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Volume 5, No.4/2005
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NOVEL APPROACH TO
STUDYING COMPRESSION PROPERTIES IN TEXTILES
Murthyguru
Department of Textile Technology
Indian Institute of Technology
Hauz Khas, New Delhi -110 016
Data analysis of a fabric’s compression properties can only be
done when the limits of compression are known. The best formula is
van Wyk’s, although the meaning of the physical parameter is still
not clear. On the basis of van Wyk’s equation, a study of the
compressibility of woven fabrics can be initiated in partnership
with Pierce, Kemp and Hamilton’s approach for circular yarns and
the flattened yarns of a fabric under pressure. Neural network
models promise to solve the drawbacks of de.Jong’s and other
models. The fit of the pressure-thickness relationship may be
improved by using exponential function and the Iterative method,
such as Marquardt’s algorithm for evaluating compression
properties. Back-propagation promises to give better results,
since the KES-FB3 compression measuring instrument works by
minimising error levels. The optimisation of low-stress mechanical
properties is possible by using trained networks, and this venture
forms an absolute method for comparing the functional properties
of fabrics.
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FRICTORQ, ACCESSING FABRIC
FRICTION WITH A NOVEL FABRIC SURFACE TESTER
Mário Lima1,
Lubos Hes2, Rosa Vasconcelos1, Jorge Martins1
1University of Minho,
Engineering School, Mechanical and Textile Departments,
4800-058 Guimarães, Portugal,
2Technical University of Liberec, Textile Engineering
Dep., Liberec, Czech Republic
A new method to characterise
the coefficient of friction of textile fabrics is proposed. The
principle is based on the dry clutch, where an annular shaped flat
upper body that is kept still, rubs against a lower flat surface,
which rotates around a vertical axis at a constant angular
velocity. Friction coefficient between the two contacting surfaces
is then proportional to the level of the dragging torque between
them, measured by means of a precision reaction torque sensor.
Contact pressure is constant, given by the own weight of the upper
body. The signal from the torque sensor is digitalised through an
electronic interface and fed into a PC where friction coefficient
is worked out. Finally, experimental work is reported.
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INVESTIGATIONS ON THE POSSIBILITY OF OBJECTIVE CHARACTERISATION OF
SAILCLOTH
E. Vujasinovic1,
R. Cunko2, Z. Bezic3
1University of Zagreb, Faculty of Textile Technology,
Zagreb, Croatia
2University of Zagreb, Faculty of Textile Technology,
Zagreb, Croatia
3Victory sailmakers – Intervela d.o.o. Bac pri Materiji,
Materija, Slovenia
Although modern sailcloth
materials are extremely complex, a considerable degree of disorder
is still present in the evaluation of their quality, and
experience is still the most important parameter in assessing a
product. For those reasons, precise characterisation and
evaluation of modern sailcloth is a topic that requires systematic
investigation, both in view of defining relevant characteristics &
parameters, and in defining and adapting adequate testing methods
and procedures & evaluation of results. The paper presented here
is a contribution to the scientific and professional approach to
the topic.
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VOLUME POROSITY AND PERMEABILITY IN DOUBLE-LAYER WOVEN FABRICS
E. A. Elnashar
Faculty of Specific Education,
Kafer ElSheikh,
Tanta University, Egypt
Clothing for
garments is designed to meet both the safety and the comfort of
human beings. Porosity is considered to be one of the basic
features representing a textile structure. The properties of
fabrics were analyzed by determining the efficiency of fabric
porosity. The woven fabric multi-layer structure, the warp and
weft densities, and the type of weave are factors of a woven
fabric, which as porous material enables to transmit air, heat
energy, and liquid perspiration. Several methods considering
thread distributions have been developed to determine the woven
fabric’s porosity. A mathematical model based on an ideal geometry
of the porous structure of a multi-layer woven fabric has been
developed.
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AN APPROACH TO THE ‘proKNIT’ SYSTEM AND ITS VALUE IN THE
PRODUCTION OF WEFT-KNITTED FABRICS
Efthymios Gravas, Paul
Kiekens and Lieva Van Langenhove
Ghent University, Department of
Textiles, Technologiepark 907,
9052 Gent (Zwijnaarde), Belgium
‘ProKNIT’ is the result of a
project based on the consideration that knitted fabrics shrink in
both directions, or that some of them shrink in one direction but
expand in another. This shrinkage and extension is not
proportional; it varies greatly depending on the type of knitted
fabric. However, one value that always changes by increasing upon
fabric shrinkage is the fabric’s weight. Increases in weight from
shrinkage will not only increase the cost of production but may
also affect the final product in a number of ways. Therefore, a
program that would help to avoid problems of this nature could be
created which would predict the weight of the knitted fabrics in
different relaxed conditions, by using appropriate variables such
as knitting machine gauge, yarn count, type of fabric, fabric loop
length, tightness factor and courses & wales per unit length, but
would not be too difficult to operate. This is how ‘proKNIT’ came
about. The first part of the word ‘pro’ derives from the Greek
meaning ‘before’; therefore, the name of the system appropriately
refers to the estimations made before a knitting fabric is
produced.
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STUDIES ON CORN STARCH FILLED POLY (STYRENE-CO-BUTYL ACRYLATE)
LATEX REINFORCED POLYESTER NONWOVEN FABRIC COMPOSITES
M.N. Satheesh Kumar1
and Siddaramaiah2
1Research and
Development Division, Raman Boards Limited, Mysore-570 012, India
2Department of Polymer Science and Technology, Sri
Jayachamarajendra College of Engineering, Mysore-570 006, India
Poly (styrene-co-butyl acrylate)
latex was prepared with a 70:30 weight ratio of styrene to butyl
acrylate. Various weight percentages of cornstarch were
incorporated into the prepared copolymer latex. Polyester nonwoven
fabric reinforced-cornstarch-filled copolymer latex composites
were manufactured by the impregnation method. The pickup ratio of
latex to fabric was maintained at 3.2:1. The composites’ physico-mechanical
properties, percent water absorption and percent thickness
swelling were studied. The manufactured cornstarch-filled
composites were evaluated for their ability to retain their shape
after being moulded to the desired shape by measuring the
percentage area, shape retention, hardness and resilience. It was
observed that the manufactured thermoplastic composite specimens
retained or increased their mechanical properties up to 20 wt%
cornstarch loading.
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ON-LINE TECHNIQUE FOR MEASURING THICKNESS FOR THREE-DIMENSIONAL
BRAIDED COMPOSITE MATERIAL PREFORMS
Zhenkai Wan, Jialu Li
Tianjin Polytechnic University
Tianjin 300160, REPUBLIC OF CHINA
This paper presents an
automatic method that can measure the thickness of
three-dimensional (3-D) braided composite preforms. The thickness
of 3-D braided composite material preform is an important
parameter of 3-D braided composites. With the development of 3-D
braided composite technology, an automated measurement technology
for thickness of braided composite preform has become an
importantgoal. The objective of this paper is to present an
automatic measuring system. The system we devised consisted of a
computer, a proximity sensor, a pressure sensor, an analog-to-digital
converter and pulse motor, etc. The measuring principle and
results are discussed in the paper. The system was tested on both
carbon and glass fibre preforms. We obtained very encouraging
results. Experiments showed the pressure and eddy current
resistance value are important parameters for measuring the
thickness of 3-D braided composite material preforms. The
measuring precision is higher when the pressure value ranges from
0.6kg/cm2 to 0.8kg/cm2 and the eddy current
resistance is 2kW
for preforms made of carbon-fibre than of other substances.
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ADAPTING AND TUNING QUALITY MANAGEMENT IN SPINNING INDUSTRY
Hisham A. Azzam1,
Sayed T. Mohamed2
1Textile Technology Department, Industrial Education
College, Beni-Suef, Egypt
2Faculty of Engineering, Minia University, Minia, Egypt
The Egyptian government has
shown substantial consideration regarding the rehabilitation and
restructuring of inefficient companies in the public sector with
regard to converting them into profitable companies which will be
ready for privatisation. Furthermore, textile manufacturing can be
considered as one of the biggest industries in the public sector.
So, the idea of showing how textile manufacturers in the public
sector can be developed to meet the requirements of marketing and
product strategies has been initiated.
This study has been prepared to assist in developing one
public-sector textile manufacturer to meet the requirements of a
quality management system, which in turn reflects on improving the
mill performance. Applying the technical means of quality
management in the spinning industry, preparing the spinning
industry for quality agreements, requirement profiles for
different yarn quality characteristics and types, spinning quality
problems and solutions, and optimum yarn quality at optimum costs
are the key areas which are covered in a unique manner.
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