process. It performs second-
and final-level cleaning. The card successively work small clumps and tufts of fibres into a high
degree of separation or openness, remove a very high percentage of trash and other foreign
matter, collect the fibres into a rope-like form called a “sliver” and deliver this sliver in a
container for use in the subsequent process.
2. Step 3:
Drawing & Combing
Drawing is the first process in yarn manufacturing that employs roller drafting. Drafting occurs
when a sliver is fed into a system of paired rollers moving at different speeds. Drawing
straightens the fibres in the sliver by drafting to make more of the fibres parallel to the axis of
the sliver. Drawing also produces a sliver that is more uniform in weight per unit of length and
helps to achieve greater blending capabilities. Weight per unit length of a finisher-drawing sliver
is too high to permit drafting into yarn on conventional ring-spinning systems. Combing
upgrades the raw material by removing the short fibers. Combed yarn is more uniform has
greater shine smoother and pure.
The roving process reduces the weight of the sliver to a suitable size for spinning into yarn and
inserting twist, which maintains the integrity of the draft strands. The product is now called
“roving”, which is packaged on a bobbin.
Spinning is the single most costly step in converting cotton fibres to yarn. Bobbins of roving are
placed onto holders that allow the roving to feed freely into the drafting roller of the ring-spinning
frame. Following the drafting zone, the yarn passes through a “traveller” onto a spinning bobbin.
The spindle holding this bobbin rotates at high speed, causing the yarn to balloon as twist is
imparted. The lengths of yarn on the bobbins are too short for use in subsequent processes and
are doffed into “spinning boxes” and delivered to the next process, which may be spooling or
winding. Once the yarn is spun, the manufacturer prepares a correct package. The type of
package depends on whether the yarn will be used for weaving or knitting. Winding, spooling,
twisting and quilling are considered preparatory steps for weaving and knitting yarn. In general,
the product of spooling will be used as warp yarns (the yarns that run lengthwise in woven
fabric) and the product of winding will be used as filling yarns, or weft yarns (the yarns that run
across the fabric).