Material handling equipments

Material Handling Material Handling EquipmentsEquipments

Presented byPresented byP.ANBARASANP.ANBARASAN

B.Tech(agri.engg)B.Tech(agri.engg)

P.ANBARASANP.ANBARASAN

INTRODUCTIONINTRODUCTIONMaterial handling includes a number of operations that can Material handling includes a number of operations that can

be executed either by hand (manual) or by mechanical means be executed either by hand (manual) or by mechanical means or devices to convey material and to reduce the human or devices to convey material and to reduce the human drudgery. drudgery.

Mechanical handling devices aim to lighten the work of Mechanical handling devices aim to lighten the work of human labour.human labour.


The most common types of mechanical devices for grain The most common types of mechanical devices for grain handling are;handling are;

1. Belt conveyor1. Belt conveyor

2. Bucket elevator2. Bucket elevator

3. Screw conveyor3. Screw conveyor

4. Pneumatic conveyor4. Pneumatic conveyor


Belt conveyorBelt conveyorA belt conveyor is an endless belt operating between two or more A belt conveyor is an endless belt operating between two or more pulleys.pulleys.The belt and its load are supported on idlers. The belt and its load are supported on idlers. The belt may be flat for transporting bagged material or V-shaped The belt may be flat for transporting bagged material or V-shaped for moving bulk grains. for moving bulk grains. The belt conveyor consists of a belt, drive The belt conveyor consists of a belt, drive mechanism and end pulleys, idlers andmechanism and end pulleys, idlers and loading and discharge devicesloading and discharge devices. .


To avoid spillage, the belt speed of 2.5 – 2.8 m/s is To avoid spillage, the belt speed of 2.5 – 2.8 m/s is recommended for transportation of grains. recommended for transportation of grains.

The drive mechanism should be provided at the discharge end The drive mechanism should be provided at the discharge end of the belt. of the belt.

The conventional belt pulley drive mechanism must provide The conventional belt pulley drive mechanism must provide enough contact surfaces with the belt. Belt can be run at enough contact surfaces with the belt. Belt can be run at higher speeds, so, large carrying capacities are possible.higher speeds, so, large carrying capacities are possible.

Horizontally the material can be transported to longer Horizontally the material can be transported to longer distance but there is a limit to carry the material on elevation.distance but there is a limit to carry the material on elevation.


A properly designed and maintained belt conveyor system has A properly designed and maintained belt conveyor system has longer service life.longer service life.

It has high initial installation cost and low operating cost.It has high initial installation cost and low operating cost.High capacity belt conveyors have a conveying capacity of High capacity belt conveyors have a conveying capacity of

2000 tonnes grain per hour with belt speed of 3.5m/s.2000 tonnes grain per hour with belt speed of 3.5m/s.The efficiency of belt conveyor is largely depend on idlers.The efficiency of belt conveyor is largely depend on idlers.For higher efficiency of belt conveying systems, the idlers For higher efficiency of belt conveying systems, the idlers

must be accurately made and provide a rigid framework.must be accurately made and provide a rigid framework.


belt conveyor idlers:belt conveyor idlers: Flat belt idler Flat belt idler

-- granular material(angle of repose >35)-- granular material(angle of repose >35)

Idler for 200 Troughed beltTroughed belt-- all kind of bulk materials-- all kind of bulk materials

Idler for 350 and 450 Troughed beltTroughed belt--small praticle light weight material --small praticle light weight material

like grain, cotton seed.like grain, cotton seed.P.ANBARASANP.ANBARASAN

Bucket elevatorBucket elevatorThe bucket elevator is a very efficient device for the vertical

conveyance of bulk grains.Bucket elevators are more versatile lifting equipment for in

the food processing industry for lifting materials either vertically or in an inclined position.

A bucket elevator consists of buckets attached to a chain or belt that revolves around two pulleys one at top end and the other at bottom end.


The main parts of a bucket elevator 1. Elevator head section2. Elevator legs3. Belts for bucket elevator4. Buckets

5. Elevator boot section


The top pulley is driven pulley while the lower pulley is return and tension pulley.

Bucket elevator carry the materials in closed or in open form.The free flowing solids are fed at the bottom continuously by means

of some feeding arrangement into the bucket under the feeding point.The vertical lift of the elevator range between few metres to more than 50 mCapacities of bucket elevators may vary from 2 to 1000 t/hr


Bucket elevators are broadly classified into two general types, (1) spaced bucket elevators and (2) continuous bucket elevators.The spaced-bucket centrifugal discharge type is most commonly used for elevating the grains..It is a fairly cheap means of vertical conveyance.It requires limited horizontal space and the operation of conveying is enclosed in housing, thus it is dust free and fairly quite


screw conveyorscrew conveyorThe screw conveyor consists of a tubular or u-shaped trough The screw conveyor consists of a tubular or u-shaped trough

in which a shaft with spiral screw revolves.in which a shaft with spiral screw revolves.The rotation of screw pushes the grain along the trough.The rotation of screw pushes the grain along the trough.Designed for clockwise and anticlockwise direction. – Designed for clockwise and anticlockwise direction. –

capacity not affected.capacity not affected.Screw conveyor is also known as Screw conveyor is also known as auger conveyor.auger conveyor.


The conveyor screw imports a smooth positive motion to the material The conveyor screw imports a smooth positive motion to the material

as it rotates with in trough.as it rotates with in trough.

Hangers provide support, maintain alignment and serve as bearing Hangers provide support, maintain alignment and serve as bearing

surfacessurfaces. .



Pneumatic conveyorPneumatic conveying is an excellent method for transportation of

powders which are easily flowable.Pneumatic conveying is a continuous and flexible transportation

method. The conveying system uses a gas, usually air, to transport the

material. Granular and powder foods like cereals, seeds, pulses, sugar, or

any kind of ground products in the form of particulates or powders can be conveniently transported by pneumatic conveying systems.


The pneumatic conveyor moves the materials in a closed duct by a high velocity air stream.

The material is carried in pipelines either by suction or blowing pressure of air stream.

For dispersion of bulk material, air velocities in the range of 15-30 m/s is necessary.

The pneumatic conveying system needs a source of air blowing or suction, means of feeding the product into the conveyor, ducts and a cyclone or receiving hopper for collection of product.


A schematic representation of pneumatic conveyor is shown in figure where the material is fed from a storage silo through a rotary valve

The speed of the valve controls the flow rate of the feed. The material is kept in suspension along with air in the pipelines,

and transported through the pipelines upto the point of destination. The destination point could be the processing equipment.

These conveyors are also used for unloading the materials from the ships to the place of storage, or into the silos.


The distance of transportation can vary anywhere between 70-600 m. usually air pressures are maintained at 700 kPa (7 atm). Higher air pressures upto 900-1000 kPa are also used, and materials can be transported upto 2-3 km.

Pneumatic conveying can be done by the following methods.Pneumatic conveying under vacuumPneumatic conveying under pressure vacuum combination Pneumatic conveying by fluidization method


In the fluidization method, the material is kept in a state of fluidization by blowing air from the bottom. The material is transported either by means of entrainment or by the vibration of the bed which is known as vibro-fluidized bed.

In the pneumatic transportation systems, pressure and flow rate of air should be sufficient enough so that the material is kept in a state of suspension. If it is less, the material will start settling




Material handling equipments

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