introduction to weaving,history and weaving preparations

1. Fabric Manufacturing(Weaving)
TE-1051

2. WEAVING:
• Weaving is a process of
interlacing of warp and weft
yarn at right angle to each
other . There are practically an
endless number of ways of
interlacing warp and filling yarns
.Weaving of yarns into a fabric is
performed on a "weaving
machine" which has also been
called a "loom". In practice, the
weaving machines are named
after their filling insertion
systems.

3. History
• Based on the filling insertion systems, the weaving
machines can be classified as shuttle and shuttleless
weaving machines. Shuttle looms have been used for
centuries to make woven fabrics. In this type of loom, a
shuttle, which carries the filling yarn wound on a quill,
is transported from one side to the other and back. In
the mid 20th century, other weaving machines started
to emerge that used other forms of filling insertion
mechanisms such as air, projectile, rapier and water.
In reference to shuttle looms, these machines are
called shuttleless looms or shuttleless weaving
machines. Today, the shuttle looms have become
obsolete and are not manufactured anymore except for
some very special niche markets.
Continued

4. • The existing shuttle looms have been replaced by the
shuttleless weaving machines in industrialized countries.
Nevertheless, approximately 2.6 million of the 3.2 million
looms in existence throughout the world in 1998 were still
shuttle looms . However, they are being replaced by the
shuttleless weaving machines at a fast rate. Today, the three
most popular weaving machines are air-jet, rapier and
projectile machines
“Handbook of Weaving by Sabit Adanur, P-4,6”

5. Insertion medium

6. Flow Chart of Weaving
“Handbook of Weaving by Sabit Adanur, P-4,6”

7. Process involved in weaving
• Winding/Rewinding
– In fabric manufacturing, directly winding is not so much important, but
rewinding is importan,after warping some packages contain just a few
grams of yarn which is unsuitable for the efficiency of further
processing, such as warping, twisting, and quelling. This necessitates
the preparation of a dense and uniform yarn package of sufficiently
large size from unsuitable packages which can unwind in the
subsequent operations without interruptions, is called rewinding.

8. Warping:
• In general terms, warping is transferring many yarns
from a creel of single end packages forming a parallel
sheet of yarns wound onto a beam.

9. Sizing
• The weaving process requires the warp yarn to be strong, smooth and elastic
or extensible to a certain degree. To achieve these properties on warp yarns, a
protective coating of polymeric film forming agent (size) is applied on the
warp yarns prior to weaving; this process is called slashing or sizing.
• The Purposes of sizing :
– To reduce the yarn hairiness that would interfere with the weaving process
– To protect the yarn from yarn-to-yarn and yarn-to-loom abrasion
– To increase the strength of the yarn. To protect the yarn from various yarn-to-
yarn and
yarn-to-loom abrasion.
3) To increase the strength of the yarn

10. Drawing-In
After sizing, the sized warp beam is prepared to be placed on
the weaving machine and for this purpose drawing-in is done.
It is the entering of yarns from a new warp into the weaving
elements of a machine, namely drop wires, heddles and reed,
when starting up a new fabric style.
Drop Wire Healed Wire Reed

11. Tying-in the new warp ends to the depleted warp is done when a new pattern is
not required.
TYING-IN

12. Weaving:
• Weaving is the interlacing of warp and filling yams perpendicular to
each other t form a fabric. Basic mechanisms which are essential for
continuous weaving are:
– Warp let-off
– Shedding
– Filling Insertion
– Beat-up
– Fabric take-up

13. The passage of the warp through a loom

14. In order to interlace warp and weft threads to
produce fabric on any type of weaving machine,
three operations are necessary :
A)Shedding
Separating the warp threads, which run down the fabric into two
to form a tunnel known as the shed
B)Picking
Passing the weft thread, which traverses across the fabric, through
the shed
C)Beating-up
Pushing the newly inserted length of weft, known as the pick, into
the already woven fabric at a point known as the fell

15. Weaving Principles
Weaving means to make cloth
and other objects. Threads or
strands of material are passed
under and over each other.
• WARP:
– The length wise yarns which run
from the back to the front of the
loom, which forms the basic
structure of the fabric and are
called the warp. Warp yarns are
yarns that are parallel to the
selvedge which run through the
length of the fabric
• WEFT/Fill:
– Crosswise yarns that run across
the loom are called the weft /
filling yarns. Weft yarns are yarns
that are perpendicular to the
selvedge which run through the
width of the fabric