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Experiment.php
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<!DOCTYPE HTML public "-w3c//dtd//xhtml 1.0 transitional//en" "http://www.w3.org/tr/xhtml1/dtd/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<title>Virtual Lab-Dayalbagh Educational Institute</title>
<link rel="shortcut icon" type="image/x-icon" href="images/icon.ico">
<link href="css/main.css" rel="stylesheet" type="text/css">
<link href="css/dropdown.css" media="all" rel="stylesheet" type="text/css" />
<link href="css/advanced.css" media="all" rel="stylesheet" type="text/css" />
</head>
<body id="draggingDisabled" bgcolor="#FFFFFF">
<div id="header_main"></div>
<div id="header">
<ul class="dropdown dropdown-horizontal">
<?php
ini_set("display_errors","Off");
include("mainmenu.php");
?>
</ul></div>
<div><center>
<?php
$value = $_SERVER['QUERY_STRING'];
$plist=array_pop( explode('/', $value) );
print <<<EOQ
<iframe width="1020" height="600" src=$value?rel=0&autoplay=1&loop=1&playlist=$plist frameborder="0" allowfullscreen></iframe>
EOQ;
if(stristr($value,BptbUcB14wg))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
The given video depicts the motion and kinematics of the gravity drop forge hammer. Here we can visualise the reciprocating nature of the upper die which itself is connected with links like piston and ram, moving in an upward and downward direction repeatedly at a constant acceleration which is none other than the gravity pull of the earth. The rollers are placed in order to guide the long moving shaft connecting ram to move with the to and fro motion easily without being buckled. The billet is placed in the die cavity of the lower die that remains stationary.
Here in this process the energy required for the deformation of the billet i.e. the strain energy is been supplied by the kinetic energy of the moving hammer which itself gets that energy due its potential energy, by making the hammer to fall from the certain height. The effect of such a tremendous force will be that, the billet will tend to deform rapidly with the decrease of its height and subsequent increase in its cross-sectional area at each stroke of the ram. The process is repeated till the desired shape is obtained.
</td></tr></table>
<?php
}elseif(stristr($value,_tAUqDFzUEc))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
The given video depicts the detailed parts description and working of a gravity drop hammer. On the left side of the screen we can visualize various components of the gravity drop hammer. It includes the upper die assembly consisting of the board which is connected to the ram where the upper die is mounted, the forging stock at the centre and finally the lower die mounted on the anvil. The rollers are placed in order to guide the long moving shaft connecting ram to move with the to and fro motion easily without getting buckled up.
Whereas on the right hand of the screen we can visualise the kinematics of the upper die assembly which is moving in up and down directions repeatedly. Here the energy required for the deformation of the billet i.e. the strain energy is been supplied by the kinetic energy of the moving hammer which itself gets that energy due to its potential, by making the hammer to fall from the certain height.
The effect of such a tremendous force of the upper die would be that, the billet will tend to deform rapidly with the decrease in its height and subsequent increase of the cross-sectional area at each stroke of the ram. The process is repeated till the desired shape is obtained.
</td></tr></table>
<?php
}elseif(stristr($value,x_oEQGbS1ns))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
A hydraulic press is a device in which a large compressive force is exerted on the larger of the two pistons in a pair of hydraulically coupled cylinders by means of the relatively low force been applied to the smaller piston. The working of the machine is based on the Pascal’s law. A hydraulic press consists of frame with two or four columns, pistons, cylinders, rams and hydraulic pumps driven by electric motors . In the given video we see that the two sections, with left one depicting the various components of the hydraulic press whereas the right one depicting the working of the hydraulic press.
In the left side we see the hydraulic press consists of parts like the main cylinder with the two pipes at the upper and lower end of it, the piston, shaft and the ram assembly and also the ram guide. The working fluid is the water itself which is kept in cylinders. The right side of the screen shows the working of the hydraulic press, here we can see the piston which is been kept inside the hydraulically filled cylinder is been allowed to move to and fro in the vertical direction by the action of the hydraulic force which is been applied by incoming pressurised water. Initially at the downward stroke of the piston the water
is been pressurised through the upper pipe into the cylinder and during this stroke the work-piece is been pressed hydraulically with the constant pressure making it to deform in a continuous material flow manner. Whereas at the upward stroke(i.e. at the retrieval stroke) the water is been pressurised through the lower pipe into the cylinder or is withdrawn through the upper pipe only.
</td></tr></table>
<?php
}elseif(stristr($value,dLvVI9C3ieg))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
A hydraulic press is a device in which a large compressive force is exerted on the larger of the two pistons in a pair of hydraulically coupled cylinders by means of the relatively low force been applied to the smaller piston. The working of the machine is based on the Pascal’s law. A hydraulic press consists of frame with two or four columns, pistons, cylinders, rams and hydraulic pumps driven by electric motors. The hydraulic press are made according to the various product and process requirements. One of them is shown in this video. In the given video we see that the two sections, with left one depicting the various components of the hydraulic press whereas the right one depicting the working of the hydraulic press.
In the left side we see the hydraulic press consists of various components which include the hydraulic cylinder which is mounted on the top of the frame, inside the frame there are various components which include the ram connected to the punch and the work-piece which is to be shaped, and at the lower end there is the base. The working fluid is the water itself which is kept in cylinders. The right side of the screen shows the working of the hydraulic press, here we can see the piston which is been kept inside the hydraulically filled cylinder is been allowed to move to and fro in the vertical direction by the action of the hydraulic force which is been applied by incoming pressurised water. Initially at the downward
stroke of the piston the water is been pressurised through the upper pipe into the cylinder and during this stroke the work-piece is been pressed hydraulically with the constant pressure making it to deform in a continuous manner. Whereas at the upward stroke (i.e. at the retrieval stroke) the water is been pressurised through the lower pipe into the cylinder or is withdrawn through the upper pipe only.
</td></tr></table>
<?php
}elseif(stristr($value,j0k3epb7lgc))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
The following video shows the working of the hydraulic press consisting of the ram connected with the upper die. The working fluid used in the hydraulic press is water offcourse. The upper die is moved by the action of the pressurised water which flows in and out of the main hydraulic cylinder through the upper and bottom pipes in the cylinder. Initially at the downward stroke of the piston the water is been pressurised through the upper pipe into the cylinder and during this stroke the work-piece is been pressed hydraulically with the constant pressure between the set of the upper and the lower die, making it to take the shape of the cavity made in between these two dies. The upper die is made to restore its initial position by making the water to flow into the cylinder in a pressurised manner into the lower pipe.
</td></tr></table>
<?php
}elseif(stristr($value,ZbmN0brpn3w))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
The knuckle joint press is one of the form of the continuous forging presses. Here in this given video we can see that the screen is split into two parts the left side shows the various components of the knuckle joint press whereas the right side shows the working of the knuckle joint press. In the left side of the screen we can see the various components of the knuckle joint press, the components include the driving rotating shaft connected with link 1 (shown in the red colour), which is connected to another fully movable link 2 (shown in the green colour), and this link is connected to 3<sup>rd</sup> link (shown in the yellow colour) which is fixed at one of its end, this link is further connected with the 4<sup>th</sup> and final link (which is shown in the blue colour) whose another end is connected to the ram (also acting as a link) whose vertical motion is guided by the cylinder walls.
In the right side of the screen we can see that how the kinematics of these inter-connected links look like while in motion. As the link number 1 is moved by the rotating shaft the link 2, link 3, and link 4 are also follow the motion within their prescribed path of motion as constrained by their linkage state. The link4 (blue one) gives the motion to the ram link which is moved to and fro into the cylinder and its motion is been guided by the cylinder walls. This type of forging technique is quite faster as comparison to other techniques in producing the components but with the drawback that it could not apply that much of the pressing force as compared to others.
</td></tr></table>
<?php
}elseif(stristr($value,ruSKX9H8790))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
Mechanical presses are stroke limited ones. They are of either the crank or the eccentric type, with speeds varying from a maximum at the centre of the stroke to zero at the bottom. In the given video we can see that the two sections, with left one depicting the various components of the mechanical press whereas the right one depicting the working of the mechanical press. In the left side of the screen we can see the various components of the mechanical press, the parts include the huge flywheel with the eccentric shaft connected to it, the connecting rod connecting the eccentric shaft with the ram or the slide, the frame mounted on top of the table which contains the ram into it. The right side of the screen shows how the kinematics of such a linkage type looks like.
The rotating motion of the big flywheel is been transmitted to the reciprocating motion of the ram/slide by connecting in between them the connecting rod. The ram moves to and fro in the vertical direction inside the boundaries of the frame with the workpiece kept at the bottom of the frame and at the top of the table which is been compressed and deformed with each successive blows of the mechanical press slowly and gradually, up until it takes the required shape and size. Here the work-piece is reduced in its height whereas gets increased in its cross-sectional area. The force available for deforming work-piece depends upon the stroke position and becomes extremely large at the bottom-dead-centre position; thus, proper setup is essential to avoid breaking the dies or other equipment.
</td></tr></table>
<?php
}elseif(stristr($value,ZXEbYaEn99E))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
The screw presses derive their energy from a flywheel. The forging load is transmitted through a vertical screw. These presses are energy limited and can be used for many forging operations. They are particularly suitable for producing small quantities, for parts requiring precision (such as turbine blades), and for control of ram speed. In the given video we can see that the two sections of the screen, with left one section depicting the various components of the screw press whereas the right one depicting the working of the screw press. In the left side of the screen we can see the components like the driving wheel, the driven flywheel, the screwed shaft connected to the flywheel, the screwed stationary housing connected with the main cylinder and finally the ram connected with the screwed shaft in the centre of the screen.
The right side of the screen shows the kinematics of this process in action i.e. the downward stroke of the ram taking place. As the driving wheel is rotated by the subsequent power drive, the flywheel too gets rotated with its axis perpendicular to the axis of the driving wheel through the action of the frictional force acting in between the wheels in contact. The flywheel not only rotates about its axis but also translates up and down within the driving wheel limits. This action is possible due to the screw type of linkage between the externally threaded shaft connected to the flywheel and the internally threaded stationary housing mounted within cylinder grooves. This motion is been transmitted to the ram which is responsible for deforming the kept work-piece over the table by compressing it till it attains the required shape and size.
</td></tr></table>
<?php
}elseif(stristr($value,"2_pDKRurJ9U"))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
Cold extrusion is the general term often used to denote a combination of processes, such as direct and indirect extrusion and forging. Many materials can be extruded into various configurations, with the billet either at the room temperature or at the temperature of a few hundred degrees. Extrusion process can be defined as the metal forming process which is used to form the product with the fix cross sectional profile. A material is punched onto the die of the desired cross section. In the given video we can see the two sections of the screen, in the left side we can see the various components involved in extrusion process which includes the moving punch, work-piece and the lower fixed die and in the right side we can see the movement of the punch within the lower die cavity. Through this process we will attain the work-piece with increase in the length and with decreased cross-sectional area.
</td></tr></table>
<?php
}elseif(stristr($value,m8zJBMq9kLs))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
Extrusion process can be defined as the metal forming process which is used to form the product with the fix cross sectional profile. A material is punched onto the die of the desired cross section. Extrusion process can be divided into two categories: direct extrusion and indirect extrusion. Indirect extrusion can also be termed as backward or reversed extrusion. In case of indirect extrusion a die placed in hollow stem moves in relationship with the hollow container, however there is no such relative displacement between container and the billet. The indirect extrusion process is marked by the absence of friction between the container and the billet. In the given video there is friction of various parts of indirect extrusion process and its working model. In the left side figure there is die, punch or ram assembly.
The die contain the passage for the movement of hot billet and punch under very high pressure. There are two punches placed inside the die. First punch is placed at the top and is movable in nature, while the other punch is placed at the bottom and is static in nature. It prevents the movement of hot billet towards the downward direction . The upper punch moves downward and compresses the billet. The billet is forced to move out between the gap between the punch and the die in opposite direction to the motion of the die as shown in the figure. In the right hand side one can see the working model of the extrusion process . The hot billet is fixed at the chamber at the top after filling the punch presses the workpiece with very high pressure. As a result the billet is forced to flow out plastically between the gaps between the upper die and the die opposite to the direction of motion of the punch.
</td></tr></table>
<?php
}elseif(stristr($value,kRxV4D3GaCE))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
In direct extrusion process, we use the forward extrusion process in which the ram is connected with the mandrel. The mandrel is the object which is used to shape the internal cavity of the final product formed through metal forming process. In this extrusion process we see that the workpiece moves along with the mandrel or the ram such that relative velocity between the deformed workpiece and the mandrel is zero finally until the required shape is produced. In the left side of the screen we can see that the various components of the direct extrusion process with the mandrel, the components includes the ram connected with mandrel, the container acting as guide to the ram motion, the workpiece which is to be deformed and the final shaped workpiece. The right side of the screen shows the working of such process.
Here the ram connected with mandrel moves to and fro in the vertical direction all along the length of the container up until the final point of its stroke in the container. As the mandrel touches the workpiece in its axial point the workpiece starts to deform all along its length making the material to elongate longitudinally whereas it reduces in its cross-section, with its grains becoming smaller and smaller and also linearly arranged along its length thus increasing its longitudinal strength.
</td></tr></table>
<?php
}elseif(stristr($value,hMt1EuxNZ68))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
Direct extrusion, also known as forward extrusion, is the most common extrusion process. It works by placing the billet in a heavy walled container with the container liners present. The billet is pushed through the die by a ram or screw. There is a reusable dummy block between the ram and the billet to keep them separated. The major disadvantage of this process is that the force required to extrude the billet is greater than that needed in the indirect extrusion process because of the frictional forces introduced by the need for the billet to travel the entire length of the container. Because of this the greatest force required is at the beginning of process and slowly decreases as the billet is used up. At the end of the billet the force greatly increases because the billet is thin and the material must flow radially to exit the die. The end of the billet (called the butt end) is not used for this reason.
In the following video we can see that in the left side of the screen there are various components involved in the extrusion process which includes the pressing stem meant for forcing the dummy block against the work-piece, the initial work-piece before deformation, the cylinder walls protected with the cylinder liner inside them, the lower die block to shape up the cross section of the final extruded component, the die back up to prevent movement of the lower die. The right side of the screen shows the working of this technique. As the pressing stem is moved in downward direction the dummy block compresses the work-piece and force it move out from the smaller orifice of the lower die block with continuous and uniform force. Due to the sudden change in the cross section of the work-piece the forces acting on the lower die is higher, so it is needed to be backed up with the another block. The final component produced will be of shorter and axi-symmetric cross-section.
</td></tr></table>
<?php
}elseif(stristr($value,AJXO4ayKwjA))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
Because the hydrostatic pressure increases the ductility of the material, brittle materials can be extruded successfully through this method. Hydrostatic extrusion is generally carried out at the room temperature, typically using vegetable oils as the fluid, particularly castor oil because it is a good lubricant and its viscosity is not influenced significantly by the pressure. The process must be carried out in a sealed cylinder to contain the hydrostatic medium.
In the following video we can see that in the left side of the screen there are various components involved in the hydrostatic extrusion process which includes the working fluid which is been pressed by some piston of the press, this fluid pressurises the pressing stem meant for forcing the punch against the work-piece in the cylinder of smaller cross sectional area where the initial work-piece (i.e. the aluminium bar) is kept with the outer diameter equal to the internal diameter of the cylinder bore in that section, the pressing tool to shape up the cross section of the final extruded component. The right side of the screen shows the working of this technique. As the pressing stem is been moved by the hydraulic pressure action which is been applied by the pressurized fluid, it moves in the downward direction as shown here in the video, the pressing stem with the punch forces the work-piece all along the set bore diameter of the pressing tool, thus decreasing its cross-sectional area to good extent with application of the uniform force all along the punch travel throughout its length of the stroke.
</td></tr></table>
<?php
}elseif(stristr($value,ovxL0Vl8vmA))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
In direct extrusion process, we use the forward cold extrusion process for the production of the elongated final work-piece in its length whereas with decreased outer diameter. In this extrusion process we see that the work-piece moves along with the ram such that relative velocity between the deformed work-piece and the ram is zero finally until the required shape is produced. In the left side of the screen we can see that the various components of the direct extrusion process, the components includes the ram, the container, the work-piece which is to be deformed, the lower die and the final shaped work-piece. The right side of the screen shows the working of such process. Here the ram reciprocates to and fro in the vertical axial direction all along the length of the container up until the final point of its stroke in the container. As the work-piece is moved all along the tapered lower die, it gradually is been shaped in such a way that its length increases and in compensation its cross- sectional area to be reduced to the outer diameter equal to the internal diameter of the lower die.
</td></tr></table>
<?php
}elseif(stristr($value,"9AWa9yAze4U"))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
In the hydrostatic extrusion process the billet is completely surrounded by a pressurized liquid, except where the billet contacts the die. This process can be done hot, warm, or cold, however the temperature is limited by the stability of the fluid used. The pressure in the chamber transmits some of the fluid to the die surfaces, thus significantly reducing friction and forces. Because the hydrostatic pressure increases the ductility of the material, brittle materials can be extruded successfully through this method. Hydrostatic extrusion is generally carried out at the room temperature , typically using vegetable oils as the fluid, particularly castor oil because it is a good lubricant and its viscosity is not influenced significantly by the pressure. The process must be carried out in a sealed cylinder to contain the hydrostatic medium. The fluid can be pressurized two ways:<br/>
1. Constant-rate extrusion: A ram or plunger is used to pressurize the fluid inside the container.<br/>
2. Constant-pressure extrusion: A pump is used, possibly with a pressure intensifier, to pressurize the fluid, which is then pumped to the container.<br/>
In the following video we can see that in the left side of the screen there are various components involved in the hydrostatic extrusion process which includes the pressing stem meant for forcing the upper die block against the work-piece, the initial work-piece before deformation, the cylinder containing the working fluid with the seals all along its boundary to prevent the leakage of the fluid, the lower die block to shape up the cross section of the final extruded component, the die back up to prevent movement of the lower die. The right side of the screen shows the working of this technique. As the pressing stem is moved in downward direction the liquid in the chamber gets compressed and pressurised hence it enables the work-piece to get compressed all along its exposed surface and forces it to pass through the lower die orifice with continuous and uniform force.
</td></tr></table>
<?php
}elseif(stristr($value,bTVk8lCvy5k))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
In indirect extrusion process, the die moves toward the billet; thus, except at the die, there is no relative motion at the billet container interface. This process is specially advantageous for materials with high billet-container friction. Here one can see the hollow ram or die forces against the stationary work-piece which has been backed up the flat end of the upper die. This operation is marked by no relative displacement between the containing die and the billet, so we see there is no friction involved between them, which greatly improves the external surface finish of the finished product. However, one has to remove the lower hollow die that has been pierced upwards into the billet regarding extrusion of the part which sometimes gets stuck to the billet part due to certain plastic deformation, also making this process discontinuous.
Here in this video one can see on the left side of the screen the various components involved in this process, they are the cylindrical container meant for enclosing all the other parts, the work-piece been held up against the gravity by the ram action in the cylindrical container, the lower die with the internal bore which is backed up the hollow ram for its upward motion. The right side video shows the movement of this hollow die and hollow ram in the upward and downward direction to and fro into the cylindrical bore of the container.
</td></tr></table>
<?php
}elseif(stristr($value,Tjnf467rPSo))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
In Indirect extrusion, also known as backwards extrusion, the billet and container move together while the die is stationary. The die is held in place by a "stem" which has to be longer than the container length. The maximum length of the extrusion is ultimately dictated by the column strength of the stem.This process is specially advantageous for materials with high billet-container friction.
Here one can see the hollow ram or die forces against the stationary work-piece which has been backed up the flat end of the upper die. This operation is marked by no relative displacement between the containing die and the billet, so we see there is no friction involved between them, which greatly improves the external surface finish of the finished product.
However, one has to remove the lower hollow die that has been pierced upwards into the billet regarding extrusion of the part which sometimes gets stuck to the billet part due to certain plastic deformation, also making this process discontinuous.
Here in this video one can see on the left side of the screen the various components involved in this process, they are the cylindrical container meant for enclosing all the other parts, the work-piece been held up against the gravity by the ram action in the cylindrical container and the lower ram.
The right side video shows the movement of this solid ram in the upward and downward direction to and fro into the cylindrical bore of the container. This ram looks like piercing the work-piece all through its upward movement but it is not the actual case, here the work-piece is been deformed with its material flowing outwards from its central axis and downwards as and when they find the suitable space for the flow to take place within the cylindrical cavity provided as shown in the following video.
</td></tr></table>
<?php
}elseif(stristr($value,hgYPVerfk2Y))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
In indirect extrusion process, one can see the hollow ram or die forces against the stationary work-piece which has been backed up the flat end of the upper die. This operation is marked by no relative displacement between the containing die and the billet, so we see there is no friction involved between them, which greatly improves the external surface finish of the finished product. Because the billet moves with the container the frictional forces are eliminated. This leads to the following advantages:
<br/>1. A 25 to 30% reduction of friction, which allows for extruding larger billets, increasing speed, and an increased ability to extrude smaller cross-sections.
<br/>2. There is less of a tendency for extrusions to crack because there is no heat formed from friction.<br/>
3. The container liner will last longer due to less wear.<br/>
4. The billet is used more uniformly so extrusion defects and coarse grained peripherals zones are less likely.<br/>
However, one has to remove the lower hollow die that has been pierced upwards into the billet regarding extrusion of the part which sometimes gets stuck to the billet part due to certain plastic deformation, also making this process discontinuous. One cannot be able to obtain the longer continuous extruded part with this technique because one is suppose need to design the hollow die of good strength to bear any such bending regarding its lengthier size that is to be pressed upwards all the way into the cavity of the container.
</td></tr></table>
<?php
}elseif(stristr($value,wqL7wWPYPiw))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
Stamping includes a variety of sheet-metal forming manufacturing processes, such as punching using a machine press or stamping press, embossing, and coining. In this video, one could view the upper die with word "D.E.I. LAB" embossed over the die. During the stamping operation a sheet metal is placed between the dies.
The upper die presses the sheet metal between the dies which deforms the sheet metal and stamps the embossed words over the sheet metal. On the left hand side, one could see the temperature scale from where the temperature variations over the sheet metal can be visualized. The final stamped sheet can be seen at the end of the video.
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<?php
}elseif(stristr($value,Barshear))
{
?>
<table border="2" color="#ffffff" width="1020" style="background-color: white;">
<tr><td style="font-size: 1.2em; padding:5px; line-height:20px;">
Bar shearing is a process in which the billets of desired length are sheared off from a long bar. The picture shows the initial and the final sheared billet obtained. Now this is the bar shearing setup which shows top shear dies and the bottom shear dies. The dies blue and purple are stationary while green and yellow are movable.
The press used here imparts a downward force on green die and the yellow die is constrained to move when force on it reaches above 5 TON or more. This is the simulation of the bar shearing process. On the top right is shown the normal stress distribution during the shearing process. In the bottom right one can see the distribution of force on the green shear die. The maximum force evolved is 8.1 tonne.
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<?php
}
//Opening file to get counter value
$fp = fopen ("counter.txt", "r");
$count_number = fread ($fp, filesize ("counter.txt"));
fclose($fp);
$counter = (int)($count_number) + 1;
$count_number = (string)($counter);
$fp = fopen ("counter.txt", "w");
fwrite ($fp, $count_number);
fclose($fp);
?>
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