ABSTRACTIn this project, our objective to discuss the concept of physics, MAGNETISM, involved in MAGNETIC IMPURITY SEPARATOR CONVEYOR BELT. In this project:-

1. In the first section, we describe MAGNETISM and all other terminologies based on magnetism.

2. In the second section, we state the components used in our working model and give an overview about the same.3. In the third section, we discuss different types of components used in our project in detail, material used in their making, configuration of the components and theory based on the same.4. In the fourth section, we discuss the possible modifications in our project, to make it more versatile, accurate and at the same time, efficient.5. In the fifth and last section, we discuss the applications of our projects basic mechanism, its present use and future research that can be done and applied in our daily lives.

We hope we have lived upto the expectations and if there are any sort of mistakes or errors, we apologise for it.

1. IntroductionMagnetismis a class of physical phenomenon that includes forces exerted bya magneton other magnets. It has its original sources in electric currents and the fundamentalmagnetic momentsof elementary particles. These give rise to amagnetic fieldthat acts on other currents and moments. All materials are influenced to some extent by a magnetic field. The strongest effect is on permanent magnets, which have relentless magnetic moments caused byferromagnetism. Most materials do not have permanent moments. Some are attracted to a magnetic field (paramagnetism); others are repulsed (diamagnetism); some have a much more intricate relationship with an applied magnetic field (spin glassbehaviour andantiferromagnetism). Substances that are minutely affected by magnetic fields are known asnon-magneticsubstances. They includecopper,aluminium,plastic, andgases.The magnetic state of a material depends on temperature and other variables such as pressure, applied magnetic field etc. so that a material may exhibit more than one form of magnetism depending on the above variables.

Fig.1.1: Horseshoe Magnet with its Magnetic Field

Magnetism, predominantly, arises from two sources:

1. Electric current.

2. Nuclear magnetic momentsof atomic nuclei. These moments are typically thousands of times smaller than the electrons' magnetic moments, so they are negligible in the context of the magnetization of materials but are very important in other contexts, particularly innuclear magnetic resonance(NMR) andmagnetic resonance imaging(MRI) techniques.1.1 MagnetA Magnet is a material or object that produces a magnetic field. This magnetic field is invisible but is responsible for the most notable property of a magnet: a force that pulls on other magnetic materials and attracts or repels other magnets.

A permanent magnet is one that stays magnetized. Materials which can be magnetized, which are also the ones that are strongly attracted to a magnet, are called ferromagnetic materials. These include iron, nickel, cobalt, some rare earth metals and few of their alloys, and some naturally occurring minerals like lodestone. The other type of magnet is an electromagnet, a coil of wire which acts as a magnet when an electric current passes through it, but stops being a magnet when the current is switched off. Mostly an electromagnet is wrapped around a core of ferromagnetic material like steel, which enhances the magnetic field produced by the coil. Permanent magnets are made from "hard" ferromagnetic materials which are designed to stay magnetized, while soft ferromagnetic materials like soft iron are attracted to a magnet but dont tend to stay magnetized for a long time.1.2 Types of Magnetism1.2.1 ParamagnetismIn a paramagnetic material there areunpaired electrons, i.e.atomicormolecular orbitalwith exactly one electron in them. This unpaired electron is free to align its magnetic moment in any direction. When an external magnetic field is applied, these magnetic moments will tend to align themselves in the same direction as the applied field, thus reinforcing it.

Without Magnetic Field With Magnetic FieldFig.1.2: Direction of Magnetic Moments in Paramagnetic materials

1.2.2 DiamagnetismDiamagnetism appears in all materials, and it is the tendency of a material to oppose an applied magnetic field, and therefore, to be repelled by the same magnetic field. However, in a material with paramagnetic properties (that is, with a tendency to enhance an external magnetic field), the paramagnetic behaviour dominates.Thus, despite its universal occurrence, diamagnetic behaviour is observed only in a purely diamagnetic material. 1.2.3 FerromagnetismA ferromagnetic substance, like a paramagnetic substance, has unpaired electrons. However, inadditionto the electrons intrinsic magnetic moment's affinity to be parallel to anapplied field, there is also a tendency for these magnetic moments to adjust parallel toeach otherto maintain a lowered-energy state. Thus, even in the absence of an applied field, the magnetic moments of the electrons in the material spontaneously line up parallel to one another.

Fig1.3: Direction of Magnetic Moments in Ferromagnetic materials1.2.4 AntiferromagnetismIn an antiferromagnet, unlike a ferromagnet, there is a tendency for the intrinsic magnetic moments of neighbouring valence electrons to align inoppositedirections. When all atoms are arranged in a substance so that each neighbouring valence electron is 'anti-aligned', the substance is antiferromagnetic. Antiferromagnets have a zero net magnetic moment, i.e. no field is produced by them. Antiferromagnets are less common and are mostly observed at low temperatures. In changing temperatures, antiferromagnets can be seen to show diamagnetic and ferrimagnetic properties.

Fig1.4: Direction of Magnetic Moments in Antiferromagnetic materials

1.2.5 FerrimagnetismLike ferromagnetism,ferrimagnetsretain their magnetization in the absence of a field. However, like antiferromagnets, neighbouring pairs of electron spins point in opposite directions. These two properties are not contradictory, because in the optimal geometrical arrangement, there is more magnetic moment from the sub lattice of electrons that point in one direction, than from the sub lattice that point in the opposite direction.

Fig1.3: Direction of Magnetic Moments in Ferrimagnetic materials2.0 Components Used

We have used the following components which have been used in our project, MAGNETIC IMPURITY SEPARATOR CONVEYOR SYSTEM. S.No.Component Specification

1.)Wooden base18x24 inches

2.)D.C. motor30rpm, 12-24V

3.)Step Down Transformer12012

4.)Bridge Rectifier(Quantity=1)

5.)Sandpaper beltApprox. 42 inch

6.)Coupling(Quantity=1)

7.)PulleyDia.=2 inch

Length=12cm

8.)Ball Bearings6001 (Quantity=4)

9.)Permanent Bar Magnet

2.1. Description of Components

1.) D.C. motor

A machine that converts D.C. power into electrical power is known as D.C. motor. In our project, we have used a 3 rpm, 12-24v supply dc motor. It is based on the principle that when a current carrying conductor is placed in the region of magnetic field, the conductor experiences a mechanical force whose direction is given by Flemings left hand rule. A D.C. motor consists of six basic parts field system, armature core, armature winding, commutator and brushes. In most DC motors the external magnetic field is produced by high-strength permanent magnets. The stator is the stationary part of the motor -this includes the motor casing, as well as permanent magnet pole pieces. The rotor is the rotatory part and rotates with respect to the stator.

2.) Transformer A transformer is a device that is used either for raising or lowering the voltage of an A.C. supply with corresponding increase or decrease in current. We have used a step down transformer (12012). It works on the principle of electromagnetic induction and consists of two windings primary and secondary. The voltage (V) whose magnitude is to be changed is applied to the primary. Depending upon the no. of turns in primary and secondary, Emf is induced in the secondary due to terminal voltage (V1) appear at the load. If V1>V then it is step-up transformer else if V>V1 then it is a step-down transformer.3.) Bridge rectifier

In bridge rectifier four diodes are connected in the form of Wheatstone bridge.During the positive half-cycle of the secondary voltage, diodes D2 and D3 are conducting and diodes D1 and D4 are non-conducting. Therefore, current flows through the secondary winding, diode D2, load resistor R and diode D3. During negative half-cycles of the secondary voltage, diodes D1 and D4 conduct, and the diodes D2 and D3 do not conduct. The current therefore flows through the secondary winding, diode D1, load resistor R and diode D4. In both cases, the current passes through the load resistor in the same direction. Therefore, a fluctuating, unidirectional voltage is developed across the load.

Fig.2.1: Bridge Rectifier

4.) Power supply

Transformer Rectifier Filter Voltage Output

Regulator Voltage

A.C. input

signal

Fig.2.2: Flow chart of conversion of A.C. to D.C.

We have included a circuit that converts ac voltage of mains into dc voltage. This part of the equipment is called Power Supply. In general, at the input of the power supply, there is a power transformer. It is followed by a diode circuit called Rectifier. The output of the rectifier goes to a smoothing filter, and then to a voltage regulator circuit.

5.) Sandpaper belt

In our project, we have used sandpaper belt as a conveyor (used for transportation purposes) of approximately 42inch in length. These belts are abrasive in nature and can also be used in sanding, grinding, deburring, blending, finishing and polishing applications. These belts are quite good at gripping purposes as well.

6.) Pulley

In our project, we have used two pulleys of 2 inch diameter and 12cm length. One of the pulley being magnetic in nature as it consist of permanent bar magnet which is used for removing the magnetic impurities from the material. The ends of the pulleys are made in lathe. Thus making the pulley magnetic in nature rather than attaching magnet pieces in the vicinity turned up to be an innovation in our project.

3.0 Components Used (In Detail)a.) Wooden Base

The project consists of a wooden base over which the whole setup is established. The measurement of the wooden base is 18 X 24 in length.

The wooden base consists of the sandpaper belt over the wooden support, the shaft, bearings, brush couplings, transformer, bridge rectifier , permanent magnets & motor of 30 rpm speed.

b.) Permanent Bar Magnet

Permanent bar magnet is a device which creates its own persistent magnetic field around it.

Everyday example is a refrigerator magnet that holds the note on the refrigerator door. Materials that can be easily magnetized and have strong magnetic effect is ferromagnetic material.

These type of permanent magnets also includes iron , nickel , cobalt and other rare alloys on the earth and some naturally occurring minerals like lodestone as well. Although the ferromagnetic and ferromagnetic materials are the only one which attracts the other substances.

Fig.3.1: Permanent Bar Magnet

c.) Bridge Rectifier

Bridge rectifier is the setup of four or more rectifiers attached for the polarity of input as well as the polarity of the output.

The bridge rectifier provides the full wave rectification and converts the alternating current into direct current.

The polarity of the output is same as that of the polarity of the input section in a bridge rectifier. The essential feature of a diode bridge is that the polarity of the output is the same regardless of the polarity at the input.

Fig.3.2: Bridge Rectifier

d.) Zener Diode

Zener diode is a diode which allows the current to pass in the forward direction just as it flows in an ideal diode but it also allows the current to pass through it in the opposite direction when it reaches to certain to certain level of current that is known as breakdown voltage the only the reverse current starts to flow. This breakdown voltage is also known as avalanche voltage, peak inverse voltage or zener voltage. The reverse breakdown voltage is because of electron quantum tunneling under high electric field strength known as zener effect.

The zener diode is the ideal device for the application like voltage stabilizer for low current devices and the generation for the reference voltage.Unless this current is limited by circuitry, the diode may be permanently damaged due to overheating. A Zener diode exhibits almost the same except properties; the device is specially designed so as to have a reduced breakdown voltage, the so-called Zener voltage.

Fig.3.3: Zener Diodee.) Motor of 30 R.P.M Speed

The 30 rpm and rating with 12V is basically used for robotics purposes but in this project the main function of this motor is to rotate the belt according to the direction being decided for it in a circular manner over its decided path.

This 30 rpm motor rotates 30 times along its path in 60 seconds and provides the major functioning of the whole setup.

This motor has the steel gears in the inner periphery and steel pinions as well to provide it a longer life and avoid the situation of wear and tear.

Nut and thread on the shaft to easily connect and internal and internal threaded shaft for easily connected it to the wheel.

The gears used in this motor is spur gear , total length of the motor is 46mm , the diameter of the motor is 36mm , the brushes used in the motor is made up of precious metal. The weight of the motor used in the setup is 105 grams and the shaft length is 25mm. The diameter of the shaft of the motor is 12mm

Thus it plays one of the major role in the starting of the whole setup and the rotation of the sandpaper belt.

f.) Sandpaper Belt

The setup consist of the sandpaper belt over which the impurities along with the pure material will move and the sandpaper will lead the impurities which are specifically the metal impurities to get removed when they reach to the particular end where the permanent magnet is attached. The sandpaper belt is very easily available as well as reasonable in prices as well and as a sample of any project its the best available thing.

The sand paper belt consist of the frictional part on its surface as well which is very important to hold the material so that it does not gets out of its movingtrack as well.

Thus the sandpaper belt plays an important role in the transfer of the material with its impurities and refining it well through the magnet by its circular rotation with the help of the motor of speed 30rpm.

Fig.3.4: Sandpaper beltg.) Bearing

The bearing is the part of the setup that is useful in the rotation of the pulley. The bearing is attached the both ends of the setup and the pulley rotates over it over which the sandpaper belt is present and thus the sandpaper belt also rotates along with it.

Fig.3.5: Ball Bearing

h.) Coupling

Coupling is the part of the setup which is used for the attachment of the permanent magnet pulley, connected to the 30 rpm motor, through a ball bearing.

The coupling thus helps in attachment and so the material with metallic impurity get removed quickly due to the effect of the magnetic field of the bar magnet in the setup.

Fig.3.6: Coupling4.0. IMPROVEMTS TO MAKE CONVEYOR BELT SEPERATOR EFFICENT AND VERSATILE

Since no project is perfect, there is always a scope of improvement. Here are some of the improvements that we recommend can make this project near to perfect, versatile, accurate, efficient, effective and economically feasible. Following are some of the techniques:-1. One way of improving the Conveyor Belt Magnetic Separator is by adding sensors on the side to it. For examples if we add a color sensor to it which detects the red color body and stops when it finds a red color body. It can be used for separating many impurities with the help of one machine only. It can further be improved by adding an arm i.e. it will throw the color impurity out.2. Moreover it can be improved by increasing the length of the belt and using leather belt instead of sand paper belt. By increasing the length we can put number of samples or impurity on the same belt which will save our time, and by using leather belt we can increase the life of the belt.3. Magnetic separators are used for many purposes, for example for removing tramp iron from coal, rock, food products and other nonmagnetic material. The magnetic separator comprises an endless belt conveyor having an upper and lower run and an electromagnet mounted there between. The magnetic material attracted by the magnet is carried off by the belt and discharged. 4. In order to reduce the size and weight of the magnet, it is desirable to operate it at high power rating and high efficiency. As the power consumed by the magnet results in the generation of heat, it is necessary to dissipate the heat produced in order to avoid damaging the magnet winding.Another type of conveyor belt magnetic separator could be given below:-It is an objective of the invention to provide an improved self-cleaning magnetic separator having means for effectively and efficiently cooling the magnet to permit it to operate with relatively high power input while maintaining a safe operating temperature.The nature, objects and advantages of the invention will be more fully understood from the following description and claims in conjunction with the accompanying drawings which show by way of example a preferred embodiment of the invention.

This invention relates to improvements in a conveyor belt magnetic separation system for increasing the recovery of magnetic ore from the feed material. The system includes a separator which has a magnetic head-pulley assembly mounted in one end of an endless belt conveyor loop. When the conveyor is run at high speeds some of the ore is thrown off the head-end of the belt instead of being retained on it by the magnetic pulley. Those ore particles that are retained are carried onto the lower flight of the belt from which they are dropped into an ore chute. To recover the magnetic portion of the "thrown" ore, an adjustable splitter is located outwardly of the pulley-head at a lower elevation than the belt. The splitter also directs these partially magnetic particles into the ore chute and the non-magnetics to a tailings chute. The improvements of the present invention increase the degree of separation by making the trajectory of thrown particles primarily a function of their magnetic content and eliminating other factors. The fine magnetic ore particles that lay on top of large non-magnetic particles are stratified to the bottom of the belt. Without the stratification, these fine magnetic particles would be lost to tailings with the large non-magnetic particles. The improvements include apparatus for vibrating the feed particles to stratify them by size, and apparatus for minimizing the depth of the feed layer by allowing it to progressively increase in width in the direction toward the magnetic head-pulley. Thus, a thin layer of feed stratified by size may be obtained so as to achieve better separation by magnetic attraction and trajectory at high belt speeds.

Brief Description Of The Drawings:-

FIG. 1 is a side elevation view of a magnetic head-pulley and an overhead magnetic drum separator incorporating improvements according to the instant invention.

FIG. 2 is a view taken at II--II of FIG. 1.

FIG. 3 is a partial top plan view of the conveyor belt of the separator shown in FIG. 1. Description

Referring to Figs. 1, 2 and 3, magnetic separation apparatus is shown, including a driven endless conveyor belt 10. A permanent-magnet, belt-head pulley 12 is located at the upper end of the loop. Particulate feed material, in our case magnetite ore, is delivered onto the belt by conventional devices (not shown). The feed is carried on the belt over head-pulley 12. At typical belt speeds, (400 rpm) strongly magnetic ore particles are held to the belt and are carried under the head-pulley to the lower conveyor flight. There, after passing the head-pulley 12 they drop off the belt into ore chute 14. Non-magnetic, gangue particles are not held to the belt and are thrown outwardly toward chute 16. Some of the less magnetic ore is also thrown off the belt outwardly of the head-pulley. An adjustable splitter 18 is used to separate magnetic ore from gangue since the two will have a different trajectory. An overhead magnet head-drum separator 20 may be used to lift larger strongly-magnetic ore particles from the belt and direct them to another ore chute 21. Drums of this type are readily available from Eriez Company. We use such apparatus to up-grade the magnetic content of feed for a rod mill which grinds the ore to finer size, after which it is further ground and magnetically concentrated and used to make pellets for blast furnace feed.

To further increase the effectiveness of separation of the ore from gangue at high belt speeds, we provide a series of rotatable idler rollers 22 abutting the underside of the top flight of belt 10. At least some of the rollers have 5/16" square keystock welded to their outer surface to provide projections for striking the belt as the rollers rotate, thus we refer to them as "bouncing idlers". The keystock bars are spaced at 90 locations around the roller surface and extend longitudinally parallel to the roller axis. It will be apparent that the size of the rollers as well as the size and number of keystock bars may be varied and selected according to the results obtained in any particular system. Moreover, other means of vibrating the particles should be considered within the scope of the invention, for example an alternating intermittent magnetic field may be provided to excite ore particles on the belt.

Flexible skirting 30 is provided for extending longitudinally along opposite side edges of the top flight of belt 10. This skirting may be rubber or similar material mounted in brackets 32 of well known type. The skirts are spaced apart so as to taper outwardly to greater width in the direction toward head-pulley 12 as shown in FIG. 3. Desirably the skirting material extends downwardly so as to engage belt 10 and lay inwardly facing the belt axis. Thus, as the particles bounce and stratify, in the apparatus shown, along with the belt 10 itself, they will not wedge under the skirting since it tapers outward. Moreover, wear of the belt and spillage of particles will be prevented. Again other means may be used to control and regulate the width and depth of the particle layer which will be apparent to those skilled in the art. For example, eccentric idlers or idlers of varying arc shape, or groups of idlers arranged in varying shapes may be provided to control belt shape, and thus the particle layer thickness and width.

These and other embodiments within the spirit and scope of the invention will readily be apparent to those skilled in the art and are intended to be covered by the following claims appended hereto.

This invention relates to apparatus for separating magnetic ore from gangue, and particularly to improvements in magnetic head-pulley separators.

The commonly used separator has a horizontal or an upwardly inclined belt conveyor with a magnetic head-pulley at its upper end. At normal conveyor speeds magnetic particles adhere to, and are carried on the belt to an ore chute under the head-pulley. Non-magnetic gangue particles are thrown off the conveyor into another chute outwardly of the head-pulley.

It has been shown that production can be increased by running the belt at increased speeds and also increase the efficiency of separation. The higher speed and resultant thinner layer of ore increases the chances for a clean and high capacity separation. Although some magnetic particles will be thrown off the conveyor with the gangue, they will have different trajectories than the gangue, due to their magnetic attraction to the head-pulley. Thus, a splitter device appropriately placed outwardly of the head-pulley, will direct "thrown" magnetic particles into the ore chute, while non-magnetic gangue particles will continue to be collected by the splitter. However, the degree of separation and recovery at higher speeds can be further improved. Other factors affect the magnetic separation of the particles, not just their magnetic ore content.

It is therefore a primary object of this invention to provide improvements in magnetic pulley-head separators, so as to obtain better separation and recovery of magnetic ore at higher than normal belt speeds.

The conventional magnetic pulley-head separator includes an endless conveyor belt loop, a magnetic head-pulley within one end of the loop, means for driving the conveyor, and a splitter device located outward of the head-pulley. The improvements of this invention include means for vibrating the particles in the feed layer on the belt so as to stratify them by size (coarse on top, fines on the bottom). Means also is provided to minimize the depth of the feed layer, to encourage stratification during vibration, by allowing the layer to progressively increase in width on the belt in the direction toward the magnetic head-pulley. This feature avoids the capture of ore particles under the belt skirting and wear on the belt. Preferably, the vibrating means comprises means for periodically striking the conveyor belt to set up vibrations in the particle feed layer. For example, one or more idler rollers having longitudinal bars spaced along their outer circumference may be used under the top flight of the belt to set up the vibrations therein. Flexible skirting may be used to control the width and minimize the depth of the particle layer

We claim:

1. In magnetic ore particles separating apparatus, said apparatus including belt conveyor means, said conveyor including at least one endless belt loop, a head-pulley mounted within said loop at one end thereof, said pulley having magnet means for attracting said ore particles, means for driving said conveyor, and a splitter device located downwardly from said head-pulley and aligned outwardly of said loop so as to effect separation of particles by differences in trajectory and magnetic susceptibility when thrown off the head-pulley end of said loop,

the improvement in said apparatus which comprises:

Means for periodically striking said conveyor at least one location of an upper flight of said belt intermediate said head-pulley and an opposite end thereof so as to effect stratification of said particles by size prior to their arrival at said head-pulley-end means for regulating the width of the layer of ore particles on said conveyor, said width tapering outwardly toward the side edges of said conveyor means in the direction toward the head-pulley, whereby, a thin layer of particles stratified by size is obtained at the head-pulley end of said conveyor, thus improving separation of magnetic from non-magnetic particles by differences in the trajectory and magnetic susceptibility thereof.

2. The apparatus of claim 1 wherein said striking means includes at least one idler roll abutting an underside of said upper flight of said belt, said roll having longitudinally extending protrusions at spaced locations on the outer periphery thereof for striking said belt.

3. The apparatus of claim 1 wherein said width regulating means includes spaced flexible skirting disposed above said conveyor, said skirting hanging downwardly to said conveyor and laying on the top surface of and facing inwardly toward the axis thereof.

5.0 PRESENT USE and FUTURE RESEARCH in CONVEYOR BELT5.1 Present UseMagnetic belt conveyors effectively convey the ferrous objects on high speed horizontal and inclined to vertical conveyor belts. Below the conveying belt there is a permanent or electromagnetic rail which attracts the ferrous objects to the belt. This magnetic attraction acts as a clamping force against the conveyor. This cause the ferrous objects to move with the belt and able to overcome any angle of incline or decline. Conveyors are available with different belt width.

Magnetic conveyor has wide applicability. They find their usage in the following industries:

Mining

Construction

Chemicals

Food

Cement5.2 Typical Applications

Manufactured in self cleaning with cross belt conveyor system, they automatically discard the tramp iron from the process.

Most effective for removal of tramp iron from materials carried over conveyors/ vibratory feeders or inclined planes.

Suitable for foundry, coal mines, cement work, food, chemical industries, domestic waste cycling plants, material processing etc.Some of its examples are as given below: C-SCAN GHF

Fig. 4.1: C-SCAN GHFC-SCAN GHF metal detectors are primarily used in the food industry mounted on conveyor belts, inclined slides or other product transport systems. They detect all magnetic and nonmagnetic metals, (ferrous, non-ferrous and stainless steel) regardless of where the contaminant is within the product.

ELS

Fig. 4.2: ELSThe single-layer, single-face ELS detector is used for examining individually packed products and bulk materials on a conveyor belt or a material chute, preferably with a low material height. It detects all magnetic and non-magnetic metal contaminations (steel, stainless steel, aluminium) even if enclosed in the product. On detection of metal, a signal device and a separation system can be activated or a signal can be sent to process controlling.

GLS

Fig. 4.3: GLSEnclosed-aperture tunnel metal detector installed in bonded-type conveyor belt systems for applications requiring higher scanning sensitivity.

PM

Fig. 4.4: PM For the separation of ferrous contaminants, plate magnets are installed in a continuous material flow above conveyor lines, in free fall, under chutes and slides, etc

Protection of Wood Finishing Equipment

Fig. 4.5: Finishing EquipmentMetal fragments such a broken drill bits may become embedded in wood as a result of production processes. Metal detectors are essential in order to safely remove such fragments before further steps such as profiling, milling and planning.Some of the other uses may be-

Amoving walkwayormoving sidewalk, is a slow moving conveyor mechanism that transports people across a horizontal or inclined plane over a short to medium distance.Moving walkways can be used by standing or walking on them. They are often installed in pairs, one for each direction. Some of other applications are as follows: Airports Museum exhibits

Now there are different kinds of conveyor belts that have been created for conveying different kinds of material available in PVC and rubber materials. The belt consistsof oneora lot oflayersof fabric.Severalbeltsgenerallymaterial handling havetwolayers associateunderlayerof fabricto givelinear strengthassociatedformreferred to asabodyand an over layer referred to asthe cover. Thebodyis commonlyawovenclothhaving a warp &woof.The foremostcommon bodymaterialsarea unitpolyester, nylon and cotton.The quiltis commonlynumerousrubber or plastic compoundsfixedby use of the belt. Coversaremade ofa lot ofexotic materials foruncommonapplicationslike polymerfor warmthor gum rubberoncetractionis crucial. Zoos Theme parks Theatre Public transport Urban areas

Theconveyeris employedas a carrying medium of a belt conveyor system (often shortened to belt conveyor). A belt conveyor system isan exampleof conveyor systems. A belt conveyor system consists of2or additionalpulleys (sometimesobservedas drums), withanendless loop of carrying medium - theconveyer- that rotatesconcerningthem. One oreachof the pulleysaredriven, moving the beltand somaterial on the belt forward. Thepoweredpulleyis known asthe drivepulley whereastheunpowered pulleys is termed astheidler pulley. Therearetwomain industrialcategoriesof belt conveyors; Thosegenerallymaterial handlinglikethose moving boxesonwithinaplantand bulk material handlinglikethoseaccustomed totransportmassivevolumes of resources and agricultural materials,likegrain, salt, coal, ore, sand, overburden andadditional. Skiing

Ski areas additionallyuse conveyor beltsto moveskiers uphill. Supermarkets

Storestypicallyhave conveyor belts at the check-out counterto movelookingthings.REFERENCESThe below links were used by us to complete our project. We have tried to our level best to avoid copying the exact content. Any errors committed are regretted.

http://www.wikipedia.org/magnetism.htm

Electronic devices and circuit by J.B.Gupta page no. 208 Principles of Electrical machines by V.K.Mehta page no. - 106 http://www.encyclobeamia.solarbotics.net/ http://www.google.com/patents

1