Contents
Acknowledgments ……………………………………………………………………………. ix
1 Review of yarn production …………………………………………………………………. 1
1.1 Historical basis ………………………………………………………………………….. 1
1.2 Present day conditions ……………………………………………………………….. 8
1.3 Future of the means of textile production …………………………………….. 9
1.4 Modern production systems………………………………………………………. 10
References ………………………………………………………………………………. 17
2 Textile products and fiber production ……………………………………………… 18
2.1 Textile materials (fabrics, fibers, and filaments) …………………………. 18
2.2 Natural fibers (types and production) ………………………………………… 22
2.3 Man-made fibers (polymer extrusion and yarn production) …………. 38
References ………………………………………………………………………………. 54
3 Common principles ………………………………………………………………………… 56
3.1 Introduction …………………………………………………………………………….. 56
3.2 Twist in strands ……………………………………………………………………….. 56
3.3 Twist insertion …………………………………………………………………………. 61
3.4 Confined and non-confined systems ………………………………………….. 67
3.5 Twist evenness …………………………………………………………………………. 68
3.6 Tension control ………………………………………………………………………… 69
3.7 Drawing ………………………………………………………………………………….. 70
3.8 Consequences of roller errors on the textile product …………………… 76
3.9 Control of irregular flow in drawing or drafting …………………………. 77
3.10 Doubling …………………………………………………………………………………. 83
3.11 Effects of shear ………………………………………………………………………… 84
3.12 Integration of sub-processes ……………………………………………………… 86
References ………………………………………………………………………………. 87
4 Filament yarn production ……………………………………………………………….. 88
4.1 Introduction …………………………………………………………………………….. 88
4.2 Texturing filament yarns …………………………………………………………… 89
4.3 Real twist texturing ………………………………………………………………….. 90
4.4 False twist texturing …………………………………………………………………. 92
4.5 Draw-texturing ……………………………………………………………………….. 102
4.6 Stuffer box texturing ………………………………………………………………. 104
4.7 Air-jet texturing ……………………………………………………………………… 106
4.8 Other texturing techniques ………………………………………………………. 110
4.9 Industrial filaments ………………………………………………………………… 113
4.10 Silk filaments and staple yarns ……………………………………………….. 113
4.11 Morphology and dyeing ………………………………………………………….. 114
References …………………………………………………………………………….. 114
5 Carding and prior processes for short-staple fibers ……………………….. 116
5.1 Introduction …………………………………………………………………………… 116
5.2 Opening line ………………………………………………………………………….. 118
5.3 Bale preparation …………………………………………………………………….. 119
5.4 The first stage of blending and opening …………………………………… 121
5.5 The process of disintegration of fiber clumps …………………………… 122
5.6 Condensation …………………………………………………………………………. 123
5.7 The process of cleaning ………………………………………………………….. 125
5.8 Intimate blending …………………………………………………………………… 129
5.9 Fiber flow ……………………………………………………………………………… 133
5.10 Carding …………………………………………………………………………………. 136
5.11 Waste control …………………………………………………………………………. 149
5.12 Safety ……………………………………………………………………………………. 153
References …………………………………………………………………………….. 154
6 Sliver preparation …………………………………………………………………………. 155
6.1 Introduction …………………………………………………………………………… 155
6.2 Drawframe …………………………………………………………………………….. 155
6.3 Combing ……………………………………………………………………………….. 159
6.4 Creel blending ……………………………………………………………………….. 164
6.5 An industrial case study ………………………………………………………….. 165
References …………………………………………………………………………….. 167
7 Short-staple spinning ……………………………………………………………………. 168
7.1 Ring spinning ………………………………………………………………………… 168
7.2 Open-end spinning …………………………………………………………………. 185
References …………………………………………………………………………….. 203
8 Long-staple spinning …………………………………………………………………….. 205
8.1 Introduction: Effects of lengthening the staple …………………………. 205
8.2 Wool fibers and their preparation ……………………………………………. 206
8.3 Worsted systems …………………………………………………………………….. 213
8.4 The woolen system …………………………………………………………………. 220
8.5 Bast fiber spinning processes ………………………………………………….. 231
References …………………………………………………………………………….. 232
9 Post-spinning processes …………………………………………………………………. 234
9.1 Winding ………………………………………………………………………………… 234
9.2 Yarn joining …………………………………………………………………………… 245
9.3 Ply yarns ……………………………………………………………………………….. 250
9.4 Automation ……………………………………………………………………………. 253
9.5 Two-for-one twisting ………………………………………………………………. 255
9.6 Customer concerns …………………………………………………………………. 257
References …………………………………………………………………………….. 259
10 Staple systems and modified yarn structures …………………………………. 260
10.1 Yarns of complex structure ……………………………………………………… 260
10.2 Processes using modified twist ……………………………………………….. 261
10.3 Compact spinning…………………………………………………………………… 261
10.4 Air-jet spinning ……………………………………………………………………… 263
10.5 Sirospun yarns and process …………………………………………………….. 268
10.6 Hollow spindle spinning …………………………………………………………. 270
10.7 Self-twist spinning …………………………………………………………………. 271
10.8 Twisted self-twist yarns and processes …………………………………….. 274
References …………………………………………………………………………….. 275
11 Quality and quality control …………………………………………………………… 276
11.1 Quality ………………………………………………………………………………….. 276
11.2 Quality control ………………………………………………………………………. 278
11.3 Yarn evenness ………………………………………………………………………… 291
11.4 End-breaks and quality …………………………………………………………… 298
References …………………………………………………………………………….. 300
12 Economics of staple yarn production …………………………………………….. 301
12.1 Yarn economics ……………………………………………………………………… 301
12.2 Productivity …………………………………………………………………………… 303
12.3 Quality and economics……………………………………………………………. 306
12.4 Cost minimization ………………………………………………………………….. 308
12.5 Operational factors …………………………………………………………………. 313
12.6 International competition ………………………………………………………… 315
References …………………………………………………………………………….. 316
Appendices …………………………………………………………………………………… 317
1. Calculations I: Elementary theory ………………………………………………. 317
2. Calculations II: Worked examples ………………………………………………. 329
3. Advanced topics I: Air conditioning and utilities …………………………. 341
4. Advanced topics II: Testing of textile materials …………………………… 350
5. Advanced topics III: Staple yarn structures …………………………………. 373
6. Advanced topics IV: Textured yarn structures ……………………………… 383
7. Advanced topics V: Blending of staple fibers………………………………. 389
8. Advanced topics VI: Drafting and doubling ………………………………… 407
9. Advanced topics VII: Yarn balloon mechanics …………………………….. 427
10. Advanced topics VIII: Topics in rotor spinning ……………………………. 453
Index ………………………………………………………………………………………………………… 465
Acknowledgments
Grateful acknowledgments are made to the many friends and colleagues who have read various parts of this script and given very helpful and constructive criticism. These include Charles Chewning, David Clapp, Philip Dabbs, Yehia E1 Moghazi, Wally Johnson, W Oxenham, Jon Rust and W C Stuckey.
Acknowledgments are also made to UMIST, NC State University, Cotton Incorporated, the many different commercial organizations in a variety of fields with whom I have been associated and the many people involved. It has been a great experience and pleasure. Much of what I have to say in this book has its origins in the many discussions and shared fieldwork experiences. This embraces too large a number of people to name individually but I take the opportunity to express my thanks to all of you. I hope that by sharing these experiences, I will repay the help that I have received during my career in this fascinating field.
I would be remiss in not acknowledging the wonderful forbearance of my wife Mavis during these last years. Only someone that cared so much could have tolerated the late arrivals for meals, the relegation of important social responsibilities and the overwhelming obsession with the project. I dedicate the work to her in celebration of our 56th wedding anniversary.