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INTRODUCTION

Vibrating tube conveyors are used to convey powders horizontally at a controlled rate in a totally

enclosed environment.Conveying action is gentle and quiet at low velocity with no moving partsin contact with the powder, resulting in virtually no degradation. Conveyors can be mounted on

isolation spring support bases .The metering of powders is sometimes done mechanically with

conveying equipment. Vibrating tube conveyors are able to process a variety of powders while

transferring them efficiently and safely. Each of the designs offer flexibility to custom fit theconveyor for your newly designed system or to integrate to an existing process. We offer a wide

range of conveying equipment, focusing on vibrating tube conveyors.

A conveyor system is a common piece of mechanical handling equipment that moves materials

from one location to another. Conveyors are especially useful in applications involving the

transportation of heavy or bulky materials. Conveyor systems allow quick and efficienttransportation for a wide variety of materials, which make them very popular in thematerial

handling andpackaging industries. Many kinds of conveying systems are available, and are usedaccording to the various needs of different industries. There are chain conveyors (floor andoverhead) as well. Chain conveyors consist of enclosed tracks, I-Beam, towline, power & free,

and hand pushed trolleys.

Conveyor systems are commonly used in many industries, including the automotive, agricultural,

computer, electronic, food processing,[4] aerospace, pharmaceutical, chemical, bottling and

canning, print finishing and packaging. Although a wide variety of materials can be conveyed,some of the most common include food items such as beans and nuts, bottles and cans,

automotive components, scrap metal, pills and powders, wood and furniture and grain and

animal feed. Many factors are important in the accurate selection of a conveyor system. It is

important to know how the conveyor system will be used beforehand. Some individual areas thatare helpful to consider are the required conveyor operations, such as transportation, accumulation

and sorting, the material sizes, weights and shapes and where the loading and pickup points need

to be.

TYPES OF CONVEYORS

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1. Chute Conveyor

The chute conveyor is one of the least expensive methods of conveying material. It is the

simplest example of gravity-operated conveyor. Chute conveyor is used to provide accumulation

in shipping areas; a spiral chute can be used to convey items between floors with minimum

amount of space required. While the chute conveyors are economical, the main limitation ofchute conveyors is the lack of control over the items being conveyed.

2. Wheel Conveyor

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The wheel conveyor is used in the blasting and side extrusion coating lines. The pipe will move

forward while it is rotating (helix movement).The wheel angle adjustment is activated by means

of spindle jacks, powered by an electric motor. The helix adjustment is fitted to accomplish anadjustable rotation versus linear movement of the pipe.A frequency control system in sections is

provided to obtain a variable pipe production speed and to catch-up and brake-away the pipes at

the incoming and outgoing parts of the conveyor, by increasing the conveyor speed of therelevant section.In order to set the width of the pipe for a specific pipe diameter, the conveyor isfitted with a 'width-adjustment' system.

3. Roller Conveyor

Heavy Duty roller conveyors are used for moving items that are at least 500 lbs. This type of

conveyor makes the handling of such heavy equipment/products easier and more time effective.

Many of the heavy duty roller conveyors can move as fast as 75 feet/minute. Other types of

heavy duty roller conveyors are gravity roller conveyor, chain driven live roller conveyor, palletaccumulation conveyor, multi-strand chain conveyor, and chain & roller transfers. Gravity roller

conveyors are extremely easy to use and are used in many different types of industries such as

automotive and retail. Chain driven live roller conveyors are used for single or bi-directional

material handling. Large heavy loads are moved by chain driven live roller conveyors. Palletaccumulation conveyors are powered through a mechanical clutch. This is used instead of

individually powered and controlled sections of conveyors. Multi-strand chain conveyors are

used for double pitch roller chains. Products that cannot be moved on traditional roller conveyorscan be moved by a multi-strand chain conveyor. Chain & roller conveyors are short runs of two

or more strands of double pitch chain conveyor built into a chain driven line roller conveyor.

These pop up under the load and move the load offof the conveyor.

3(a) Gravity Roller Conveyor

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Also known as Un-powered Roller Conveyor, this is the most common material handling

equipment installed in package handling plants. Plain Rollers with antifriction bearings and

closely spaced are used to the movement of boxes and similar packaged Product in horizontal ordownward path profile. The conveying path is flexible and includes horizontal curves where split

or taper rollers provide a uniform motion for the package. Assembly line operation is specially

suitable for these modules as the Operator has a flexible time available to complete his activityand manually move the sub assembly to the next position. Gravity modules used in conjunctionwith lift stations offer a simple solution to low density work stations.

3(b) Live (Powered) Roller Conveyor

The movement of Pallets, Boxes and similar packaged Product in plant requires the use ofpowered conveyors, and Roller conveyors meet many applications economically. For light duty

requirement, standard rollers are fitted with Sprockets welded to the diameter directly.

Transmission is by Roller to Roller chain loop preferably or by a continuous rack chain drive.For higher torque application and for reversing function, the roller to roller transmission system

is used with outboard sprockets and live shaft rollers. Roller diameter and shell thickness aredecided based on the Package weight and surface condition apart from capacity and duty cycle.

4. Slat Conveyor

Slat conveyors consist of endless chains, driven by electric motors operating through reduction

gears and sprockets, with attached spaced slats to carry objects that would damage a belt becauseof sharp edges or heavy weights.

5. Flat Belt Conveyor

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A conveyor belt (or belt conveyor) consists of two or morepulleys,with a continuous loop of

material - the conveyor belt - that rotates about them. One or both of the pulleys are powered,

moving the belt and the material on the belt forward. The powered pulley is called the drivepulley while the unpowered pulley is called the idler. There are two main industrial classes of

belt conveyors; Those in generalmaterial handling such as those moving boxes along inside a

factory andbulk material handling such as those used to transport industrial and agriculturalmaterials, such as grain, coal, ores, fines and lumps material.

6. Magnetic Belt Conveyor

Magnetic Belt ConveyorsareSteel Conveyor Belts where either a magnetic slider bed ormagnetic pulley is used to transport ferrous materials vertically, upside down, and around

corners .Holds ferrous parts fast to the belt. Holding parts to the belt for elevation changes or

controlled positioning can also be achieved by the use of a magnetic conveyor belt that utilisesmagnets under the moving belt. Magnetic belt conveyors are created by placing permanent

ceramic magnets in the bed of a standard conveyor. Strength and size of magnetic field is

designed per application. Magnetic belt conveyors are one of the surest ways to controlpositioning of ferrous parts for further processing .

7.Troughed Belt Conveyor

Troughed belt conveyors offer an efficient means of transporting materials in large quantities(bulk), over distances ranging from a few meters to several kilometers, continuously.As will be

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seen below, troughed belt conveyors are only one of the types of belt conveyors available in the

market today however, the troughed belt conveyor takes numerous forms and is used in many

different applications with tremendous success. It is important to draw a distinction between bulkhandling of materials and unit handling. The former refers to the transportation of particulate

product(s) on a continuous basis for example, the conveying of lumpy ore from a mine to a

processing plant or for transporting coal from a stockyard to a bunker above a crusher.

8. Bucket Conveyor

Bucket conveyors consist of endless chains or belts to which are attached buckets to convey bulk

material in horizontal, inclined, and vertical paths. The buckets remain in carrying position untilthey are tipped to discharge the material. Various discharging mechanisms are available.

9. Vibrating Conveyor

A Vibrating Conveyor is a machine with a solid conveying surface which is turned up on the sideto form a trough. They are used extensively in food grade applications where sanitation, wash

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down, and low maintenance are essential. Vibrating conveyors are also suitable for harsh, very

hot, dirty, or corrosive environments. They can be used to convey newly cast metal parts which

may reach upwards of 1,500 F (820 C). Due to the fixed nature of the conveying pans vibratingconveyors can also perform tasks such as sorting, screening, classifying and orienting parts.

Vibrating conveyors have been built to convey material at angles exceeding 45 from horizontal

using special pan shapes. Flat pans will convey most materials at a 5 Incline from horizontalline.

10. Screw Conveyor

A screw conveyor or auger conveyor is a mechanism that uses a rotating helicalscrewblade,called a "flighting", usually within a tube, to move liquid or granular materials. They are used in

many bulk handling industries. Screw conveyors in modern industry are often used horizontally

or at a slight incline as an efficient way to move semi-solid materials, including food waste,wood chips, aggregates,cereal grains, animal feed, boiler ash, meat and bone meal,municipal

solid waste,and many others. The first type of screw conveyor was theArchimedes' screw,usedsince ancient times to pump irrigation water. They usually consist of a trough or tube containing

either a spiral blade coiled around a shaft, driven at one end and held at the other, or a "shaftlessspiral", driven at one end and free at the other. The rate of volume transfer is proportional to the

rotation rate of the shaft. In industrial control applications the device is often used as avariable

rate feederby varying the rotation rate of the shaft to deliver a measured rate or quantity of

material into a process. Screw conveyors can be operated with the flow of material inclinedupward. When space allows, this is a very economical method of elevating and conveying. As

the angle of inclination increases, the capacity of a given unit rapidly decreases.

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11. Pneumatic Conveyor

Every pneumatic system, would makes use of pipes or ducts called transportation lines that carry

mixture of materials and a stream of air. These materials are such as dry pulverized or freeflowing or light powdery materials like cement,fly ash etc. These materials can be transported

conveniently to various destinations by means of a stream of high velocity air through pipe lines.

Products are moved through various tubes viaair pressure,allowing for extra vertical versatility.

Pneumatic conveyors are either carrier systems or dilute-phase systems; carrier systems simplypush items from one entry point to one exit point, such as the money-exchanging tubes used at a

bankdrive-through window. Dilute-phase systems use push-pull pressure to guide materialsthrough various entry and/or exit points. It is important to note that either air compressors,

vacuums, or blowers can be used to generate the air. This will all depend on what the engineersthink will be the most efficient and economical way of developing the system.

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14. Tow Conveyor

Tow conveyors may be overhead trolley cars or floor conveyors adapted for handling dollies,trucks, and cars, which are locked into the towing chain to be moved from any point in the

system to any other point.

15. Trolley Conveyor

In trolley conveyors an overhead rail carries a series of load-bearing containers (trolleys) that

are coupled together on an endless propelling medium such as cable, chain, or other linkage. The

trolleys may be hooks, magnets, or various carriers designed for the particular load to be

handled. The rails are usually supported by the framework of the plant building.

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16. Power-and-Free Conveyor

For enclosed track Power and Free conveying, the S-310 is one of the most versatile power and

free conveyors in the industry due to its compact design and ability to carry loads in slot down

or slot up (inverted Power and Free) orientations.

17. Monorail

A monorail is arail-based transportation system railway in which the track consists of a singlerail, typically elevated and with the trains suspended from it. The term is also used variously to

describe the beam of the system, or the vehicles traveling on such a beam or track. The term

originates from joiningmono (one) and rail (rail), from as early as 1897, possibly from German

engineerEugen Langen who called an elevated railway system with wagons suspendedtheEugen Langen One-railed Suspension Tramway (Einschieniges Hngebahnsystem Eugen

Langen). The transportation system is often referred to as a railway

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VIBRATORY CONVEYORS

Vibrating Conveyors innately brings many benefits that were not previously available. This

includes Energy Efficiency, added operating versatility and more which are inherent with thiskind of Vibratory Drive. Repeated starts with full loads are tolerated. So are other types ofabusive loading. Installation under the outlet of a Bin or Silo or being supplied by loader dumps

or other large batch loads, such as those from casting cleaners in a Foundry, are permissible. Of

course, for these applications the Conveyors trough has needed structural integrity, but this kindof loading is not detrimental to the Vibratory Drive.

The electrically adjustable conveying speed is beneficial for picking, inspecting, cleaning or

similar purposes while being conveyed. So is the automatic, repetitive pulsing to a morevigorous vibratory action when sticky (adhesive) bulk solids are being transported. The reduced

cost of Dynamic Counterbalancing and its stability when the Conveyor changes from no load to

full load easily overcomes the alternative choice of a non-balanced design. The price savingsappears to be meager when the increased installation cost and the realistic risk of the

transmission of nuisance vibration to the surrounding area are taken into account.

Conveyors of long lengths are now practical. Particularly when heavy loads are being carried.

The reason is the needed motors are appropriately spread all along the length. The multi-motor

combination automatically synchronizes to develop the total amount of power required. Thismotor distribution also minimizes the dynamic stresses which helps to make very long Vibrating

Conveyors possible. Sanitary, food grade, extra heavy duty, low profile, dynamically

counterbalanced and non-balanced design Vibrating Conveyors are available with virtually all

types of trough construction. Carbon steel, stainless steel and fiberglass are just a few of the

fabrication materials available.

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PREFERABLE FEATURES OF VTC

Versatile Applications: Vibrating Conveyors are inherently self-cleaning which makes them

desirable for sanitary applications or when material contamination is to be minimized or avoided.

Sanitary polishes that meet FDA standards are available.

Various Drive Configurations:Underside Design: The vibratory drive system is located

underneath the conveying trough. This is the usual location for Driven Conveyors.

Top Drive Design: The vibratory drive system is located above the conveying trough. This

arrangement allows the bottom of the conveying trough to be fully accessible for various

discharge ports.

End Drive Design: The vibratory drive system is located on either end of the Vibrating

Conveyor. This arrangement has the advantage of a low profile type of design which minimizes

head room requirements.

Larger Dimensions: VTC Vibrating Conveyors can be manufactured in larger dimensions.

Since the VTC Drive distributes the input dynamic forces, the diameter or length and widthdimensions are not restricted as they would be if they were concentrated at one point. For this

reason, VTC Driven Vibrating Conveyors are unidirectional and standardized in widths to 18 ft.

and lengths and diameters as required.

Simple Electrical Control: Our innovative technology improves performance. The operating

stroke and frequency on VTC Vibrating Conveyors can be automatically and repetitively

pulsed.

Tolerating Head loads: The repeated starts and stops are not detrimental to the Conveyor.

Reduced Sound Levels: Reduced sound levels are another benefit of VTC VibratingConveyors. Our Conveyors typically operate less than 80 dBA in the loaded condition.

45 Stroke Angle: Instead of being limited to 30, the better conveying angle of 45 can nowbe used when its wanted.

Adjustable Conveying Rate: Inherent with the VTC Drive, the full range of adjustment isavailable. This elevated control is useful for reducing operating noise, heating particles and

cooling unit pieces" such as Foundry castings.

Minimal Maintenance: VTCs Vibrating Conveyors only require the look and listenprinciple of maintenance. Just note the stroke and listen for noise.

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Interchangeable Components: Most of the component parts of the VTC Vibrating Conveyor

are interchangeable with other VTC Driven units even though their functions may differ. These

common components extend to VTCs Vibrating Feeders, Screens, Fluid Bed Coolers andDryers, Spiral Elevators and various types of Foundry units. This reduces the number of spare

parts required in inventory.

CLASSIFICATION OF MATERIAL TO BE CONVEYED

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The typical materials encountered are either Unit Pieces or Bulk Solids.

Unit Pieces: These are whole solids that are a complete entity and are not compressible.

Examples are steel castings, bolts, fasteners, filled bags, metal stampings, briquettes or wooden

logs.

Virtually all Unit Pieces are essentially Free Flowing even if their size and moisture contentmarkedly changes. Therefore, any Induced Vertical Flow is not needed, and they convey very

well with vibration.

Bulk Solids: This kind of material is composed of particles. Even though there are a myriadnumber of different kinds of bulk solids, fortunately they can be classified into three groups to

better understand their handling characteristics. Their common characteristics must be combined

with any potential for Set or consolidation which is also listed.

Flakes: Are flat shaped particles or strands that are usually fibrous that will compress. Wood

bark, shavings or chips are examples. Others are glass fibers, polystyrene film, refuse derived

fuel (RDF), bagasse, shredded rubber tires, metal turnings, brass needles, stranded insulation,shredded tobacco, sander dust, polypropylene flakes, glass fibers, whole green beans, long chili

peppers, tea leaves, bran, peanut shells or the like.

As Flake type particles become larger in size, higher in moisture content or more easy to

compress, they usually increase in difficulty to discharge from storage or to convey with

vibration.

Floodable: These particles are very fine and dry. They easily aerate so they are said to be"Floodable". The name calls attention to their being able to flow uncontrolled unlessprecautionary measures are taken. A particle size smaller than 100 mesh and less than 2%

moisture content more specifically describes this kind of bulk solid. Hydrate lime, fly ash, kaolin

clay, pesticides, virtually all the different dusts from collectors, acetylene black, carbon black,

stucco, bentonite, talcum powder, diatomaceous earth, cement, ink dyes, powdered milk,

dextrose, powdered sugar or anything similar exemplify bulk solids that are floodable.

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As a "Floodable" bulk solid becomes more fine and dry, it is much more difficult to discharge

from storage or to convey with vibtation.

Generally Granular: These bulk solids are those that do not qualify as being either Flake or

Floodable. The particles are typically granular in texture and often have firm and hard lumps intheir size distribution. Coal, limestone, gypsum, sawdust, bottom ash, rice, grits, salt, bone meal,

corn gluten, soybean meal, granulated sugar, fertilizer beads such as urea, molding sands andpotash denote the generally granular classification of bulk solids.

If Generally Granular bulk solids increase in the amount of fines and moisture content, theybecome more difficult to discharge from storage or to convey with vibration. (When the

particles are near 100% fine content and saturated with water, they become a slurry.)

CONTENDING WITH SET OR CONSOLIDATION

Any degree of Set or Consolidation of any of these bulk solids should be noted. This is the

fusion or the sticking together of the solidified, stored particles when they spend time in dormantstorage. After about 12 hours, Set begins to solidify the stored particles. This bondingnormally increases over the next 24 to 48 hours and the solidification becomes formidable. After

that time it still solidifies but at a slower rate. Examples would be the waste type coals, such as

silt, culm and gob, sodium chlorate, fly ash, spent grain or freshly ground soybean meal. Also,many Generally Granular particles that have a high degree of fines will also have a high degree

of Set. Another would be particles that are hot when placed in storage and agglomerate as they

cool such as storing freshly ground soybean meal.

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INDUCED VERTICAL FLOW

DISCHARGING

The benefit of Induced Vertical Flow is it can be applied when Impelled Retrieving cannot

be justified and the bulk solid to be stored is beyond the practical limits of Static Design

technology.

The generated vibratory action markedly reduces any stored materials inter-particle friction,combined particle shear strength and wall friction. Very high vibratory forces can shatter set

and unlock interwoven and interlocked flake type particles. Therefore, the stored material

vertically flows from the storage means, such as a Container, Bin, Silo, Storage Pile or Rail Car,in conjunction with the force of gravity. Since these machines need to be operated in a manner

that agrees with the stored materials natural vertical flow pattern, they sho uld not have any

other function such as feeding. This permits them to be cycle type operated whenever it is

required to do so.

Bin Activators, Activated Bins, Container Activators (which includes resilient bags), StoragePile Dischargers and Rail Car Dischargers make up this group of machines.

DENSIFYING

Virtually all the "Flake" type of bulk solids (like wood chips) can be Densified to increase their

loaded weight by 15 to 30 percent.

"Floodable" powder like particles (such as flour) can be increased in loaded weight by 20 to 35

percent."Generally Granular" particles and lumps that have a density of less than 50 PCF (such

as bran) will readily increase in loaded weight by 15 to 30 percent. For density of more than 50

PCF, the increase will probably be 12 to 20 percent.

Vibrating Tables, Vertical Faces and Rail Car Densifiers are available for this purpose.

INDUCED CONVEYING

A benefit of Induced Conveying is the vibratory stroke can shatter fused Set when started

up. Also, sticky (adhesive) materials can be conveyed by combining the use of an appropriate

trough liner, supplementing the needed conveying action with an automatic, repetitive pulsingthat has a momentary more vigorous vibratory action and conveying it as slowly as practical with

a much more deep mat depth to achieve the needed TPH required.

The Induced Conveying kind of vibratory machines include Vibrating Feeders, Conveyors,

Screens, Fluidized Bed Heat Transferring and the like.

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VIBRATORY TUBE CONVEYOR

Vibratory motion conveyor is used to transport sand material from one point to another in a

horizontal plane. The equipment consists of a long hollow tube which is mounted on a set ofsprings inclined 65 degree to horizontal. A belt drive-pulley mechanism transmits power from

an electrical motor to a shaft which is attached to a cam, which provides an eccentric motion to

the tube. Cam and tube are connected in the middle. This eccentric motion of the cam is

translated into a vibratory motion.

Eccentric

In mechanical engineering, an eccentric is a circular disk (eccentric sheave) solidly fixed to a

rotating axle with its centre offset from that of the axle (hence the word "eccentric", out of thecentre).It is most often employed in steam engines and used to convert rotary into linear

reciprocating motion in order to drive a sliding valve or a pump ram. In order to do so an

eccentric usually has a groove at its circumference around which is closely fitted a circular collar(eccentric strap) attached to which an eccentric rod is suspended in such a way that its other end

can impart the required reciprocating motion. A return crank fulfils the same function except that

it can only work at the end of an axle or on the outside of a wheel whereas an eccentric can alsobe fitted to the body of the axle between the wheels. Unlike a cam, which also converts rotary

into linear motion at almost any rate of acceleration and deceleration, an eccentric or return crank

can only impart simple harmonic motion.

DC Motor

A DC motor relies on the fact that like magnet poles repels and unlike magnetic poles attracts

each other. A coil of wire with a current running through it generates a electromagnetic field

aligned with the center of the coil. By switching the current on or off in a coil its magnet fieldcan be switched on or off or by switching the direction of the current in the coil the direction of

the generated magnetic field can be switched 180. A simple DC motor typically has a stationary

set of magnets in the stator and an armature with a series of two or more windings of wirewrapped in insulated stack slots around iron pole pieces (called stack teeth) with the ends of the

wires terminating on a commutator. The armature includes the mounting bearings that keep it in

the center of the motor and the power shaft of the motor and the commutator connections. The

winding in the armature continues to loop all the way around the armature and uses either singleor parallel conductors (wires), and can circle several times around the stack teeth. The total

amount of current sent to the coil and the coils size and what it wrapped around dictates the

strength of the electromagnetic field created. The sequence of turning a particular coil on or offdictates what direction the effective electromagnetic fields are pointed. By turning on and off

coils in sequence a rotating magnetic field can be created. These rotating magnetic fields interact

with the magnetic fields of the magnets (permanent or electromagnets) in the stationary part of

the motor (stator) to create a force on the armature which causes it to rotate. In some DC motor

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designs the stator fields use electromagnets to create their magnetic fields which allow greater

control over the motor. At high power levels, DC motors are almost always cooled using forced

air.

Helical spring

A coil spring, also known as a helical spring, is a mechanical device, which is typically used to

store energy due to resilience and subsequently release it, to absorb shock, or to maintain a forcebetween contacting surfaces. They are made of an elastic material formed into the shape of a

helix which returns to its natural length when unloaded.

One type of coil spring is a torsion spring: the material of the spring acts in torsion when the

spring is compressed or extended. The quality of spring is judged from the energy it can absorb.

the spring which is capable of absorbing the greatest amount of energy for the given stress is thebest one. Metal coil springs are made by winding a wire around a shaped former - a cylinder is

used to form cylindrical coil springs.

Monazite

Monazite is a reddish-brownphosphate mineral containingrare earth metals. It occurs usually in

small isolatedcrystals.There are at least four different kinds of monazite, depending on relative

elemental composition of the mineral:

monazite-Ce (Ce, La, Pr, Nd, Th, Y)PO4

monazite-La (La, Ce, Nd, Pr)PO4

monazite-Nd (Nd, La, Ce, Pr)PO4

monazite-Sm (Sm, Gd, Ce, Th)PO4

The elements in parentheses are listed in the order in which they are in relative proportion within

the mineral, so that lanthanum is the most common rare earth in monazite-La, and soforth.Silica, SiO2, will be present in trace amounts, as well as small amounts

ofuranium andthorium. Due to thealpha decay of thorium and uranium, monazite contains a

significant amount ofhelium,which can be extracted by heating.[2]

Monazite is an importantore for thorium, lanthanum, and cerium. It is often found inplacer

deposits.The deposits inIndia are particularly rich in monazite. It has ahardness of 5.0 to 5.5

and is relativelydense,about 4.6 to 5.7 g/cm3.

Because of the presence of thorium within monazite, it can beradioactive.If samples are kept,they should be placed away fromminerals that can be damaged by radiation. Because of its

radioactive nature, the monazite withinrocks is a useful tool for dating geological events, such as

heating or deformation of the rock.

The name monazite comes from the Greek (to be solitary), in allusion to its isolated

crystals.India,Madagascar,andSouth Africa have large deposits of monazite sands.

http://en.wikipedia.org/wiki/Phosphate_mineralhttp://en.wikipedia.org/wiki/Rare_earth_elementhttp://en.wikipedia.org/wiki/Crystalhttp://en.wikipedia.org/wiki/Ceriumhttp://en.wikipedia.org/wiki/Lanthanumhttp://en.wikipedia.org/wiki/Neodymiumhttp://en.wikipedia.org/wiki/Samariumhttp://en.wikipedia.org/wiki/Silicahttp://en.wikipedia.org/wiki/Uraniumhttp://en.wikipedia.org/wiki/Thoriumhttp://en.wikipedia.org/wiki/Alpha_decayhttp://en.wikipedia.org/wiki/Heliumhttp://en.wikipedia.org/wiki/Monazite#cite_note-2http://en.wikipedia.org/wiki/Orehttp://en.wikipedia.org/wiki/Placer_deposithttp://en.wikipedia.org/wiki/Placer_deposithttp://en.wikipedia.org/wiki/Indiahttp://en.wikipedia.org/wiki/Mohs_scale_of_mineral_hardnesshttp://en.wikipedia.org/wiki/Densityhttp://en.wikipedia.org/wiki/Radioactivehttp://en.wikipedia.org/wiki/Mineralhttp://en.wikipedia.org/wiki/Rockshttp://en.wikipedia.org/wiki/Indiahttp://en.wikipedia.org/wiki/Madagascarhttp://en.wikipedia.org/wiki/South_Africahttp://en.wikipedia.org/wiki/South_Africahttp://en.wikipedia.org/wiki/Madagascarhttp://en.wikipedia.org/wiki/Indiahttp://en.wikipedia.org/wiki/Rockshttp://en.wikipedia.org/wiki/Mineralhttp://en.wikipedia.org/wiki/Radioactivehttp://en.wikipedia.org/wiki/Densityhttp://en.wikipedia.org/wiki/Mohs_scale_of_mineral_hardnesshttp://en.wikipedia.org/wiki/Indiahttp://en.wikipedia.org/wiki/Placer_deposithttp://en.wikipedia.org/wiki/Placer_deposithttp://en.wikipedia.org/wiki/Orehttp://en.wikipedia.org/wiki/Monazite#cite_note-2http://en.wikipedia.org/wiki/Heliumhttp://en.wikipedia.org/wiki/Alpha_decayhttp://en.wikipedia.org/wiki/Thoriumhttp://en.wikipedia.org/wiki/Uraniumhttp://en.wikipedia.org/wiki/Silicahttp://en.wikipedia.org/wiki/Samariumhttp://en.wikipedia.org/wiki/Neodymiumhttp://en.wikipedia.org/wiki/Lanthanumhttp://en.wikipedia.org/wiki/Ceriumhttp://en.wikipedia.org/wiki/Crystalhttp://en.wikipedia.org/wiki/Rare_earth_elementhttp://en.wikipedia.org/wiki/Phosphate_mineral

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Galvanizing

Galvanizing is a process of coating iron or steel with zinc in order to provide greater protection

against corrosion for the iron or steel base. The process of galvanizing sheet iron was developed

simultaneously in France and England in 1837. Both of these methods employed a "hot dipping"

process to coat sheet iron with zinc. Like tinplate, early galvanized metals were hand dipped.

Today almost all galvanized iron and steel is electroplated.