Hydrauli Sheet Bending - Copy.docx

Hydraulic Sheet Bending 2018

FTC COER Poly (Shift), Sangola Department Of Mechanical Engineering Academic year (2017-18)

Mini Project /Project Synopsis Date:14/08/2017 Name of students (Project group) . Name of guide: Title of project: Pneumatic sheet bending. Abstract: Here, working model shows the movement & working of Pneumatic sheet bending,Which is made from hydraulic jack & angle 90^0 bending.

Project Guide F T C Sangola

Project Coordinator Page 1

Hydraulic Sheet Bending 2018

ABSTRACT

Now a day, infrastructure development is very fast growing, for that the use of R.C.C construction machinery is very widely used, but in any R.C.C construction machinery proper Mixing of raw material for Concrete is major problem. Proper mixing of raw material is important task in any construction, for that we are use latest equipments which are mechanically and hydraulically combined operated mostly. HYDRAULIC SHEET BENDING is one of them which are operated by two prime movers one prime mover is use for hydraulic system operation for operating the hoper and other for operating drum for proper mixing of concret.The work presented herein is mainly divided into the three chapters. The first chapter introduces the benching mixing machine with problem formulation and provides motivation for the project. The second chapter presents the current state of mixing machine research as presented in the form of scientific literature review.

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Hydraulic Sheet Bending 2018

INDEX

Sr. No. 1

Containt Introduction

2

Types of bending

3

Types of jack

4

Literature review

5

Working of hydraulic jack

6

Parts of jack

7

Conclusion

8

Application,Adv/Dis-adv

9

Referances

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Hydraulic Sheet Bending 2018 Chapter-1 Introduction Sheet bending is a metal forming process by which metals can be deformed or bent to the desired shapes. In sheet metal bending process force is applied on a metal part causing it to deform in a particular direction. Here the surface area of the metal part does not change but the inside part shrinks and compresses while the outside part stretches and becomes more tense. This happens because the yield and tensile strengths of the metal get disturbed when the force is applied to it. In metal bending operation metal gets deformed only along one axis but when combined with sequence of different operations, it is possible to cast even the complex shapes with sheet metal bending process. Metals are really hard and bending them is not so easy. To bend metals it is required that they are stressed beyond their yield strength and below their ultimate tensile strength and for this machines are required, the sheet metal bending machines. With sheet metal bending machines it is possible to shear and bend different kinds of sheet metals like aluminum, brass, copper, steel, tin, nickel and titanium. The sheet bending machines of the modern day are highly sophisticated models of sheet metal bending machine with which metals can be bent or straightened easily and quickly to give a desired shape with the use of bending beam or die sets available in them. Different kinds of sheet bending machines are used to perform various metal shaping and bending applications in industries. Universal Bending Machines consists of a basic machine that can be adjusted with little effort and used for a variety of bends. A simple plug-in system supports quick and easy exchange of tools. The basic machine consists of a CNC-operated side stop, a work bench, and software for programming and operating. Its modular construction offers an affordable entry into the bending technology, because after an initial investion the machine can be customized and extended later on without any conversion. That mean the basic machine delivers a bending stroke, the tool determines the kind of bending A hydraulic jack is a jack that uses a liquid to push against a piston. This is based on Pascal’s Principle. The principle states that pressure in a closed container is the same at all points. If there are two cylinders connected, applying force to the smaller cylinder will result in the same amount of pressure in the larger cylinder. However, since the larger cylinder has more area, the resulting force will be greater. In other words, an increase in area leads to an increase in force. The greater the difference in size between the two cylinders, the greater the increase in the force will be. A hydraulic jack operates based on this two cylinder system.

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Hydraulic Sheet Bending 2018 The Origin Of Hydraulic Jacks Can Be Dated Several Years Ago When Richard Dudgeon, The Owner And Inventor Of Hydraulic Jacks, Started A Machine Shop. In The Year 1851, He Was Granted A Patent For His Hydraulic Jack. In The Year 1855, He Literally Amazed Onlookers In New York When He Drove From His Abode To His Place Of Work In A Steam Carriage. It Produced A Very Weird Noise That Disturbed The Horses And So Its Usage Was Limited To A Single Street. Richard Made A Claim That His Invention Had The Power To Carry Near About 10 People On A Single Barrel Of Anthracite Coal At A Speed Of 14 M.P.H. Dudgeon Deserves A Special Credit For His Innumerable Inventions Including The Roller Boiler Tube Expanders, Filter Press Jacks, Pulling Jacks, Heavy Plate Hydraulic Hole Punches And Various Kinds Of Lifting Jacks.

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Hydraulic Sheet Bending 2018 Chapter-2

Types of bending

 U-Bending For U-bends where tight and narrow bends are necessary, the bending former is replaced by a bending mandrel. A bending mandrel has a narrow geometry.

 Offset Bending Offset bending tools are used to assemble two bends with a small distance between in one step.

 Edgewise Bending Edge bending tools are used, if the bending axis is placed parallel to the tight side of the work piece. Tools for bending on edge may include electronic angular measurement allowing a high bending accuracy.

 Torsion Bending Torsion tools are able to rotate the workpiece on the longitudinal axis. Alternatives are complex assembly groups with standard bends

 Angular Measurement and Spring Back Compensation For producing single pieces as well as small batches with the same precision and efficiency as series-produced parts, a spring back compensation is helpful. A bending accuracy of +/- 0.2° starting from the first work piece is achieved due to calculated spring back compensation and the use of electronic tools.

 Operating Mode Angular Measurement Bending prisms with electronic angular measurement technology are equipped with two flattened bending bolds. That bold rotate while bending giving a signal to the angle measurement. The measuring accuracy is about 0.1º. The computer then calculates the required final stroke and spring back of every bend is compensated regardless of material type. F T C Sangola

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Hydraulic Sheet Bending 2018 A high angle accuracy of +/- 0.2º is achieved instantly with the first workpiece without adjustments. Compared to adjustment by reference, material waste amounts are decreased, because even inconsistencies within a single piece of material are automatically adjusted .

 Operating Mode Stroke Measurement Wherever Bending prisms with electronic angular measurement are not suitable, a small distance between the bends might be a reason, bending prisms without electronic angle measurement are applied. In that case the control unit can be switched from angular measurement to stroke measurement. This method allows the pre-selection of the stroke of the bending ram in mm and therefore the immersion depth of the punch into the prism. Setting accuracy is +/- 0.1 mm. A final stroke is usually not required. Further development of the stroke system enables the user to specify an angle from which the stroke is calculated by using stored stroke functions. Bending accuracy in that case is dependent on material properties such as thickness, hardness, etc. which may differ from one work piece to another In actuality, the first true Bernoulli equation was derived by Euler, an outstanding mathematician, from his equations of acceleration for the conditions of steady, irrotational flow under gravitational action. Euler also deserved credit for a number of equations of hydraulics and for inventing at least on paper a workable hydraulic turbine. Worthy of mention in the same breath as Euler and the Bernoullis was Jean Lerond d'Alembert (1717-83), best known for his coeditorship of the French encyclopedia but also a mathematician in his own right. He proved in 1752 that under steady, irrotational conditions a fluid should offer no resistance to the relative motion of an immersed body: the d'Alembert paradox. D'Alembert is also known for having been one of three French scientists to have made in 1775 what were said to have been the first towing-tank tests of ship-model drag.they were, however, preceded by some nine years by those of our own Benjamin Franklin (1706 90), himself a potential hydraulician!

 Features The jack uses compressible fluid, which is forced into a cylinder by a plunger. Oil is usually used for the liquid because it is self-lubricating and has stability compared with other liquids. When the plunger comes up, it pulls the liquid through a check valve suction pump. When the plunger is lowered again, it sends liquid through another valve into a cylinder. A ball used for suction in the cylinder shuts the cylinder and pressure builds up in the cylinder. F T C Sangola

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Hydraulic Sheet Bending 2018 The suction valve present in the jack opens at each draw of the plunger. The discharge valve, which is outside the jack, opens when oil is pushed into the cylinder. The pressure of the liquid enables the device to lift heavy loads. The device pushes liquid against a piston; pressure is built in the jack's container. The jack is based on Pascal's law that the pressure of a liquid in a container is the same at all pointIn actuality, the first true Bernoulli equation was derived by Euler, an outstanding mathematician, from his equations of acceleration for the conditions of steady, irrotational flow under gravitational action. Euler also deserved credit for a number of equations of hydraulics and for inventing at least on paper a workable hydraulic turbine. Worthy of mention in the same breath as Euler and the Bernoullis was Jean Lerond d'Alembert (1717-83), best known for his coeditorship of the French encyclopedia but also a mathematician in his own right. He proved in 1752 that under steady, irrotational conditions a fluid should offer no resistance to the relative motion of an immersed body: the d'Alembert paradox. D'Alembert is also known for having been one of three French scientists to have made in 1775 what were said to have been the first towing-tank tests of ship-model drag.they were, however, preceded by some nine years by those of our own Benjamin Franklin (1706 90), himself a potential hydraulician.

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Hydraulic Sheet Bending 2018

Chapter-3

Types of jack

Hydraulic jack In 1838 William Joseph Curtis filed a British patent for a hydraulic jack In 1851, inventor Richard Dudgeon was granted a patent for a "portable hydraulic press" - the hydraulic jack, a jack which proved to be vastly superior to the screw jacks in use at the time. Hydraulic jacks are typically used for shop work, rather than as an emergency jack to be carried with the vehicle. Use of jacks not designed for a specific vehicle requires more than the usual care in selecting ground conditions, the jacking point on a vehicle, and to ensure stability when the jack is extended. Hydraulic jacks are often used to lift elevators in low and medium rise buildings. Hydraulic jacks are typically used for shop work, rather than as an emergency jack to be carried with the vehicle. Use of jacks not designed for a specific vehicle requires more than the usual care in selecting ground conditions, the jacking point on the vehicle, and to ensure stability when the jack is extended. Hydraulic jacks are often used to lift elevators in low and medium rise buildings. A hydraulic jack uses a fluid, which is incompressible, that is forced into a cylinder by a pump plunger. Oil is used since it is self lubricating and stable. When the plunger pulls back, it draws oil out of the reservoir through a suction check valve into the pump chamber. When the plunger moves forward, it pushes the oil through a discharge check valve into the cylinder. The suction valve ball is within the chamber and opens with each draw of the plunger. The discharge valve ball is outside the chamber and opens when the oil is pushed into the cylinder. At this point the suction ball within the chamber is forced shut and oil pressure builds in the cylinder. In a bottle jack the piston is vertical and directly supports a bearing pad that contacts the object being lifted. With a single action piston the lift is somewhat less than twice the collapsed height of the jack, making it suitable only for vehicles with a relatively high clearance. For lifting structures such as houses the hydraulic interconnection of multiple vertical jacks through valves enables the even distribution of forces while enabling close control of the lift. F T C Sangola

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Hydraulic Sheet Bending 2018 In a floor jack (aka 'trolley jack') a horizontal piston pushes on the short end of a bellcrank with the long arm providing the vertical motion to a lifting pad, kept horizontal with a horizontal linkage. Floor jacks usually include castors and wheels, allowing compensation for the arc taken by the lifting pad. This mechanism provide a low profile when collapsed, for easy maneuvering underneath the vehicle, while allowing considerable extension.

A hydraulic jack uses a liquid, which is incompressible, that is forced into a cylinder by a pump plunger. Oil is used since it is self lubricating and stable. When the plunger pulls back, it draws oil out of the reservoir through a suction check valve into the pump chamber. When the plunger moves forward, it pushes the oil through a discharge check valve into the cylinder. The suction valve ball is within the chamber and opens with each draw of the plunger. The discharge valve ball is outside the chamber and opens when the oil is pushed into the cylinder. At this point the suction ball within the chamber is forced shut and oil pressure builds in the cylinder. In a floor jack (aka 'trolley jack') a horizontal piston pushes on the short end of a bellcrank, with the long arm providing the vertical motion to a lifting pad, kept horizontal with a horizontal linkage. Floor jacks usually include castors and wheels, allowing compensation for the arc taken by the lifting pad. This mechanism provides a low profile when collapsed, for easy maneuvering underneath the vehicle, while allowing considerable extension.

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Hydraulic Sheet Bending 2018 Bottle jack A bottle jack or whiskey jack] is a jack which resembles a bottle in shape, having a cylindrical body and a neck. Within is a vertical lifting ram with a support pad of some kind fixed to the top. The jack may be hydraulic or work by screw action. In the hydraulic version the hydraulic ram emerges from the body vertically by hydraulic pressure provided by a pump either on the baseplate or at a remote location via a pressure hose. With a single action piston the lift range is somewhat limited, so its use for lifting vehicles is limited to those with a relatively high clearance. For lifting structures such as houses the hydraulic interconnection of multiple vertical jacks through valves enables the even distribution of forces while enabling close control of the lift. The screw version of the bottle jack works by turning a large nut running on the threaded vertical ram at the neck of the body. The nut has gear teeth and is turned by a bevel gear spigotted to the body, the bevel gear being turned manually by a jack handle fitting into a square socket. The ram may have a second screwed ram within it, which doubles the lifting range telescopically.

Bottle jacks have a capacity of up to 50 tons and may be used to lift a variety of objects. Typical uses include the repair of automobiles and house foundations. Larger, heavy-duty models may be known as a barrel jack. This type of jack is best used for short vertical lifts.Blocks may be used to repeat the operation when a greater amount of elevation is required.

Air hydraulic jack

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Hydraulic Sheet Bending 2018 An air hydraulic jack is a hydraulic jack that is actuated by compressed air - for example, air from a compressor - instead of human work. This eliminates the need for the user to actuate the hydraulic mechanism, saving effort and potentially increasing speed. Sometimes, such jacks are also able to be operated by the normal hydraulic actuation method, thereby retaining functionality, even if a source of compressed air is not available.

Inflatable jack

A demonstration of using two stacked air bags to lift the rear of the car.

An inflatable jack, lifting bag, or pneumatic lifting bag is an air bag that is inflated by compressed air (without a hydraulic component) in order to lift objects. The bag can be deflated to be reused later. The objects can be of a smaller load such as an automobile or it can be a larger object such as an airplane. Air bags are also used by rescuers to lift heavy objects up to help victims who are trapped under those objects. There are three main types of lifting bags for rescue: high pressure, medium pressure and low pressure systems. Low-pressure bags are operated at 7.25 psi for high vertical lift in a large surface area but lower lifting capacities. Medium-pressure bags are operated at 15 psi. High-pressure bags which have higher lifting capacities are operated at pressure between 90 and 145 psi. Two air bags can be stacked together to provide a higher lift. It is recommended that no more than two bags can be used in a stacked configuration, the bigger bag must be the bottom one, and no other objects are inserted between the stacked bags. Incorrect use of stacked bags may result in a bag (or other objects) shooting out to create a dangerous projectile.

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Hydraulic Sheet Bending 2018 Mechanical jack

Mechanical jack Jackscrews are integral to the Scissor Jack, one of the simplest kinds of car jacks still used. A mechanical jack is a device which lifts heavy equipment. The most common form is a car jack, floor jack or garage jack which lifts vehicles so that maintenance can be performed. Car jacks usually use Mechanical advantage to allow a human to lift a vehicle by manual force alone. More powerful jacks use hydraulic power to provide more lift over greater distances. Mechanical jacks are usually rated for a maximum lifting capacity (for example, 1.5 tons or 3 tons). The jack shown at the right is made for a modern vehicle and the notch fits into a hard point on a unibody. Earlier versions have a platform to lift on the vehicles' frame or axle.

Pneumatic jack A pneumatic jack is a hydraulic jack that is actuated by compressed air - for example, air from a compressor instead of human work. This F T C Sangola

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Hydraulic Sheet Bending 2018 eliminates the need for the user to actuate the hydraulic mechanism, saving effort and potentially increasing speed.

Sometimes, such jacks are also able to be operated by the normal hydraulic actuation method, thereby retaining functionality, even if a source of compressed air is not available. A house jack, also called a screw jack is a mechanical device primarily used to lift houses from their foundation. A series of jacks are used and then wood cribbing temporarily supports the structure. This process is repeated until the desired height is reached. The house jack can be used for jacking carrying beams that have settled or for installing new structural beams. On the top of the jack is a cast iron circular pad that the 4" × 4" post is resting on. This pad moves independently of the house jack so that it does not turn as the acmethreaded rod is turned up with a metal rod. This piece tilts very slightly but not enough to render the post dangerously out of plumb

Farm jack

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The farm jack is also known as a Hi-Lift Jack or railroad jack. The farm jack, invented in 1905, consists of a steel beam with a series of equally spaced holes along its length, and a hand operated mechanism which can be moved from one end of the beam to the other through the use of a pair of climbing pins. Typical sizes for the farm jack are 4 feet (1.2 m), 5 feet (1.5 m)and 6 feet (1.8 m) referring to the length of the beam. The jack's versatility stems from its use for such applications as lifting, winching, clamping, pulling and pushing. It is this versatility, along with the long travel it offers and its relative portability, which make the farm jack so popular with offroad drivers.

So strong an impression had Danel's collection of source material made upon me that I soon began to purchase similar works for the institute, with the collaboration of the late Frank Hanlin, bibliographer of The University of Iowa Libraries, using funds acquired through the sale of the History and other books written by the institute staff. These were placed in the University Libraries' Special Collections, and at present a catalog of the collection is being prepared for publication. Essentially all of the books cited in these pages are included therein. In fact, some 350 individual items are now at hand the finest collection that I know to exist on the history of hydraulics.

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Chapter-4 LITERATURE REVIEW

If the word hydraulics is understood to mean the use of water for the benefit of mankind, then its practice must be considered to be even older than recorded history itself. Traces of irrigation canals from prehistoric times still exist in Egypt and Mesopotamia; the Nile is known to have been dammed at Memphis some six thousand years ago to provide the necessary water supply, and the Euphrates River was diverted into the Tigris even earlier for the same purpose. Ancient wells still in existence reach to surprisingly great depths; and underground aqueducts were bored considerable distances, even through bedrock. In what is now Pakistan, houses were provided with ceramic conduits for water supply and drainage some five thousand years ago; and legend tells of vast flood-control projects in China barely a millenium later. All of this clearly demonstrates that men must have begun to deal with the flow of water countless millenia before these times. Though both the art and the science of hydraulics treat of such flows, they obviously differ significantly in time and substance. Hydraulic practice necessarily originated as an art, for the principles involved could be formulated only after long experience with science in general and water in particular. However necessary the conduct of the art thus was to the eventual development of the science, it is almost exclusively with the science of hydraulics that the present article will deal. As a matter of fact, the subiect matter of the traditional college course in hydraulics -- particularly as it was taught in the not-too-recent past -- provides a framework on which the history of the science can conveniently be based. Such a course usually began with the topic of hydrostatics -- the characteristics of liquids at rest. Instructors then proceeded to the principle of continuity (the conservation of fluid mass) and a form of the work-energy principle known as the Bernoulli theorem. In passing, note was taken of means of measuring velocity, pressure, and discharge, including the use of smallscale models to simulate flow conditions in themselves too large to test. These principles were then applied to the study of flow from orifices, over weirs, through closed and open conduits, and past immersed bodies. Simple as such matters now seem when taught, they actually took centuries to understand. Particularly noteworthy is the fact that many such principles were first clarified by men like Isaac Newton whose interests extended far beyond hydraulics itself. This scienceactually had its origins some two millenia ago in the course of Greek civilization. It must be granted, however, that Greek physics was of such a hypothetical nature that with one exception it had little positive influence in the millenia to follow. The part that concerns us here is the then-prevailing belief that the universe consists of four elements (fire, air, water, and earth), that each is displaced by the next in order of increasing weight, and that the F T C Sangola

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Hydraulic Sheet Bending 2018 space around us must be occupied by one element or another. "Nature," in other words, "abhors a vacuum." In due time the concept of a fifth element, ether, came into being, for want of something to fill outer space. To the Greeks, the abhorrence of a vacuum served to explain free flight, a body in motion presumedly being driven by the fluid closing in behind. Known as the medium theory of motion, this was one of the teachings of Aristotle (384-322 B.C.), who wrote on a wide variety of subjects ranging from physics to metaphysics. The so-called impetus theory of motion was proposed nearly a thousand years after Aristotle's time; however, because impetus could not be seen, the concept was not generally accepted, and the medium theory remained in favor for at least another millenium. The Greekwho made the most lasting contribution to hydraulics was the Sicilian mathematician Archimedes (287-212 B.C.), who reasoned that a floating or immersed body must be acted upon an upward force equal to the weight of the liquid that it displaces. This is the basis of hydrostatics and also of the apocryphal story that Archimedes made this discovery in his bath and forthwith ran un clothed through the streets crying "Eureka!" Nevertheless, even though Archimedes' writings, like those of his fellow Greeks, were faithfully transmitted to the West by Arabian scientists, further progress in hydrostatics was not to be made for another 18 centuries. In the course of the millenium following the time of Archimedes, the science of hydraulics retrogressed rather than advaneed. True, though the Romans developed extensive water-supply and drainage systems, and windmills and water wheels appeared on the scene in increasing numbers, these represented the art rather than the science. Paradoxically, although Aristotle taught that knowledge must progress, his teachings eventually came to be crystallized, so to speak, and in the time of Saint Thomas Aquinas (1225-74), they were even adopted as gospel truth by the church. In the same period, on the other hand, researchers in the early universities particularly Paris, Oxford, and Cambridge gradually began to establish simple mechanical relationships such as that between velocity and acceleration. Whereas the Greeks tended to reason without recourse to observation, it was the Italian genius Leonardo da Vinci (1452-1519) who first emphasized the direct study of nature in its many aspects. Leonardo's hydraulic observations extended to the detailed characteristics of jets, waves, aud eddies, not to mention the flight of birds and comparable facets of essentialIy every other field of knowledge. In particular, it was Leonardo who first correctly formulated the basic principle of hvdraulics known as continuity: the velocity of flow varies inversely with the cross-sectional area of a stream. Unfortunately, not only were his copious notes writteu in mirror image (probably for reasons of secrecy), but, in addition, most of them were lost for several centuries after his death. Thus his discoveries had little effect on the growth of the science. The second essential coutribution to hydrostatics was made by the Dutch hydraulic engineer Simon Stevin (1548-1620) in 1586, nearly two millenia after the time of Archimedes. Stevin showed that the force exerted by a liquid on the base of a vessel is equal to the weight of a liquid column extending from the base to the free surface. That this force does not depend on the shape of the vessel became known as the hydrostatic paradox. If Leonardo was the first scientific observer of note, it was Galileo (1564-1642) who added experimentation to observation, thereby throwing initial light on the problem of F T C Sangola

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Hydraulic Sheet Bending 2018 gravitational acceleration. In his study of the phenomenon, he noted that a body sliding freely down an inclined plane attained a certain speed after a certain vertical descent regardless of the slope; it is said that he hence advised an engineer that there was no point in eliminating river bends, as the resulting increase in slope would have no effect! Whereas Leonardo was a loner, Gallleo gathered a small school around him. One of his students, the Abbe Benedetto Castelli (c.1577-c.1644), rediscovered the principle of continuity and delved further into other aspects of the science, though not always correctly. His younger colleague Evangelista Torricelli (1608-47) applied his mentor's analysis of parabolic free-fall trajectories to the geometry of liquid jets. Torricelli also experimented with the liquid barometer, the vacuum above the liquid column being comparable to the void that Galileo found to develop in a pump whose suction pipe exceeded a certain length; in other words, nature abhorred a vacuum only up to a certain point! The French scientist Edme Mariotte (1620-84) is often called the father of French hydraulics because of the breadth of his experimentation; this included such matters as wind and water pressure and the elasticity of the air, a quality which we usually associate with the name of the Englishman Robert Boyle (1627-91) whereas the latter appears to have coined the word hydraulics, in France Boyle's law bears the name of Mariotte. Only a few years younger than Mariotte, the Italian Domenico Guglielmini (1655-1710) is similarly considered by many to have been the founder of the Italian school. But whereas Mariotte was a laboratory experimenter, Guglielmini made extensive field measurements of river flow. Interestingly enough, Guglielmini eventually became a professor of medicine! At about the same time, the short-lived French savant Blaise Pascal (1623-62) concerned himself with the same barometric problems as the equally short-lived Torricelli (not to mention Mariotte), but it was Pascal who finally completed the principles of hydrostatics. Not only did he clarify the transmissibility of pressure from point to point and its application to the hydraulic jack, but he also showed that the barometric (i.e., atmospheric) pressure must vary with elevation and hence that the barometer would have a zero reading in a vacuum.

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Chapter-5

Working of hydraulic jack

Hydraulic jacks and many other technological advancements such as automobile brakes and dental chairs work on the basis of Pascal's Principle, named for Blaise Pascal, who lived in the seventeenth century. Basically, the principle states that the pressure in a closed container is the same at all points. Pressure is described mathematically by a Force divided by Area. Therefore if you have two cylinders connected together, a small one and a large one, and apply a small Force to the small cylinder, this would result in a given pressure. By Pascal's Principle, this pressure would be the same in the larger cylinder, but since the larger cylinder has more area, the force emitted by the second cylinder would be greater. This is represented by rearranging the pressure formula P = F/A, to F = PA. The pressure stayed the same in the second cylinder, but Area was increased, resulting in a larger Force. The greater the differences in the areas of the cylinders, the greater the potential force output of the big cylinder. A hydraulic jack is simply two cylinders connected as described above.

An enclosed fluid under pressure exerts that pressure throughout its volume and against any surface containing it. That's called 'Pascal's Principle', and allows a hydraulic lift to generate large amounts of force from the application of a small Assume a small piston (one square inch area) applies a weight of 1 lbs. to a confined hydraulic fluid. That provides a pressure of 1 lbs. per square inch throughout the fluid. If another larger piston with an area of 10 square inches is in contact with the fluid, that piston will feel a force of 1 lbs/square inch x 10 square inches = 10 lbs

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Working Of Hydraulic Jack:-

So we can apply 1 lbs. to the small piston and get 10 lbs. of force to lift a heavy object with the large piston. Is this 'getting something for nothing'? Unfortunately, no. Just as a lever provides more force near the fulcrum in exchange for more distance further away, the hydraulic lift merely converts work (force x distance) at the smaller piston for the SAME work at the larger one. In the example, when the smaller piston moves a distance of 10 inches it displaces 10 cubic inch of fluid. That 10 cubic inch displaced at the 10 square inch piston moves it only 1 inch, so a small force and larger distance has been exchanged for a large force through a smaller distance. Hydraulic jacks have six main parts. These are the reservoir, pump, check valve, main cylinder, piston, and release valve. The reservoir holds hydraulic fluid. A pump will draw the fluid up and then create pressure on the down stroke as it pushes the fluid through the check valve. This valve allows the fluid to leave the reservoir and enter the main cylinder. In the main cylinder, the piston is forced up as the cylinder is filled with the fluid. When it is time to release the pressure and allow the piston to return to its starting position, the release valve is opened. This allows the fluid to return to the reservoir.

Show In Figure-

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In this system a reservoir and a system of valves has been added to Pascal's hydraulic lever to stroke a small cylinder or pump continuously and raise a large piston or an actuator a notch with each stroke. Diagram A shows an intake stroke. An outlet check valve closes by pressure under a load, and an inlet check valve opens so that liquid from the reservoir fills the pumping chamber. Diagram B shows the pump stroking downward. An inlet check valve closes by pressure and an outlet valve opens. More liquid is pumped under a large piston to raise it. To lower a load, a third valve (needle valve) opens, which opens an area under a large piston to the reservoir. The load then pushes the piston down and forces the liquid into the reservoir.

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Hydraulic Sheet Bending 2018 Chapter-6 Parts of hydraulic jack

Parts Of Hydraulic Jack:    

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Gland (End Cap) Piston Road Cylinder Base Plate Hose Pipe

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Hydraulic Sheet Bending 2018 1 Parts Of Cylinder:1.1-Cylinder Barrel:The cylinder barrel is mostly a seamless thick walled forged pipe that must be machined internally. The cylinder barrel is ground and/or honed internally.

1.2-Cylinder Base Or Cap:In most hydraulic cylinders, the barrel and the bottom portion are welded together. This can damage the inside of the barrel if done poorly. Therefore, some cylinder designs have a screwed or flanged connection from the cylinder end cap to the barrel. In this type the barrel can be disassembled and repaired.

1.3-Cylinder Head:The cylinder head is sometimes connected to the barrel with a sort of a simple lock. In general, however, the connection is screwed or flanged. Flange connections are the best, but also the most expensive. A flange has to be welded to the pipe before machining. The advantage is that the connection is bolted and always simple to remove. For larger cylinder sizes, the disconnection of a screw with a diameter of 300 to 600 mm is a huge problem as well as the alignment during mounting.

2-Piston Rod:The piston rod is typically a hard chrome-plated piece of cold-rolled steel which attaches to the piston and extends from the cylinder through the rod-end head. In double rod-end cylinders, the actuator has a rod extending from both sides of the piston and out both ends of the barrel. The piston rod connects the hydraulic actuator to the machine component doing the work. This connection can be in the form of a machine thread or a mounting attachment, such as a rod-clevis or rod-eye. These mounting attachments can be threaded or welded to the piston rod or, in some cases, they are a machined part of the rod-end.

2.1:-Piston Rod Construction:The piston rod of an hydraulic cylinder operates both inside and outside the barrel, and consequently both in and out of the hydraulic fluid and surrounding atmosphere.

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Hydraulic Sheet Bending 2018 Smooth and hard surfaces are desirable on the outer diameter of the piston rod and slide rings for proper sealing. Corrosion resistance is also advantageous. A chromium layer may often be applied on the outer surfaces of these parts. However, chromium layers may be porous, thereby attracting moisture and eventually causing oxidation. In harsh marine environments, the steel is often treated with both a nickel layer and a chromium layer. Often 40 to 150 micrometer thick layers are applied. Sometimes solid stainless steel rods are used. High quality stainless steel such as AISI 316 may be used for low stress applications. Other stainless steels such as AISI 431 may also be used where there are higher stresses, but lower corrosion concerns.

2.1.2:-Ceramic Coatings:Due to shortcomings of metallic materials, ceramic coatings were developed. Initially ceramic protection schemes seemed ideal, but porosity was higher than projected. Recently the corrosion resistant semi ceramic Lunac2+ coatings were introduced. These hard coatings are non porous and do not suffer from high brittleness.

2.1.3:-Length:Piston rods are generally available in lengths which are cut to suit the application. As the common rods have a soft or mild steel core, their ends can be welded or machined for a screw thread.

3:-Gland (End Cap):The cylinder head is fitted with seals to prevent the pressurized oil from leaking past the interface between the rod and the head. This area is called the rod gland. It often has another seal called a rod wiper which prevents contaminants from entering the cylinder when the extended rod retracts back into the cylinder. The rod gland also has a rod wear ring. This wear ring acts as a liner bearing to support the weight of the piston rod and guides it as it passes back and forth through the rod gland. In some cases, especially in small hydraulic cylinders, the rod gland and the rod wear ring are made from a single integral machined part.

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Hydraulic Sheet Bending 2018 Chapter-7

Conclusions

The capacity of the jack was not affected by adopting the change. 2. The fluid could flow from the reservoir to piston in a negligible time difference as compared to the previous case where pipe was not attached. 3. The jack was working smooth in horizontal position. 4. Less maintenance was required. 5. The change adopted was economical. Hence, the modified jack can be used anywhere without any limitations whatsoever. With a little change, that was quite economic and viable, one can attain proper working of the jack when kept horizontally. This new finding can find various applications in the field of engineering and can help to tailor the need for a new horizontal bottle jack. Object lifting jacks are the ideal product to push, pull, lift, lower and position loads of anything from a couple of kilograms to hundreds of tones. The need has long existed for an improved portable jack for automotive vehicles. it is highly desirable that a jack become available that can be operated alternatively from inside the vehicle or from a location of safety off the road on which the vehicle is located. Such a jack should be light enough and be compact enough so that it can be stored in an automobile trunk, can be lifted up and carried by most adult’s touts position of use, and yet be capable of lifting a wheel of a 4000- 5000-pound vehicle off the ground. Further, it should be stable and easily controllable by a switch so that jacking can be done from a position of safety. It should be easily movable either to a position underneath the axle of the vehicle or some other reinforced support surface designed to be engaged by a jack. Thus, the product has been developed considering all the above requirements. This particular design of motorized automated object lifting jack will prove to be beneficial in lifting and lowering of heavy loads.

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Hydraulic Sheet Bending 2018

ASSEMBLY AND DISASSEMBLY PROCESS The jack assembly is portable , self-contained unit with a single speed manually operated pumpat the lift unit consisting of three rams and on extension screw or cased within an anchoredcylinder mounted on the base .A stamped shell enclosed the ram and cylinder to form the fluidreservoir. 6.1 Assembly procedure The following steps will help us to assemble the hydraulic bottle jack. First put all components of HBJ in order pair and identify the dimension of allcomponents. Put the base on the on the flat table. Assemble the cylinder with the base together with the base plate. Assemble the reservoir to base together with sealing part. Insert O-ring and seal of nut to piston. Assemble piston to the piston. Assemble nut to piston. Insert adjusting screw and adjusting screw socket to piston road to get ram. Assemble O-ring (pump, plunger). Assemble plunger, spring bolt, short pin, link plate, and swing socket. Assemble oil fill plug, pin, release valve seal, boll, and spring with base. Install rubber handle holder onto the top nut & slide down ward until it rests upon thereservoir of the jack.

FINALLY assemble the handle section by lining up the spring detent in the rubber gripsection with the slot in the other section. 6.2 F T C Sangola

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Hydraulic Sheet Bending 2018 Disassembly procedure Steps; Clean table (keep the work area clean and well it) Use manual. Open the jack base. Drain the hydraulic oil. Open the bottle jack unit. Safely over load the check valve. Disassemble the plunger.8. Clean the bottle jack unit passage ways. Release the valves (O-ring). Check valves & safety over load valve. Disassemble the ram seal.

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Hydraulic Sheet Bending 2018 Chapter-8

Application

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Dismantling of old tanks .

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Repair to tank foundation .

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Building of field erected storage tanks .

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Repair or replacement of tank bottom plate.

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Increasing tank capacity by adding shell rings or courses .

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Erection of other circular structures such as reactor shields in nuclear power stations, etc.

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Hydraulic Sheet Bending 2018

Adv/Dis-Adv

Advantages

 Ease and accuracy of control: By the use of simple levers and push buttons, the operator of a hydraulic system can easily start, stop, speed up and slow down.  Multiplication of force: A fluid power system (without using cumbersome gears, pulleys and levers) can multiply forces simply and efficiently from a fraction of a pound, to several hundred tons of output.  Constant force and torque: Only fluid power systems are capable of providing a constant torque or force regardless of speed changes. 

Simple, safe and economical: In general, hydraulic systems use fewer moving parts in comparison with mechanical and electrical systems. Thus they become simpler and easier to maintain.

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Hydraulic Sheet Bending 2018

Dis-Advantages

 If there is thin rock or thin hard soil layer at the end of pile which is pressed, then it will result in errors during erection.  Because of hydraulic jacking systems has weight about 70 tons and the ground is not same with its bearing capacity, then this condition will lead to position of this tool to be tilted even fallen. This condition would be dangerous to the safety of workers.  Mobilization of this system is difficult especially in soft area or muddy area (usually in the soil deposits area).  The movement of Hydraulic Jacking System tool is slow, so the moving process need long time especially for distance of one pile driving point to other point is relatively far.

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Hydraulic Sheet Bending 2018 Chapter-9 Referances 

M. Weck: Werkzeugmaschinen Maschinenarten und Anwendungsbereiche (VDIBuchSpringer Vieweg Verlag, 6. Aufl. 2005 (2. August 2005), ISBN 3540225048



George William Sutcliffe (1895), Steam power and mill work principles and modern practice, Whittaker & Co., p. 828, The bottle-jack is exceedingly firm and safe for short vertical lifts, but is not convenient for pushing in a horizontal or oblique direction.



Jump up^ John Norman (2009), Fire Department Special Operations, Fire Engineering Books, p. 51, ISBN 978-1-59370-193-2



Jump up^ "Detroit Listening Post". Popular Mechanics. 132 (4): 44. ISSN 00324558. Retrieved 9 June 2017.



Jump up^ "Lifting Bag and Poppet Riveter Repair "Forts"". Popular Mechanics. 81 (1): 26. ISSN 0032-4558. Retrieved 9 June 2017.



Jump up^ "Pneumatic Lifting Bags". Windsor Fire & Rescue Services. Archived from the originalon 28 December 2011. Retrieved 6 October 2013

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