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CHAPTER IX
PROCESSING COTTON TO SPIN YARN
i) Beater or Pre-operator
ii} Drum attached draw frame
iii) Carding and
iv) Drawing Frame
Cotton is purchased from the Cotton Market by bale, the quality of Cotton may be, either, ! 147, J 34, F 141, 797 or Kalyan cotton etc., for the purpose of spinning yarn.
The Cotton is, therefore, processed by, "Cotton Processing Unit". The whole UNIT consists of the following machines.
A. BEATER : Cleaning the Cotton
B. DRUM ATTACHED : The cleaned cotton - thereafter to make uniform lap
C. CARDING MACHINE : Cards cotton - delivers card sliver
D. DRAWING FRAME : To make slivers uniform for desired the count of yarn
E. ROVING UNIT : It is required only to spin the fine age count of yarn.
YARN is identified by its count. The count means, uniformity appearance and strength. Higher the count is, the thinner is the yarn. Count 4, 6, 10, 70, 40, 80, 100, etc., these counts of yarn are known as single yarn : When we say 2/6, 2/10, 2/20, 2130, 2/40, 2/80, 2/100 etc., these types of yarn (these counts of yarn are known as double or twisted yarn). The double or twisted yarn is stronger than the single yarn and more durable but costlier than the single yarn. Generally in good and strong quality of cloth, the warp is made of double yarn.
Ambar Charkha spins upto 30 count of-yarn, i.e. the finest count possible without the use of 'Roving Unit'. The yarn that is spun in the Ambar Charkha from the sliver made without the help of Roving Unit, falls between 10 to 20 count, depending upon the efficiency of the Ambar Charkha.
There are FOUR STAGES to process the 'cotton', before yarn is spun by the Ambar Charkha.
A. BEATER
Beater is simple mechanical device to open Pressed and half pressed cotton. It is operated by 1/2 H.P. Motor. The Beater consists of :
i) A pair of fluted rollers pressed together and set in motion for the regular feeding
ii) A spiked cylinder arranged immediately after the fluted rollers for breaking the cotton.
iii) A fan unit in front of the spiked cylinder for driving the opened cotton into the collection box.
B. DRUM ATTACHED DRAW FRAME :
The machine consists of three roller drafting system with a total draft of six. A weight roller is held over the front roller on which a revolving drum is held on brackets.
Required quantity of open cotton is weighed and spread evenly on the feed plate and the lap end delivery by front roller is taken over the drum. This process is repeated 3 to 4 times to form uniform lap. This lap is fed to the Carding Machine. the Drum is operated with 1/2 H.P. Motor.
C. CARDING MACHINE
The Carding Machine cards the cotton and delivers 'Card Sliver'. It consists of three distinct functional zones, namely:
i) Feeding Zone ii) Carding Zone iii) Delivery Zone
i) In feeding zone, the lap is 'attenuated', i.e., to make thin by the drafting rollers. the drafted lap is fed into the carding zone.
yarn
ii) in the carding zone, with the help of revolving 'doffer combs' the cotton is 'opened' and 'blown' to the condenser zone after eliminating the heavy particles and other impurities into the dust collection box.
iii) The delivery end consists of a pair of perforated condenser cylinders followed by a pair of calendar rollers. The perforated cylinders roll out thin layer of carded cotton and feed them to the calendar rollers which condense it into Card Sliver. the Card Sliver thus delivered, is collected in a rotating collection pot.
D. DRAWING FRAME
The 'Card Sliver' obtained from the carding machine is not of uniform thickness and of desired count. The fibres inside the sliver are not properly parallelised. Therefore, predetermined end of card sliver are fed into the drawing frame through repeated drawing operations. The number of ends and the repeat operation are governed by the count of the final sliver required.
The drawing frame has two roller drafting system having a total draft of 4. The attenuated sliver is condensed in between the calendar rollers and is delivered into a slowly rotating collection pat and the same is taken out in convenient length.
It is operated by a 1/2 H.P. Motor.
The drawing frame is mounted on a square pipe frame.
E. ROVING UNIT:
The Roving Unit consists of a three roller drafting system and a four spindle twisting arrangement. The final sliver obtained from drawing frame is drafted from the drafting zone and thin strands delivered out of front rollers are twisted and wound on bobbin with the help of the rings and travellers.
This is actually a device similar to that of spinning, but for giving lesser twist to the strand. The roving so prepared is used to feed the Charkhas.
The machine is hand operated (manually), just like the operation of Ambar Charkha.
Sliver may be defined as a continuous, ropetike strand of loosely assembled fibres without twist that is approximately uniform in cross-sectional area. This is the state of fibres after they have been carded, in this form they may be drawn (and thus reduce in bulk) from the card by the 'drawing frames'.
SPINNING YARN WITH AMBAR CHARKHA FROM THE SLIVER MADE:
Two Spindle Ambar Charkha are being used to spin yarn, from the sliver made by the cotton processing unit, by Profound and Severe grade of mentally handicapped persons. It is a productive occupation but not so remunerative. It is easy to operate by hand and repetitive too. just to turn the handle which is attached to the wheel of the Charkha. Here, also such persons are trained to turn the wheel of the Charkha without any jerk, as well as, their eyes are trained to notice when the thread breaks and should it break, they should know how to join it which is very simple to do and continue to work or rotate the handle of the Charkha.
DETAILS OF TWO SPINDLE AMBAR CHARKHA :
Two spindle Ambar Charkha is a small ring spinning frame with two spindles in a row and one roller apron drafting system and TOP-ARM weighting arrangement.
The rovings, arranged from a creel stand at the top of the charkha are fed to the drafting system through condensers and two ends delivered out of the front rollers are twisted by the revolving spindles and then wound on the bobbins with the help of rings and travellers. The charkhas are suitable to spin different counts from 10 to 30 depending upon the efficiency of the machine (charkha).
The Ambar Charkha of two Spindle is operated by hand, i.e. (manually).
TO SUM UP
Two Spindle Ambar Charkha is an ideal occupation for the mentally handicapped persons, especially those who fall under Profound, Severe and to some extent Moderate Grade of mental handicaps. It is not only safe but also very simple to operate. Though Ambar Charkha spinning is not that remunerative occupation but indeed it is a boon to keep their mind occupied in constructive work. It can be called a type of productive work.
It is to create employment opportunity to Profound and Severe grade of mental handicaps in a Sheltered Workshop. It is safe and easy to operate. Investment for this charkha is negligible and a few square feet are required for operation of the Charkha.
A good amount of incentives may be given to them to keep up their interest in the work.
Payments to the handicapped workers may be considered not only on the basis of the quantity that one produces, but also how long one is occupied in this jab without any problem.
It may be used as a SELF EMPLOYMENT tool and may be that at a later stage he or his family may improve the quality of life by earning a little more.
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