মঙ্গলবার, ৯ সেপ্টেম্বর, ২০১৪
রবিবার, ১৬ মার্চ, ২০১৪
The Classification and Description on Textile Loom
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Loom
It is still not certain when the weaving process was introduced to human society. It is clear from many historical records that weaving originated long before the time of Jesus Christ. In England the major shift from agriculture to woolen industry came in the 14th century.
Earlier version of power loom was run by two men. After the steam engine and cast iron in early 1800, great attention was paid to increasing productivity of the machine. To help achieve the increase in productivity, William Radeliffe patented a dressing frame in 1803 for sizing and drying the warp threads prior to winding on to a weavers beam.
A loom is a device used to weave cloth. 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.
Evolution of Looms
A loom is a device that causes interlacement two sets of threads, namely, warp and weft threads, to form a fabric. The very first loom in history is the pit loom. Subsequently the handloom was developed and then the power loom. After the advent of power looms, a number of developments have taken place. The very first power looms that had been developed were of the non automatic type. These looms had neither a positive let off device nor warp stop mechanism or a weft
Page |1
Loom
It is still not certain when the weaving process was introduced to human society. It is clear from many historical records that weaving originated long before the time of Jesus Christ. In England the major shift from agriculture to woolen industry came in the 14th century.
Earlier version of power loom was run by two men. After the steam engine and cast iron in early 1800, great attention was paid to increasing productivity of the machine. To help achieve the increase in productivity, William Radeliffe patented a dressing frame in 1803 for sizing and drying the warp threads prior to winding on to a weavers beam.
A loom is a device used to weave cloth. 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.
Evolution of Looms
A loom is a device that causes interlacement two sets of threads, namely, warp and weft threads, to form a fabric. The very first loom in history is the pit loom. Subsequently the handloom was developed and then the power loom. After the advent of power looms, a number of developments have taken place. The very first power looms that had been developed were of the non automatic type. These looms had neither a positive let off device nor warp stop mechanism or a weft
Page |1
Loom
It is still not certain when the weaving process was introduced to human society. It is clear from many historical records that weaving originated long before the time of Jesus Christ. In England the major shift from agriculture to woolen industry came in the 14th century.
Earlier version of power loom was run by two men. After the steam engine and cast iron in early 1800, great attention was paid to increasing productivity of the machine. To help achieve the increase in productivity, William Radeliffe patented a dressing frame in 1803 for sizing and drying the warp threads prior to winding on to a weavers beam.
A loom is a device used to weave cloth. 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.
Evolution of Looms
A loom is a device that causes interlacement two sets of threads, namely, warp and weft threads, to form a fabric. The very first loom in history is the pit loom. Subsequently the handloom was developed and then the power loom. After the advent of power looms, a number of developments have taken place. The very first power looms that had been developed were of the non automatic type. These looms had neither a positive let off device nor warp stop mechanism or a weft
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changing mechanism. This demanded a great deal of attention from the weaver. The semi automatic loom was then developed which incorporated two out of the above three mentioned mechanisms. Then the automatic loom was developed which had all the three essential mechanisms, namely, positive let off device, warp stop mechanism and weft replenishment mechanism. The last century saw the development of shuttle less weaving mechanisms.
Different Parts of a Loom
Different Parts of a Loom
Short Description of Loom is Given Below:
Heald/Heddle: Wire or cords with eyelets that hold warp yarns in a place.
Function:
1. It helps in shed formation. 2. It is useful in identifying broken ends. 3.It determines the order or sequence of the warp threads. 4. It determines the warp thread density in a fabric.
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Heald shaft/Harness: A wood or metal frame that holds the headl/heddles in position in the loom during weaving. It is usually more than one.
Shuttle: This is a vehicle for weft & passes through the divided warp for the interlacement of the warp & weft.
Shuttle box: Compartment of each end of the sley of a shuttle loom used to retain the shuttle between picking motion.
Picker: It is a piece of leather or other metal placed in grooves or on a spindle inside a shuttle box.
Beams: A cylindrical body with end flanges on which a multiple of warp ends is wound in such way to permit the removal of these yarns as a warp sheet.
Front rest: It is a fixed roller placed in front of the loom above the cloth beam & act as a guide for the cloth to wind on to the cloth beam.
Lease rods: The division of warp yarn into one & one, two & two, & so on is termed as lease. The two rods passed between the two successive divisions of warp yarns are called lease rods.
Slay: It is the portion of loom that carries the reed and oscillates between the harness & the fell of the cloth.
Reed: A comb like wire or device used to separate yarns on a loom & to beat up the filling during weaving.
Treadle: The treadle is a paddle or lever under a loom with which a thread is connected by means of cords.
Temple: Roller device on a loom that hold the cloth at a proper width to prevent it from being drawn in too much by the filling.
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Loom Mechanisms
A loom is a device that causes interlacement two sets of threads, namely, warp and weft threads, to form a fabric.
The hand loom was operated by the weaver using his hands to propel the shuttle from one end to another. The weaver used his foot to operate the healds. The production in this type of loom was obviously very less and thus varied from weaver to weaver
The power loom was operated by power. This reduced the strain of the weaver. Considerable automation has taken place which resulted in lesser strain of the operatives and increasing the production and efficiency of the loom. The shuttle less looms are good examples
The tappet, dobby and jacquard are warp patterning mechanisms. Among the shuttle looms, the tappet loom is the simplest. It is suitable for weaving up to 8 heald shafts. The dobby loom is suitable for figuring upto 40 heald shafts and the jacquard is suitable for elaborate designs running to several picks. The advantage of the jacquard mechanism is that it can control individual warp ends and hence has a large figuring capacity.
Primary motions Secondary motions, and Auxiliary motions.
The primary motions can further be divided as shedding, picking and beat up motions. The shedding opens the warp sheet into layers to facilitate passage of shuttle. The picking motion causes the shuttle carrying weft to be propelled from one end of loom to another. The beat up motion lays the previously laid weft to the fell of the cloth.
The secondary motions comprise of take up and let off motions. The take up motion helps to wind the cloth on to the cloth roller and also influences the pick density in the cloth. The let off motion helps to let the warp from the weaver’s beam at an uniform rate thus maintaining the warp tension constant throughout the weaving process.
The auxiliary motions consist of the warp stop motion, weft stop motion and warp protector motion. The warp stop motion is used to stop the loom in the event of warp breakages. This is necessary to prevent fabric defects such as missing ends and floats. The weft stop motion is used to stop the loom in the event of weft exhaustion or weft breakages. This is necessary to prevent missing weft threads called cracks, in the fabric. The warp protector is used to prevent multiple warp thread breakages in the event of shuttle getting trapped in the middle of the warp sheet.
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Classification of loom
A. Hand loom
1. Primitive or vertical loom
2. Pit loom
- Throw shuttle
- Fly shuttle
3. Frame loom
- Throw shuttle
- Fly shuttle
4. Chittaranjan loom
5. Hattersley loom
B. Power Loom
1. Ordinarily power loom
2. Automatic power loom
3 . Modern power loom – Projectile loom – Air jet loom – water jet loom – Rapier loom – Multiphase loom
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A.Handloom
A handloom is a simple machine used for weaving.In a wooden vertical-shaft looms, the heddles are fixed in place in the shaft. The warp threads pass alternately through a heddle, and through a space between the heddles (the shed), so that raising the shaft raises half the threads (those passing through the heddles), and lowering the shaft lowers the same threads—the threads passing through the spaces between the heddles remain in place.
Elements of a foot-treadle floor loom
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A.Handloom
A handloom is a simple machine used for weaving.In a wooden vertical-shaft looms, the heddles are fixed in place in the shaft. The warp threads pass alternately through a heddle, and through a space between the heddles (the shed), so that raising the shaft raises half the threads (those passing through the heddles), and lowering the shaft lowers the same threads—the threads passing through the spaces between the heddles remain in place.
Elements of a foot-treadle floor loom
1. Wood frame
2. Seat for weaver
3. Warp beam- let off
4. Warp threads
5. Back beam or platen 6. Rods – used to make a shed 7. Heddle frame - heald frame - harness
8. Heddle- heald - the eye
9. Shuttle with weft yarn
10.Shed
11.Completed fabric
12.Breast beam
13.Batten with reed comb
14.Batten adjustment
15.Lathe
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A.Handloom
A handloom is a simple machine used for weaving.In a wooden vertical-shaft looms, the heddles are fixed in place in the shaft. The warp threads pass alternately through a heddle, and through a space between the heddles (the shed), so that raising the shaft raises half the threads (those passing through the heddles), and lowering the shaft lowers the same threads—the threads passing through the spaces between the heddles remain in place.
Elements of a foot-treadle floor loom
1. Wood frame
2. Seat for weaver
3. Warp beam- let off
4. Warp threads
5. Back beam or platen 6. Rods – used to make a shed 7. Heddle frame - heald frame - harness
8. Heddle- heald - the eye
9. Shuttle with weft yarn
10.Shed
11.Completed fabric
12.Breast beam
13.Batten with reed comb
14.Batten adjustment
15.Lathe
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VERTICAL LOOM
The vertical loom is permanent and is used in town and villages. The horizontal loom is used by the nomadic tribes because it can easily be taken apart and transported on the backs of pack animals when the tribe moves on. Although weavers of the towns and villages both use the same style of vertical permanent looms, the town looms are usually larger, whether they are in workshops or in someone’s home.
Vertical looms are solidly constructed because they will be used to make many rugs and so are expected to last for a long time. This type of looms consists of two vertical posts connected by two strong cross beams, resulting in a very sturdy frame. The cross beams are adjustable so that the weaving of different sizes of rugs is possible. A workshop loom may be as high as 20 feet (more than 6 metres) and equally wide.
Facing the loom is a narrow bench on which the weavers sit side by side. As the rug progresses, either this bench can be raised until the weavers are almost bumping their heads on the ceiling, or the warp may be slackened so that the completed part of the rug can be wound around the bottom beam and the weavers can then work at a convenient level.
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Pit Loom
Cloth woven in the pit loom was highly prized during the Kandyan period. The weaving technique, unchanged since the middle ages, uses cotton yarn as its main raw material. Geometric patterns and traditional designs are woven using a very colorful palate. Bead spreads, pillow cases, cushion covers, curtains, furnishing materials, bags and ready to wear clothes are among the products made with this beautiful hand looms.
Frame Loom
No dimensions are given since there is no real limit on the size of the loom. The smallest practical size, however, is probably about 30cm in either direction. While it is possible to build looms smaller than 30cm, it is not practical because weaving narrower than 30cm can be done on the 30cm framework. Therefore, loom size can vary from one made small enough to hold in the lap (30 by 60cm is a good size) or large enough to weave a room size rug. Such large-size looms must be worked by several weavers at one time.
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Hetersley
Richard Hattersley the founder of the company served his apprenticeship at Kirkstall Forge. He set up his own business in 1789 at Stubbings Mill, Airworth, manufacturing nuts, bolts, screws and small parts for textile machines. Richard's son George came into the business and took over its running. In 1834 he was asked to build a power loom for weavingworsted cloth which previously had only been woven on handlooms The first loom was produced in 1834, it was never delivered as it was smashed up in transit by a group ofhandloom weavers of the Luddite persuasion fearful for their livelihood.[1] The replacement was delivered. Hattersley's prospered developing an extensive catalogue, adding new products to their range which included as tobacco machines and garden furniture. Hattersley's continued to prosper with the number of employees peaking to around 1100 just prior to the First World War. They also ventured into production and the subsidiary companies have survived where the parent did not. It closed in 1983.
Hattersley produced a huge range of types of looms over 120 years for all sectors of the market, from the narrow band looms to sheeting looms, have about 26 basic models in their catalogue at one time.
Hattersley Dobby Loom In 1867 George Hattersley and Sons created a loom with a dobby head. A dobby a mechanical heald lifting device which allowed weaving of much more intricate patterns on any looms to which it was fitted.
Hattersley Narrow Fabric Loom In 1908 Hattersley developed the world's first smallware (or narrow fabric) loom, these were suitable for weaving wicks for oil lamps, and the webbing that is used in the automotive industry. To demonstrate this loom, the firm bought the Cabbage Mills and later the Greegate Shed in Keighley where they started production of these products. The firm survives today as Hattersley Aladdin Ltd.
Hattersley Standard Loom In 1921 the Hattersley Standard Loom, designed and built by the company, was to sell in its thousands, bringing considerable financial success to the company.After the recapitalisation boom of 1919 cotton yarn production peaked in 1926, a further investment was sparse. Rayon, artificial silk, was invented in the 1930s inSilsden nearby, and the Hattersley Silk Loom was adapted to weave this new fabric.
Hattersley Domestic Loom The Hattersley Domestic Loom was part of the Hattersley Domestic System that include other machines such as pirn winder and warping mill. It was a compact machine, combing all the know how and precision engineering of the nineteenth century with the need for a treadle operated loom. This looms has tappets to control up to 8 shafts, healds or boards; most simply have 4 shafts and a set of four 2/2 Twill tappets and four plain weave tappets. 5,6,7,and 8 pick tappets were available. In order to cope with the different gearings the tappet drive cog on the bottom drive shaft could be adjusted and there are two sizes of tapped mounting drive cogs. There was also a Dobby version.
The first thirty Hattersley's were sent to the Outer Hebrides in 1919. These were 36 inches in the reed space and single shuttle. In 1924 the first six shuttle, 40 inch reed space looms arrived in Stornoway and this type of loom was the most commonly used loom in the islands' Harris Tweed Industry.
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B.Power loom
Automatic looms or conventional automatic looms
To get high productivity and good quality of fabric, additional mechanisms are added to ordinary non-automatic power looms. These looms are becoming popular because of their advantages of versatility and relative cheapness. Examples :
1. Pirn changing automatic loom
2. shuttle changing automatic loom.
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B.Power loom
Automatic looms or conventional automatic looms
To get high productivity and good quality of fabric, additional mechanisms are added to ordinary non-automatic power looms. These looms are becoming popular because of their advantages of versatility and relative cheapness. Examples :
1. Pirn changing automatic loom
2. shuttle changing automatic loom.
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B.Power loom
Automatic looms or conventional automatic looms
To get high productivity and good quality of fabric, additional mechanisms are added to ordinary non-automatic power looms. These looms are becoming popular because of their advantages of versatility and relative cheapness. Examples :
1. Pirn changing automatic loom
2. shuttle changing automatic loom.
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Projectile Loom:
Sulzer brothers, Winterthur, Switzerland, Who are pioneer in the field of projectile method of weft insertion, have been able to convert a brilliant concept Roshman into a viable commercial weaving machine. It is introduced in the market in 1953.The main feature of this machine is weft insertion system. A bullet like shuttle 90 mm long & weighting about 40 g, technically named as gripper projectile is used here to insert the weft thread into the warp threads.
Figure: Projectile loom Conventional Loom Versus Projectile Loom:
Sulzer projectile weaving machine differs from a conventional automatic loom mainly in two respects.
1. The method of insertion of weft into the warp shed 2. The method of moving the reed and the projectile track
Main Features of Projectile Loom:
1. The picking are projectile receiving units are separated from the moving sley. The sley carries the reed & gripper guides. 2. The gripper projectile made of fine steel, 90 mm long 14mm wide and 6 mm thickness weight is 40 g. It carries the weft thread into the warp shed. 3. The weft is drawn directly from a large stationary cross wound package. There is no weft winding. 4. The gripper projectile is picked across the warp shed at a very high speed ,the picking energy being derived from the energy stored in a metal torsion bar which is twisted at predetermined amount of released to give the projectile a high rate of acceleration .
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5. Picking always takes place from one side, but several projectiles are employed and all of them return to the picking side by a conveyor chain located underneath the warp shed. 6. During its flight through the shed the projectile runs in a rake likes steel guides, so that the warp threads are touched neither by the projectile nor weft thread. 7. Every pick is cut off at the picking side near the selvedge after weft insertion, leaving a length about 15 mm from the edge. Similar length of weft also projects from the selvedge on the receiving side. 8. The ends of weft thread projecting on both sides of the cloth are tucked into the next shed by means of special tucking device and woven in with next pick, thus providing firm selvedges. 9. The reed is not reciprocated as in a shuttle loom, but rocked about its axis by a pair of cams. 10. The reed & projectile guides are stationary during pick insertion. 11. The sley which carries the reed & projectile guides is moved forward & backward through a saddle carrying two follower bowls, which bear against the surface of two matched cams. 12. A sley dwell of 25 degree at back center enables the projectile to travel through the warp shed without being unnecessary reciprocated by the sley. 13. Whenever the reed width is reduced for weaving a small width cloth from the standard reed width, the projectile receiving unit is moved inward on the telescope shaft, to the new selvedge position, and so the projectile travel distance is reduced. 14. Smaller shed opening because of the smaller size projectile. This might result in lower warp breakage rate. 15. Weft insertion rate up to 900-1500 m/min is possible depending up to the width of the weaving machine. 16. The color changing mechanism is less complicated. 17. In case of weft breakage the take up beam & heald frames can de driven in reverse by a pick finding mechanism.
Advantages of Projectile Loom as a Modern Loom:
1. Two or three cloths can be woven simultaneously.
2. It is possible to achieve weaving performances with breakage rate per square meter of cloth. 50% of the number of breaks that would occur on a conventional loom.
3. The lower warp breakage rate in a projectile weaving machine may be due to:
Smaller warp shed Reed with higher ratio of air to wire (70:30) Beat up line being nearer to the centre of the reed between the two baulks.
Smaller warp shed will reduce the warp threads tension to some extent. However care should be taken to maintain uniform tension to ensure that the warp shed is of same depth from one end to another. Otherwise a few slack warp threads at the top shed will result in stitching and end cut of the projectile.
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4. Since the projectile is passing through guides there is no reed to projectile or projectile to yarn contact.
5. With the introduction of four/six colors weaving machine all the mechanical problems of the conventional pick & pick multicolored loom are eliminated.
Rapier Loom:
Insertion of weft by rapier is a mechanically modern & refined version of the primitive method of fabric production in which the weft was secured in a slot of a stick. At present version of the gripper head which are attached to rapiers which are flexible tapes or rigid rods. Mr. John Gabler can be regarded as the father of modern rapier technology he has built a rapier device on a cotton weaving machine in 1922.
Scope of Rapier:.
Single rapier loom can insert weft only on alternate rapier traverse. In many cases this is modified to achieve a higher rapier velocity in the early and late parts of the movement and thus a over maximum velocity halfway through the movement. Due to high rate of insertion the possibility of yarn breakages rate may increase. Additionally, it is necessary to control the weft by passing it trough an effective tension arrangement so that the weaving tension will be more uniform, this can also occurred weft break.
Features of Rapier Loom:
1. An useful feature of rigid rapiers is that they can be simultaneously inserted in two sheds one above the other, for producing double plush and certain carpets. 2. Rapier loom may have various types according to the weft insertion mechanism & number of pick such as insertion of double pick, insertion of single pick, two phase rapier etc. 3. In all rapier looms to-and-fro-movement of the rapiers is derived initially either from a linkage mechanism or from a cam. The use of linkage mechanism has the advantages of simplicity reliability & is cheap, quite and consumers less energy than a cam mechanism but it does not provide any dwell to the rapiers. 4. The only two phase rapier in commercial operation is the saurer of width 2 x 185 cm or 2 x 220 cm having weft insertion rate is about 1200 mpm. 5. The rigid rapier is driven from the centre and has a rapier head at each end.In one cycle of 360 degree the rapier inserts one pick alternately in the right hand and the left hand fabrics, the picks being inserted and beaten up in opposite phase . 6. In gabler system of weft insertion the rapier system is combined with air jet picking system.
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7. Gabler system rapier may be single sided or double sided. The machine include on gabler system Draper DSL,Gusken etc.Those operating on dewas system include dornier, picanol, Novo pignon SACM, Gunne, Smit, Sommet, Sulzer-Ruti etc.
Rapier Loom Integrating the features of rapier looms of Model SJ758 and other imported and domestic rapier looms, Model SJ736-III rapier loom is specially designed for weaving of light, medium and heavy fabrics and check designs, it adopts automatic pick finder and electronic color selector.
Control panel:
The loom is controlled by the control panel with a micro-computer, the lcd display provides a very user-friendly human-machine interface, which shows the production statistic data of each shift and provides the weft color programming function.
Weft color selection:
The machine adopts electronic color selector up to 8 colors, and the color selection pattern is programmed directly on the machine control panel
Wefting: Wefting mechanism adopts 6-lever wefting structure and can ensure the adjustment of the rapier entry and exit time and ensure stable wefting and insertion motion. This machine adopts 4 levers, short connectors and short sley to complete the beating motion, the rock shaft adopts 110mm(diameter) seamless tube to ensure the beating strength and can be suitable for high-speed motion and weaving of heavy and high density fabrics. The rapier transmission box adopts the advanced helix umbrella gears to ensure stable transmission. The tension device adopts 3-rear- beam tension structure, which is specially designed for balancing the warp tension of high- density weaving and can improve the quality of the weaving fabrics.
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Pick finding mechanism:
The machine adopts electronic let-off mechanism with a high-accuracy step motor and the optimized mechanical take-up system for stable and accurate pick finding motion. The pick finding motion is very stable and proved to be very successful and reliable.
The adoption of two pressing rollers on the fabric winding roller enables the worker to unload the fabric from the fabric roller without stop. The frequent adoption of bearings for the major moving parts provides better performance and easier maintenance.
Advantages of Rapier Loom: Over Conventional Loom:
1. The rapier loom doesn’t require dynamic forces or anything like the magnitude as those involved in the conventional loom. 2. The weft insertion rate in a rapier loom is very much influenced by the method of weft control. 3. Weft insertion rate is very high rather than any conventional loom 4. It can occur double pick at a time by double picking insertion system. Here is no need to cut the weft selvedges and no weft wastage. 5. Weft insertion rate is very high rather than any conventional loom Rigid rapiers has a useful features that they can be simultaneously inserted in two sheds one above the other ,for producing double plush and certain carpets. 6. Looms that use rigid rapiers eliminate entirely the need to assist the rapier head through the warp shed, this is a un doubted advantages.
Air Jet Loom:
Weft insertion by means of air jet has made a major breakthrough in the early 70s and its importance is increasing further because of its ability to weave a wide range of fabrics at a very high speed weft insertion rate of about 2000 mpm. The first attempt to use a compressed air steam instead of shuttle is made by Brooks in 1914.
Scope of Air Jet Loom:
To insert the weft threads here used compressed air. Not suitable for the coarser count or heavier fabric. The timing of jet activity should be controlled in such a way that the main nozzle is supplied with compressed air from the beginning of the weft insertion phase and the relay nozzles also receive compressed air. High maintenances is needed.
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Features of Air Jet Loom:
1. Air jet weaving machine is high speed machine having good quality 2. For instance on a weaving machine having a speed of 600 rpm the weaving cycle is 100m/s. 3. Cam control valves have the advantages of high speed precision of action whilst the electrically controlled solenoid valves permit easy setting. 4. Finer count of yarn is used as the weft thread to produce fency type of fabric.
Figure: Air jet loom Advantages of Air Jet Loom Over Conventional Loom:
The conventional loom requires shuttle or shuttle like substance to insert the weft yarn, comparatively in air jet loom there is no need to any kind of shuttle instead of shuttle here the compressed air force is used. In the conventional loom the pick insertion rate is very low compare to the air jet loom. The weft stop motion is machine controlled over the differ from conventional loom In conventional loom the mechanical or hand shuttle reach the weft thread to the fell of the cloth, but in air jet through air force this is done, here uniform let up, take up, uniform picking, uniform bet up is possible. It has the automatic weft repair device.
Disadvantages:
Short or buckle pick Loose pick Snarling Excess dynamic pressure Weft stop problem Tip problem
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Timing of shed may not be proper Too high or too low main nozzle pressure Left side warp yarn is loose.
Water Jet Loom:
The first loom to make use of a water jet for insertion of weft was developed by Satyr.The loom was first shown at the Brussels textile Machinery Exhibition in 1995.
Scope of Water Jet Loom:
Weft and warp yarn must be insensitive .i.e hydrophobic in nature. Weaving of the water attractive fabric is not possible by the water jet loom, Thermoplastic yarns offer the advantages of severance of weft by a heated blade and the provision of a heat selvedge by fusing. It has required miniature pump to feed water under pressure to the nozzle.
Figure: Water Jet loom.
Features of Water Jet:
The water jet loom demonstrated at ITMA ASIA 2005 as a concept model now has debuted as the “ZW8100.” The new model “ZW8100” inherited the basic abilities of the “ZW series” that has enjoyed an excellent reputation as the global standard water jet loom and has enhanced stability at high speed. The ZW8100 intends to succeed and advance the long-cultivated basic abilities of water jet looms – weaving technology, high- speed ability, quality, and energy-saving – for the next hundred years.
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Tsudakoma consistently emphasises the basic abilities: high speed, quality, versatility, eco- friendliness. Tsudakoma particularly focuses on ultra high speed ability - the mission of all jet looms. Because it considers ultra high speed as the base, Tsudakoma has optimised the frame structure, the beating system and the shedding system, and employs a newly-developed nozzle. A navigation system that enjoys a good reputation for air jet looms is also employed while taking careful note on higher versatility and better operability. To give the best answer to reply to market demands, fulfilling basic abilities is indispensable. Flexibility to woven material is also increased. True user-friendliness is attained.
The ZAX9100 is well-established for its ultra-high speed ability. The “ZAX9100HD” is a package model that can weave heavy fabrics at high speed while keeping quality high with enhanced basic abilities and new technology. Tsudakoma’s unique heavy-duty structure responds to user’s strict quality demands. The exhibit demonstrated weaving quality yarn-dyed shirting at high speed.
The ZAX9100 is ranked as a premium air jet loom provided with the “Weave Navigation System.” It handles diverse responsibilities, such as being cost-competitive, quick style change, value-added fabrics, and developing new fabrics that will be required more than ever. The ESS Electronic Shedding System, 6-colour weft selection, and the PSC support weaving value-added fabrics of various kinds and thickness wefts. The PSC Programmable Speed Control controls the rpm per one pick according to weft kinds and fabric weaves in order to attain stable weaving, thus the operation efficiency is considerably increased. Fabrics formerly limited to rapier looms are woven easily keeping quality.
Tsudakoma has the largest air jet terry weaving experience in the world. Many terry weavers consider Tsudakoma’s air jet looms the standard. While fusing the ultra-high speed ability of the ZAX9100 with its abundant terry weaving know-how, various elaborately designed towels such as pileheight changes and pile-cycle switching between 3 to 7-picks can be woven with a pleasant texture. In combination with the electronic Jacquard motion higher value-added terry cloth can be woven.
The “Versa-Terry System” is the integration of Tsudakoma’s terry weaving technology. Various systems that Tsudakoma developed especially for terry are enhanced and new technology for weaving diversified terry cloth designs is employed. The “Versa-Terry System” inherits and advances the thorough experience of the world’s largest record of air-jet terry weaving machines. Improving all of its basic abilities: speed, versatility, quality, energy saving, operability, the ZAX9100-Terry realizes true user-friendliness.
Water Jet Loom Advantages:
Water jet propulsion has many advantages over other forms of marine propulsion, such as stern drives, outboard motors, shafted propellers and surface drives. These advantages include...
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Excellent Maneuverability
Precise steering control at all boat speeds "Zero Speed" steering effect provides 360° thrusting ability for docking and holding stationary. Sideways movement possible with multiple jet installations. High efficiency astern thrust with "power-braking" ability at speed
High Efficiency
Propulsive coefficients as good or higher than the best propeller systems achievable at medium to high planning speeds Flexibility when using multiple water jets may allow operators to continue to operate efficiently on fewer drives
Low Drag and Shallow Draught
Absence of underwater appendages reduces hull resistance Shallow draught - the water jet intake is flush with hull bottom to allow access to shallow water areas and beach landings with no risk of damage to the drive
Low Maintenance
No protruding propulsion gear eliminates impact damage or snags Minimum downtime and simple maintenance routines
Smooth and Quiet
No hull vibration, no torque effect and no high speed cavitations gives maximum comfort levels on board Low underwater acoustic signature
Total Safety
No exposed propeller for complete safety around people in the water and marine life
Maximum Engine Life
Jet unit impeller is finely matched to engine power Power absorption is the same regardless of boat speed No possibility of engine overload under any conditions
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Simplicity
Single packaged module No heavy and expensive gearbox required for many installations. Simple driveline from engine to jet coupling
Easy installation
Complete factory tested package, ready to bolt in No difficult engine alignment problems.
Multiphase Loom:
The phase number of a loom is defined as the average number of shuttles or weft carriers inserting weft simultaneously. It is shown that existing multi-phase looms must have high phase numbers to compensate for their low shuttle velocity. The analysis suggests that looms with high-velocity flying shuttles would achieve equally high weft-insertion rates with moderate increases in the phase number. Such moderate increases in the phase number can be obtained by dividing the shedding and beat-up motions into a comparatively small number of sections. The suggested alternative would avoid many of the textile and engineering problems arising in existing multi-phase looms.
Figure: Multiphase loom
Features of Multiphase Loom:
1. A multi-phase loom with magnetic shuttle features that the spiral reed blade with shuttle path is used for beating-up. 2. The linear motor is used for wefting, the heald wheel or electromagnetically excited heald needle is used for opening, and the weft opening with off-line multi-path asynchronous weft replenishing is used. 3. Its advantages include high efficiency, high speed and low weaving cost.
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4. The multiphase loom can form many different sheds at different places, thereby enabling insertion of number of filling yarns, one behind the other.
Advantages of Multiphase Loom Over Conventional Loom:
1. An analysis of the factors determining the weft-insertion rate of weaving machines shows that these factors are essentially the same on all looms in which shuttles or weft carriers are used, such as conventional shuttle looms, gripper- shuttle looms, and multi-phase looms. 2. Its advantages include high efficiency, high speed and low weaving cost. 3. The multiphase loom can form many different sheds at different places, thereby enabling insertion of number of filling yarns, one behind the other.
Loom
It is still not certain when the weaving process was introduced to human society. It is clear from many historical records that weaving originated long before the time of Jesus Christ. In England the major shift from agriculture to woolen industry came in the 14th century.
Earlier version of power loom was run by two men. After the steam engine and cast iron in early 1800, great attention was paid to increasing productivity of the machine. To help achieve the increase in productivity, William Radeliffe patented a dressing frame in 1803 for sizing and drying the warp threads prior to winding on to a weavers beam.
A loom is a device used to weave cloth. 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.
Evolution of Looms
A loom is a device that causes interlacement two sets of threads, namely, warp and weft threads, to form a fabric. The very first loom in history is the pit loom. Subsequently the handloom was developed and then the power loom. After the advent of power looms, a number of developments have taken place. The very first power looms that had been developed were of the non automatic type. These looms had neither a positive let off device nor warp stop mechanism or a weft
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Loom
It is still not certain when the weaving process was introduced to human society. It is clear from many historical records that weaving originated long before the time of Jesus Christ. In England the major shift from agriculture to woolen industry came in the 14th century.
Earlier version of power loom was run by two men. After the steam engine and cast iron in early 1800, great attention was paid to increasing productivity of the machine. To help achieve the increase in productivity, William Radeliffe patented a dressing frame in 1803 for sizing and drying the warp threads prior to winding on to a weavers beam.
A loom is a device used to weave cloth. 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.
Evolution of Looms
A loom is a device that causes interlacement two sets of threads, namely, warp and weft threads, to form a fabric. The very first loom in history is the pit loom. Subsequently the handloom was developed and then the power loom. After the advent of power looms, a number of developments have taken place. The very first power looms that had been developed were of the non automatic type. These looms had neither a positive let off device nor warp stop mechanism or a weft
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Loom
It is still not certain when the weaving process was introduced to human society. It is clear from many historical records that weaving originated long before the time of Jesus Christ. In England the major shift from agriculture to woolen industry came in the 14th century.
Earlier version of power loom was run by two men. After the steam engine and cast iron in early 1800, great attention was paid to increasing productivity of the machine. To help achieve the increase in productivity, William Radeliffe patented a dressing frame in 1803 for sizing and drying the warp threads prior to winding on to a weavers beam.
A loom is a device used to weave cloth. 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.
Evolution of Looms
A loom is a device that causes interlacement two sets of threads, namely, warp and weft threads, to form a fabric. The very first loom in history is the pit loom. Subsequently the handloom was developed and then the power loom. After the advent of power looms, a number of developments have taken place. The very first power looms that had been developed were of the non automatic type. These looms had neither a positive let off device nor warp stop mechanism or a weft
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changing mechanism. This demanded a great deal of attention from the weaver. The semi automatic loom was then developed which incorporated two out of the above three mentioned mechanisms. Then the automatic loom was developed which had all the three essential mechanisms, namely, positive let off device, warp stop mechanism and weft replenishment mechanism. The last century saw the development of shuttle less weaving mechanisms.
Different Parts of a Loom
Different Parts of a Loom
Short Description of Loom is Given Below:
Heald/Heddle: Wire or cords with eyelets that hold warp yarns in a place.
Function:
1. It helps in shed formation. 2. It is useful in identifying broken ends. 3.It determines the order or sequence of the warp threads. 4. It determines the warp thread density in a fabric.
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Heald shaft/Harness: A wood or metal frame that holds the headl/heddles in position in the loom during weaving. It is usually more than one.
Shuttle: This is a vehicle for weft & passes through the divided warp for the interlacement of the warp & weft.
Shuttle box: Compartment of each end of the sley of a shuttle loom used to retain the shuttle between picking motion.
Picker: It is a piece of leather or other metal placed in grooves or on a spindle inside a shuttle box.
Beams: A cylindrical body with end flanges on which a multiple of warp ends is wound in such way to permit the removal of these yarns as a warp sheet.
Front rest: It is a fixed roller placed in front of the loom above the cloth beam & act as a guide for the cloth to wind on to the cloth beam.
Lease rods: The division of warp yarn into one & one, two & two, & so on is termed as lease. The two rods passed between the two successive divisions of warp yarns are called lease rods.
Slay: It is the portion of loom that carries the reed and oscillates between the harness & the fell of the cloth.
Reed: A comb like wire or device used to separate yarns on a loom & to beat up the filling during weaving.
Treadle: The treadle is a paddle or lever under a loom with which a thread is connected by means of cords.
Temple: Roller device on a loom that hold the cloth at a proper width to prevent it from being drawn in too much by the filling.
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Loom Mechanisms
A loom is a device that causes interlacement two sets of threads, namely, warp and weft threads, to form a fabric.
The hand loom was operated by the weaver using his hands to propel the shuttle from one end to another. The weaver used his foot to operate the healds. The production in this type of loom was obviously very less and thus varied from weaver to weaver
The power loom was operated by power. This reduced the strain of the weaver. Considerable automation has taken place which resulted in lesser strain of the operatives and increasing the production and efficiency of the loom. The shuttle less looms are good examples
The tappet, dobby and jacquard are warp patterning mechanisms. Among the shuttle looms, the tappet loom is the simplest. It is suitable for weaving up to 8 heald shafts. The dobby loom is suitable for figuring upto 40 heald shafts and the jacquard is suitable for elaborate designs running to several picks. The advantage of the jacquard mechanism is that it can control individual warp ends and hence has a large figuring capacity.
Primary motions Secondary motions, and Auxiliary motions.
The primary motions can further be divided as shedding, picking and beat up motions. The shedding opens the warp sheet into layers to facilitate passage of shuttle. The picking motion causes the shuttle carrying weft to be propelled from one end of loom to another. The beat up motion lays the previously laid weft to the fell of the cloth.
The secondary motions comprise of take up and let off motions. The take up motion helps to wind the cloth on to the cloth roller and also influences the pick density in the cloth. The let off motion helps to let the warp from the weaver’s beam at an uniform rate thus maintaining the warp tension constant throughout the weaving process.
The auxiliary motions consist of the warp stop motion, weft stop motion and warp protector motion. The warp stop motion is used to stop the loom in the event of warp breakages. This is necessary to prevent fabric defects such as missing ends and floats. The weft stop motion is used to stop the loom in the event of weft exhaustion or weft breakages. This is necessary to prevent missing weft threads called cracks, in the fabric. The warp protector is used to prevent multiple warp thread breakages in the event of shuttle getting trapped in the middle of the warp sheet.
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Classification of loom
A. Hand loom
1. Primitive or vertical loom
2. Pit loom
- Throw shuttle
- Fly shuttle
3. Frame loom
- Throw shuttle
- Fly shuttle
4. Chittaranjan loom
5. Hattersley loom
B. Power Loom
1. Ordinarily power loom
2. Automatic power loom
3 . Modern power loom – Projectile loom – Air jet loom – water jet loom – Rapier loom – Multiphase loom
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A.Handloom
A handloom is a simple machine used for weaving.In a wooden vertical-shaft looms, the heddles are fixed in place in the shaft. The warp threads pass alternately through a heddle, and through a space between the heddles (the shed), so that raising the shaft raises half the threads (those passing through the heddles), and lowering the shaft lowers the same threads—the threads passing through the spaces between the heddles remain in place.
Elements of a foot-treadle floor loom
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A.Handloom
A handloom is a simple machine used for weaving.In a wooden vertical-shaft looms, the heddles are fixed in place in the shaft. The warp threads pass alternately through a heddle, and through a space between the heddles (the shed), so that raising the shaft raises half the threads (those passing through the heddles), and lowering the shaft lowers the same threads—the threads passing through the spaces between the heddles remain in place.
Elements of a foot-treadle floor loom
1. Wood frame
2. Seat for weaver
3. Warp beam- let off
4. Warp threads
5. Back beam or platen 6. Rods – used to make a shed 7. Heddle frame - heald frame - harness
8. Heddle- heald - the eye
9. Shuttle with weft yarn
10.Shed
11.Completed fabric
12.Breast beam
13.Batten with reed comb
14.Batten adjustment
15.Lathe
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A.Handloom
A handloom is a simple machine used for weaving.In a wooden vertical-shaft looms, the heddles are fixed in place in the shaft. The warp threads pass alternately through a heddle, and through a space between the heddles (the shed), so that raising the shaft raises half the threads (those passing through the heddles), and lowering the shaft lowers the same threads—the threads passing through the spaces between the heddles remain in place.
Elements of a foot-treadle floor loom
1. Wood frame
2. Seat for weaver
3. Warp beam- let off
4. Warp threads
5. Back beam or platen 6. Rods – used to make a shed 7. Heddle frame - heald frame - harness
8. Heddle- heald - the eye
9. Shuttle with weft yarn
10.Shed
11.Completed fabric
12.Breast beam
13.Batten with reed comb
14.Batten adjustment
15.Lathe
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VERTICAL LOOM
The vertical loom is permanent and is used in town and villages. The horizontal loom is used by the nomadic tribes because it can easily be taken apart and transported on the backs of pack animals when the tribe moves on. Although weavers of the towns and villages both use the same style of vertical permanent looms, the town looms are usually larger, whether they are in workshops or in someone’s home.
Vertical looms are solidly constructed because they will be used to make many rugs and so are expected to last for a long time. This type of looms consists of two vertical posts connected by two strong cross beams, resulting in a very sturdy frame. The cross beams are adjustable so that the weaving of different sizes of rugs is possible. A workshop loom may be as high as 20 feet (more than 6 metres) and equally wide.
Facing the loom is a narrow bench on which the weavers sit side by side. As the rug progresses, either this bench can be raised until the weavers are almost bumping their heads on the ceiling, or the warp may be slackened so that the completed part of the rug can be wound around the bottom beam and the weavers can then work at a convenient level.
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Pit Loom
Cloth woven in the pit loom was highly prized during the Kandyan period. The weaving technique, unchanged since the middle ages, uses cotton yarn as its main raw material. Geometric patterns and traditional designs are woven using a very colorful palate. Bead spreads, pillow cases, cushion covers, curtains, furnishing materials, bags and ready to wear clothes are among the products made with this beautiful hand looms.
Frame Loom
No dimensions are given since there is no real limit on the size of the loom. The smallest practical size, however, is probably about 30cm in either direction. While it is possible to build looms smaller than 30cm, it is not practical because weaving narrower than 30cm can be done on the 30cm framework. Therefore, loom size can vary from one made small enough to hold in the lap (30 by 60cm is a good size) or large enough to weave a room size rug. Such large-size looms must be worked by several weavers at one time.
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Hetersley
Richard Hattersley the founder of the company served his apprenticeship at Kirkstall Forge. He set up his own business in 1789 at Stubbings Mill, Airworth, manufacturing nuts, bolts, screws and small parts for textile machines. Richard's son George came into the business and took over its running. In 1834 he was asked to build a power loom for weavingworsted cloth which previously had only been woven on handlooms The first loom was produced in 1834, it was never delivered as it was smashed up in transit by a group ofhandloom weavers of the Luddite persuasion fearful for their livelihood.[1] The replacement was delivered. Hattersley's prospered developing an extensive catalogue, adding new products to their range which included as tobacco machines and garden furniture. Hattersley's continued to prosper with the number of employees peaking to around 1100 just prior to the First World War. They also ventured into production and the subsidiary companies have survived where the parent did not. It closed in 1983.
Hattersley produced a huge range of types of looms over 120 years for all sectors of the market, from the narrow band looms to sheeting looms, have about 26 basic models in their catalogue at one time.
Hattersley Dobby Loom In 1867 George Hattersley and Sons created a loom with a dobby head. A dobby a mechanical heald lifting device which allowed weaving of much more intricate patterns on any looms to which it was fitted.
Hattersley Narrow Fabric Loom In 1908 Hattersley developed the world's first smallware (or narrow fabric) loom, these were suitable for weaving wicks for oil lamps, and the webbing that is used in the automotive industry. To demonstrate this loom, the firm bought the Cabbage Mills and later the Greegate Shed in Keighley where they started production of these products. The firm survives today as Hattersley Aladdin Ltd.
Hattersley Standard Loom In 1921 the Hattersley Standard Loom, designed and built by the company, was to sell in its thousands, bringing considerable financial success to the company.After the recapitalisation boom of 1919 cotton yarn production peaked in 1926, a further investment was sparse. Rayon, artificial silk, was invented in the 1930s inSilsden nearby, and the Hattersley Silk Loom was adapted to weave this new fabric.
Hattersley Domestic Loom The Hattersley Domestic Loom was part of the Hattersley Domestic System that include other machines such as pirn winder and warping mill. It was a compact machine, combing all the know how and precision engineering of the nineteenth century with the need for a treadle operated loom. This looms has tappets to control up to 8 shafts, healds or boards; most simply have 4 shafts and a set of four 2/2 Twill tappets and four plain weave tappets. 5,6,7,and 8 pick tappets were available. In order to cope with the different gearings the tappet drive cog on the bottom drive shaft could be adjusted and there are two sizes of tapped mounting drive cogs. There was also a Dobby version.
The first thirty Hattersley's were sent to the Outer Hebrides in 1919. These were 36 inches in the reed space and single shuttle. In 1924 the first six shuttle, 40 inch reed space looms arrived in Stornoway and this type of loom was the most commonly used loom in the islands' Harris Tweed Industry.
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B.Power loom
Automatic looms or conventional automatic looms
To get high productivity and good quality of fabric, additional mechanisms are added to ordinary non-automatic power looms. These looms are becoming popular because of their advantages of versatility and relative cheapness. Examples :
1. Pirn changing automatic loom
2. shuttle changing automatic loom.
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B.Power loom
Automatic looms or conventional automatic looms
To get high productivity and good quality of fabric, additional mechanisms are added to ordinary non-automatic power looms. These looms are becoming popular because of their advantages of versatility and relative cheapness. Examples :
1. Pirn changing automatic loom
2. shuttle changing automatic loom.
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B.Power loom
Automatic looms or conventional automatic looms
To get high productivity and good quality of fabric, additional mechanisms are added to ordinary non-automatic power looms. These looms are becoming popular because of their advantages of versatility and relative cheapness. Examples :
1. Pirn changing automatic loom
2. shuttle changing automatic loom.
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Projectile Loom:
Sulzer brothers, Winterthur, Switzerland, Who are pioneer in the field of projectile method of weft insertion, have been able to convert a brilliant concept Roshman into a viable commercial weaving machine. It is introduced in the market in 1953.The main feature of this machine is weft insertion system. A bullet like shuttle 90 mm long & weighting about 40 g, technically named as gripper projectile is used here to insert the weft thread into the warp threads.
Figure: Projectile loom Conventional Loom Versus Projectile Loom:
Sulzer projectile weaving machine differs from a conventional automatic loom mainly in two respects.
1. The method of insertion of weft into the warp shed 2. The method of moving the reed and the projectile track
Main Features of Projectile Loom:
1. The picking are projectile receiving units are separated from the moving sley. The sley carries the reed & gripper guides. 2. The gripper projectile made of fine steel, 90 mm long 14mm wide and 6 mm thickness weight is 40 g. It carries the weft thread into the warp shed. 3. The weft is drawn directly from a large stationary cross wound package. There is no weft winding. 4. The gripper projectile is picked across the warp shed at a very high speed ,the picking energy being derived from the energy stored in a metal torsion bar which is twisted at predetermined amount of released to give the projectile a high rate of acceleration .
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5. Picking always takes place from one side, but several projectiles are employed and all of them return to the picking side by a conveyor chain located underneath the warp shed. 6. During its flight through the shed the projectile runs in a rake likes steel guides, so that the warp threads are touched neither by the projectile nor weft thread. 7. Every pick is cut off at the picking side near the selvedge after weft insertion, leaving a length about 15 mm from the edge. Similar length of weft also projects from the selvedge on the receiving side. 8. The ends of weft thread projecting on both sides of the cloth are tucked into the next shed by means of special tucking device and woven in with next pick, thus providing firm selvedges. 9. The reed is not reciprocated as in a shuttle loom, but rocked about its axis by a pair of cams. 10. The reed & projectile guides are stationary during pick insertion. 11. The sley which carries the reed & projectile guides is moved forward & backward through a saddle carrying two follower bowls, which bear against the surface of two matched cams. 12. A sley dwell of 25 degree at back center enables the projectile to travel through the warp shed without being unnecessary reciprocated by the sley. 13. Whenever the reed width is reduced for weaving a small width cloth from the standard reed width, the projectile receiving unit is moved inward on the telescope shaft, to the new selvedge position, and so the projectile travel distance is reduced. 14. Smaller shed opening because of the smaller size projectile. This might result in lower warp breakage rate. 15. Weft insertion rate up to 900-1500 m/min is possible depending up to the width of the weaving machine. 16. The color changing mechanism is less complicated. 17. In case of weft breakage the take up beam & heald frames can de driven in reverse by a pick finding mechanism.
Advantages of Projectile Loom as a Modern Loom:
1. Two or three cloths can be woven simultaneously.
2. It is possible to achieve weaving performances with breakage rate per square meter of cloth. 50% of the number of breaks that would occur on a conventional loom.
3. The lower warp breakage rate in a projectile weaving machine may be due to:
Smaller warp shed Reed with higher ratio of air to wire (70:30) Beat up line being nearer to the centre of the reed between the two baulks.
Smaller warp shed will reduce the warp threads tension to some extent. However care should be taken to maintain uniform tension to ensure that the warp shed is of same depth from one end to another. Otherwise a few slack warp threads at the top shed will result in stitching and end cut of the projectile.
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4. Since the projectile is passing through guides there is no reed to projectile or projectile to yarn contact.
5. With the introduction of four/six colors weaving machine all the mechanical problems of the conventional pick & pick multicolored loom are eliminated.
Rapier Loom:
Insertion of weft by rapier is a mechanically modern & refined version of the primitive method of fabric production in which the weft was secured in a slot of a stick. At present version of the gripper head which are attached to rapiers which are flexible tapes or rigid rods. Mr. John Gabler can be regarded as the father of modern rapier technology he has built a rapier device on a cotton weaving machine in 1922.
Scope of Rapier:.
Single rapier loom can insert weft only on alternate rapier traverse. In many cases this is modified to achieve a higher rapier velocity in the early and late parts of the movement and thus a over maximum velocity halfway through the movement. Due to high rate of insertion the possibility of yarn breakages rate may increase. Additionally, it is necessary to control the weft by passing it trough an effective tension arrangement so that the weaving tension will be more uniform, this can also occurred weft break.
Features of Rapier Loom:
1. An useful feature of rigid rapiers is that they can be simultaneously inserted in two sheds one above the other, for producing double plush and certain carpets. 2. Rapier loom may have various types according to the weft insertion mechanism & number of pick such as insertion of double pick, insertion of single pick, two phase rapier etc. 3. In all rapier looms to-and-fro-movement of the rapiers is derived initially either from a linkage mechanism or from a cam. The use of linkage mechanism has the advantages of simplicity reliability & is cheap, quite and consumers less energy than a cam mechanism but it does not provide any dwell to the rapiers. 4. The only two phase rapier in commercial operation is the saurer of width 2 x 185 cm or 2 x 220 cm having weft insertion rate is about 1200 mpm. 5. The rigid rapier is driven from the centre and has a rapier head at each end.In one cycle of 360 degree the rapier inserts one pick alternately in the right hand and the left hand fabrics, the picks being inserted and beaten up in opposite phase . 6. In gabler system of weft insertion the rapier system is combined with air jet picking system.
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7. Gabler system rapier may be single sided or double sided. The machine include on gabler system Draper DSL,Gusken etc.Those operating on dewas system include dornier, picanol, Novo pignon SACM, Gunne, Smit, Sommet, Sulzer-Ruti etc.
Rapier Loom Integrating the features of rapier looms of Model SJ758 and other imported and domestic rapier looms, Model SJ736-III rapier loom is specially designed for weaving of light, medium and heavy fabrics and check designs, it adopts automatic pick finder and electronic color selector.
Control panel:
The loom is controlled by the control panel with a micro-computer, the lcd display provides a very user-friendly human-machine interface, which shows the production statistic data of each shift and provides the weft color programming function.
Weft color selection:
The machine adopts electronic color selector up to 8 colors, and the color selection pattern is programmed directly on the machine control panel
Wefting: Wefting mechanism adopts 6-lever wefting structure and can ensure the adjustment of the rapier entry and exit time and ensure stable wefting and insertion motion. This machine adopts 4 levers, short connectors and short sley to complete the beating motion, the rock shaft adopts 110mm(diameter) seamless tube to ensure the beating strength and can be suitable for high-speed motion and weaving of heavy and high density fabrics. The rapier transmission box adopts the advanced helix umbrella gears to ensure stable transmission. The tension device adopts 3-rear- beam tension structure, which is specially designed for balancing the warp tension of high- density weaving and can improve the quality of the weaving fabrics.
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Pick finding mechanism:
The machine adopts electronic let-off mechanism with a high-accuracy step motor and the optimized mechanical take-up system for stable and accurate pick finding motion. The pick finding motion is very stable and proved to be very successful and reliable.
The adoption of two pressing rollers on the fabric winding roller enables the worker to unload the fabric from the fabric roller without stop. The frequent adoption of bearings for the major moving parts provides better performance and easier maintenance.
Advantages of Rapier Loom: Over Conventional Loom:
1. The rapier loom doesn’t require dynamic forces or anything like the magnitude as those involved in the conventional loom. 2. The weft insertion rate in a rapier loom is very much influenced by the method of weft control. 3. Weft insertion rate is very high rather than any conventional loom 4. It can occur double pick at a time by double picking insertion system. Here is no need to cut the weft selvedges and no weft wastage. 5. Weft insertion rate is very high rather than any conventional loom Rigid rapiers has a useful features that they can be simultaneously inserted in two sheds one above the other ,for producing double plush and certain carpets. 6. Looms that use rigid rapiers eliminate entirely the need to assist the rapier head through the warp shed, this is a un doubted advantages.
Air Jet Loom:
Weft insertion by means of air jet has made a major breakthrough in the early 70s and its importance is increasing further because of its ability to weave a wide range of fabrics at a very high speed weft insertion rate of about 2000 mpm. The first attempt to use a compressed air steam instead of shuttle is made by Brooks in 1914.
Scope of Air Jet Loom:
To insert the weft threads here used compressed air. Not suitable for the coarser count or heavier fabric. The timing of jet activity should be controlled in such a way that the main nozzle is supplied with compressed air from the beginning of the weft insertion phase and the relay nozzles also receive compressed air. High maintenances is needed.
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Features of Air Jet Loom:
1. Air jet weaving machine is high speed machine having good quality 2. For instance on a weaving machine having a speed of 600 rpm the weaving cycle is 100m/s. 3. Cam control valves have the advantages of high speed precision of action whilst the electrically controlled solenoid valves permit easy setting. 4. Finer count of yarn is used as the weft thread to produce fency type of fabric.
Figure: Air jet loom Advantages of Air Jet Loom Over Conventional Loom:
The conventional loom requires shuttle or shuttle like substance to insert the weft yarn, comparatively in air jet loom there is no need to any kind of shuttle instead of shuttle here the compressed air force is used. In the conventional loom the pick insertion rate is very low compare to the air jet loom. The weft stop motion is machine controlled over the differ from conventional loom In conventional loom the mechanical or hand shuttle reach the weft thread to the fell of the cloth, but in air jet through air force this is done, here uniform let up, take up, uniform picking, uniform bet up is possible. It has the automatic weft repair device.
Disadvantages:
Short or buckle pick Loose pick Snarling Excess dynamic pressure Weft stop problem Tip problem
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Timing of shed may not be proper Too high or too low main nozzle pressure Left side warp yarn is loose.
Water Jet Loom:
The first loom to make use of a water jet for insertion of weft was developed by Satyr.The loom was first shown at the Brussels textile Machinery Exhibition in 1995.
Scope of Water Jet Loom:
Weft and warp yarn must be insensitive .i.e hydrophobic in nature. Weaving of the water attractive fabric is not possible by the water jet loom, Thermoplastic yarns offer the advantages of severance of weft by a heated blade and the provision of a heat selvedge by fusing. It has required miniature pump to feed water under pressure to the nozzle.
Figure: Water Jet loom.
Features of Water Jet:
The water jet loom demonstrated at ITMA ASIA 2005 as a concept model now has debuted as the “ZW8100.” The new model “ZW8100” inherited the basic abilities of the “ZW series” that has enjoyed an excellent reputation as the global standard water jet loom and has enhanced stability at high speed. The ZW8100 intends to succeed and advance the long-cultivated basic abilities of water jet looms – weaving technology, high- speed ability, quality, and energy-saving – for the next hundred years.
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Tsudakoma consistently emphasises the basic abilities: high speed, quality, versatility, eco- friendliness. Tsudakoma particularly focuses on ultra high speed ability - the mission of all jet looms. Because it considers ultra high speed as the base, Tsudakoma has optimised the frame structure, the beating system and the shedding system, and employs a newly-developed nozzle. A navigation system that enjoys a good reputation for air jet looms is also employed while taking careful note on higher versatility and better operability. To give the best answer to reply to market demands, fulfilling basic abilities is indispensable. Flexibility to woven material is also increased. True user-friendliness is attained.
The ZAX9100 is well-established for its ultra-high speed ability. The “ZAX9100HD” is a package model that can weave heavy fabrics at high speed while keeping quality high with enhanced basic abilities and new technology. Tsudakoma’s unique heavy-duty structure responds to user’s strict quality demands. The exhibit demonstrated weaving quality yarn-dyed shirting at high speed.
The ZAX9100 is ranked as a premium air jet loom provided with the “Weave Navigation System.” It handles diverse responsibilities, such as being cost-competitive, quick style change, value-added fabrics, and developing new fabrics that will be required more than ever. The ESS Electronic Shedding System, 6-colour weft selection, and the PSC support weaving value-added fabrics of various kinds and thickness wefts. The PSC Programmable Speed Control controls the rpm per one pick according to weft kinds and fabric weaves in order to attain stable weaving, thus the operation efficiency is considerably increased. Fabrics formerly limited to rapier looms are woven easily keeping quality.
Tsudakoma has the largest air jet terry weaving experience in the world. Many terry weavers consider Tsudakoma’s air jet looms the standard. While fusing the ultra-high speed ability of the ZAX9100 with its abundant terry weaving know-how, various elaborately designed towels such as pileheight changes and pile-cycle switching between 3 to 7-picks can be woven with a pleasant texture. In combination with the electronic Jacquard motion higher value-added terry cloth can be woven.
The “Versa-Terry System” is the integration of Tsudakoma’s terry weaving technology. Various systems that Tsudakoma developed especially for terry are enhanced and new technology for weaving diversified terry cloth designs is employed. The “Versa-Terry System” inherits and advances the thorough experience of the world’s largest record of air-jet terry weaving machines. Improving all of its basic abilities: speed, versatility, quality, energy saving, operability, the ZAX9100-Terry realizes true user-friendliness.
Water Jet Loom Advantages:
Water jet propulsion has many advantages over other forms of marine propulsion, such as stern drives, outboard motors, shafted propellers and surface drives. These advantages include...
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Excellent Maneuverability
Precise steering control at all boat speeds "Zero Speed" steering effect provides 360° thrusting ability for docking and holding stationary. Sideways movement possible with multiple jet installations. High efficiency astern thrust with "power-braking" ability at speed
High Efficiency
Propulsive coefficients as good or higher than the best propeller systems achievable at medium to high planning speeds Flexibility when using multiple water jets may allow operators to continue to operate efficiently on fewer drives
Low Drag and Shallow Draught
Absence of underwater appendages reduces hull resistance Shallow draught - the water jet intake is flush with hull bottom to allow access to shallow water areas and beach landings with no risk of damage to the drive
Low Maintenance
No protruding propulsion gear eliminates impact damage or snags Minimum downtime and simple maintenance routines
Smooth and Quiet
No hull vibration, no torque effect and no high speed cavitations gives maximum comfort levels on board Low underwater acoustic signature
Total Safety
No exposed propeller for complete safety around people in the water and marine life
Maximum Engine Life
Jet unit impeller is finely matched to engine power Power absorption is the same regardless of boat speed No possibility of engine overload under any conditions
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Simplicity
Single packaged module No heavy and expensive gearbox required for many installations. Simple driveline from engine to jet coupling
Easy installation
Complete factory tested package, ready to bolt in No difficult engine alignment problems.
Multiphase Loom:
The phase number of a loom is defined as the average number of shuttles or weft carriers inserting weft simultaneously. It is shown that existing multi-phase looms must have high phase numbers to compensate for their low shuttle velocity. The analysis suggests that looms with high-velocity flying shuttles would achieve equally high weft-insertion rates with moderate increases in the phase number. Such moderate increases in the phase number can be obtained by dividing the shedding and beat-up motions into a comparatively small number of sections. The suggested alternative would avoid many of the textile and engineering problems arising in existing multi-phase looms.
Figure: Multiphase loom
Features of Multiphase Loom:
1. A multi-phase loom with magnetic shuttle features that the spiral reed blade with shuttle path is used for beating-up. 2. The linear motor is used for wefting, the heald wheel or electromagnetically excited heald needle is used for opening, and the weft opening with off-line multi-path asynchronous weft replenishing is used. 3. Its advantages include high efficiency, high speed and low weaving cost.
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4. The multiphase loom can form many different sheds at different places, thereby enabling insertion of number of filling yarns, one behind the other.
Advantages of Multiphase Loom Over Conventional Loom:
1. An analysis of the factors determining the weft-insertion rate of weaving machines shows that these factors are essentially the same on all looms in which shuttles or weft carriers are used, such as conventional shuttle looms, gripper- shuttle looms, and multi-phase looms. 2. Its advantages include high efficiency, high speed and low weaving cost. 3. The multiphase loom can form many different sheds at different places, thereby enabling insertion of number of filling yarns, one behind the other.
সোমবার, ১১ নভেম্বর, ২০১৩
The Planetary Society
The Mars Orbiter Mission completed its first, second, and third of six planned maneuvers in Earth orbit successfully last week. However, the fourth maneuver, conducted on Sunday at 12:36 PST / 20:36 UTC / Monday 02:06 IST, failed to lift the apogee of the orbit as high as planned.
Messerschmitt Me 262 - জার্মানির তৈরী পৃথিবীর প্রথম জেট পাওয়ারড ফাইটার প্লেন
Messerschmitt Me 262 - জার্মানির তৈরী পৃথিবীর প্রথম জেট পাওয়ারড ফাইটার প্লেন।
এটির যাত্রা শুরু হয় ১৯৪১ সালের ১৮ এপ্রিল। অবশ্য জন্মলগ্নে ফাইটারটি ছিল পিস্টন ইঞ্জিনের। পরের বছর, ১৯৪২ এর ১৮ জুলাইএ এটিতে জেট ইঞ্জিন সংযুক্ত করা হয়।
এ পর্যন্ত প্রায় ১৫০০ এর মত Me 262 তৈরী করা হয়।
1951 সালে Me 262 কে ওড়াউড়ি ... গোলাগুলি থেকে অবসর দেয়া হয়।
এটির যাত্রা শুরু হয় ১৯৪১ সালের ১৮ এপ্রিল। অবশ্য জন্মলগ্নে ফাইটারটি ছিল পিস্টন ইঞ্জিনের। পরের বছর, ১৯৪২ এর ১৮ জুলাইএ এটিতে জেট ইঞ্জিন সংযুক্ত করা হয়।
এ পর্যন্ত প্রায় ১৫০০ এর মত Me 262 তৈরী করা হয়।
1951 সালে Me 262 কে ওড়াউড়ি ... গোলাগুলি থেকে অবসর দেয়া হয়।
মিসাইলজ অভ ফাইটার
আধুনিক যুগের ফাইটার জেটে এয়ার কমব্যাট
ম্যানুভারিং এর জন্য মূলত ২ ধরনের মিসাইল
ব্যবহার করা হয়-
হিট সিকিং আর ইলেক্ট্রো অপটিক্যাল মিসাইল.........। শেষের
টা অবশ্য ইসরাইলের নতুন আবিষ্কার।
এখন
ফাইটার জেটে ব্যবহার করার মতো মিসাইল
আছে হাজার রকমের। কোনটা কিরকম,
ভালো না খারাপ তা নিয়ে উপন্যাস
লেখার ইছা আমার নাই। আমি আজকে মিসাইল
ব্যাপারটার কাজের ধারা নিয়ে চিৎকার
করবো......
এয়ার টু এয়ার মিসাইলের ধারনাটা আসে ১ম
বিশ্বযুদ্ধে ব্যবহার করা এয়ার টু এয়ার রকেট
থেকে। তখন প্লেন গুলাতে এই টাইপের রকেট
থাকতো এবং যুদ্ধের আকাশে যখন
সামনে সমান্তরাল লাইনে কোন শত্রু বিমান
থাকতো তখন এই রকেট ছোঁড়া হতো।
এইটার কোন গাইডেন্স সিস্টেম ছিলোনা তাই
লক্ষ্যভেদের সম্ভাবনা শুধু পাইলটের
হাতে ছিল।
বিশ্বযুদ্ধের পর প্রথম এয়ার টু এয়ার
মিসাইল বানানোর চিন্তা করা হয় যা শত্রু
বিমানকে ধাওয়া করে আঘাত করবে। তখনই প্রথম
গাইডেড মিসাইল বানানোর চেষ্টা করা হয়,
যা আজ পর্যন্ত শুধু নতুন নতুন আপডেট
আকারে আসছে।
গাইডেড মিসাইলের বেসিক মূলত ইন্টারনাল
রাডার অথবা হিট সিকিং ডিভাইস এর উপর
ভিত্তি করে বানানো.........। এইটা ৫
টা জেনারেশনে বিভক্ত।
এখন, মিসাইলের গাইডেন্স যেইরকমই হোক না কেন ডগফাইটার
জেটে ব্যবহার করা মিসাইল মূলত ২
ভাগে বিভক্ত, যেমন- শর্ট রেঞ্জ আর
লং রেঞ্জ।
শর্ট রেঞ্জ মিসাইল গুলা ২০-২৭
কিলমিটার পর্যন্ত মারাত্মক কাজের। কারন
আকাশে পাইলটের চোখে এই রেঞ্জেই
সাফল্লের হার বেশি।
কিন্তু শত্রু যখন পাইলটের
দৃষ্টিসীমার বাইরে চলে যায়, তখন পাইলট
কি করবে?
ঠিক এই জন্যই আবিষ্কার করা হয়েছে.........
Beyond-visual-range missile।
এর আবিষ্কার হয়
এমন সময়ে, তখন এর কাজ করার ধরন
নিয়ে ইন্টারনেটে কিছু আসেনাই।
আমরা জানি যে শর্ট রেঞ্জ মিসাইল
গুলা রাডার দিয়ে বা ইনফ্রারেড বিম লক
করে শত্রু জেটের দিকে ছুটে যায়। কিন্তু শত্রু
দৃষ্টিসীমার বাইরে গেলে পাইলট প্লেনের
নিজস্ব
রাডারে যদি প্লেনটাকে দেখতে পারে তাহলে Beyond-
visual-range missile সেই প্লেনের দিকে লক
করতে পারে।
এই মিসাইল গুলতে রেমজেট
রকেট ইঞ্জিন সংযোগ করারা কারনে এদের
গতি অসাধারন!!!
মিসাইল লঞ্চ করার পর
মিসাইল প্রথমে ছুটে যায় লাস্ট
যেইদিকে শত্রু বিমান দেখা গিয়েছিলো।
এই মিসাইলের ভিতরে ইনপুট করা রাডার
বা হিট সিকার ১০০ নটিকাল মাইল পর্যন্ত কাজ
করে। তাই একবার মিসাইলের রেঞ্জের
মাঝে ওই শত্রু বিমান
আসলে.............. বাকিটা আপনারা বুঝেন নিন।
তবে Beyond-visual-range missile কিভাবে লক্ষ্য
খুজে এইটা কিন্তু কোথাও ঠিক
করে লেখে নাই আজ পর্যন্ত......... আমার যতটুকু
অভিজ্ঞতা তা দিয়েই আমি এইটা বের
করলাম।
ম্যানুভারিং এর জন্য মূলত ২ ধরনের মিসাইল
ব্যবহার করা হয়-
হিট সিকিং আর ইলেক্ট্রো অপটিক্যাল মিসাইল.........। শেষের
টা অবশ্য ইসরাইলের নতুন আবিষ্কার।
এখন
ফাইটার জেটে ব্যবহার করার মতো মিসাইল
আছে হাজার রকমের। কোনটা কিরকম,
ভালো না খারাপ তা নিয়ে উপন্যাস
লেখার ইছা আমার নাই। আমি আজকে মিসাইল
ব্যাপারটার কাজের ধারা নিয়ে চিৎকার
করবো......
এয়ার টু এয়ার মিসাইলের ধারনাটা আসে ১ম
বিশ্বযুদ্ধে ব্যবহার করা এয়ার টু এয়ার রকেট
থেকে। তখন প্লেন গুলাতে এই টাইপের রকেট
থাকতো এবং যুদ্ধের আকাশে যখন
সামনে সমান্তরাল লাইনে কোন শত্রু বিমান
থাকতো তখন এই রকেট ছোঁড়া হতো।
এইটার কোন গাইডেন্স সিস্টেম ছিলোনা তাই
লক্ষ্যভেদের সম্ভাবনা শুধু পাইলটের
হাতে ছিল।
বিশ্বযুদ্ধের পর প্রথম এয়ার টু এয়ার
মিসাইল বানানোর চিন্তা করা হয় যা শত্রু
বিমানকে ধাওয়া করে আঘাত করবে। তখনই প্রথম
গাইডেড মিসাইল বানানোর চেষ্টা করা হয়,
যা আজ পর্যন্ত শুধু নতুন নতুন আপডেট
আকারে আসছে।
গাইডেড মিসাইলের বেসিক মূলত ইন্টারনাল
রাডার অথবা হিট সিকিং ডিভাইস এর উপর
ভিত্তি করে বানানো.........। এইটা ৫
টা জেনারেশনে বিভক্ত।
এখন, মিসাইলের গাইডেন্স যেইরকমই হোক না কেন ডগফাইটার
জেটে ব্যবহার করা মিসাইল মূলত ২
ভাগে বিভক্ত, যেমন- শর্ট রেঞ্জ আর
লং রেঞ্জ।
শর্ট রেঞ্জ মিসাইল গুলা ২০-২৭
কিলমিটার পর্যন্ত মারাত্মক কাজের। কারন
আকাশে পাইলটের চোখে এই রেঞ্জেই
সাফল্লের হার বেশি।
কিন্তু শত্রু যখন পাইলটের
দৃষ্টিসীমার বাইরে চলে যায়, তখন পাইলট
কি করবে?
ঠিক এই জন্যই আবিষ্কার করা হয়েছে.........
Beyond-visual-range missile।
এর আবিষ্কার হয়
এমন সময়ে, তখন এর কাজ করার ধরন
নিয়ে ইন্টারনেটে কিছু আসেনাই।
আমরা জানি যে শর্ট রেঞ্জ মিসাইল
গুলা রাডার দিয়ে বা ইনফ্রারেড বিম লক
করে শত্রু জেটের দিকে ছুটে যায়। কিন্তু শত্রু
দৃষ্টিসীমার বাইরে গেলে পাইলট প্লেনের
নিজস্ব
রাডারে যদি প্লেনটাকে দেখতে পারে তাহলে Beyond-
visual-range missile সেই প্লেনের দিকে লক
করতে পারে।
এই মিসাইল গুলতে রেমজেট
রকেট ইঞ্জিন সংযোগ করারা কারনে এদের
গতি অসাধারন!!!
মিসাইল লঞ্চ করার পর
মিসাইল প্রথমে ছুটে যায় লাস্ট
যেইদিকে শত্রু বিমান দেখা গিয়েছিলো।
এই মিসাইলের ভিতরে ইনপুট করা রাডার
বা হিট সিকার ১০০ নটিকাল মাইল পর্যন্ত কাজ
করে। তাই একবার মিসাইলের রেঞ্জের
মাঝে ওই শত্রু বিমান
আসলে.............. বাকিটা আপনারা বুঝেন নিন।
তবে Beyond-visual-range missile কিভাবে লক্ষ্য
খুজে এইটা কিন্তু কোথাও ঠিক
করে লেখে নাই আজ পর্যন্ত......... আমার যতটুকু
অভিজ্ঞতা তা দিয়েই আমি এইটা বের
করলাম।
শনিবার, ৯ নভেম্বর, ২০১৩
Sikorsky CH53E Super-Stallion
Sikorsky CH53E Super-Stallion
আম্রিকার সবচেয়ে হেভি-লিফট হেলিকপ্টার, দুনিয়ার দ্বিতীয় বৃহত্তম।
*ভূমিকা: হেভি-লিফট কার্গো হেলিকপ্টার
*ম্যানুফ্যাকচারার: Sikorsky Aircraft
*প্রথম উড্ডয়ন: 1 March 1974
*প্রথম পরিচিতি: 1981
*বর্তমান অবস্থাঃ In service
*প্রাইমারী ইউজার: United States Marine Corps,
United States Navy,
Japan Maritime Self-Defense Force
*যতগুলো তৈরি হয়েছে: 234
প্রতিটির মূল্য: US $24.36 million (1992, avg. cost)
আম্রিকার সবচেয়ে হেভি-লিফট হেলিকপ্টার, দুনিয়ার দ্বিতীয় বৃহত্তম।
*ভূমিকা: হেভি-লিফট কার্গো হেলিকপ্টার
*ম্যানুফ্যাকচারার: Sikorsky Aircraft
*প্রথম উড্ডয়ন: 1 March 1974
*প্রথম পরিচিতি: 1981
*বর্তমান অবস্থাঃ In service
*প্রাইমারী ইউজার: United States Marine Corps,
United States Navy,
Japan Maritime Self-Defense Force
*যতগুলো তৈরি হয়েছে: 234
প্রতিটির মূল্য: US $24.36 million (1992, avg. cost)
:::: ডিনামাইট সম্পর্কে কিছু তথ্য :::::
ডিনামাইট প্রধানত নাইট্রো গ্লিসারিন ও টি.এন.টি(TNT) দিয়ে তৈরি একটি উচ্চ ক্ষমতা সম্পন্ন রাসায়নিক বিস্ফোরক। একটি ডিনামাইটের ক্ষমতা প্রায় দুই মিলিয়ন জুলের উপরে। ডিনামাইট আবিষ্কার করেন সুইডেনের বিজ্ঞানী আলফ্রেড নোবেল।
ডিনামাইটকে সাধারনত তার দিয়ে দূর থেকে বৈদ্যুতিক সিগন্যালের সাহায্যে বিস্ফোরণ করানো হয়। যেমন কোন পাহাড় পর্বতের বিরাট আকারের পাথরকে ভাঙ্গার জন্য প্রথমে পাথরটিতে ড্রিল মেশিন দিয়ে সারিবদ্ধভাবে ছোট ছোট ছিদ্রের সৃষ্টি করবে। প্রতিটি ছিদ্রে একেকটি ডিনামাইট প্রবেশ করিয়ে সবগুলো ডিনামাইটকে তার সংযুক্ত করে বা রিমোট কন্ট্রোলের মাধ্যমে একই সময়ে বিস্ফোরণ ঘটানো হয়। এসময় ডিনামাইট থেকে উচ্চ তাপমাত্রার বিরাট আকারের গ্যাস দ্রুতগতিতে এক মুহুর্তে বের হয়ে আসে। এ প্রক্রিয়ায় যে পার্শ্বচাপের সৃষ্টি হয় তাতেই বিরাট আকারের পাথরটি ভেঙ্গে যায়। গঠনে কিছুটা পরিবর্তন এনে ডিনামাইট যুদ্ধে ল্যান্ড মাইন হিসেবেও ব্যবহার হয়।
ডিনামাইট সবচেয়ে বেশি ব্যবহৃত হয় পাহাড় ভাঙ্গা, টানেল তৈরি ও খনিতে। কারণ খুব সহজে ও কম খরচে ডিনামাইট দিয়ে এসব কাজ করা যায়। এছাড়া যুদ্ধের কাজে শত্রুপক্ষের ভবন, সেতু, রেললাইন উড়িয়ে দিতে ডিনামাইট ব্যবহার হয়।
ডিনামাইটকে সাধারনত তার দিয়ে দূর থেকে বৈদ্যুতিক সিগন্যালের সাহায্যে বিস্ফোরণ করানো হয়। যেমন কোন পাহাড় পর্বতের বিরাট আকারের পাথরকে ভাঙ্গার জন্য প্রথমে পাথরটিতে ড্রিল মেশিন দিয়ে সারিবদ্ধভাবে ছোট ছোট ছিদ্রের সৃষ্টি করবে। প্রতিটি ছিদ্রে একেকটি ডিনামাইট প্রবেশ করিয়ে সবগুলো ডিনামাইটকে তার সংযুক্ত করে বা রিমোট কন্ট্রোলের মাধ্যমে একই সময়ে বিস্ফোরণ ঘটানো হয়। এসময় ডিনামাইট থেকে উচ্চ তাপমাত্রার বিরাট আকারের গ্যাস দ্রুতগতিতে এক মুহুর্তে বের হয়ে আসে। এ প্রক্রিয়ায় যে পার্শ্বচাপের সৃষ্টি হয় তাতেই বিরাট আকারের পাথরটি ভেঙ্গে যায়। গঠনে কিছুটা পরিবর্তন এনে ডিনামাইট যুদ্ধে ল্যান্ড মাইন হিসেবেও ব্যবহার হয়।
ডিনামাইট সবচেয়ে বেশি ব্যবহৃত হয় পাহাড় ভাঙ্গা, টানেল তৈরি ও খনিতে। কারণ খুব সহজে ও কম খরচে ডিনামাইট দিয়ে এসব কাজ করা যায়। এছাড়া যুদ্ধের কাজে শত্রুপক্ষের ভবন, সেতু, রেললাইন উড়িয়ে দিতে ডিনামাইট ব্যবহার হয়।
এতে সদস্যতা:
পোস্টগুলি (Atom)