Since the natural fibers after basic cleaning (ginning) are transported in a very compressed form in bales to avoid the risk of loss, it becomes necessary to open it. The seed and leaves are usually already removed in the ginning process which leaves the bale pressed with stalk, seed coat, oil, sand, defecation, etc. To remove these impurities, the fibers in the bale are opened in small tufts by the blow process. The blow process is done in the blow room which has machineries to carry out carding. Carding refers to the processes of :
OPENING
1. Willowing 2. Lapping 3. Combing 4. Drawing Willowing (opening) is done in two steps, the entire bale is first opened in small tufts which are then further opened in individual fibers with subsequent passing on the rotor spinning machine. Lapping (dust removal) is done by the action of air flow which along with centrifugal force in a cylindrical chamber causes the dust particle to move away from the fiber and gets collected in a separated part. Combing is done to align all the individual fibers in the same direction using rollers with spikes present at different distances. It starts with combing the fibers with roller which has the spikes placed farthest and subsequently passes them onto narrower rollers which eventually results in a perfectly aligned sliver of fiber. Drawing is done by combining 4 slivers in one. With the increase in drawing, the yarn count can get finer for a better spun yarn. Two or more slivers are combined using drawing process to avoid the irregularities of size and strength in individual slivers. The slivers are then converted directly into rovings because the combined yarn makes it a thick rope. These rovings (or slubbings) are then what are used in the spinning process.
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and
CARDING
