3. Fiber: A unit of matter characterized by flexibility, fineness, sufficient strength, elasticity and a high length to width ratio.
Spinning: Spinning is the process where fibers are converted into yarn.
Yarn: A grouping of fibers twisted together to form a continuous strand.
Md. Yousuf Hossain, Green University Of Bangladesh, yousuf_te@yahoo.com
6. Functions/ Objectives
To produce required count of yarn from the supplied roving by drafting.
To insert sufficient amount of twist to the yarn.
To attenuate the roving until the required fineness of the yarn is achieved.
To wind the yarn onto the bobbin.
To build the yarn package properly.
10. (2)Drafting Zone:
At the ring spinning frame greatest value of draft is given.
The drafting zone of the ring frame is the most important part of the machine that directly influences the evenness and strength of the yarn.
All the modern ring spinning frame use a 3 over 3 roller drafting with both the top and bottom middle rollers covered with aprons.
Md. Yousuf Hossain, Green University Of Bangladesh, yousuf_te@yahoo.com
11. (2)Drafting Zone:
The bottom rollers are steel fluted and driven positively. The top rollers are covered with synthetic rubber coating and driven by the frictional contact with the bottom rollers.
For this purpose the top rollers are weighted by using spring, pneumatic or magnetic weighting with the help of a pendulum arm.
A total draft of 15 to 40 and in some cases even up to 50 can be given at the ring spinning frame.
Md. Yousuf Hossain, Green University Of Bangladesh, yousuf_te@yahoo.com
12.
13. •The yarn then passes through a traveller on to the yarn package (cop).
•The cop is mounted on the spindle and rotates with the spindle.
•When the cop rotates the tension on the yarn pulls the traveller to rotate around the ring.
14. The yarn after being twisted by the traveller has to be properly wound on the package called as the cop.
In order to the winding there should be a difference in the surface speed between the spindle and the traveller.
The traveller has no drive of its own instead it is carried along with the yarn which is being wound on the cop after passing through the traveller.
15.
16. •Higher traveller velocity.
•Longer Machines (1488 spindles available).
•Improved drafting system.
•Smaller ring sizes.
•Automatic doffing.
•Auto piecing.
•Higher draft ranges (more than 100).
•Data collection system (Ring Data).
17. •Any type of material (fiber) can be spun.
•Wide range of count can be processed.
•It is uncomplicated and easy to operate.
•Higher yarn strength can be achieved.
•Finer yarn can be produced.
Md. Yousuf Hossain, Green University Of Bangladesh, yousuf_te@yahoo.com
18. •Energy cost is very high.
•Machine generates more heat.
•The capacity of the cop is limited.
Md. Yousuf Hossain, Green University Of Bangladesh, yousuf_te@yahoo.com