this slide contains basic information about belt conveyor

1. Belt Conveyor

2. Introduction
Belt conveyor is an endless belt operating
between two or more pulleys with its load
supported on idlers.

3. Classification
According to
design &
application
General
purpose
conveyor
Special
purpose
conveyor
According to
profile path
Horizontal
type
Inclined
type

4. Parts of belt conveyor
1. Belt
2. Drive mechanism
3. Pulleys
4. Idlers
5. Loading and discharging device

5. 1.Belt
Materials :
A. Rubber
• used for bulk material
• Made up of carcass
B. Woven cloth
• Light weight material
C. Steel
• For metal industries

6. Belt
 High strength
Low mass
Low relative elongation
High elasticity longitudinally and crosswise
Low hygroscopicity
High wear resistance
Characteristics

7. 2. Drive mechanism
 For single pulley drive up to 30-50 kW is
required.
 We can provide up to 250 kW.
 Depends on pulley drive.

8. Pulleys
• Head Pulley - turns belt back around
to return - may be coupled to drive
• Tail Pulley - turns empty belt around
for loading - occasionally coupled to
drive
• Drive Pulley - Coupled to motor pulls
belt - usually special grip surface
• Snub Pulley - usually used to
change direction of belt and
increase the contact angle with the
drive pulley (more surface area to
transfer power)
• Take Up Pulley - Used to maintain
tension on a belt left loose enough
for some flexibility

9. 5. Idlers
• Supports Belt and Material Load
• Built with
– Shaft surrounded by bearings
– Then roll of steel or rubber
• Two main types
– Carrying for material and belt
– return supports belt on return trip
• Efficiency of conveyor largely dependent on this.
• Its diameter ranges from 4 to 7 inches.

10. Idler type
1. Flat belt idler
 Used for granular materials of
angle of repose not less than 35º.
 Preferred for low capacity where
inexpensive conveying is required.
2. Toughing idlers with 20º trough
 Used for conveying all kinds of
bulk material
3. Toughing idlers with 35º and 45º
trough
 Mainly used for transportation of
small particle light weight materials
like grains, cotton seed etc.
 used for carrying heavier, medium
size lumps like crushed stones.

11. 6. Loading device

12. 6. Unloading device
o More than one point discharge
o Generally used in flat and
horizontal conveyor
o Scrappers or ploughs are
diagonally mounted usually at
30º across the direction of
travel
o May damage the belt if speed
is higher than 60m/min.
Plough scrapper

13. Unloading device
o Used to discharge the
material at a number of
fixed points
o Made of two pulley
which may be fixed or
movable
Tripper

14. Design of belt conveyor
Design of belt conveyor system is based on:
Available space
Horizontal conveying length
Characteristics of material to be conveyed
Capacity requirement

15. Design parameters
1. Speed and width of belt
- Speed should not increase 3.5 m/s.
- For grain conveying: 2.5 to 2.8 m/s.
- Belt width in meter;
where is coefficient of cross sectional area of load on belt
is coefficient of load reduction of load layer cross
section on an inclined portion of conveyor

16. 2. Thickness of belt
3. Diameter of pulleys and idlers
- for rubber-fabric belt
Where is coefficient depending on strength of ply
fabric
is coefficient depending on type of pulley
I is number of plies
- For rubber-cable belt
i

17. 4. Required horsepower
- It depends on the capacity of belt conveyor.
- The capacity of belt conveyor in m³/hr is given by:
5. Belt tension
Effective tension,
kW is power in kilowatt
S is the belt speed, m/s
T = kW / S
(area of cross-section of belt, m²) * (belt speed, m/min) * 60

18. 6. Trough angle and surcharge angle in idlers
7. Torque of driving pulley
Where K =1.1 or 1.2
W= circumferential force on driving pulley

19. 8. Strength of belt
 Rubber-fabric and
rubber-cable belts can be
employed if the required
strength ranges from 1.5-
4 kN/mm.
9. Idler spacing
 Approximately equal to
width of belt
 Should not exceed 1.2
meters.

20. Advantages
 High load carrying capacity (up to 30000t/h)
 Large length of conveying path (up to 3-4 km in
single conveyor)
 Simple design
 Easy maintenance
 High reliability for operation
 More flexible

21. Disadvantages
Vertical transportation can not be done.
A separate arrangement for material
handling is required.
Hot materials can not be transported .
High initial cost for short distances.

22. Applications
• Many other functions can be performed
with the basic conveying like weighing,
sorting, picking, grading, spraying, cooling,
drying, sampling etc.
• Major role in mining.
• It can be used for special purposes like fire
resistance, wear resistance, corrosion
resistance and can be integrated with other
equipment.

23. Reference
Sahay, K.M. and Singh, K.K. (2009). “Unit
Operations of Agricultural Processing”. Vikas
publication: 287-315.
Spivakovsky, A. and Dyachkov, V. (1985). “
Conveying machines”. Mir publishers, moscow:
99-165.