BAHIR DAR UNIVERSITY ETHIOPIAN INSTITUTE OF TEXTILE AND FASHION TECHNOLOGY Advanced Woven Fabric Manufacturing Seminar on: Water Jet Loom Name : fekade dejene Submitted to: Prof.Dr.V.R Sampath hard working is the key for success. Contents: Weaving Basic weaving motion Introduction to water jet History Working principle Working conditions Features of water jet loom Merits and Demerits Conclusion hard working is the key for success. 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. hard working is the key for success. 1 Primary motion 2. Secondary motion 3. Auxiliary motion • Shedding mechanism • Picking mechanism • Beat-up mechanism • Let-off motion. • Take-up motion. • • • • • • • Weft accumulator Warp protector mechanism Temples Weft stop motion Warp stop motion Weft selector Selvedge mechanism hard working is the key for success. Cont. Many advances in weft insertion have been made in order to make manufactured cloth more cost effective. Different types of looms are most often defined by the way that the weft, or pick, is inserted into the warp. Based on the weft insertion looms are classified into: ∑ Shuttle loom (conventional) ∑ Shuttle less looms (unconventional) ጓ Rapier ጓ Projectile ጓ Air jet and Water jet hard working is the key for success. A water Jet is the machine for weaving cloth which use a Jet of Water to insert the weft into the warp shed. The force of 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, primarily multi-filament synthetic yarns. hard working is the key for success. Cont.…. A water jet of only 0.1centimeter is sufficient to carry a yarn across a 48 inch shed. The amount of water required for each weft yarn is less than 2.0 cubic centimeters. Water-jet machines can reach speeds of 2,000 meters of picks per minute hard working is the key for success. History •Pick insertion Rate ( 1800 yards per minute)(1975) •Pick insertion Rate (1000 and 1350 yards per minute) (1972) hard working is the key for success. •Pick insertion Rate ( 750 to 900 yards per minute) Parts of the machine Accumulator • Nozzles • Leno devices Tension regulator Measuring devices • Thermal knives • Electric fellers • Sensors • Pump hard working is the key for success. hard working is the key for success. Working principle The hard working is the key for success. above 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. Cont. After hard working is the key for success. 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. Cont. The hard working is the key for success. sequence of the launch phases is : 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. Cont. On hard working is the key for success. 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 colors can be inserted (weft mixer). Technical Parameters : Reed Width : 170, 190, 210, 230CM Filling Insertion Rate : 2280 M/ Minute Max. RPM : 1200 RPM Max. Power : 3.5 KW, 4.6KW Amount of Heald Frame : Weft Density : 5 ~ 60 pick / cm 10pcs max. for Plain Shedding type ; 16pcs max. for Dobby Shedding type hard working is the key for success. hard working is the key for success. hard working is the key for success. hard working is the key for success. Timing diagram The water jet is capable of maintain its concentration and thus its force over a greatest distance than air jet 0⁰ beat up read at forward 10⁰ healed frame opening 90⁰ pump cam jetting start 110⁰ cramper open flying start angle 180⁰ reed at backmost position 225⁰ cramper close flying angle complete 270⁰ held frame level 285⁰ feeler detect weft 355⁰ healed frame closing Difference b/n air jet and water jet Both are same in many ways, but they are differ in construction, operating condition and performance. 1. warp and weft must be water intensive. 2. all the machine parts must be resistance to corrosion. 3. miniature pump are enough to feed water to the nozzle, no compressor are needed 4. some factors are consider while selecting the water E.g. Cont.….. Turbidity ppm Less than 1 PH Hardness ppm Plus ion Minus ion 6.7 to 7.0 Below 0.01 Below 0.03 Below 0.03 conductivity Below 0.03 Cont.…… Turbid water contains organic(plants)and inorganic (salt, rock etc.) Problem of scaling, damaging the pump nozzle and cylinder PH contains hydrogen ion concentration problems of erosion and rusting ,PH must be neutral Hardness in water contain soluble salts of calcium and magnesium Plus ion contain iron and magnesium compounds which give scaling Minus ion contain free chlorine which cause problems of erosion Cont.….. • The conductivity of the water is the main indicator of the efficiency of the demineralization plant. Weft insertion system It depends up on the following factors: Amount of water jetted Pressure under which the water is pumped Cross section of the nozzle The timing of the cramper opening and closing with respect to water jetting angle Measuring length of the yarn Position of the nozzle Kind of yarn used synthetic Filament Polyster & Nylon Taslon hard working is the key for success. Artificia l silk Glass & carbon Features of Water Jet Loom In case of water jet loom, weft yarn package weight varies 3.6 to 4.1 kg. Here, treated water is used by pump nozzle. It consumes less power than others. Higher number of weft insertion in water jet loom than air jet loom (normally 600ppm). hard working is the key for success. Compressed water from Nozzles forms jet. Pick length need to be measured . Left hand side picking only…external package.. Weft measuring device Catch cord warp threads from auxiliary selvedge which is cut off from fabric.. Water collection and drying No relay nozzle or water guides Merits of water jet 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. It is economical for the industries. High Efficiency Low Maintenance Maximum Engine Life Simplicity Easy installation hard working is the key for success. 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 power). Water-jet looms are best suited only for weaving filament yarns made of hydrophobic fibers (water-resistance fiber) like nylon, or polyester/cotton. wet fabric cannot be stored in a roll, water jet looms are equipped with efficient drying units. hard working is the key for success. By using hard water, here may form rust on the yarn. It is not perfect for absorbent fiber such as cotton. About 60 percent of WJL stoppage is caused by poor flying of yarns. hard working is the key for success. 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 way. The rapier and projectile looms produce a lot more heat and so air Conditioning is often installed to keep temperatures down within the factory hard working is the key for success. Conclusion 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. hard working is the key for success. hard working is the key for success. 1. Drying device is attached in the breast beam of the machine 2. discuss the factors that affect the flying stability of the weft during weft is inserted by water jet. 3. hard working is the key for success.
