SPROCKET

ATB-237 DESIGN PROJECT REPORT

SUBMITTED BY
E. NISHANTH (0017104091)
S. KISHORE KUMAR (0017105006)
AKASH ROHITH (0016105006)

In partial fulfilment for the award of the degree of

BACHELOR OF TECHNOLOGY
IN
AUTOMOBILE ENGINEERING

DEPARTMENT OF AUTOMOBILE ENGINEERING

SCHOOL OF MECHANICAL SCIENCES
HINDUSTAN INSTITUTE OF TECHNOLOGY AND SCIENCE
PADUR, CHENNAI-60310

April 2019
 BONAFIDE CERTIFICATE
Certified that this Project Report titled “DESIGN OF SPROCKET” is the
Bonafide work NISHANTH E (0017104091), S.KISHORE KUMAR
(0017105006), AKASH ROHITH (0016105006) who carried out this design
project work under my supervision. Certified further that to the best of my
knowledge the work reported here does not part of any other project/research
work on the basis of which a degree or award was conferred on an earlier occasion
on this or any other candidate.

Staff In Charge

INTERNAL EXAMINER EXTERNAL EXAMINER

Name: Name:

Designation: Designation:

Institution Name:

THE DESIGN PROJECT EXAMINATION HELD ON -

 ACKNOWLEDGEMENT

I express my heartfelt thanks to our Honourable chancellor, Dr. Elizabeth Verghese for her
consent support and encouragement in completing the project.

I would like to thanks our Honourable Pro chancellor, Dr. Anand Jacob Verghese , for his
continuous motivation during the course of this project work.

I extend my gracious thanks to our Vice chancellor, Prof. Dr. Kuncheria P. Isaac, PhD, for his
support and guidance towards this project.

I express my gratitude and heart thanks to our HEAD OF THE DEPARTMENT Dr. M
JAIKUMAR, Ph.D., for encouraging into this project work with numerous ideas and advices
in completing this project work on time.

I express my gratitude and heartfelt thanks to my project guide Mr.S NANDAKUMAR, for
encouraging me into this project work with numerous ideas and advices in completing this
project work on time.

Finally I take this opportunity to thank all staff members in the Department of Automobile
Engineering for their continuous review and suggestion in completing this project work.
ABSTRACT

Sprockets are most widely used in automobile sector and in machinery. These are used in two
wheelers and four wheelers such as bikes, cycles, cars and other mechanism either to transmit
revolving motion between two shafts wherever gears are incompatible or to communicate
undeviating motion to a pathway etc. They exist in various dimensions, teeth number and are
made of different materials. Sometimes faulty chains quickly wear the sprocket. Possible
causes of this problems are significant overload, breakage, high impact pressure, excessive
chain wear far beyond replacement level, combination of worn chain with new sprockets etc.
To ensure efficient power transmission chain sprocket should be properly designed and
manufactured. There is a possibility of weight reduction in chain drive sprocket. In this paper,
a study of design optimization of sprocket using different processes and techniques is studied.
This paper reviews the designing of chain sprocket, analysis using FEA and using the results
from FEA how the optimization of sprocket for weight reduction has been done. Mostly
researchers have used different grades of steel as their base material and re-designed the
sprocket by using different CAD software, few have used composite materials like Carbon
Fiber or Nylon66GF30 also as an alternative to steel and compared to earlier research. Some
has given heat treatment and other types of chemical treatment to the sprocket to enhance its
mechanical properties. From the review, it is concluded that no work is done in re-designing
of chain sprocket and optimizing its weight and performance.
 TABLE OF CONTENT
CHAPTER NO. TITLE PG.NO
I 1. INTRODUCTION OF SPROCKET
1.2. SPROCKET TYPES
1.2.1. CHAIN DRIVE
1.2.2. ROLLER CHAIN
1.2.3. RACK AND PINION
1.2.4. TOOTHED BELT
1.3. SHAPES OF SPROCKET

II LITERATURE REVIEW 7
2.1 SPROCKET DESIGN
2.2 SHAPE OF SPROCKET
2.2.1 CAST SPROCKET ARM BODY
2.2.2 FLAT STRUCTURE WITH NO HUB
2.2.3 FLAT STRUCTURE WITH HUBS
2.3 VARIOUS DEVELOPMENT IN SPROCKET

III METHODOLOGY 11
3.1 FLOW CHART 11
3.1.1 DIMENSIONS OF THE SPROCKET 12
3.2 SPROCKET REQUIREMENT 13
IV RESULT AND DISSCUSION 14
4.1 SPROCKET DRAFT 14
4.1.1 MATERIAL SELECTED 14
4.1.2 DESIGN CALCULATION 15
V CONCLUSION 18
 LIST OF FIGURES

1.1 SPROCKET

1.2.1 CHAIN DRIVE

1.2.2 ROLLER CHAIN

1.2.3 RACK AND PINION

1.2.4 TOOTHED BELT

2.1.2

1. CAST ARM SPROCKET BODY

2. FLANGED STRUCTURE WITH NO HUBS

3. FLANGED STRUCTURE WITH HUB

3.1.1 ALL SIDES OF SPROCKET

4.1 DRAFT OF SPROCKET

4.2 SPROCKET DESIGN IN CREO

 CHAPTER - I

INTRODUCTION

Sprockets are used in bicycles, motorcycles, cars, tracked vehicles, and other
machinery either to transmit rotary motion between two shafts where gears are
unsuitable or to impart linear motion to a track, tape etc. Perhaps the most
common form of sprocket may be found in the bicycle, in which the pedal shaft
carries a large sprocket-wheel, which drives a chain, which, in turn, drives a small
sprocket on the axle of the rear wheel. Early automobiles were also largely driven
by sprocket and chain mechanism, a practice largely copied from bicycles.Within
international standards sprockets are conceptually basic mechanical devices.
However, their versatility leads to many contrasting style. Sprockets can be
supplied in various materials and styles, depending upon the application and
severity of service requirements. Generally, there are two major ways of
categorizing sprockets; by general form and form of the hub. show sprocket
classification by general form while. shows classification based on hub form. For
most applications, fabricated steel. sprockets are recommended as offering the
best combination of performance, availability, and price. Fabricated steel
sprockets can be provided for every chain tooth combination and are readily
available
1.SPROCKET

FIG 1.1 SPROCKET

A sprocket or sprocket-wheel is a profiled wheel with teeth, or cogs, that mesh

with a chain, track or other perforated or indented material. The name 'sprocket'
applies generally to any wheel upon which radial projections engage a chain
passing over it. It is distinguished from a gear in that sprockets are never meshed
together directly, and differs from a pulley in that sprockets have teeth and pulleys
are smooth. Sprockets are of various designs, a maximum of efficiency being
claimed for each by its originator. Sprockets typically do not have a flange. Some
sprockets used with timing belts have flanges to keep the timing belt centered.
Sprockets are also used for power transmission from one shaft to another where
slippage is not admissible, sprocket chains being used instead of belts or ropes
and sprocket-wheels instead of pulleys. They can be run at high speed and some
forms of chain are so constructed as to be noiseless even at high speed.

2
1.2 SPROCKET TYPES

1.2.1 CHAIN DRIVE

Chain drive is a way of transmitting mechanical power from one place to
another. It is often used to convey power to the wheels of a vehicle, particularly
bicycles and motorcycles. It is also used in a wide variety of machines besides
vehicles.

FIG 1.2.1 CHAIN DRIVE

1.2.2ROLLER CHAIN
It consists of a series of short cylindrical rollers held together by side links. It is
driven by a toothed wheel called a sprocket. It is a simple, reliable, and
efficient means of power transmission. Roller chain or bush roller chain is the
type of chain drive most commonly used for transmission of mechanical power
on many kinds of domestic, industrial and agricultural machinery, including
conveyers, wire and tube drawing machines, printing presses, cars, motorcycles,
and bicycles.

FIG 1.2.2 ROLLER CHAIN

3
1.2.3 RACK AND PINION
A rack and pinion is a type of linear actuator that comprises a circular gear (the
pinion) engaging a linear gear (the rack), which operate to translate rotational
motion into linear motion. Driving the pinion into rotation causes the rack to be
driven linearly. Driving the rack linearly will cause the pinion to be driven into a
rotation

FIG 1.2.3 RACK AND PINION

.
1.2.4 TOOTHED BELT
A toothed belt; timing belt; cogged belt; cog belt; or synchronous belt 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.

FIG 1.2.4 TOOTHED BELT

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1.3 SHAPES OF SPROCKET
 Cast sprocket arm body

 Cast split arm body

 Cast steel plate body

 Fabricated steel with holes

 Fabricated steel split sprocket

 Fabricated steel plate body

 Shear pin sprocket

 Drum flanged body

 Flanged rim sprocket

 Flat structure with no hub

 Flat structure with hub

5
 CHAPTER II
LITERATURE REVIEW

First Known Use of sprocket is in the year 1886, the term 'sprocket' originally
applied to the projection from the wheel that caught on the chain and provided
the drive to it. The overall wheel was then termed a 'sprocket wheel'. With time
and common use of these devices, the overall wheel became known as a sprocket.
The earlier uses would now be seen as archaic. A toothed wheel whose teeth
engage the links of a chain , a cylinder with teeth around the circumference at
either end that project through perforations in something (such as motion-picture
film) to move it through a mechanism (such as a projector).

They used CATIA and ANSYS for designing and analyzing the result
respectively. They determined the equivalent stress and strain using base material
like SS304, then changed the material and tests on PEEK, PI and PPS material
was taken results were compared. They found that those high performance
engineering plastic materials can be used in the manufacturing of Sprocket in the
viewpoint of equivalent stress and equivalent elastic strain. The main thing was
cost, and they found that the cost of PPS is very lesser than other plastic material
even much lesser than the cost of SS 304. Therefore, PPS was one of the best
Alternate material for SS 304.

2.1. SPROCKET DESIGN :

Based on Literature Review, different design of sprocket shape optimization

processes and techniques was used by different researchers. Some of them re-
designed the chain sprocket, analysis using FEA and using the results from FEA
they optimized the weight of sprocket. Mostly researchers have used different
grades of steel as their base material and re-designed the sprocket by using
different CAD software, few have used composite materials like Carbon Fiber or
Nylon66GF30 also as an alternative to steel and compared to earlier research.
Some has given heat treatment and other types of chemical treatment to the
sprocket to enhance its mechanical properties. For this review, many international
and national papers were helpful. Worldwide researchers have applied the efforts
to design and tried to optimize the weight of chain sprocket. They tried to
diagnose the faults by using the simple techniques. They found out the major
breakdowns in mechanisms due to sprockets failure causing production losses to
the company and suggested counter measures by which these problem can be
reduced. They identified the root causes of breakdowns using cause and effect
diagram. Finally, they studied diagnosis of the faults for eliminating causes. By
using the design sprockets for the particular causes, it would help to reduce the
defects like wear in the sprockets, reduction of Noise in the drive by using the
proper chain for the alignments, reduction of vibration in the sprockets using
modal analysis, 26 tooth were preferred according to the polygonal action found
in the sprockets and chain can be maintained

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2.1.2 TYPES OF SPROCKET SHAPE :

1. CAST ARM SPROCKET BODY :

Cast Arm Body is often used in larger diameter sprockets. The arms are
advantageous because they reduce the weight as well as the cost. The split
style sprocket eases maintenance and installation. The sprocket can be
removed without having to disassemble an entire system.

FIG 2.1.2- (1) CAST ARM SPROCKET BODY

2. FLANGED STRUCTURE WITH NO HUBS :
Plate body with no hubs sprockets are produced with plate type bodies as
shown. Few spoked sprockets are offered due to strength limitations of this
type design.

FIG 2.1.2- (2) FLANGED STRUCTURE WITH NO HUB

As space permits, many smaller sprockets are made with cam-shaped hubs,
which give additional strength over the keyway, but reduces weight
compared to conventional round hubs of the same diameter.

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3.FLANGED STRUCTURE WITH HUBS :

Plate body with Lightening Holes Where space permits, larger sprockets are
made with lightening holes cast through the body to reduce weight and facilitate
handling. Standard round hubs are used on most larger sprockets, with diameters
of hubs as appropriate according to chain type and AnSI hub specifications. This
allows each tooth to contact the chain only every other revolution. Wear life of
the sprocket is effectively doubled.

FIG 2.1.2- (3) FLANGED STRUCTURE WITH HUB

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 CHAPTER III

METHODOLOGY

START

BASIC CONCEPT OF SPROCKET DESIGN

SELECTION OF SPROCKET TYPE

BASIC SHAPE OF THE SPROCKET

DIMENSIONS OF SPROCKET

DRAFTING THE SPROCKET

DESIGNING USING PARAMATIC SOFTWARE

RESULT AND DISCUSSION

CONCLUSION

END

Fig (3.1) FLOWCHART OF SPROCKET

VIEW DIMENSION
TOP VIEW Width of teeth face = 16mm
SIDE VIEW i)Width of teeth face = 16mm
ii)space between two teeth =
49.45mm
FRONT VIEW i) Total dia of sprocket = 230 mm
ii) Distance between placing hub of
sprocket to whole sprocket =182
mm
iii) Diameter of the fastening hole =
20mm
iv) Height from the top part of
sprocket teeth to circular sprocket
= 30mm
v) Dia of flanging holes = 52.04mm
vi) Tooth thickness = 20mm

Table 3.1.1 – DIMENSIONS OF THE SPROCKET

STEP 1 : Draw the measurements from the sprocket, keep the midpoint as
the reference and draw the measurements

STEP 2 : Draw a circle with 230mm diameter and extrude it to 8.50mm

STEP 3 : Draw the inner circle of 52mm

STEP 4 : Draw the fastening holes with dia of 8mm spacing 25mm from
centre small hole

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STEP 5 : Draw flanging holes for dia 52.02 draw the same for 360 degrees

STEP 6 : Extrude the teeth of height 30mm , width of face 16mm and tooth
thickness 20mm.

STEP 7 : Now with 49.45mm gap draw the teeth for 360 degrees by
extrusion

FIG 3.1.1 All sides of sprocket

3.2 Sprocket requirements

1.Sprockets are also used for power transmission from one shaft to another where
slippage is not admissible, sprocket chains being used instead of belts or ropes
and sprocket-wheels instead of pulleys.

2.They can be run at high speed and some forms of chain are so constructed as
to be noiseless even at high speed.

3. It is often used to convey power to the wheels of a vehicle, particularly

bicycles and motorcycles.

12
3.3 Fastening hole requirement

Fastening hole varies from vehicle to vehicle and

based on the size of hub fastening hole size should be set.

FASTENING HOLE ASPECT :

1. Fastening hole tend to be fit sprocket with the wheel arch of motorcycle,
2. They has to be set in proper tight so that sprocket doesn’t have play at
all when fixed to motorcycle.

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 CHAPTER IV
RESULT AND DISSCUSTION

Fig (4.1) Draft of the Sprocket

4.1 SPROCKET DRAFT – Layout of sprocket

4.1.1 MATERIAL SELECTED- cast iron

4.1.2 DESIGN CALCULATION

Fig (4.2) sprocket designed in Creo

P = Chain Pitch

N = Number of Teeth

Dr = Roller Diameter

Ds = (Seating curve diameter) = 1.0005 Dr + 0.003 R = Ds/2 = 0.5025 Dr +

0.0015 A = N + 60.35 B = N − 56.18

ac = 0.8 x Dr M = 0.8 x Dr cos( N + 60.35 )

15
T = 0.8 x Dr sin ( N+ 60.35 ) E = 1.3025 Dr + 0.0015

Chordal Length of Arc xy = (2.605 Dr + 0.003) sin ( N – 28.9 ) (0.8sin x18 64

1.4 sin170))

Dr ab = 1.4 Dr W = 1.4 Dr N 180

 Velocity ratio : N1/N2 = T2/T1

where,

N1 – speed of small sprocket

N2 – speed of large sprocket

T1 – no of teeth in small sprocket

T2 – no of teeth in large sprocket

 Factor of safety : WB/W

where,

WB – breaking load

W – total load

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 CHAPTER V

CONCLUSION

Sprocket are used to transmit rotary motion between two shafts where gears are
unsuitable to perfom linear motion to a track. The sliding motion between chain
roller and sprocket tooth causes friction wear and wear occur in pin hole of chain
rollers making the chain to elongate and so that chain becomes slack. Chain
sprocket has problems like breaking of bushings and/or rollers, breaking of plates
and pins (unusual cracks), quickly wear of sprockets, Worn rollers,etc. Possible
causes of these problems are significant overload breakage, high impact pressure,
combination of worn chain with new sprockets, excessive chain wear far beyond
replacement level etc. Also there is a wear on sprocket tooth and outer surface.
Sprocket transmits engine power to wheel so without sprocket moving of rotary
motion between shaft would not be possible.
REFERENCE:

[1] Tushar S. Hingve, Y. A. Kharche and N.A. Kharche, “Diagnosis for the
Failure of Sprockets and Chain Drive”, In this study they found the faults by using
the various faults detection techniques and analyzed them. They tried to diagnose
the faults by using the simple techniques. They found out the major breakdowns
in mechanisms due to sprockets failure causing production losses to the company
and suggested counter measures by which these problem can be reduced.

[2] Sagar N. Vasoya, P. L. Koradiya and B. J. Patel, “Development of Sprocket

to Improvement the Torque for Off Road Bike”, In this paper, the process of
development in sprocket was studied and gear ratio between them was
investigated.

[3] Nikhil P. Ambole and Prof. P. R. Kale, “Design and Analysis of Carbon Fiber
Sprocket”, In this research, carbon fiber was introduced as a replacement for
conventional mild steel. They have done CAD through reverse engineering and
analysis was carried out using Hypermesh and ANSYS. Finite element analysis
was then carried out by using Mild Steel (IS 2062) and Carbon fiber.

[4] Parag Nikam and Rahul Tanpure, ”Design Optimization of Chain Sprocket
Using Finite Element Analysis”, In this research, the chain sprocket was designed
and analyzed using Finite Element Analysis for safety and reliability. ANSYS
software was used for static and fatigue analysis of sprocket design. Using these
results optimization of sprocket for weight reduction have been done. As sprocket
undergo vibration, modal analysis was also performed. The design of sprocket
has been successfully optimized with weight reduction of 15.67%. Also von-

18
mises stress of modified design was lesser than preliminary design with little
increase in deformation, which ultimately results in the safety and reliability of
design.

[5] Nikhil P. Ambole and Prof. P. R. Kale, “Finite Element Analysis Carbon Fiber
Sprocket using ANSYS”, In this paper, the stress of chain drive was studied and
the existing sprocket of Bajaj Pulsar 180 motorcycle was compared with the
sprocket of carbon fiber material. They have achieved this by using ANSYS 13,
by applying torque in to the model of sprocket

[6] Tushar S. Hingve and Dr. A. V. Vanalkar, “Faults Detection and Diagnosis of
the Sprockets Failure”, In this paper, the main objective was to find out the major
breakdowns in mechanisms due to sprockets failure causing production losses to
the company and to suggest counter measures by which these problems can be
reduced

[7] Yasir Afzal, Vandana Jha and Anil Mohapatra, “A Comparative Study Based
on ANSYS Analysis of Existing Sprocket’s Material with High Performance
Engineering 60 Abhishek Barua and Sasmita Kar Plastic Materials”, In this paper,
a comparative Study was done based on ANSYS analysis of existing sprocket’s
material with high performance engineering plastic materials.

[8] Kavit M. Shah and Prof. Dhruv U. Panchal, “Experimental Investigation on

Effect of Plasma Nitriding on Wear of Chain-Sprocket Assembly Used in
Motorcycle”, In this research, effect of plasma nitriding on wear of chain-

19
sprocket was studied. concluded that plasma nitrided sprocket has greater wear
resistance than the normal (untreated) sprocket.

[9] Swapnil Ghodake, Prashant Deshpande and Shrikant Phadatare,

“Optimization of Excavator Sprocket and its Validation by Test Rig Concept”, In
this research, the weight of excavator sprocket was optimized by reducing
material to get optimized design which could perform well under torque condition
keeping same constraints.

[10] Ebhota Williams S, Ademola Emmanuel and Oghenekaro Peter,

“Fundamentals of Sprocket Design and Reverse Engineering of Rear Sprocket of
a Yamaha CY80 Motorcycle”, In this paper the fundamentals of sprocket design

20