Cotton is a natural fiber produced in fields. A fruit of Cotton fibers are attached with the seeds. After plucking from cotton plants the fibers along with seeds are processed in ginning. In the ginning machines, main focus is to separate cotton fibers from seeds. But some-how few seeds get crushed and so the cotton along with seed coats and trash is packed in bale form and supplied to the spinning mills.
In cotton spinning, the first action is managed and controlled by the sequence of machinery known as blow room. The main objective of blow room is to separate good fibers from impurities like – dust, leaves, trash, seed coats and lint.
The waste extracted is known as blow room droppings. Good quality of yarn, fibers should be free from these impurities gor spinning. In general the amount of waste extraction is decided on the trash contain in cotton mixing.
Beaters and air flow are the main components engaged in beating and opening of fibers along with transportation of fibers and removal of impurities. During beating some of the fibers get damaged/broken, and during transportation through air flow some long/short/damaged/immature fibers get converted into a ball form called neps.
Neps are the ball formation of fibers created due to entanglement of fibers and may also have tiny size seed coats with it.
So it can be concluded that fibers damage and neps generation are the by-product of blow room process and to minimize these issues, there is a continuous development taking place in the machine design and in machinery components.
Concept of pull room effect
If lumps of fibers opened and cleaned without any beating and air transportation it would result in reduced fiber damages and lower nep generations. This will further enhance the yarn quality with lower process flow.
By eliminating the series of existing beating and opening machinery, pull zone may be introduced. This will solve the main objective of removing impurities and opening of fibers, with ensured lower neps generation and lower fiber damages.
The main component this proposed pull zone is ‘Match box’/’Tik Tok’ lattice, which has a capacity to extend and shrink during its engagement in pull zone. The lattice has pins on its surface which hold the fibers and during stretch, pulls the fibers from the bunch.
The lattice along with the series of pins is mounted over a pair of rolls; the speeds of the front roll would be double against the back roll, this introduces draft effect. Therefore the 200% draft is introduced in a pull zone hence the fibers are pulled from each other within the bunch.
This results in to the separation of fibers and simultaneously waste gets separated from fibers and is disposed of through the series of grid bars.
There can be certain numbers of pull zones. Every pull zone will add 200% draft in the feed material and it can be imagined the total draft in the series of pull zone would separate every fiber without damaging it.
In fabric, contamination is considered a major fault. Mills control these faults by installing various costly machines in blow room and winding. If we closely see we find that in existing blow room one piece of contamination is broken into 100 or 1000 pieces due to the beaters.
And these small pieces are tried to arrest by installing contamination/PP cleaners. With this new pull room concept, the PP/contamination will not be broken in to small pieces and so there would be better control over contamination/PP in the yarn.
In the existing blow room, there is a huge power consumption required to work air supply and the number of beaters.
The proposed pull room effect would save huge power as the series of beaters from existing blow room would be eliminated, and also the amount of air suction required for the proposed arrangement would be very low.
