Transportation: Construction Equipments

TRANSPORTATIONCONSTRUCTION EQUIPMENTS

TRANSPORTATION

Transport or transportation is the movement of people, animals and goods from one location to another. 

Modes of transport include air, rail, road, water, cable, pipeline and space. The field can be divided into infrastructure, vehicles and operations.

Transport is important since it enables trade between people, which in turn establishes civilizations.

Transport infrastructure consists of the fixed installations necessary for transport, including roads, railways, airways, waterways, canals and pipelines and terminals such as airports, railway stations, bus stations, etc.

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TRANSPORTATION

A truck is a motor vehicle for transporting goods.

Unlike automobiles, which usually have a unibody construction, most trucks (with the exception of the car-like minivan) are built around a strong frame called a chassis.

They come in all sizes, from the automobile-sized pickup truck to towering off-road mining trucks or heavy highway semi-trailers.

TRUCK

A truck (US, CA and AU) or lorry (UK and Ireland) is a motor vehicle designed to transport goods.

Hauling is the activity of transporting goods by truck. The trucks are hauling units that provide relatively low hauling cost because of their high travel speeds.

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LIGHT TRUCKS

MEDIUM TRUCKS VERY HEAVY TRUCKS

HEAVY TRUCKS

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A dump truck  is a truck used for transporting loose material (such as sand, gravel or dirt) for construction.

Typical dump truck is equipped with a hydraulically operated open-box bed hinged at the rear.

WHAT ARE DUMPERS…??

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TYPES OF DUMPERS Standard dump truck

Side dump truck

Off- road dump truck

Articulated dump truck

Transfer dump truck

Super dump truck

Semi trailer dump truck

Double trailer bottom truck

A standard dump truck is a full truck chassis with a dump body mounted to the frame.

The dump body is raised by a hydraulic ramp mounted forward of the front bulkhead, between the truck cab and the dump body.

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STANDARD DUMP TRUCK

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A side dump truck consists of a 3 – axle tractor pulling a 2 – axle semi trailer .

It has hydraulic rams which tilt the dump body onto its side , spilling the material to either the left or right side of the trailer.

The key advantages of the side dump are that it allows rapid unloading and can carry more weight.

SIDE DUMP TRUCK

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Off – road dump trucks more closely resemble heavy construction equipment or engineering vehicles.

They are used strictly off – road for mining and heavy dirt hauling jobs. The term ‘dump’ truck is not generally used by the mining industry.

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An articulated dump truck has a hinge between the cab and the dump box, but is distinct from semi trailer trucks in the cab is a permanent fixture , not a severable vehicle. This vehicle is highly adaptable to rough terrain.

A transfer dump truck is a standard dump truck which pulls a separate trailer which can be loaded with aggregate (gravel, sand, asphalt, etc.)

ARTICULATED DUMP TRUCK

TRANSFER DUMP TRUCK

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SEMI TRAILER BOTTOM DUMP TRUCK

A semi bottom dump (or "belly dump") is a 3-axle tractor pulling a 2-axle trailer with a clam shell type dump gate in the belly of the trailer.

The key advantage of a semi bottom dump is its ability to lay material in a wind row (a linear heap).

SUPER DUMP TRUCK:

A super dump is similar to a standard dump truck except it is equipped with extra axles to carry more weight .

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DOUBLE AND TRIPLE TRAILOR BOTTOM DUMP TRUCK

Double and triple bottom dumps consist of a 2-axle tractor pulling one single-axle semi-trailer and an additional full trailer.

These dump trucks allow the driver to lay material in wind rows without ever leaving the cab or even stopping the truck.

The main disadvantage is the difficulty in backing double and triple units in reverse.

•Transporting material from one place to another over a stationary structure.

•Caries material in continuous stream with its distinct feature such as endless chain or belt.

•Can be done horizontally, vertically or inclined.

•When the equipment does horizontal conveying, it is known as conveyor and when it does vertical, it is known as elevator.

•Conveying are mainly used in mining, construction and in some of the industries.

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CONVEYING EQUIPMENTS

Conveyors are a piece of plant moving mainly in the horizontal direction.

Conveyors are used mainly for transporting aggregates and concrete and generally considered only in large sites where there may be a large concrete mixing complex.

These are the equipment to move material over a fixed path between specific points.

These are used in mining , heavy & light industry , food & beverage processing , agriculture , construction projects.

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CONVEYORS

BELT CONVEYORS:

•Used when large quantities of materials have to be conveyed over long distances at fast speed.•It consists of a belt running over a pair of end drums or pulleys and supported at regular intervals by a series of rollers called idlers.•These idlers are supported on a conveyor frame.•The middle sag provided in the belt prevent the spilling of material.•Generally, rubber is most commonly used as conveyor belt.

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ADVANTAGES OF BELT CONVEYOR

• It can handle light as well as heavy materials, dry or wet, fine or coarse etc.

• It can and for distances to convey several thousand tons of material per hour and for distances of distances of several kilometers.

• It can carry material horizontally or inclined.

• It is lighter in weight then other conveyors.

• It gives controlled discharge of material and discharge can be controlled by the speed of the belt.

There are two types of belt conveyor:

1. Horizontal belt conveyor 2. Inclined belt conveyor

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HORIZONTAL BELT CONVEYOR

•The conveyor belt system consists of a continuous moving belt that carries materials or packages from one place to another. •In this system the conveyor belt moves in horizontal direction.

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INCLINED BELT CONVEYOR

•It is designed for steep excavation work, it is ideal for basement excavating, utility contracting and other earth and material applications.•The belt buckets have a high capacity to eliminate material rollback at steep inclines.

IN CASE OF INCLINED BELT CONVEYOR

•It can move gravel, mud, dirt, silt etc.•From 0º to 70º•It is used for digging basements, general excavation and construction.• It fits in small window openings, manhole covers, etc.

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SCREW CONVEYOR

•Screw conveyors are of simple, relatively low cost construction compared to other conveyor systems. •Screw conveying systems consist of a helical flight fastened around a pipe or solid shaft, mounted within a tubular or U-shaped trough•It permits intermediate discharge of the material at several points.• It is a bulk material handling unit.• It is suitable for the conveying of granular or powder material and liquids. •It can perform horizontal, inclined(as an efficient way to move semi-solid materials) and vertical conveying. • The angle of inclination of inclined conveyors is usually 10° to 20°. •The conveying length is 2 meters to 70 meters. Screw dia. 100 to 900 mm.

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Uses-

•They are used for handling of dry & semi liquid material for Mixing and Blending of material. • Used in grain & oil, feed, food, metallurgy, mine, plastic, chemical engineering, building material, medicine industries.• Used for extraction, filling and transporting raw material like cement, concrete, sludge and various aggregates.•to transfer crushed materials from one place to another.

Some of the many advantages of a screw conveyor are:

•Economical•Low maintenance•Totally enclosed•Multiple discharge locations•Easy to install•Quiet operation•Can operate on inclines

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BUCKET ELEVATOR

•Bucket elevators are designed to move flowing powders or bulk solids. •Bucket elevators use an endless belt or chain and have a series of •buckets attached to it. •Bulk material is spread into an inlet hopper. •Buckets (or cups) dig into the material and convey it up and over• the head sprocket/pulley, and then throw the material •out a discharge throat.•The plastic buckets are truly interlocking and never separate. •This equipment is mainly used for the lift conveying of •the materials at the lower position to the upper specified position.

There are three types of bucket elevator:

1. Continuous discharge bucket elevator2. Centrifugal discharge bucket elevator 3. Positive discharge bucket elevator

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• Buckets are mounted without any gap on a chain or

belt. This type of elevator often used for handling larger lumps of material that may be difficult to convey by centrifugal type.

• It is also called Low-Speed Gravity Discharge Elevators and speed range of 30 to 50 m/min.

• This type of elevator suitable for fragile, fluffy or pulverised materials.

• It can operate in the vertical or inclined condition.

Application:1. Lime, 2. Cement and3. Dry chemicals

CONTINUOUS BUCKET ELEVATOR

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ADVANTAGES

•It is ideal for transporting in factories without damaging or breaking the product.

• The gentlest possible handling of product with the least spillage, lowest possible maintenance, and the quietest operation.

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CENTRIFUGAL BUCKET ELEVATORS

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Applications:Grain, Coal, Sand, Clay, Sugar and Dry Chemicals.

•Centrifugal discharge for small grain.•They operate at high speeds, which throw the materials out the buckets into discharge throats by centrifugal force.•In a centrifugal discharge elevator, buckets are fixed on to belt or chain at regular pitch to avoid interference in loading and discharge. •This type of elevators is mostly vertical in operation and can handle practically any free flowing fine or small lumpy materials.•Speed range is 70 to 125 m/min.•Usually lump size larger than 50mm are not used for these types of elevators. On the other hand, it is also necessary to check that the materials are not finer than 200 mesh size.

•This type of elevators is similar to the centrifugal discharge elevator except for two distinguishing features.

•The buckets are spaced at regular pitch and mounted on two strands of chains, and are provided with a snub wheel under the head sprockets to ensure inverting of the bucket for complete discharge.

•The speed of the bucket is slow in the range of 35 – 40 m/min.

•This type of elevators is used for handling light, fluffy, dusty and sticky materials. The feeding is done by the scooping or digging by the buckets.

POSITIVE DISCHARGE ELEVATORS

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CONSTRUCTION ELEVATOR

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•Also known as a construction hoist, temporary elevator. •This type of elevator is commonly used for large scale construction projects.•It is used to carry materials, and equipment quickly between the ground and higher floors, or between floors in the middle of a structure. •The construction elevator is made up of either one or two cars (cages) which travel vertically along with tower sections.•Modern construction elevators use a motorized rack-and-pinion system that climbs the structured sections at various speeds.

This elevator are widely used at the sites of :-

•Industrial and civil construction, •Bridge construction, •Underground construction, •Large chimney construction, •Ship industry,

EXPLOSION PROOF ELEVATORS

•Explosion proof elevators is used where there is a risk of explosive gases or dusts being present.

•The drive and control units are mounted on top of the car.

•We use a durable, reliable motor that is designed for outdoor use.

•All elevators are equipped with a dual-motor system to build an extra level of reliability and safety into the system.

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•The most common types of industrial elevators are hoist elevators and incline elevators.

•These types of elevators are built to carry huge amounts of weight

•Hoist elevators are operated by a pulley or series of pulleys and they can be a simple platform or a cage in which heavy materials are moved up and down.

This type of elevators is used in :

•Construction, •Warehouses, •And shipyards. 

HOIST ELEVATORS 

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A crane is a type of machine, generally equipped with a hoist, wireropes or chains, and sheaves.

it is used to lift and lower materials and to move them horizontally.

It is mainly used for lifting heavy things and transporting them to other places.

Cranes are commonly employed in the transport industry for the loading and unloading of freight, in the construction industry for the movement of materials and in the manufacturing industry for the assembling of heavy equipment.

CRANE

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OVERHEAD CRANE-

MOBILE CRANEo TRUCK-MOUNTED CRANEo SIDELIFT CRANEo ROUGH TERRAIN CRANEo ALL TERRAIN CRANEo PICK AND CARRY CRANEo CARRY DECK CRANEo TELESCOPIC HANDLER CRANEo CRAWLER CRANEo  RAILROAD CRANEo  FLOATING CRANE

Instead of the whole crane moving, only the hoist / trolley assembly moves in onedirection along one or two fixed beamsOften mounted along the side walls or on elevated columns in the assembly area of factory.

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TYPES OF CRANE

TOWER CRANE(FIXED)o SELF-ERECTING CRANEo TELESCOPIC CRANEo HAMMERHEAD CRANEo  LEVEL LUFFING CRANEo GANTRY CRANEo  DECK CRANEo  JIB CRANEo  BULK-HANDLING CRANEo LOADER CRANEo STACKER CRANE

A MOBILE CRANE IS "A CABLE-CONTROLLED CRANE MOUNTED ON CRAWLERS OR RUBBER-TIRED CARRIERS" OR “ a hydraulic-power crane with a telescoping boom mounted on a truck types carriers or as a self propelled models." They are designed to easily transport to a site and use with different types of load and cargo with little or no setup or assembly.

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MOBILE CRANE

PICK AND CARRY CRANE

CARRY DECK CRANE

A Pick and Carry Crane is similar to a mobile crane in that is designed to travel on public roads.Pick and Carry cranes have no stabilizer legs or outriggers and are designed to lift the load and carry it to its destination, within a small radius, then be able to drive to the next job.

A carry deck crane is a small 4 wheel crane with a 360 degree rotating boom placed right in the centre and an operators cab located at one end under this boom. They Carry deck can hoist a load in a confined space and then load it on the deck space around the cab or engine and subsequently move to another site.

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TELESCOPIC HANDLER CRANE

Telescopic Handlers are like forklift trucks that have a telescoping extendable boom like a crane

These new 360 degree telescopic handler/crane models have outriggers or stabilizer legs that must be lowered before lifting,

These machines are often used to handle pallets of bricks and install frame trusses on many new building sites and they have eroded much of the work for small telescopic truck cranes.

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TRUCK MOUNTED CRANE

ROUGH TERRAIN CRANE

A crane mounted on a truck carrier provides the mobility for this type of crane.

Outriggers are extended horizontally and vertically to level and stabilize the crane while stationary and hoisting.

A crane mounted on an undercarriage with four rubber tires that is designed for pick-and-carry operations and for off-road and “rough terrain” applications.Outriggers are used to level and stabilize the crane for hoisting.

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ALL TERRAIN CRANE

CRAWLER CRANE

A set of tracks called crawler that provides stability and mobility.

A mobile crane with the necessary equipment to travel at speed on public roads, and on rough terrain at the job site using all-wheel and crab steering.Lifting loads up to 1200 metric tons.

They can move around on site and perform each lift with little setup,since

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RAIL ROAD CRANE

FLOATING CRANE

A railroad crane has flanged wheels for use on railroads.

The simplest form is a crane mounted on a railroad car.

Floating cranes are used mainly in bridge building and port construction.They are also used for occasional loading and unloading of especially heavy or awkward loads on and off ships.

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AREIL CRANE

SIDE LIFTING CRANE

Aerial crane or ‘Sky cranes’ usually are helicopters designed to lift large loads.

Helicopters are able to travel to andlift in areas that are difficult to reach by conventional cranes.

A side lifter crane is a road-going truck or semi-trailer, able to hoist and transport ISO standard containers.Container lift is done with parallel crane-like hoists, which can lift acontainer from the ground or from a railway vehicle.

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TOWER CRANE Fixed to the ground on a concrete slab.

The base is then attached to the mast which gives the crane its height. Further the mast is attached to the slewing unit (gear and motor) that allows the crane to rotate.

On top of the slewing unit there are three main parts which are: the long horizontal jib (working arm), shorter counter-jib, and the operator's cab.

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SELF ERECTING CRANE

TELESCOPIC CRANE

Also called self-assembling or “Kangaroo” cranes.

lift themselves off the ground using jacks, allowing the next section of the tower to be inserted at ground level or lifted into placeby the partially erected crane itself.

A telescopic crane has a boom that consists of a number of tubes fitted one inside the other.A hydraulic or other powered mechanism extends or retracts the tubes to increase or decrease the total length of the boom. Use in rescue jobs, lifting boats in and out of the water,

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HAMMERHEAD CRANE

LEVEL LUFFING CRANE

The “hammerhead”, or giant cantilever, crane is a fixed-jib crane consisting of a steel-braced tower on which revolves a large, horizontal, double cantilever.the forward part of this cantilever or jib carries the lifting trolley, the jib is extended backwards in order to form a support for the machinery and counter balancing weight.

Normally a crane with a hinged jib will tend to have its hook also move up anddown as the jib moves (or luffs).A level luffing crane is a crane of this common design, but with an extra mechanism to keep the hook level when luffing.

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GANTRY CRANE

DECK CRANE

Located on the ships and boats, these are used for cargo operations or boat unloading and retrieval where no shore unloading facilities are available.Most are diesel-hydraulic or electric-hydraulic.

The crane frame is supported on a gantrysystem with equalized beams and wheels that run on the gantry rail, usually perpendicular to the trolley travel direction. Hoist in a fixed machinery house or on a trolley that runs horizontally along rails, usually fitted on a single beam (mono-girder) or two beams.

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JIB CRANE

BULK HANDLING CRANE

A jib crane is a type of crane where a horizontal member (jib or boom), supporting a moveable hoist, is fixed to a wall or to a floor-mounted pillar.Jib cranes are used in industrialpremises and on military vehicles.

Bulk-handling cranes are designed from the outset to carry a shell grab or bucket, rather than using a hook and a sling.

They are used for bulk cargoes,such as coal, minerals, scrap metal etc.

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LOADER CRANE

STACKER CRANE

The crane moves on a track in an aisle of the warehouse.

It is used for loading/unloadingthe vehicle.

It is a hydraulically-powered articulated arm fitted to a truck or trailer.

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A crane with a forklift type mechanism used in automated(computer controlled) warehouses.

HOIST

A hoist is a device used for lifting or lowering a load by means of a drum or lift-wheel around which rope or chain wraps. It may be manually operated, electrically or pneumatically driven and may use chain, fiber or wire rope as its lifting medium. The load is attached to the hoist by means of a lifting hook.

TYPES OF HOIST-Wire Rope Hoist or Chain Hoist

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Construction hoists Mine hoists

CONCRETE

Concrete is a composite construction material .

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There are two methods of mixing concrete :-There are two method of mixing of concrete:1. Hand mixing2. Machine mixing

HAND MIXING :- it is the method in which we prepare a concrete by hand with the help of tools . It requires a lot of labor and time .The process of mixing is completed in 6-8 mins of adding water. This method of mixing is not good but for small work it is commonly adopted .

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CONCRETE MIXER

The concrete mixer was invented by columbus industria.

A concrete mixer is a device that homogeneously combines cement , aggregates such as sand , gravel stone and water to form .

THE CONCRETE MIXER PROCESS:-

•Concrete mixers come in many shapes and sizes .

•However , almost all mixers consist of a revolving drum that rotates at an even speed .

•The concrete materials are placed into this drum , along with water .

•As the drum rotates the materials become mixed together .

•Over the time , the concrete becomes thoroughly mixed , offering a mixture that delivers a maximum uniformity .

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MACHINE MIXING

•In large and important work concrete mixing is preferred .•Required quantities if sand and coarse aggregates are placed in the drum of the mixer. •4 to 5 rotations are made for dry mixing and then required quantity of cement is added and dry mixing is made with another 4 to 5 rotations. •Water is gradually added and drum is rotated for 2 to 3 minutes during which period it makes about 50 rotations.• At this stage uniform and homogeneous mix is obtained.

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ADVANTAGES OF CONCRETE MIXER:-

•Concrete is always fresh .•It can also save lots of time, labor and money.•Concrete is blended homogenously , creating a much better result than mixing manually.•There is not a chance of wastage of material.•Faster production of concrete at the site .•Improve concrete quality control and consistency.

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TYPES OF CONCRETE MIXERS:

Self-loading truck concrete mixers,Drum roller concrete mixer Volumetric concrete mixersMobile volumetric batching plantsReversing drum mixerPan mixer

SELF – LOADING TRUCK CONCRETE MIXER :-

•Self-Loading Concrete Truck Mixer is fitted with electronic weight batching equipment which shows the exact weight of raw materials going into the drum and the exact amount of concrete that is discharged. •This allows the operator to split loads of any quantity and enables multiple deliveries. A further advantage is that it can re-load with raw materials from any builders merchants or satellite depot, as it has its own batching equipment, self-loading equipment, on-board water system and auxiliary engine. • It can be fitted to any cab/chassis, with the correct specifications, or even onto a trailer.

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Volumetric Concrete Mixers offer substantial advantages over traditional methods of concrete delivery. •This type of construction equipment is basically a mobile truck mixer and batching plant rolled into one. •All raw materials are stored in separate compartments and these are then metered and mixed into fresh cement where and when it’s needed.• This means that there is no expensive waste of materials, as the unmixed product remains usable indefinitely. •They also eliminate the need for part load charges and problems with over or under-ordering. •Our volumetric trucks can supply all mixes and grades of cement, including screed and mortar.

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DRUM MIXERS

All the drum mixers have a container with a cross section similar . The blades are attached to the inside of the movable drum. Their main purpose is to lift the materials as the drum rotates. In each rotation, the lifted material drops back into the mixer at the bottom of the drum and the cycle starts again. Parameters that can be controlled are the rotation speed of the drum and, in certain mixers, the angle of inclination of the rotation axis. There are three main types of drum mixers:• non-tilting drum;• reversing drum;• tilting drum.

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•The reversing drum is similar to the non-tilting mixer except that the same opening is used to add the constituents and to discharge concrete.• The drum rotates in one direction for mixing and in the opposite direction for discharging the concrete.• There are two types of blades attached to the inner walls of the drum.•One set drags the concrete upwards and toward the center of the mixer when the drum rotates in one direction; the second set of blades pushes the concrete toward the opening when the drum rotates in the other direction.• The blades have a spiral arrangement to obtain the desired effect for discharge and mixing. •Reversing drum mixers are usually used for batches up to 1 m 3 m .

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•The truck mixers belong to the reversing category of drum mixers.

• The driver of the truck can control the speed of rotation with a clutch in the cabin.

•Reversing drum mixer a type of concrete mixer that produces concrete in single batches.

•The entire drum rotates around its axis as materials are loaded through a charge chute at one end of the drum and exit through a discharge chute at the opposite end of the drum.

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PUMPS

•A pump is a device used to move liquids or slurries. •A pump moves liquids from lower pressure to higher pressure, and overcomes this difference in pressure by adding energy to the system.•Pumps work by using mechanical forces to push the material, either by physically lifting, or by the force of compression.•Technically, a pump is a unit used for transportation of liquids, fluids and gases through pipes or similar channels.•The functionality of pumps is very simple, it consists of a suction mechanism at one end where the material is drawn in. Counter pressure is developed at the other end which forces the material out.

PUMPS

piston pumps centrifugal pumpssubmersible pumps jet pumps

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SUBMERSIBLE PUMP

•The whole assembly is submerged in the fluid to be pumped. •The advantage of this type of pump is that it can provide a significant lifting force as it does not rely on external air pressure to lift the fluid.

•The power source is usually an electric motor. •Their compact and streamlined design makes them ideal for wells and other jobs where space is limited.

•These can be used for a depth of 80’ – 100’ depending on the depth of the water table.

Submersible pumps are found in many applications, such as drainage, sewage pumping, general industrial pumping and slurry pumping, for water abstraction or in water wells.

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•A concrete pump is a machine used for transferring

•The first type of concrete pump is attached to a truck.

• It is known as a trailer-mounted boom concrete pump because it uses a remote-controlled articulating robotic arm (called a boom) to place concrete with pinpoint accuracy.

• Boom pumps are used on most of the larger construction projects as they are capable of pumping at very high volumes and because of the labor saving nature of the placing boom.

• They are a revolutionary alternative to truck-mounted concrete pumps.

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•The second main type of concrete pump is either mounted on a truck and known as a truck-mounted concrete pump or placed on a trailer and it is commonly referred to as a line pump or trailer-mounted concrete pump.

• This pump requires steel or flexible concrete placing hoses to be manually attached to the outlet of the machine.

• Those hoses are linked together and lead to wherever the concrete needs to be placed. Line pumps normally pump concrete at lower volumes than boom pumps and are used for smaller volume concrete placing applications such as swimming pools sidewalks and single family home concrete slabs and most ground slabs.

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REQUIREMENTS FOR PUMPED CONCRETE:-

Concrete mixture should neither be too harsh nor too sticky; also, neither too dry nor too wet.

A slump between 50 and 150 mm is recommended (note that pumping induces partial compaction, so the slump at delivery point may be decreased)

If the water content in the mixture is low, the coarse particles would exert pressure on the pipe walls. Friction is minimized at the correct water contents. The presence of a lubricating film of mortar at the walls of the pipe also greatly reduces the friction.

High cement content in concrete is generally beneficial for pumping.

Water is the only pump able component in the concrete, and transmits the pressure on to the other components.

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• Two types of blockage to efficient pumping could occur: (1) Water can escape from the mixture if the voids are not small enough; this implies that closely packed fines would be needed in the mixture to avoid any segregation. The pressure at which segregation occurs must be greater than that needed to pump concrete. (2) When the fines content is too high, there could be too much frictional resistance offered by the pipe. The first type of blockage occurs in irregular or gap-graded normal strength mixtures, while the second type occurs in high strength mixtures with fillers. In order to avoid these two types of failure, the mixture should be proportioned appropriately.

• Other mixture factors that could affect pumping are the cement content, shape of aggregate, presence of admixtures such as pumping aids or air entrainment. Air entrainment is helpful in moderate amounts, but too much air can make pumping very inefficient

• When flowing concrete is being pumped, an over-cohesive mixture with high sand content is recommended. For lightweight aggregate concrete, pumping can fill up the voids in the aggregate with water, making the mixture dry.

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