TX4011 Theory of Drafting Syllabus:
TX4011 Theory of Drafting Syllabus – Anna University PG Syllabus Regulation 2021
OBJECTIVE
To enable the students to learn about the theory of drafting process and drafting irregularities
UNIT I DRAFTING
Definition of ideal drafting, model; conditions required to achieve ideal drafting in a roller drafting system; deviations from ideal draftingduring actual drafting; definition of drafting wave; condition for drafting wave formation during roller drafting; estimation of the magnitude of the irregularity caused by the occurrence of drafting wave.
UNIT II DRAFTING FORCE
Roller drafting – forces acting on a fibre during drafting at different positions in drafting zone; measurement of drafting force; factors affecting drafting force; methods to avoid drafting wave formation; role of apron in controlling drafting wave formation; limitations of apron in roller drafting system
UNIT III OTHER DRAFTING IRREGULARITIES
Definition of roller slip; conditions for the formation of forward and backward slips in the roller drafting systems; measures to avoid roller slip occurrence, causes for roller nip movement, model; roller speed variation during drafting and their effect on irregularity formation; control of the irregularity formed due to these sources.
UNIT IV COMPARISON
Comparison of roller drafting system with wire point drafting system; application of wire point drafting in card and rotor spinning machine; comparison of roller drafting in drawframe, comber preparatory, comber, speed frame, ring frame and air-jet spinning system
UNIT V COMPACT SPINNING
Spinning triangle – formation, factors affecting dimensions, effect on yarn quality; condensed yam spinning – principle, different methods
TOTAL 45 PERIODS
OUTCOMES:
On completion of this course, student would understand
CO1: Theory of ideal drafting and formation of drafting wave
CO2: Drafting force its measurement and influence
CO3: Different causes for irregularities in textile strand
CO4: Comparison of wire and roller drafting system and the drafting systems used in different spinning machinery
CO5: Compact spinning, principle and different methods
REFERENCE:
1. Foster G.A.R. The Principles of Roller Drafting and the Irregularity of Drafted Materials, The Textile Institute, Manchester, 1958.
2. Klein W. A Practical Guide to Combing, Drawing and the Roving Frame, The Textile Institute, Manchester, 1999.
3. Lord P.R. Roller Drafting, Textile Progress, The Textile Institute, Manchester, 1993.
4. Grosberg P and lype C. Yarn Production: Theoretical Aspects, The Textile Institute, Manchester, 1999.
5. Lord P.R., Yam Production: Science, Technology and Economics, The Textile Institute, Manchester, 1999.