The document discusses different types of belt drives and their applications. It describes round belts, V-belts, flat belts, and toothed belts used in various mechanical devices. The materials used to make belts include leather, cotton, rubber, and balata. Belt drives transmit power efficiently between parallel or non-parallel shafts using pulleys. They are widely used in applications like automobiles, treadmills, and sewing machines. Rope drives are also discussed for transmitting large amounts of power over long distances.

1. Presented By:

2. Belts
 Introduction
 Types of belts
 Material s
 Belt Drives
 Applications
 Advantages & Disadvantages
Rope Drives

3.  A belt is a loop of flexible material used to link two or
more rotating shaft mechanically, most often parallel.
 Belts may be used as a source of motion, to transmit
power efficiently, or to track relative movement.
 Belts are looped over pulleys and may have a twist
between the pulleys, and the shafts need not be parallel.
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4. Round Belt:
Round belts are generally made of rubber. This type
of belt is generally used for light loads, such as in a sewing machine or
a vacuum cleaner.

5. V belts are arguably the most widely used belts in
industry. V belts have a V shaped cross-section, which against
the side of V pulley under tension. The V shaped cross-section
prevents belt from slipping off.

6. Flat belts are designed for light-duty power transmission
and high-performance conveying. They are best-suited for
applications with smaller pulleys and large central distances. Flat
belts can connect inside and outside pulleys and can come in both
endless and jointed construction. They have a high power
transmission efficiency, are cost effective, and are easy to use and
install.

7. It is a flexible belt with teeth moulded onto its inner surface.
It is designed to run over matching toothed pulleys
or sprockets. Toothed belts are used in a wide array of in
mechanical devices, where high-power transmission is desired.

8.  Leather:
 The leather is the most significant material for flat belts. Leather belts
are made from steer leather (cut from either side of the backbone of a
steer).
 The fibers on the flesh side are stronger and parallel to the surface
while fibers on the hair side are smoother and perpendicular to the
surface.

9.  Cotton or fabric belts
The fabric belts are commonly used for temporary
application. Most fabric belts are made by the folding cotton duck
to three or more layers and stitching together. The fabric belts are
commonly used for temporary application. Most fabric belts are
made by the folding cotton duck to three or more layers and
stitching together.
 Rubber belt:
They are made by impregnating fabric or canvas with
rubber and have a thin layer of rubber on the surface of the
belt. These types of the belt are very flexible, and they can be
easily made endless.
 Balata belts:
They are similar to the rubber belt but stronger than
rubber belt. In this type, balata gum is used instead of
rubber. Balata belt is waterproof and has high resistance to
acidic, alkaline materials, so they are used for food packing
conveyor.

10.  A belt drive consists of two pulleys attached to each shaft and
an endless belt wrapped around them with some initial
tension. Power is transmitted from the driver pulley to the belt
and from the belt to the driven pulley with the help of friction.
Friction between belt and pulley surface limits the maximum
power that can be transmitted. If this limiting value is
exceeded, belt starts slipping. Belts have limited life and
should be periodically inspected for wear, aging, and loss of
elasticity and should be replaced at the first sign of
deterioration.

13. Example-1 v
Question: What is the lenght of the belt if the conters are 2000mm in
apart?
DATA:
D=600mm
d=400mm
C=2000mm
𝜋=3,14
L=?

14.  SOLUTİON
v
L=2x2000+1,57(600+400)+(600+400)
(4x2000)
L=5695mm

15.  Belt drives are different from the belts, these are described as
combination of pulleys according to their position and also
their carrying or transmitting power from one pulley to
another pulley.
 Three main types are given as follows:
1. Light drives: These are used to transmit small
powers at belt speeds upto about 10 m/s, as in
agricultural machines and small machine tools.
2. Medium drives: These are used to transmit
medium power at belt speeds over 10 m/s but up
to 22 m/s, as in machine tools

16.  Heavy drives: These are used to transmit
large powers at belt speeds above 22
m/s, as in compressors and generators.
 Examples:
v

17. Automobile Timing Belt:
The classic example of a real life timing
belt drive system is the timing belt/cam
belt system that is present in most
on roads all over the world.
Treadmills:
The treadmill is another great example of a belt
driven mechanism. The belt in this drive system is
not to be confused the tread on which the
runner directly runs; rather the belt drive system
is the toothed.
Sewing Machines:
Another everyday example of a belt drive system
is not quite as exciting or as obvious as the
treadmill or automobile.

18.  Belt drives are simple and economical than ropes and chains.
 They don’t need parallel shafts.
 Belts drives are provided with overload and jam protection.
 Noise and vibration are damped out. Machinery life is
increased because load fluctuations are shock-absorbed.
 They are lubrication-free. They require less maintenance cost.
 Belt drives are highly efficient in use (up to 98%, usually 95%).
 They are very economical when the distance between shafts is
very large.

19.  In Belt drives, angular velocity ratio is not necessarily constant or
equal to the pulley diameters, because of slipping and stretching.
 Heat buildup occurs. Speed is limited to usually 35 meters per
second. Power
 transmission is limited to 370 kilowatts.
 Operating temperatures are usually restricted to –35 to 85°C.
 Some adjustment of center distance or use of an idler pulley is
necessary for wearing and stretching of belt drive compensation.
 Belts can be noisy; also loose or worn belts can be a major cause of
machinery vibration.
 Belts are easily damaged by oil, grease, abrasives, some chemicals,
and heat

20. • The rope drives are widely used where a large amount of
power is to be
• transmitted, from one pulley to another, over a considerable
distance.
• It may be noted that the use of flat belts is limited for the
transmission of moderate power from one pulley to another
when the two pulleys are not more than 8 metres apart.
• If large amounts of power are to be transmitted, by the flat
belt, then it would result in excessive belt cross-section.

21. 1. Fiber Ropes: 2. Wire Ropes.

22.  The ropes for transmitting power are usually made from
fibrous materials such as hemp, manila and cotton.
 Since the hemp and manila fibers .are rough, therefore the
ropes made from these fibers are not very flexible and
possesses poor mechanical properties
 In order to minimize this defect, the rope fibers are lubricated
with a tar,
 tallow or graphite.
 The fiber ropes are suitable only for hand operated hoisting
machinery and as tie ropes for lifting tackle, hooks etc.
v v

23.  Wire rope is several strands of metal wire twisted into a helix
forming a composite "rope", in a pattern known as "laid rope".
Larger diameter wire rope consists of multiple strands of such
laid rope in a pattern known as "cable laid".
 Inside view of a wind turbine tower, showing the wire
ropes used as tendons

24. Advantages:
 Significant power transmission.
 It can be used for long distance.
 Ropes are strong and flexible.
 Provides smooth and quiet operation.
Disadvantages:
 Internal failure of the rope has no sign on
external, so it if often get unnoticed.
 Corrosion of wire rope.