Spun Yarn Technology

Spun Yarn Technology provides a comprehensive review of the principles of spun yarn technology.

Chapters are devoted to topics on spun yarn technology such as yarn production, properties of yarn, opening and cleaning loose fibers, fiber blending, the process of carding, and roller drafting, doubling, and fiber control. The spinning process, yarn folding, yarn preparation (winding, tensioning, splicing, and steaming and storage), and the kinds of specialty yarn are presented as well.

Textile technologists will find the text very useful.

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 Properties

2 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 Processing

3 Blending and Mixing

Basic Blending Requirements

Blending Systems

Blending Tolerances

Mixing Deficiencies

Limitations of Blending and Mixing

4 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 Carding

5 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 Pressure

6 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 Autocount

7 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 Finishing

8 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 Silk

9 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 Waste

10 Fibre Migration and Displacement

Characterization of Migration

Factors Influencing Displacement

Fibre

Yarn

Process

11 Intermittent Spinning Machines

Mule Spinning

The Woollen Mule Cycle of Operations

Delivery

Drafting

Twisting

Backing-Off

Winding-On

Centrifugal Spinning

12 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 Spinning

13 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 Uses

14 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 Yarns

15 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 Yarns

16 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-One

17 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 Cones

18 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 Cleaners

19 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 Threads

20 Yarn Faults

Neps

Slubs

Spewing

Piecenings

Married Ends

Soft (or Slack) Twist

Hard Twist

Mixed Lots

21 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 Mottle

22 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 Counts

Appendix: Processing Sequences

Woollen

Worsted

Semi-Worsted

Cotton

Flax

Jute

Index