Water Jet Loom
Water Jet Loom use the same principle as air jet looms, however, they take advantage of pressurized water to propel the weft. The advantage of this type of weaving is that water power is cheaper where water is directly available on site. Picks per minute can reach as high as 1000. A Water Jet is more coherent than an air jet. It does not break up easily, and the propulsive zone is elongated, making it much more effective. It is effective in terms of energy requirements, it is quite and when the jet does break up, it goes into droplets which create very little turbulence to disturb the filling.
The droplets spread in such a way as to wet much of the warp, thus a sized warp containing a water soluble adhesive can be adversely affected.because of this, Water Jet Loom is usually restricted to filament yarn, but there is some hope that it might become economically feasible to weave staple yarns on these looms.
Two main reasons for the efficiency of the Water Jet Loom are that there are no varying lateral forces to cause the filling to contract and the moving element is more massive because it is wet. Thus there is less chance of fault due to contact with the warp.
The range of jet, and thus the width of the looms, depends on the water pressure and the diameter of the jet. Water is virtually incompressible and a simple jerk pump can be used to give adequate pressure with difficulty.
A firmans hose has a tremendous range but the jet is several cm in diameter. Large volumes of water and considerable pumping powers have to be used. In weaving , a much more modest jet is used. In fact, it is possible to reduce the diameter of the jet to some 0.1 cm, and the amount of water used per pick is commonly less than 2c.c. even with these small jets, it is possible to weave at upto 2 meters in width with small power consumptions. It is also possible to weave at upto 1000 picks/min on narrower looms. Several forms of Water Jet Loom have now become established.