Industrial Water Footprint: Case Study on Textile Industries
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7 Weaving Fabric Manufacture
Woven fabrics are produced by the process of weaving using machinery named looms.
In this process, two different types of yarns known as the warp yarn (placed parallel
to the loom) and the weft yarn (placed perpendicular to the loom) are interlaced
together to produce a fabric. Before the actual weaving process, the setup has to be
prepared that involves warping, sizing, draw-in, and size-in processes. Warping or
beaming is the process of combining yarns from different cones together to form a
sheet where racks of bobbins are set up to hold the thread while it is rolled onto the
warp bar of the loom. Warping is done to preserve the yarn elongation and maintain a
uniform level. Sizing is a process of adding chemicals to reduce the friction between
the yarns that generally result in yarn rupturing. Some of the common chemicals used
are polyvinyl alcohol (PVA), starch, carboxymethyl cellulose (CMC), etc. Once the
setup is completed the interlacing of fabric takes place via shedding, picking, and
beating. Factors such as quality of yarn, looming time, and type of machinery used
to play a major role in producing a good quality fabric.
8 Knitting Fabric Manufacture
Knitting is the process where the yarn is converted into fabric by interloping the loops
present in the yarn. When a loop is drawn through another, loops are formed either in
the vertical (warp knitting) or horizontal (weft knitting) direction. The intermeshing
of loops in the vertical direction is called wales while the same in the horizontal
direction is called a course. In the warp knitting, there are many pieces of yarn and
there are vertical chains, zigzagged together by crossing the cotton yarn. While in
the weft knitting very similar in method to hand knitting with stitches all connected
horizontally. There are two different types of machines used for knitting the yarn to
fabric and they are named as flatbed and circular knitting machines. The usage of
these machinery varies with respect to production and patterning.
9 Fabric Processing Unit
The fabric in its loom state not only contains impurities, including non-uniform warp
size it requires further special treatment to develop into full textile potential. Also, to
make the fabric more attractive, coloring agents, which are known as dyes are added
after the pretreatment processes. Moreover, final alteration is made in the finishing
process to make the fabric into a more commercial product. These processes utilize
high amounts of water for rinsing and washing the fabrics in the intermediate steps
between each operation. The overall process that involves pre-treatments, dyeing,
and finishing is called the fabric or wet processing step.
43
7 Weaving Fabric Manufacture
Woven fabrics are produced by the process of weaving using machinery named looms.
In this process, two different types of yarns known as the warp yarn (placed parallel
to the loom) and the weft yarn (placed perpendicular to the loom) are interlaced
together to produce a fabric. Before the actual weaving process, the setup has to be
prepared that involves warping, sizing, draw-in, and size-in processes. Warping or
beaming is the process of combining yarns from different cones together to form a
sheet where racks of bobbins are set up to hold the thread while it is rolled onto the
warp bar of the loom. Warping is done to preserve the yarn elongation and maintain a
uniform level. Sizing is a process of adding chemicals to reduce the friction between
the yarns that generally result in yarn rupturing. Some of the common chemicals used
are polyvinyl alcohol (PVA), starch, carboxymethyl cellulose (CMC), etc. Once the
setup is completed the interlacing of fabric takes place via shedding, picking, and
beating. Factors such as quality of yarn, looming time, and type of machinery used
to play a major role in producing a good quality fabric.
8 Knitting Fabric Manufacture
Knitting is the process where the yarn is converted into fabric by interloping the loops
present in the yarn. When a loop is drawn through another, loops are formed either in
the vertical (warp knitting) or horizontal (weft knitting) direction. The intermeshing
of loops in the vertical direction is called wales while the same in the horizontal
direction is called a course. In the warp knitting, there are many pieces of yarn and
there are vertical chains, zigzagged together by crossing the cotton yarn. While in
the weft knitting very similar in method to hand knitting with stitches all connected
horizontally. There are two different types of machines used for knitting the yarn to
fabric and they are named as flatbed and circular knitting machines. The usage of
these machinery varies with respect to production and patterning.
9 Fabric Processing Unit
The fabric in its loom state not only contains impurities, including non-uniform warp
size it requires further special treatment to develop into full textile potential. Also, to
make the fabric more attractive, coloring agents, which are known as dyes are added
after the pretreatment processes. Moreover, final alteration is made in the finishing
process to make the fabric into a more commercial product. These processes utilize
high amounts of water for rinsing and washing the fabrics in the intermediate steps
between each operation. The overall process that involves pre-treatments, dyeing,
and finishing is called the fabric or wet processing step.