Spun Yarn Technology

1 Introduction Yarn Continuous Filament Production Continuous Filament Yarn Continuous Filament Tow Spun Yarn Production Drafting Doubling Spun Yarn Types Basic Operations in the Production of Spun Yarns Terminology of Spun Yarns Yarn Thickness Yarn Count The Tex System General Comparison of Continuous Filament and Spun Yarns Fibre Properties2 Opening and Cleaning Automatic Feeders Raw Wool Impurities and Principles of Removal Raw Cotton Impurities and Principles of Removal Principles of Raw Flax Processing Principles of Raw Jute Processing Principles of Spun Silk Processing3 Blending and Mixing Basic Blending Requirements Blending Systems Blending Tolerances Mixing Deficiencies Limitations of Blending and Mixing4 Carding General Carding Objectives Card Clothing Carding Actions Fettling Grinding Setting Carding Faults Wool Card Roller Arrangement Worsted Carding Semi-Worsted Carding Woollen Carding Cotton Card Arrangement Flax Carding Jute Carding5 Roller Drafting, Doubling, and Fibre Control Draft: Calculated and Actual Doublings Combination of Drafts and Doublings The Drafting Zone Back and Front Rollers Beard Fibres Roller Slip Ratch Floating Fibres 'Perfect' Sliver Levelness Random Fibre Distribution 'Perfect' Drafting Fibre End Distribution Drafting Waves Drafting Force Mechanical Defects Reversal of Draft Direction Square-Cut Staple Fibres Methods of Fibre Control Pin Direct Pressure Twist Combined Twist and Direct Pressure6 Autolevelling Radical Autolevelling Conservative Autolevelling Open Loop Closed Loop Combined Loop Closed Loop Design Deviation Reduction Factor Gain/Frequency Response Phase-Lag/Frequency Response Control Loop Characteristics Autoleveller Perturbation Autoleveller Applications Autoleveller Construction Measurement Delay Transmitter Variable Speed Unit Plattdrawframe Autoleveller Wira Autocount7 Combing Basic Objectives Noil Percentage Tear Combing Cycle Machine Comb Types Fibre Feed Cotton Combing Preparatory Processes Comb General Features Combing Cycle Sliver Delivery Applications Woolcombing Preparatory Processes Comb General Features Combing Cycle Worsted Top Finishing8 Package Formation and Drawing Prior to Spinning False Twist Lap or Roll Delivery Can Delivery Balling Head Delivery Roving Twist Flyer Lead Delivery Bobbin Lead Delivery Drawing Worsted Semi-Worsted Carded Cotton Combed Cotton Flax Jute Spun Silk9 The Spinning Process Classification of Spinning Machines General Features of Conventional Spinning Machines Creels Roving Traverse Top Roller Covering and Pressure Underclearers Spindle Drives Change Speed Devices Speed Limitations Variable Speeds Spindle Pitch Lifter Traverse Productive Efficiency Piecening Automatic Doffing Economics General Features of the Spinning Process Yarn Strength Twist Variation and Yarn Appearance Yarn Thickness, Compressibility and Twist Production End-Breakages Twist Formulae Yarn Length Contraction Fine Count Limit Fly Waste10 Fibre Migration and Displacement Characterization of Migration Factors Influencing Displacement Fibre Yarn Process11 Intermittent Spinning Machines Mule Spinning The Woollen Mule Cycle of Operations Delivery Drafting Twisting Backing-Off Winding-On Centrifugal Spinning12 Conventional Frame Spinning Machines Flyer Spinning Ring Spinning Spindle Arrangement Winding-On Revolutions Twist Variation Calculated Twist Yarn Tension Balloon Theory Balloon Collapse Control Rings Moving Lappets Rings and Travellers Factors Influencing Spinning Conditions Ring Diameter Balloon Height Spindle Speed Traveller Mass Spindle Attachments Condenser Yarn Spinning Automatic Underwinding Cap Spinning13 Open-End Spinning Principles Advantages Basic Methods Vortex Axial Discontinuous Friction Rotor Rotor Spinning Fibre Assembly Twist Insertion and Yarn Withdrawal Rotor Machine Features Opening Methods Fibre Transfer Bridging Fibres Wrapper Fibres Rotor Design Bearings and Drives Technical Aspects Twist and Draft Calculations Theoretical and Calculated Twist Cross-Sectional Number of Fibres Change of Draft and Twist Yarn Structure Cleanliness of Fibre Feed Sliver Preparation Spinning Tension and Fine Count Limit Power Consumption Rotor Speed Rotor Diameter Spinning Twist and End-Breakages General Features of Rotor Machines Economic Aspects Open-End Yarn Uses14 Repco Self-Twist Spinning Principle of Self-Twist Spinning Self-Twist (ST) Yarn Twisted Self-Twist (STT) Yarn Self-Twist Spinning Machine Creel Drafting Zone Twist Insertion Fly Waste Removal Yarn Convergence Guides and Yarn Phasing Yarn Delivery General Features Advantages and Limitations of ST Spinning Self-Twist Yarn Definitions Cycle Length Self-Twist Per Half-Cycle Average Self-Twist Self-Twist Factor Yarn Count Twisted Self-Twist (STT) Yarn Pairing Twist Pairing Twist Factor Pairing Twist/Self-Twist Relationship Added Twist Factor Pairing Twist/Added Twist Relationship Self-Twist Yarn Requirements Recommended Processing Sequence Self-Twist Knitting Yarns High Bulk Acrylics Regular Yarns Developments of Self-Twist Techniques Selfil Wrapped Core Yarns15 Spinning Developments Twistless Yarns Twistless Spinning TNO Systems Pavena System Semi-Molten Polymer-Core Yarns (Bobtex ICS) Axial Fibre Slippage Yarns Jet Spinning Bobtex Abs Spin-Folding Wrap-Spun Yarns The Axifugal System Front Folding Felted Yarns16 Yarn Folding Folded Yarns Cabled Yarns Folding Objectives S on Z Yarns Coating Colour Twists Knitting Balanced Twist Maximum Strength Cotton Yarns Z On Z Yarns Dual Up/Down Folding Folding Routine Folding Machinery Conventional Ring Fancy Yarns Two-Stage Hamel Two-For-One17 Yarn Preparation Parallel-Sided Cheese Angle of Wind Wind and Traverse Ratio Traverse Displacement Precision Winders Constant Spindle Speed Constant Surface Speed Combination Speeds Drum Winders Grooved Drum Finger Traverse Cone Winding Cone Taper Yarn Tensioning Package Stability and Density Yarn Clearing Mechanical Clearers Electronic Clearers Photoelectric Capacitance Knots Splicing Yarn Conditioning Yarn Waxing Free Running Power Driven Emulsion Molten Wax Yarn Length Measurement Automatic Winding Multi-Knotter Machines Traversing Knotter Machines Carousel Machines Yarn Steaming and Storage Yarn Mercerizing and the Prograde Process Yarn Singeing Yarn Sizing Yarn Polishing Yarn Reeling Lea Reeling Cross Reeling Change Reeling Machines Double Reeling Machines Bundling Yarn Balling Hank-to-Cone Winding Pineapple Cones18 Static Electrification and Atmospheric Control Static Formation Dissipation Gaseous Discharge Fibre Conduction Anti-Static Conduction Dissipation for the Consumer Atmospheric Control Side Effects Recommended Processing Conditions Travelling Cleaners19 Yarn Properties Irregularity Drafting Waves Variance-Length Curves Index of Irregularity Correlograms Periodicity Long-Term Count Variation Tensile Properties Individual Thread Tests Hank Tests Constant Tension Winding Tests Ballistic Tests Yarn Breakage Fibre Blends Tenacity and Strength Realization Yarn Initial Modulus Twist Hairiness Thickness and Compressibility Pilling Bending Rigidity ST and STT Yarns Selfil Yarns Twistless Yarns Bobtex ICS Yarn Open-End Yarns Sewing Threads20 Yarn Faults Neps Slubs Spewing Piecenings Married Ends Soft (or Slack) Twist Hard Twist Mixed Lots21 Speciality Yarns Fancy Yarns Condenser-Spun Drawn-and-Spun Spiral Diamond Multifold Gimp Mock Chenille Cloud Knop Loop Snarl Spiral Stripe Slub Eccentric Folded Chenille Core Yarns Coloured Yarns Solid Shades Mixture Shades Gill Mixing Re-Combing Mixing in Drawing Vigoureux (Melange) Printing Imitation Vigoureux Speciality Coloured Yarns Twist Shades Single Marl Marl Half Marl Double Marl Single Mottle22 Tow-To-Sliver Conversion and Bulked Acrylic Yarn Production Comparison of Methods Cutting Converters Crush Cutting Double-Cuts Fused Fibres Fish Food Stretch-Breaking Converters Heater Temperature Stretch Ratio Bulked Acrylic Yarns General Principles Blend Proportions Pre-Relaxation Yarn Shrinkage Acrylic Yarn CountsAppendix: Processing Sequences Woollen Worsted Semi-Worsted Cotton Flax JuteIndex