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PRESENTATION ON STUDY ON conveyors SUBMITTED BY :- Er. OM SURYAWANSHI 9302528033

Conveyors by om

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Page 1: Conveyors by om

PRESENTATION ON

STUDY ON conveyors

SUBMITTED BY :- Er. OM SURYAWANSHI

9302528033

Page 2: Conveyors by om

Material handling Equipment

Material handling includes a number of operations that can be

executed either by hand (manual) or by mechanical means or

devices to convey material and to reduce the human drudgery.

1. Belt conveyor

2. Bucket elevator

3. Screw conveyor

4. Chain Conveyor

5. Pneumatic conveyor

Page 3: Conveyors by om

Belt conveyors

A belt conveyor is an endless belt operating between two pulleys with its load supported on idlers. Generally, for grain conveying, belt speed of 2.5 to 2.8 m/s is recommended.

Capacity, m2/h = (area of cross section-m2)X(belt speed, m/min)X 6O

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Belt conveyor idlers

1. The flat belt idlers are used for

granular materials having an angle of

repose of not less than 35°.

2. Troughing idlers with 20° trough is

used for conveying all kinds of bulk

materials.

3. Troughing idlers with 35° and 45°

trough angle is mainly used for

transportation of small particle light

weight materials like grain, cotton

seed etc

Page 5: Conveyors by om

Idler Spacing

The space between the successive idlers should be

approximately equal to the width of belt. The spacing should not

exceed 1·2 metres.

Belt tension:-

The tension developed at the drive pulley in transmitting the

required power to move the loaded belt is known as effective

tension.

Effective tensoin, T =Power, KW/belt speed, m/s.

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Bucket Elevator

The vertical lift of the elevator

may range between few metres to

more than 50 m. Capacities of

bucket elevators may vary

from 2 to 1000 t/hr

(1) spaced bucket elevators and

(2)continuous bucket elevators.

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The spaced bucket elevators are further classified as,

(1) centrifugal discharge elevators,

(2) positive-discharge elevators,

(3) marine leg elevators and

(4) high-speed elevators.

The continuous bucket elevators are classified as

(1) super capacity bucket elevators and

(2) internal-discharge bucket elevators.

The product flow is discharged either by means of gravity or centrifugal force.

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The spaced bucket centrifugal discharge type is most commonly used for elevating the grains.

1. low speed gravitational discharge 2. high speed centrifugal discharge

Page 9: Conveyors by om

Elevator capacity, t/hr = capacity, m3x No. of bucket per m. of beltx belt speed, m/min.x 6O

Capacity, t/hr = Capacity, m3/hr x material density, kg/m3÷ 1000

The bucket elevator's capacity may be calculated by the following equation.

The bucket elevator's capacity mainly depends on

Bucket size

Conveying speed

Bucket design

Spacing

Way of loading and unloading

The characteristic of bulk material

Page 10: Conveyors by om

The main parts of a bucket elevator are, (1) elevator head section, (2) elevator boot section, (3) elevator legs, (4) belts for bucket elevator and (5) buckets.

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Elevator Belts The total stretch of the belt under maximum load should not exceed 1-2 % of the belt length

Buckets The top angle is generally taken as 80° while the bottom angle is between 20-30°.

Buckets

Elevator Belts

Page 12: Conveyors by om

HP requirement

Hp = QHF/ 4562

where,

Q = capacity of bucket elevator, kg/min

H = lift of elevator, m

F = factor; 1.5 for elevators loaded on the up side and

1.2 for elevators loaded on the bottom side

The theoretical horsepower should be increased 10-15% to

provide for friction and power requirements for loading, power

transmission and drive losses.

Page 13: Conveyors by om

Screw Conveyor

The screw conveyor consists of a tubular or U-shaped

trough in which a shaft with spiral screw revolves.

Page 14: Conveyors by om

Screw conveyor details

The screw conveyor is generally used to move grains

horizontally. However, it can also be used at any angle up to 90°

from the horizontal, but the capacity correspondingly reduced as

per the inclination of conveyance.

The pitch of a standard screw which is the distance from the

centre of one thread to the centre of the next thread is equal to its

diameter.

Screw conveyor details

Page 15: Conveyors by om

Capacity Q, m3/hr = 47.2 (D2 - d2) X P x n

where, D = screw diameter, m d = shaft diameter, m p = pitch, m n = rpm

Capacity of the screw conveyor can be given by the following equation :-

Horse power = QLWF/4560

where, Q = conveyor capacity, m3/hr L = conveyor length, m W = bulk material weight, kg/m3 F = material factor (for paddy 0.4)

Power requirement

Page 16: Conveyors by om

Pneumatic Conveyor :-

The pneumatic conveyor moves

granular materials in a closed duct by

a high velocity air stream.

The pneumatic conveying system

needs a source of air blowing or

suction, means of feeding the

product into the conveyor,

For dispersion of bulk material, air

velocities in the range of 15-30 m/s is

necessary.

Page 17: Conveyors by om

Chain Conveyor

A chain is a reliable machine component, which transmits

power by means of tensile forces, and is used primarily for

power transmission and conveyance systems.

Types of Chain conveyor

Cast iron chain

Cast steel chain

Forged chain

Steel chain

Plastic chain

Page 18: Conveyors by om