The process of producing a fabric by interlacing
warp and weft threads is known as weaving.
The machine used for weaving is known as
weaving machine or loom
The basic purpose of any loom is to hold the
warp threads under tension to facilitate the
interweaving of the weft threads.
The precise shape of the loom and its mechanics
may vary, but the basic function is the same.
Different types of
looms are most often
defined by the way
that the weft, or pick,
is inserted into the
Many advances in
weft insertion have
been made in order
more cost effective.
Water-jet weaving machines were first developed in
Czechoslovakia in the 1950s and Subsequently refined by
the Japanese in the 1960s.
The water jet loom was first shown at the Brussels textile
Machinery Exhibition in 1995.
Water- Jet weaving Machines: These Machines have made
significant appearance in Japan and some European
countries, where more than 60,000 Machines are installed.
How-ever they cannot be called versatile and flexible
• Pick insertion
Rate ( 750 to 900
• Pick insertion
Rate (1000 and
1350 yards per
• Pick insertion
Rate ( 1800 yards
• Pick insertion
Rate ( 2280 M/
Water jet Air jet
A water Jet is the machine for weaveing cloth (loom) which use a Jet of
Water to insert the weft (crosswise threads) into the warp (leghtwise threads)
The force of air water carriers the yarn from one side to the other.
These machines are produced only by few companies and are used for the
manufacture of light and medium weight fabrics with standard characteristics
and in water repellent fibre materials,
Water jet machines are extensively used in East Asia, but have limited
importance in other countries.
They are characterized in particular by high insertion performance and low
In this technique a water jet is shot under force and,
with it, a weft yarn. The force of the water as it is
propelled across the shed carries the yarn to the
opposite side. This machine is economical in its
• A water jet of only 0.1centimeter is sufficient to carry a yarn across a 48 inch
• The amount of water required for each weft yarn is less than 2.0 cubic
• Water-jet machines can reach speeds of 2,000 meters of picks per minute
Figure shows how the machine operate: The weft yarn, which is fed from cone 7, is drawn-off
by a feeding and measuring device 2 and then passes through a tension regulator 3 and a weft
clamp 4. When the insertion has to take place, the weft clamp loosens its hold and the thread
inserted inside a nozzle 1 is struck by a jet of pressurized water and launched through the shed at
high speed. After the insertion has taken place, while the weft is hold flat by the threads which are
moved by the leno mechanisms 5, the thermal knives 14 enter into action on the launch side to cut
the weft, and on the opposite side to trim the fabric. A yarn clamping device 13 holds the weft
waste which is cut off by the right-handed thermal knife, while rotating gears arrange for its
removal (centre selvedge).
The water is conveyed by a pump 8, provided with a filter, the piston of which is controlled by a
cam 10 producing the phases of water suction from the container 9 and of water supply to nozzle 1.
The sequence of the launch phases is the following: the pump 8 enters into action and the initial
water jet serves only to straighten the residual small piece of weft, from nozzle 1 to thermal knife
14. This action, which has a duration time varying from 5 to 30 rotation degrees of the main shaft,
depends on the yarn count and is named guide angle. The yarn flight forms a so-called flight angle,
leaving clamp 4 open to permit to the pressurized water jet to insert the weft thread into the shed.
The clamp opening time varies according to reed width and to loom running speed. On yarn exit
from the shed, there is an electrical feeler or an infrared sensor which checks the presence of the
weft end and makes the machine to stop in case of absence of the weft.
A drying device removes the humidity absorbed by the fabric, sucking it through grooves produced
in the front beam 6 of the machine. A maximum of two weft colours can be inserted (weft mixer).
Water-jet looms are less commonly used than air-jet, but they are preferred
for some types of fabrics.
They are less noisy
Require less space than most other types
Minimal damage to warp yarns during the weaving operation.
As there is no abrasion on warp yarns by the jets of water.
Mostly suitable for filament yarns as the moisture absorption property is
less in filament yarns.
The power consumption for inserting the weft yarn is very less. Hence it
is economical for the industries to use this Water Jet Weaving Machines in
weaving the filament yarns.
Low Drag and Shallow Draught
Smooth and Quiet
Maximum Engine Life
Better fabric quality.
User-friendliness, with easy,
straightforward machine operation
Minimal wear .
● Ease of operation.
● High fabric quality irrespective of
● Pick density alterable while the
machine is in operation.
● Immediate help trouble-shooting
● Self-adjusting stop position of the
They cannot produce as great a variety of fabrics
(no heavy or bulky yarns), nor can they produce
as a wide a fabric (jets have less yarn-carrying
Water-jet looms are best suited only for weaving
filament yarns made of hydrophobic fibers
(water-resistance fiber) like nylon, or
wet fabric cannot be stored in a roll, water jet
looms are equipped with efficient drying units.
Air and Water jet machines can weave fabric at higher
speeds compared to the projectile and rapier looms.
The high power consumption results in higher costs.
The flow of the air is also difficult to control and waste heat
produced by the compressors is sometimes wasted when it
could be used for other operations in the factory. However
cooling of the factories via air Conditioning
Air and water jet looms are save the energy costs in this
The rapier and projectile looms produce a lot more heat
and so air Conditioning is often installed to keep
temperatures down within the factory
From the data's collected we can clearly
understand that the water Jet Weaving has its own
higher production rate and advanced technologies.
The water Jet loom in the recent years playing a
major role in the fabric manufacturing of ( Synthetic
fabrics ) but these Weaving Machines have certain
disadvantages like selvedge problems which is not
yet that much cleared etc