BELT CONVEYOR DESIGN

2. Continuous Conveying Machines
CONVEYERS WITH TRACTIVE ELEMENT BELT CONVEYRS
APRON CONVEYRS
WITH CONTROLLED FLIGHT
LOAD CARRYING
PUSH BAR
BUCKET ELEVATORS
FLIGHT ELEVATORS
CRADLE ELEVATORS
WITHOUT TRACTIVE ELEMENT SCREW CONVEYERS
OSCILLATING CONVEYRS
ROLLER CONVEYRS
WITH MAGNET MOVING
FORCES
PNEUMATIC
TRANSPORT DEVICES
FOR CONVEYING BULK LOADS
AIR PRESSURE CONVEYING
BULK LOADS
HYDRAULIC DEVICES GRAVITY FLOW
PRESSURSED FLOW

3. Selection the type of conveying machines is
based on following parameters
• Characteristics of load to be transmitted
• Requisite through put capacity
• The direction, length and configuration of load
transfer path
• Methods of loading and reloading
• Compatibility of production process with
transfer path.
• Economic factors

4. Importance of belt conveyers
• Belt conveyers are employed for conveying various bulk and
unit loads along horizontal or slightly inclined path and for
transporting articles between various operations in
production flow lines.
• They have wide applications in all the branches of industry like
foundry, fuel supply for power plants, mining industries etc.
• It is used as basic principle component of some complex
machines such as excavators, conveyer bridges etc.
• It has high load carrying capacity up to 30000T/Hour and large
length of conveying path 3-4 kilometers in single conveyer
path. With multiple up to 100km possible.
• Simple design, easy maintenance and high reliability of
operation.

5. Components of belt conveyors

6. Different possible arrangements are as
follows

7. According to orientation
With Single drive Pulley

9. According to orientation
With Double drive Pulley

13. • Angle of inclination of conveyer to the horizontal
depends upon
– Coefficient of load friction against the belt motion
(type of material and form and surface of belt)
– Angle of repose of bulk load
– Method of loading
– Speed of belt
• General safe range is 10-15 Degree, Such large
margin is needed because on sagging portion
angle of inclination is more.

14. Important Points regarding belt
• In belt conveyers belt has to provide tractive
force as well as to support load.
• Standard belts are manufactured following
standard widths
– 300,400,500,650,800,1000,1200,1400,1600,2000,250
0,3000,4000,5000..
• Belt conveyer should have high strength, low
mass, low relative elongation, high elasticity, low
hygroscopicity, high wear resistance, chemically
inert.

15. Composition of belt used for conveyer
• It is composed of tractive
carcass A covered from all
sides by an elastic
protective layer B as
shown.
• Carcass A absorb
longitudinal stress While
filler protects against
moisture and chemical
damage.
• Type used depend upon
apllication

16. Types of troughing idlers

18. EACH LINK WITH INDIVIDUAL ROLLER AND TWO BEARINGS
LENGTH OF CONVEYING PATH CAN BE INCREASED AT ANY TIME

19. ROLLER SUPPORT WITH FLEXIBLE
SHAFT
DRAWBACK IS LARGE LONGITUDINAL OSCILLATIONS

21. • Diameter of roller should satisfy
– The moment of friction of the belt on a roller should be
greater than moment of friction in the bearing seals
– With increase in centrifugal force material should not
thrown away.
• Diameter of roller increase with speed of belt,
density of material, lump size of load.
• In three roller troughing support the vertical load
on middle roller is about 70% of total load and 15%
on each side rollers.
• The spacing between the roller supports for
carrying run is chosen on the basis of characteristic
of material to be conveyed.
• For the return run spacing between return roller is
taken around 2 to 2.5 times greater than carrying
side.

22. • Troughing angle of side roller is usually 20 to
30 deg for all types of loads and any width of
belt.
• For light loads with lesser density material
troughing angle can be increased up to 45 to
60 deg.
• With the increase in trough angle capacity of
conveyer increased.

23. • Single pulley drives of a lower power up to 30 to 50 Kw
equipped with reduction gear box.
• Two drive pulleys with single motor is used with differential
gear box
• Drawback of double pulley drive can be reduced by
increasing angle of lap by employing snub pulley.
• Tractive force can be increased by providing grooves on
drive pulley.

25. Unloading devices

26. Cleaning devices

27. Tensioning devices or take up systems
• These devices are of following devices
– Screw type (for conveying length up to 60 meters)
– Hydraulic (rarely used, costly)
– Gravity type (for conveying length up to 60 to 500
meters)
– Spring biased gravity type.
– Gravity winch type
– Gravity tension sensor
– Winch type

29. Gravity winch type