Fabric Manufacturing Technology

Weaving and Knitting

K. Thangamani, S. Sundaresan

• Publisher: CRC Press
• Year: 2022
• ISBN:
  9781000553130
• Edition: 1
• Topic: Tecnologia e ingegneria
• Subtopic: Ingegneria industriale

Fabric Manufacturing Technology: Weaving and Knitting gives the reader a brief idea about the processes involved in fabric formation methods, namely weaving and knitting. It includes various mechanisms involved beginning with primitive handlooms to the latest shuttleless looms, and from hand knitting to the ultra-modern electronic knitting machines. Various design aspects involved in producing the different types of woven and knitted fabrics are dealt with comprehensively. The techno-economics of the latest weaving and knitting machines have been described, including applications of woven and knitted fabrics in the medical field, automotive engineering, aeronautical engineering, protective clothing, and more.

Features

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• Covers the principles involved in the numerous operations of weaving and knitting processes

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• Gives a basic understanding of fabric production, quality control and production

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• Provides a summary of the fabric manufacturing process of weaving, knitting and nonwovens

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• Discusses principles of mechanisms, as well as details of present-day machinery, with illustrations

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• Explores the latest developments in knitting production by whole garment (Shima Seiki) and Knit and Wear (Stoll), CAD/CAM production and simulation of woven fabrics

This book is aimed at senior undergraduate students in textile processing and fabric manufacturing.

1 Introduction

DOI: 10.1201/9780367853686-1

1.1 CLOTHING

Clothing is one of the three basic needs of human beings, the other two needs being food and shelter. The production of clothing was carried out in one form or another from the early days of civilization. In olden days, the materials used for clothing production were mainly natural fibres, such as cotton, wool and silk. While cotton is cultivated from the cotton plant, wool is taken from sheep and silk from the silkworm. The cotton and wool fibres themselves cannot be used directly to form fabrics. These have to be converted into an intermediate product, namely yarn, and the yarn is converted into fabrics. The process of converting the yarn into fabric is called weaving, and the equipment used for weaving is called a loom. In earlier days, other than weaving, fabric was also made from yarn by hand knitting using two pins.

Even though clothing is the main application for textile fabrics, nowadays, the uses of textile fabrics are found in every field. Specially manufactured textile fabrics are extensively used in hygiene products in the medical field, environmental protection, transportation, geotextiles, conveyor belts and safety and protective fabrics, among others.

1.2 RAW MATERIALS

Even though natural fibres were available abundantly, synthetic raw materials were developed to augment the properties of natural raw materials for fabric production from the middle of 20th century. Of the synthetic raw materials polyester, nylon and rayon are used extensively for fabric production. The raw materials for textile applications should be in the form of fibres. The fibres will have very large length to width/thickness ratio; only then can they be used for textile application. The textile fibres should have strength, elongation, flexibility, abrasion resistance and moisture absorption for better performance in fabrics.

The fibres used for textile applications are:

Natural fibres: Cotton, linen, jute, hemp, ramie, wool and silk

Synthetic fibres: Polyester, nylon, rayon, spandex, olefin, aramid, acrylic, carbon and glass

1.3 SPINNING

The fibre length of cotton varies from 12mm to 38mm, and the fibre length of wool varies from 50mm to 100mm. The synthetic fibres can be manufactured in required lengths or as filaments form. The process of converting the fibres into yarn is called spinning. Silk is available naturally in filament form, and it does not require spinning. There are two types of spinning mainly used for producing cotton yarn: (1) ring spinning and (2) open-end spinning.

1.3.1 RING SPINNING

Spinning is a process in which the fibre strands are aligned parallel and twisted. The twisting of the strand of fibres increases the friction forces between the fibres and gives strength to the strand to make it a yarn. Twisting the strand is done by a ring and traveller system and this is called ring spinning. Figure 1.1 shows a ring spinning system.

FIGURE 1.1 Ring spinning system.

1.3.2 OPEN-END SPINNING

In open-end spinning, the fibres are fed into the opening roller in the form of a sliver. The opening roller opens the fibres and feeds the fibres in the form of a strand to the rotor which is rotating at very high speed. The rotating rotor gives twist to the strand and the yarn is taken out. Because a rotor is used to give the twist, this is also called rotor spinning. Rotor spinning is suitable to produce course yarns from short fibres. Figure 1.2 shows a rotor spinning system.

FIGURE 1.2 Rotor spinning system.

The fibre arrangement in a stable fibre yarn is shown in Figure 1.3, and a photograph of yarn is shown in Figure 1.4

FIGURE 1.3 Fibre arrangement in yarn.

FIGURE 1.4 Photograph of yarn.

1.4 YARN NUMBERING SYSTEM

Yarn is made from short fibres and the uniformity of the yarn depends on the uniform placement of fibres in its axis. This is not achieved fully. Its diameter varies in its cross section. Moreover measuring the yarn diameter is difficult due to its structure. Therefore, a linear density measurement is used to number the yarn

There are two methods by which yarn is numbered

1. Indirect system
   This is the traditional system that originated from England. In this system length per unit weight is specified. The number of hanks (840 yards) present in 1 pound of yarn is defined as the yarn number or yarn count. Suppose in a particular yarn if 10 hanks (8,400 yards) weighs 1 pound, then the yarn count of that yarn will be 10s Ne. (“Ne” refers to English count.) In the indirect system, the higher the yarn number or count, the finer will be the yarn. For example, 40s Ne yarn will be finer than 20s Ne yarn.
2. Direct system
   In the direct system, the weight per unit length is specified. The weight in grams per 1000 metres of yarn is defined as the yarn count and this count is called tex. For example if 1000 metres of yarn weighs 40 grams, then the yarn count is 40tex. In the direct system, the higher the yarn count number, the courser will be the yarn. For numbering filaments and fibres, another term is used: denier. Denier is defined as the weight in grams of 9000 metres of filament yarn.

2 Fabric Formation Methods

DOI: 10.1201/9780367853686-2

Fabrics are made by assembling yarn or fibres or a combination of both. They are assembled in such a way that due to their inter fibre frictional force, they produce a material that has strength, elongation, flexibility, abrasion resistance and other properties suitable for clothing and other end uses. There are mainly three methods by which fabrics can be produced for major applications. Figure 2.1 shows the fabric formation methods. Each method has its own merits and demerits, and each has its own end uses.

FIGURE 2.1 Fabric formation methods.

The three main fabric formation methods are

1. Weaving,
2. Knitting and
3. Nonwoven.

2.1 WEAVING

Weaving is a process in which two sets of yarns are interlaced to form a fabric. The lengthwise set of yarn is called warp, and the widthwise yarn is called weft. To make fabric, the lengthwi...

Table of contents

• Cover
• Half Title
• Title
• Copyright
• Dedication
• Contents
• Preface
• Authors
• Chapter 1 Introduction
• Chapter 2 Fabric Formation Methods
• Weaving
• Knitting
• Nonwoven
• Index