In textile spinning, yarn realisation (YR), or yarn recovery, is an operational parameter of yarn manufacturing. It is the percentage conversion of raw material to finished yarn. The rest of the waste fibers with less value are compared to the weight of the produced yarn from a given weight of raw material. The quantity of waste removed during the various phases of yarn spinning, such as blow-room, carding, and combing, is often used to determine yarn realisation.[1][2][3][4] Yarn realisation ranges between 85% and 90% in carded cotton yarns and between 67% and 75% in combed cotton yarns.[5]

Significance

Yarn realisation is one of the important factors that affect the quality of the yarn, profitability, and lead time of a spinning mill.[6][7][3] Better realisations make spinning mills more competitive, and greater realisations mean better economics for a spinning business. Even minor changes in yarn realisation, say 1%, translate into a huge impact on spinning production economics.[1] Thus, controlling yarn realisation is as critical to a mill as controlling cotton and mixing costs.[8]

Formula

Components

The following components play a significant role in yarn realisation:

Raw material

In the spinning industry, the cost of raw material is directly influenced by: procurement, methods of mixing, yarn realisation (waste standards), and re-use of waste.[9] After picking, the cotton lint in compressed bales is transferred to the yarn spinning mills.[10][11]

Cotton lint

Cotton lint refers to the fibrous coat that covers the cotton seeds. Cotton lint is ginned cotton. The lint that is delivered to the spinning mill contains a variety of extraneous materials, including seed pieces, dust, and motes, which are collectively referred to as trash. Yarn realisation (YR) is largely influenced by the trash content of cotton, the intended yarn quality, and the type of machinery used.[12][13]

Trash percentage

Trash is non-lint material that is present with cotton lint. It is made up of leaf fragments, bark bits, grass, plastic pieces, sand, and dust. The level of contamination is determined by cultivation, harvesting, and ginning conditions.[14]

Short fibers

Cotton is a natural plant fiber, and depending upon many conditions, such as geography, seed quality, and cultivation, the length of the fiber varies from lot to lot, as well as different qualities.[15][16][17] Increased efficiency in yarn manufacturing and yarn quality are dependent on certain fiber characteristics.[18] For an example short fiber content (SFC) by number and by weight influences the productivity and quality of the yarn. Cotton lint with more than 25%SFC(n) is a problem in spinning.[2][19][20] Short fibers also known as "noil" extraction improves the yarn quality, consequently affects yarn realisation.[21][22] Extra noil extraction is required for superior and fine quality yarn, which affects the yarn realization.[2]

Moisture

Cotton is a hygroscopic fiber, which means it takes in moisture from the environment and also dries quickly if it is kept in a dry place. A small amount of moisture loss in the lint may also contribute to yarn realisation.[23]

Humidification

To maintain a specified level of moisture in cotton, the relative humidity must be maintained at 65 percent during mixing, winding, and packing. Moisture helps in reducing fluff generation and decreasing in invisible losses.[2]

Spinning

Spinning is a process in textile manufacturing in which staple fibers are converted into yarn. Optimizing spinning processes and waste management benefits the yarn realisation and the economics of a spinning mill.[24][25]

Preparatory

Mixing of cotton

Cotton fibers vary in terms of staple length and other physical qualities; it is an inherent characteristic.[2] Bale mixing, or bale management is the process of testing, sorting, and then mixing fibers from different bales [also include the bales received from different stations] according to their fiber qualities in order to produce a certain quality yarn at the lowest possible cost.[26]

Spinning methods

Waste management

The waste in textiles is classified into two types: production waste, which is the raw material for subsequent steps in spinning production (it is cleaning waste left out short fibers in carding or combing, it is a reusable waste). Post-production waste that is not related to spinning, but does happen at the stages of yarn to fabric [manufacturing and processing]. Waste management in spinning contributes to better yarn realisation.

The two types of waste that contribute to yarn realisation are: one is hard waste, which is not reused, and the second type of waste is reusable waste, also called soft waste, which includes sliver bits, lap bits, roving ends, roller waste, and pneumafil.[24]

Recycled yarn

Yarn produced from the waste fibers can reduce the losses and contribute to the mill's profitability. There are many areas where waste fibers can be used, such as blending.[27]

See also

References

  1. ^ a b Thilagavathi, G.; Karthik, T. (2016-01-05). Process Control and Yarn Quality in Spinning. CRC Press. pp. 69, 70, 71. ISBN 978-93-80308-18-0.
  2. ^ a b c d e "Yarn recovery: The He(art) of spinning - Indian Textile Journal". 2022-01-28. Retrieved 2022-04-06.
  3. ^ a b Bhatia, S. C. (2017-10-26). Pollution Control in Textile Industry. CRC Press. p. 305. ISBN 978-1-351-37305-0.
  4. ^ "SITRA's 36th Costs, Operational Performance & Yarn Quality (CPQ) Study". SITRA. Retrieved 2022-04-09.
  5. ^ Kumar, R. Senthil (2014-09-23). Process Management in Spinning. CRC Press. pp. 346, 347. ISBN 978-1-4822-0836-8.
  6. ^ Ratnam, Tarakad Vedamurthy (1993). A Decade of SITRA's Research, 1981-82 to 1990-91. South India Textile Research Association. p. 87.
  7. ^ Anand, K. T.; Rajan, A. John; Narayanan, K. V. (2015). "Factors Affecting Leadtime in Spinning Mills". Applied Mechanics and Materials. 813–814: 1154–1164. doi:10.4028/www.scientific.net/AMM.813-814.1154. ISSN 1662-7482. S2CID 111591834.
  8. ^ "Quality Improvement of Yarn by Automatic Waste Removal" (PDF). International Journal of Emerging Technologies in Engineering Research (IJETER). 6 (1).
  9. ^ Association, Bombay Textile Research (1966). Proceedings of the Annual Technological Conference. p. 27.
  10. ^ Sen, Ashish Kumar (2001-05-08). Coated Textiles: Principles and Applications. CRC Press. p. 59. ISBN 978-1-4200-3192-8.
  11. ^ "The Story of Cotton- How Cotton is Ginned and Marketed". www.cotton.org. Retrieved 2022-04-09.
  12. ^ "Cotton Lint - an overview | ScienceDirect Topics". www.sciencedirect.com. Retrieved 2022-04-07.
  13. ^ "Cotton lint Definition". Law Insider. Retrieved 2022-04-07.
  14. ^ "2.2.10-Cotton Value Addition-Trash (non-lint) content". www.cottonguide.org. Retrieved 2022-04-07.
  15. ^ "Natural Plant Fiber - an overview | ScienceDirect Topics". www.sciencedirect.com. Retrieved 2022-04-07.
  16. ^ "Cotton Fibre - an overview | ScienceDirect Topics". www.sciencedirect.com. Retrieved 2022-04-07.
  17. ^ Fang, David D.; Percy, Richard G. (2020-01-22). Cotton. John Wiley & Sons. ISBN 978-0-89118-625-0.
  18. ^ "Fibre Strength - an overview | ScienceDirect Topics". www.sciencedirect.com. Retrieved 2022-04-07.
  19. ^ "Short Fibre Content in Cotton Is It The Next Big Challenge for Spinners? Continued Part 2". Texcoms Worldwide. 2020-05-15. Retrieved 2022-04-07.
  20. ^ Zeidman, Mishu I.; Batra, Subhash K.; Sasser, Preston E. (1991). "Determining Short Fiber Content in Cotton". Textile Research Journal. 61 (1): 21–30. doi:10.1177/004051759106100103. ISSN 0040-5175. S2CID 135638967.
  21. ^ Rutnagur, Sorabji M. (2006). The Indian Textile Journal. Business Press. p. 17.
  22. ^ Purushothama, B. (2016-01-05). Handbook on Cotton Spinning Industry. CRC Press. p. 239. ISBN 978-93-85059-55-1.
  23. ^ Shaikh, Tasnim N.; Agrawal, Sweety A. (2017-12-06). Engineering Cotton Yarns with Artificial Neural Networking (ANN). CRC Press. p. 46. ISBN 978-1-351-18625-4.
  24. ^ a b Nayak, Rajkishore (2019-12-01). Sustainable Technologies for Fashion and Textiles. Woodhead Publishing. p. 49. ISBN 978-0-08-102868-1.
  25. ^ Textile Trends. Eastland Publications. 2003. p. 17.
  26. ^ "Bale Opener - an overview | ScienceDirect Topics". www.sciencedirect.com. Retrieved 2022-04-07.
  27. ^ Nayak, Rajkishore; Patnaik, Asis (2021-01-07). Waste Management in the Fashion and Textile Industries. Woodhead Publishing. p. 78. ISBN 978-0-12-818759-3.
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