An

Mini Project Report

on

STUDY OF AUTOMATIC DISC BRAKING

Submitted to
JAWAHARLAL NEHRU TECHNOLOGY UNIVERSITY HYDERABAD

In partial fulfillment of the requirements for the award of the degree of

BACHELOR OF TECHNOLOGY

In

MECHANICAL

ENNGINEERING

By
KASTHURI ARUN KUMAR 18E31A0309
PATHI ABHINAV 18E31A0327
YEPURI PRASHANTH 18E31A0336
SHAIK MOHD ZAKIR SHAMIM 17E31A0350
MOHAMMED BARIQ 16H11A0348
Under the Guidance of
FAIZ ALI (Assistant Professor)

DEPARTMENT OF MECHANICAL ENGINEERING

MAHAVEERINSTITUTE OF SCIENCE AND TECHNOLOGY

VYASAPURI, BANDLAGUDA, HYDERABAD – 500005

2021 – 2022

i
 MAHAVEER INSTITUTE OF SCIENCE AND TECHNOLOGY

Vyasapuri, Bandlaguda, Keshavagiri Post, Hyderabad – 500005

DEPARTMENT OF MECHANICAL ENGINEERING

CERTIFICATE

This is to certify that the project work entitled “STUDY OF AUTOMATIC DISC

BRAKING” is submitted by K.ARUN, P.ABHINAV, Y.PRASHANTH ,SHAIK MOHD

ZAKIR SHAMIM, MOHAMMED BARIQ in partial fulfillment of the requirement for the
reward of Degree of B. Tech in MECHANICAL ENGINEERING from MAHAVEER

INSTITUTE OF SCIENCE AND TECHNOLOGY, during the academic year of 2021 – 2022.

The results embodied in this project report have not been submitted to any other University or
Institute for the award of any degree.

FAIZ ALI B. VENKATESHWAR REDDY

Assistant Professor Professor & Head of the Department
Project Guide

EXTERNAL EXAMINER DR. B. V. SANKER RAM

Principal

ii
GROUP CERTIFICATE

iii
 ACKNOWLEDGEMENT

This project work carried out as a part of our academic requirements for obtaining the B. Tech
degree was a wonderful experience. We take opportunity to thank all the people who motivated
and helped us to complete the project successfully. We would like to thank our guide FAIZ
ALI Assistant Professor, Department of Mechanical Engineering, for his valuable guidance
and support. We would like to express our sincere gratitude to our Head of the Department,
Professor B. VENKATESHWAR REDDY, Department of Mechanical Engineering and our
principal DR. B.V. SANKER RAM, Mahaveer Institute of Science and Technology for
granting us permission to carry out our project. We are also thankful to members of
Mechanical Engineering department.

We would also like to thank our parents, relatives and friends for their wholehearted support
and encouragement towards fulfillment of the degree.

1. KASTHURI ARUN KUMAR 18E31A0309

2. PATHI ABHINAV 18E31A0327
3. YEPURI PRASHANTH 18E31A0336
4. SHAIK MOHD ZAKIR SHAMIM 17E31A0350
5. MOHAMMED BARIQ 16H11A0348

iv
 DECLARATION

We hereby declare that the project report is done in “MAHAVEER INSTITUTE OF

SCIENCE AND TECHNOLOGY” under the guidance of FAIZ ALI Assistant Professor,
Department of Mechanical Engineering. The project is submitted in partial fulfillment of the
requirements for the award of the degree of B. Tech in MECHANICAL ENGINEERING.

This is a record of bonafide work carried out by us and the results embodied in this project
have not been reproduced or copied from any other source. The results embodied in this project
have not been submitted to any other university or institute for the award of any other degree.

1. KASTHURI ARUN KUMAR 18E31A0309

2. PATHI ABHINAV 18E31A0327
3. YEPURI PRASHANTH 18E31A0336
4. SHAIK MOHD ZAKIR SHAMIM 17E31A0350
5. MOHAMMED BARIQ 16H11A0348

v
 ABSTRACT

At the end of the 19th century the development of a brake system for the newly invented automobile
vehicles was needed. From that moment on, this equipment, which makes use of several components
(the brake disc among them), was developed. It was after the beginning of the Second World War, in
1938, that the brake system technological advance got great impulse due to the aeronautics industry
necessity. Historically, the first material used to make brake discs was the gray cast iron, which is a
material that fits the requirements it is intended for, such as: good thermal conductivity, good
corrosion strength, low noise, low weight, long durability, steady friction, low wear rate, and a good
price/benefit ratio. Therefore, for more than one hundred years, a great number of materials were
developed with this intention, but the most used until today is the cheap and easily produced gray cast
iron. Nowadays, a lot of emphasis has been given to the study of fatigue strength of gray cast iron
alloys through modeling to improve the service life of the component. Although this kind of analysis
presents meaningful results, experimental works are necessary to validate them, i.e., the component
must be studied under load conditions.

vi
LIST OF CONTENTS
CHAPTER Page No.

1. INTRODUCTION 1
HISTORY 2
RACING BREAKTHROUGH 3
MOTORCYCLE APPLICATIONS 4
MOTORCYCLES AND SCOOTERS 4
OTHER VEHICLES 5
RACING 7
CERAMIC COMPOSITES 8
ADJUSTMENT MECHANISM 9
DISC DAMAGE MODES 9
RUN-OUT 9
CRACKING 10
RUSTING 10
2. LITERATURE REVIEW 15
3. CATIA 19
OPTIONS USED IN CREATE SOLIDS 21
REFERENCE ELEMENTS 22
REFERENCE PLANES 22
REFERENCE LINES 23
REFERENCE POINTS 23
GENERATIVE DRAFTING 24
VIEWS 24
DIMENSIONING 24
BILL OF MATERIAL 25
CONCLUSIONS 26
REFERENCES 27

vii
 LIST OF FIGURES

Page.No.

Fig 1.0: On automobiles, disc brakes are often located within the wheel 2

Fig 1.1: A drilled motorcycle brake disc 2

Fig 1.2: Front automobile brake with rectangular open slots visible between the
disk's friction surfaces 4

Fig 1.3: Floating disc brake on Kawasaki W800 4

Fig 1.4: Radially-mounted brake caliper on a Triumph Speed Triple 5

Fig 1.5: A railroad bogie and disc brakes 6

Fig 1.6: Reinforced carbon brake disc on a Ferrari F430 Challenge race car 7

Fig 1.7: Mercedes Benz AMG carbon ceramic brake 8

Fig 1.8: Porsche Carrera S composite ceramic brake 8

Fig 1.9: GM disc brake caliper (twin-piston, floating) removed from its mounting for 11

Changing pads

Fig 1.10: Various types of brake calipers are also used on bicycle rim brakes. 12

Fig 1.11: Disk brake 13

Fig 1.12: Disc ring 14

Fig 2.1: Floating disc brake components 16

Fig 3.1: Different modules in CATIA 19

Fig 3.2: Sketch of the model 19

Fig 3.3: Disk brake 3 20

Fig 3.4: Design of Disk brake 21

viii
 CHAPTER 1
Introduction:

A disc brake is a type of brake that uses calipers to squeeze pairs of pads against
a disc in order to create friction that retards the rotation of a shaft, such as a vehicle axle,
either to reduce its rotational speed or to hold it stationary. The energy of motion is
converted into waste heat which must be dispersed. Hydraulic disc brakes are the most
commonly used form of brake for motor vehicles but the principles of a disc brake are
applicable to almost any rotating shaft.

Compared to drum brakes, disc brakes offer better stopping performance because the
disc is more readily cooled. As a consequence, discs are less prone to the brake
fade caused when brake components overheat. Disc brakes also recover more quickly
from immersion (wet brakes are less effective than dry ones).

Most drum brake designs have at least one leading shoe, which gives a servo-effect. By
contrast, a disc brake has no self-servo effect and its braking force is always proportional
to the pressure placed on the brake pad by the braking system via any brake servo,
braking pedal, or lever. This tends to give the driver better "feel" and helps to avoid
impending lockup. Drums are also prone to "bell mouthing" and trap worn lining
material within the assembly, both causes of various braking problems.

The brake disc (or rotor in American English) is usually made of cast iron, but may in
some cases be made of composites such as reinforced carbon–carbon or ceramic matrix
composites. This is connected to the wheel and/or the axle. To retard the wheel, friction
material in the form of brake pads, mounted on the brake calliper, is forced
mechanically, hydraulically, pneumatically,or electromagnetically against both sides of
the disc. Friction causes the disc and attached wheel to slow or stop.

1
 Figure 1.0 On Automobiles, disc brakes are often located within the wheel.

Figure 1.1 A Drilled Motorcycle Brake Disc

The development of disc-type brakes began in England in the 1890s, but they were not
practical or widely available for another 60 years. Successful application required
technological progress, which began to arrive in the 1950s, leading to a critical
demonstration of superiority at the Le Mans auto race in 1953. The Jaguar racing team
won, using disc brake equipped cars, with much of the credit being given to the brakes'
superior performance over rivals from firms like Ferrari, equipped with drum brakes.
Mass production quickly followed with the 1955.

1.2 History

Development of disc brakes began in England in the 1890s.The first calliper-type

automobile disc brake was patented by Frederick William Lanchester in his Birmingham
factory in 1902 and used successfully on Lanchester cars. However, the limited choice of
metals in this period meant that he had to use copper as the braking medium acting on
the disc. The poor state of the roads at this time, no more than dusty, rough tracks, meant
the copper wore quickly making the system impractical.

2
The American Crosley Hot Shot is often given credit for the first production disc brakes.
For six months in 1950, Crosley built a car with these brakes, then returned to drum
brakes. Lack of sufficient research caused reliability problems, such as sticking and
corrosion, especially in regions using salt on winter roads. Drum brake conversions for
Hot Shots were quite popular. The Crosley disc was a Goodyear development, a calliper
type with ventilated disc, originally designed for aircraft applications.

Chrysler developed a unique braking system, offered from 1949 to 1953. Instead of the
disc with calliper squeezing on it, this system used twin expanding discs that rubbed
against the inner surface of a cast-iron brake drum, which doubled as the brake
housing. The discs spread apart to create friction against the inner drum surface through
the action of standard wheel cylinders. Because of the expense, the brakes were only
standard on the Chrysler Crown and the Town and Country Newport in 1950 They were
optional, however, on other Chryslers, priced around $400, at a time when an entire
Crosley Hot Shot retailed for $935. This four-wheel disc brake system was built by Auto
Specialties Manufacturing Company (Ausco) of St. Joseph, Michigan, under patents of
inventor H.L. Lambert, and was first tested on a 1939 Plymouth. Chrysler discs were
"self-energizing," in that some of the braking energy itself contributed to the braking
effort. This was accomplished by small balls set into oval holes leading to the brake
surface. When the disc made initial contact with the friction surface, the balls would be
forced up the holes forcing the discs further apart and augmenting the braking energy.
This made for lighter braking pressure than with callipers, avoided brake fade, promoted
cooler running, and provided one-third more friction surface than standard Chrysler
twelve-inch drums. Today's owners consider the Ausco-Lambert very reliable and
powerful, but admit its grubbiness and sensitivity.

1.2.1 Racing breakthrough

Reliable calliper-type disc brakes first appeared in 1953 on the Jaguar C-Type racing car.
These brakes helped the company to win the 1953 24 Hours of Le Mans, developed in
the UK by Dunlop. That same year, the aluminium bodied Austin-Healey 100S, of which
50 were made, was the first car sold to the public to have disc brakes, fitted to all 4
wheels.

3
 1.2.3 Motorcycle Applications

The first motorcycles to use disc brakes were racing vehicles. MV Aguste was the first to
offer a front disc brake motorcycle to the public on a small scale in 1965, on their
relatively expensive 600 touring motorcycle, using a mechanical brake linkage. In 1969
Honda introduced the more affordable CB750, which had a single hydraulically-actuated
front disc brake (and a rear drum brake), and which sold in huge numbers. Disc brakes
are now common on motorcycles, mopeds and even mountain bikes

Figure 1.2 Front automobile brake with rectangular open slots visible between the
disk's friction surfaces

The brake disc is the component of a disc brake against which the brake pads are applied.
The material is typically grey iron, a form of cast iron. The design of the disc varies
somewhat. Some are simply solid, but others are hollowed out with fins or vanes joining
together the disc's two contact surfaces (usually included as part of a casting process).
The weight and power of the vehicle determines the need for ventilated discs The
"ventilated" disc design helps to dissipate the generated heat and is commonly used on
the more-heavily-loaded front discs.

• Motorcycles and scooters

Figure 1.3 Floating disc brake on Kawasaki W800

4
 Figure 1.4 Radially-mounted brake calliper on a Triumph Speed Triple

Lambretta introduced the first high-volume production use of a single, floating, front disc
brake, enclosed in a ventilated pressed-steel shroud and actuated by cable, during 1964
on their range-topping GT200 scooter. The 1969 Honda CB750 introduced hydraulic
disc brakes on a large scale to the wide motorcycle public, following the lesser known
1965 MV Agusta 600, which had cable-operated mechanical actuation unlike car disk
brakes that are buried within the wheel, bike disc brakes are in the airstream and have
optimum cooling. Although cast iron discs have a porous surface which give superior
braking performance, such discs rust in the rain and become unsightly. Accordingly,
motorcycle discs are usually stainless steel, drilled, slotted or wavy to disperse rain
water. Modern motorcycle discs tend to have a floating design whereby the disc "floats"
on bobbins and can move slightly, allowing better disc centering with a fixed caliper. A
floating disc also avoids disc warping and reduces heat transfer to the wheel hub.
Calipers have evolved from simple single-piston units to two-, four- and even six-piston
items. Compared to cars, motorcycles have a higher center of mass:wheelbase ratio, so
they experience more weight transfer when braking. Front brakes absorb most of the
braking forces, while the rear brake serves mainly to balance the motorcycle during
braking. Modern sport bikes typically have twin large front discs, with a much smaller
single rear disc. Bikes that are particularly fast or heavy may have vented discs.

1.2.4 Other vehicles

Disc brakes are increasingly used on very large and heavy road vehicles, where
previously large drum brakes were nearly universal. One reason is that the disc's lack of
self-assist makes brake force much more predictable, so peak brake force can be raised
without more risk of braking-induced steering or jack knife on articulated vehicles.
Another is disc brakes fade less when hot, and in a heavy vehicle air and rolling drag and
engine braking are small parts of total braking force, so brakes are used harder than on

5
lighter vehicles, and drum brake fade can occur in a single stop. For these reasons, a
heavy truck with disc brakes can stop in about 120% the distance of a passenger car, but
with drums stopping takes about 150% the distance. In Europe, stopping distance
regulations essentially require disc brakes for heavy vehicles. In the U.S., drums are
allowed and are typically preferred for their lower purchase price, despite higher total
lifetime cost and more frequent service intervals.

Figure 1.5 A railroad bogie and disc brakes

Still-larger discs are used for railroad cars and some airplanes. Passenger rail
cars and light rail vehicles often use disc brakes outboard of the wheels, which helps
ensure a free flow of cooling air. However, on some modern passenger rail cars, such as
the Amfleet II cars, inboard disc brakes are used. This reduces wear from debris, and also
provides protection from rain and snow, which would make the discs slippery, and
unreliable. However, there is still plenty of cooling for reliable operation. In contrast,
some airplanes have the brake mounted with very little cooling and the brake gets quite
hot in a stop, but this is acceptable as there is then time for cooling, and where the
maximum braking energy is very predictable.For automotive use, disc brake discs are
commonly manufactured out of a material called grey iron. The SAE maintains a
specification for the manufacture of grey iron for various applications. For normal car
and light-truck applications, SAE specification J431 G3000 (superseded to G10) dictates
the correct range of hardness, chemical composition, tensile strength, and other properties
necessary for the intended use. Some racing cars and airplanes use brakes with carbon
fiber discs and carbon fiber pads to reduce weight. Wear rates tend to be high, and
braking may be poor or grabby until the brake is hot.

6
 • Racing

Figure 1.6 Reinforced carbon brake disc on a Ferrari F430 Challenge race car

In racing and very-high-performance road cars, other disc materials have been
employed. Reinforced carbon discs and pads inspired by aircraft braking systems such as
those used on Concorde were introduced in Formula One by Brabham in conjunction
with Dunlop in 1976. Carbon–carbon braking is now used in most top-level motorsport
worldwide, reducing unspring weight, giving better frictional performance and improved
structural properties at high temperatures, compared to cast iron. Carbon brakes have
occasionally been applied to road cars, by the French Venturi sports car manufacturer in
the mid 1990’s for example, but need to reach a very high operating temperature before
becoming truly effective and so are not well suited to road use. The extreme heat
generated in these systems is easily visible during night racing, especially at shorter
tracks. It is not uncommon to be able to look at the cars, either live in person or on
television and see the brake discs glowing red during application.

7
 • Ceramic composites

Figure 1.7 Mercedes Benz AMG carbon ceramic brake Figure 1.8 Porsche
Carrera S composite ceramic brake

Ceramic discs are used in some high-performance cars and heavy vehicles. The first
development of the modern ceramic brake was made by British engineers working in the
railway industry for TGV applications in 1988. The objective was to reduce weight, the
number of brakes per axle, as well as provide stable friction from very high speeds and all
temperatures. The result was a carbon-fibre-reinforced ceramic process which is now used
in various forms for automotive, railway, and aircraft brake applications.

Due to the high heat tolerance and mechanical strength of ceramic composite discs, they
are often used on exotic vehicles where the cost is not prohibitive to the application. They
are also found in industrial applications where the ceramic disc's light weight and low-
maintenance properties justify the cost relative to alternatives. Composite brakes can
withstand temperatures that would make steel discs bendable.

Porsche's Composite Ceramic Brakes (PCCB) are siliconized carbon fiber, with very high
temperature capability, a 50% weight reduction over iron discs (therefore reducing the
unsprung weight of the vehicle), a significant reduction in dust generation, substantially
increased maintenance intervals, and enhanced durability in corrosive environments over
conventional iron discs. Found on some of their more expensive models, it is also an
optional brake for all street Porsches at added expense. It is generally recognized by the
bright yellow paintwork on the aluminum six-piston calipers that are matched with the
discs. The discs are internally vented much like cast-iron ones, and cross-drilled.

8
 • Adjustment mechanism

In automotive applications, the piston seal has a square cross section, also known as a
square-cut seal. As the piston moves in and out, the seal drags and stretches on the piston,
causing the seal to twist. The seal distorts approximately 1/10 of a millimeter. The piston
is allowed to move out freely, but the slight amount of drag caused by the seal stops the
piston from fully retracting to its previous position when the brakes are released, and so
takes up the slack caused by the wear of the brake pads, eliminating the need for return
springs. In some rear disc calipers, the parking brake activates a mechanism inside the
calliper that performs some of the same function.

• Disc damage modes

Discs are usually damaged in one of four ways: scarring, cracking, warping or excessive
rusting. Service shops will sometimes respond to any disc problem by changing out the
discs entirely, This is done mainly where the cost of a new disc may actually be lower
than the cost of labour to resurface the old disc. Mechanically this is unnecessary unless
the discs have reached manufacturer's minimum recommended thickness, which would
make it unsafe to use them, or vane rusting is severe (ventilated discs only). Most leading
vehicle manufacturers recommend brake disc skimming (US: turning) as a solution for
lateral run-out, vibration issues and brake noises. The machining process is performed in
a brake lathe, which removes a very thin layer off the disc surface to clean off minor
damage and restore uniform thickness. Machining the disc as necessary will maximise
the mileage out of the current discs on the vehicle.

• Run-out

Run-out is measured using a dial indicator on a fixed rigid base, with the tip
perpendicular to the brake disc's face. It is typically measured about 1⁄2 in (12.7 mm) from
the outside diameter of the disc. The disc is spun. The difference between minimum and
maximum value on the dial is called lateral run-out. Typical hub/disc assembly run-out
specifications for passenger vehicles are around 2⁄1000 in (0.0508 mm). Runout can be
caused either by deformation of the disc itself or by runout in the underlying wheel hub
face or by contamination between the disc surface and the underlying hub mounting
surface. Determining the root cause of the indicator displacement (lateral runout) requires
disassembly of the disc from the hub. Disc face runout due to hub face runout or

9
contamination will typically have a period of 1 minimum and 1 maximum per revolution
of the brake disc.

Discs can be machined to eliminate thickness variation and lateral run-out. Machining
can be done in situ (on-car) or off-car (bench lathe). Both methods will eliminate
thickness variation. Machining on-car with proper equipment can also eliminate lateral
run-out due to hub-face non-perpendicularity.

Incorrect fitting can distort (warp) discs; the disc's retaining bolts (or the wheel/lug nuts,
if the disc is simply sandwiched in place by the wheel, as on many cars) must be
tightened progressively and evenly. The use of air tools to fasten lug nuts can be bad
practice, unless a torque wrench is also used for final tightening.

• Cracking

Cracking is limited mostly to drilled discs, which may develop small cracks around edges
of holes drilled near the edge of the disc due to the disc's uneven rate of expansion in
severe duty environments. Manufacturers that use drilled discs as OEM typically do so
for two reasons: appearance, if they determine that the average owner of the vehicle
model will prefer the look while not overly stressing the hardware; or as a function of
reducing the unsprung weight of the brake assembly, with the engineering assumption
that enough brake disc mass remains to absorb racing temperatures and stresses. A brake
disc is a heat sink, but the loss of heat sink mass may be balanced by increased surface
area to radiate away heat. Small hairline cracks may appear in any cross drilled metal disc
as a normal wear mechanism, but in the severe case the disc will fail catastrophically. No
repair is possible for the cracks, and if cracking becomes severe, the disc must be
replaced. These cracks occur due to the phenomenon of low cycle fatigue as a result of
repeated hard braking.

• Rusting

The discs are commonly made from cast iron and a certain amount of surface rust is
normal. The disc contact area for the brake pads will be kept clean by regular use, but a
vehicle that is stored for an extended period can develop significant rust in the contact
area that may reduce braking power for a time until the rusted layer is worn off again.
Rusting can also lead to disc warping when brakes are re-activated after storage because

10
of differential heating between unrusted areas left covered by pads and rust around the
majority of the disc area surface. Over time, vented brake discs may develop severe rust
corrosion inside the ventilation slots, compromising the strength of the structure and
needing replacement Calipers

Figure 1.9 GM disc brake caliper (twin-piston, floating) removed from its
mounting for changing pads

The brake caliper is the assembly which houses the brake pads and pistons. The pistons
are usually made of plastic, aluminium orchrome-plated steel. Calipers are of two types,
floating or fixed. A fixed caliper does not move relative to the disc and is thus less
tolerant of disc imperfections. It uses one or more pairs of opposing pistons to clamp
from each side of the disc, and is more complex and expensive than a floating caliper.

A floating caliper (also called a "sliding caliper") moves with respect to the disc, along a
line parallel to the axis of rotation of the disc; a piston on one side of the disc pushes the
inner brake pad until it makes contact with the braking surface, then pulls the caliper
body with the outer brake pad so pressure is applied to both sides of the disc. Floating
caliper (single piston) designs are subject to sticking failure, caused by dirt or corrosion
entering at least one mounting mechanism and stopping its normal movement. This can
lead to the caliper's pads rubbing on the disc when the brake is not engaged or engaging it
at an angle. Sticking can result from infrequent vehicle use, failure of a seal or rubber
protection boot allowing debris entry, dry-out of the grease in the mounting mechanism
and subsequent moisture incursion leading to corrosion, or some combination of these
factors. Consequences may include reduced fuel efficiency, extreme heating of the disc or
excessive wear on the affected pad. A sticking front caliper may also cause steering
vibration.

Another type of floating caliper is a swinging caliper. Instead of a pair of horizontal bolts
that allow the caliper to move straight in and out respective to the car body, a swinging
caliper utilizes a single, vertical pivot bolt located somewhere behind the axle centerline.

11
When the driver presses the brakes, the brake piston pushes on the inside piston and
rotates the whole caliper inward, when viewed from the top. Because the swinging
caliper's piston angle changes relative to the disk, this design uses wedge-shaped pads
that are narrower in the rear on the outside and narrower on the front on the inside.

Figure 1.10 and Various types of brake calipers are also used on bicycle rim brakes.

The disc brake system is one important system to look at since it is not only used in
automotive industries but also in locomotives and in jumbo jets as well and hence
elaborating more on disc brake system, the main components of a disc brake are the
Brake disc or Rotor, Brake pads, Caliper. These parts are clearly shown in following

12
 Figure 1.11 Disk Brake

In this report I would be hoping to elaborate more about the brake disc (rotor) and how it
is manufactured, the materials used and its quality and defects compared to other brake
discs
Which are mad from deferent materials
The disc brake system is an assembly product and these parts are manufactured
separately through different procedures to one another. When the disc ring (brake disc) is
isolated, it has a perfect shape shown in below fig-1.12.

13
 Figure 1.12 Disc ring
In most vehicles these brake discs (disc ring) are made of cast iron, which has good
antiwear properties and it is cheap as well. But in certain other cases such as high
performance vehicles, these brake discs are not up to their standards of high performance
because the cast iron brake discs are heavy in weight and so reduces the vehicle's
performance to a particular extent. In case such as this, ceramic composite brake discs
are used, that are processed and used at high temperatures. These ceramic composite
brake discs are known to be heat resistant and able to withstand large compressive loads
at higher temperatures.
The details in which these ceramic composite brake discs (disc rings) are manufactured
are described in the following section of Manufacturing Details of Ceramic Composite
Brake discs.

14
 CHAPTER - 2

LITERATURE REVIEW

The most noteworthy security part of a car is its stopping mechanism, which should
moderate the vehicle rapidly and dependably under differing conditions. There are
numerous sorts of slowing mechanisms that have been utilized since the origin of the
engine auto, yet on a basic level they are for the most part comparative. The principle
capacity of slowing mechanism is to hinder the vehicle by changing the active vitality of
the vehicle into warm by rubbing, and this warmth must be successfully and productively
scattering to the surroundings by the brake parts.

The guideline of the circle brake was first licensed by Frederick Lanchester in his
Birmingham manufacturing plant in 1902, however was not well known until the point
that the awesome win by the Jaguar dashing autos in 1957 that their preferences were
obviously shown to the motoring open. Since the mid 1960s, plate stopping mechanisms
have turned out to be more typical frame in the most traveler vehicles, albeit a portion of
the traveler vehicles utilize drum brakes on the back wheels to hold expenses and weight
down and additionally to improve the arrangements for a stopping brake. Since the front
brakes perform a large portion of the braking exertion, this can be a sensible trade off.
The present examination is endeavored to contemplate screech clamor of the traveler
autos, along these lines circle brakes will be the focal point of this work.

There are joining types concerning disc brakes, fixed caliper then floating caliper. The
constant caliper commonly consists of two then extra pistons up to expectation practice
at once about both the interior or front pads. In system in accordance with make bigger
the arrest government twain pistons or extra may stay used. The pistons attempt in
conformity with end the rotating ring through exerting an even quantity on stress in
opposition to each facet about the rotor as like the every piston moves including even
pressure. The main hassle regarding the constant caliper is requiring a rotor position as is
not compatible along the geometric wants concerning the just modern front suspensions.

Nowadays, the floating caliper is often chronic about the dominance concerning
automobile arm systems. Typical ring brake factors are shown in aspect 2.1. It consists of
a rotor so is rigidly set up over the thill favor or consequently rotates with the
automobile’s ring through power axles, a floating caliper–piston meeting where the

15
piston slides inside the caliper, who is addicted in conformity with an anchor bracket
over the automobile break system, or a pair of arm pads. The caliper is free in imitation
of drift laterally on its grounding pins. When hydraulic block strain is applied, the piston
is pushed leading according to grasp the internal bed towards the disc then concurrently
the front doss is downtrodden via the caliper towards the disc. The hydraulic stress is
converting of an applied force to that amount presses the sack in opposition to the rotor.
This generates the friction forces wanted for the braking

Figure 2.1 Floating disc brake components

The handgrip clamor dynamometer has end up the most important testing tribune
because of identifying desire in accordance with cause clutter during braking. There are
pair designs because of the haft dynamometer. The first sketch is an inertia-type brake
dynamometer to that amount has flywheel addicted in imitation of it and perform be old
in imitation of dimension grumble at terrible pace tilt (Triches et al 2004, Chen 2005).
The second design is a drag-type handle dynamometer up to expectation perform only
take a look at arm grumble at a constant velocity (Dunlap et al 1999, Bergman et al 1999,
Cunefare then Graf 2002, James 2003, Fieldhouse et al 2004). Accelerometer yet double-
pulsed laser holographic interferometry are twain fine tools for determining the natural
frequencies, surge mode shapes and compelled response. However, the experiments are
commonly expensive and time consuming. Furthermore, the treatments located beyond

16
empirical education concerning some unique handgrip law may additionally not keep
applicable according to every other kind concerning brake structures.

Experimental modal evaluation is suitable in accordance with determine the brawny

homes over arm system. Traditional accelerometers bear been aged because conducting
modal analysis at alone factor and assembly ranges or measuring the troubled
frequencies at some stage in grumble occurrence. Tarter (1983) adequate sway
characteristics or answer intensity in the course of squeal era the usage of an
accelerometer and a microphone. He celebrated a number of checks about maze
including friction material, modified circle yet bed touch geometry. It was once
celebrated so properties regarding impingement material and sack counsel geometry hold
a large effect among decreasing grumble occurrence.

Matsui et al (1992) decent frequency responses of the brake assembly. Vibration modes
about the pad, circle yet caliper at some stage in grumble were identified via modal
analysis. In theirs experiments, the caliper, rotor yet chief sack vibrated within a united
behavior at a resonant frequency same in imitation of the squealing frequency. It was
once discovered so much confrontment vibrance is amplified then the system's associated
resonance dye is unstable, consequently government in imitation of complain generation.
They counseled as growing the hardness on the caliper yet optimising the geometry
regarding the doss pressure surface were brawny maze cures.

Ishihara et al (1996) utilized brake dynamometer to analyze screech age of the circle
brake gathering. In the wake of deciding the screech district, arbitrary swaying waves
were connected to the caliper by an electromagnetic shaker in the typical and
circumferential heading of the rotor. Accelerometers are settled on the caliper to quantify
the reaction while the rotor was pivoting on a brake dynamometer and weight was
connected. It was discovered that as the contact expanded the caliper had coupled
vibrations between the typical and in-plate course of the rotor. They likewise directed
hypothetical investigation in light of the exploratory outcomes. It was accounted for that
the caliper's corner to corner misshapening and the direct firmness of the coating material
greatly affected the age of screech (lining material was thought to be straight isotropic in
nature despite the fact that the rubbing material itself is a composite material.

Chen et al (2002) analyzed a few rotor outlines to set up the recurrence connection
between the in-plane and twisting methods of a rotor. They reasoned that coupling of

17
rotor extraneous in-plane modes and rotor bowing modes were the essential driver of
high recurrence brake screech. The screech recurrence would happen at the rotor in-plane
recurrence, however the mode shape would compare to the coupled out-of-plane mode.
Chen et al (2004) examined the connection between in-plane and out of-plane modes. A
key impact other than the rotor configuration was the brake cushion. They found that
contact powers have a tendency to energize the in-plane modes, and cushion twisting can
energize out-of-plane modes. Changing cushion thunderous frequencies through
chamfering can diminish high recurrence in-plane related clamor. They announced that
high recurrence screech features the significance of the brake rotor modes while low
recurrence screech has been found to depend all the more unequivocally on the caliper
parts notwithstanding the rotor.

Steel et al (2004) used twofold beat laser holography to examine both in-plane and out-
of-plane vibration of twin caliper plate brake at recurrence of 2.2 kHz. They isolated
dynamic pictures of the in-plane and out-of-plane vibration by specific method. It was
demonstrated that the circle modes are to a great degree mind boggling and assist sign is
the in-plane amplitudes are essentially bigger than out-of-plane vibration amplitudes.

Jaber et al (2006) demonstrated the operational redirection shape (ODS) contains both
rotor in-plane and out-of-plane modes. Modular investment examination with modular
confirmation basis (MAC) figuring between mode parts in free condition and framework
genuine modes appeared there is likewise a noteworthy commitment from caliper mode
in the perplexing mode, other than rotor distracting mode. Nonetheless, there is
additionally prove that when the rotor is altered to move its in-plane mode recurrence,
the screech recurrence is moved in like manner with the in-plane mode recurrence.

18
 CHAPTER 3

3.0 CATIA

These are different modules in CATIA using which different tasks can be performed. The
main window and modules of CATIA shown in figure:

Figure 3.1 Different modules in CATIA

Figure 3.2 Sketch of the model

19
Figure 3.3 Disk brake 3:

20
 Figure 3.4 Design of Disk Brake

3.1 OPTIONS USED TO CREATE SOLIDS

Pad - Pad is a method of defining three-dimensional geometry by projecting a two-

dimensional section at a specified distance normal to the sketching plane.

Pocket - Pocket is a method of extruding a profile or a surface and removing the

material resulting from the extrusion

Shaft - The Shaft tool creates a feature by revolving a sketched section around a centerline.

21
Fillet - A fillet is a curved face of a constant or variable radius that is tangent to, and that joins,
two surfaces. Together, these three surfaces form either an inside corner or an outside corner.

Chamfer - Chamfering consists in removing or adding a flat section from a selected

edge to create a beveled surface between the two original faces common to that edge.

Draft - Drafts are defined on molded parts to make them easier to remove from molds.

Thickness – Adds or removes to the faces.

Translation– Moving a body.

Mirror - Mirroring a body or a list of features consists in duplicating these elements

using symmetry by selecting a face or plane as reference.

Pattern - To duplicate the whole geometry of one or more features and to position this
geometry on a part.

3.2 REFERENCE ELEMENTS:

Reference elements are used as references for constructing the model. They are not
geometry features, but they aid in geometry construction by acting as references for
sketching a feature, orienting the model, assembles, components, and so on. Because of
their versatility references are frequently used.

1. Reference plane

2. Reference line

3. Reference points

3.2.1 REFERENCE PLANES:

Datum planes are used as reference to construct feature. Datum planes are considered
feature, but they are not considered model geometry. Datum planes can be created and
used as a sketch plane where no suitable exists.

22
Reference plane options used are: Thru plane, Offset plane, 9ffset coordinate system,
Blend section, thru axis, Thru Point/Vertex, Normal to axis, Tangent to cylinder, Angle
to the plane etc.

3.2.2 REFERENCE LINES:

Reference lines are used to create surfaces and other features, or as a sweep trajectories.
User sketch reference line in the same manner as any other features. Sketched curves can
consist of one or more sketched segment and of one or more open or closed loop.

Reference lines option used are: Sketch, Intersection surface, thru point, Form files,
Composite, Projected, Formed, Split, Offset from surface, from curve, from curve, from
boundary, Offset curve, Form equation etc.

3.2.3 REFERENCE POINTS: points are used to specify point loads for mesh
generation, attach datum targets and notes in drawings, and create coordinate systems
and pipe feature trajectories. User can also place axis, planes, holes and shafts at a point.

Point options used are: On surface, Offset surface, Curve coordinate surface, on vertex,
Offset coordinate system, three surfaces, at center, on curve, on surface, Offset point etc.

3.3 Model disc brakes:

23
3.4 GENERATIVE DRAFTING

Generative Drafting is a new generation product that provides users with powerful
functionalities to generate drawings from 3D parts and assembly definitions.

The Generative Drafting has been designed to show you how to generate drawings of varying
levels of complexity, as well as apply dimensions, annotations and dress-up elements to these
drawing.

Start – Mechanical Design – Drafting

3.4.1 Views

Front View - A front view is a projection view obtained by drawing perpendiculars from all
points on the edges of the part to the plane of projection. The plane of projection upon which
the front view is projected is called the frontal plane.

Projection View – Projection views are views conceived to be drawn or projected onto
planes known as projection planes. A transparent plane or pane of glass representing a
projection plane is located parallel to the front surfaces of the part.

Isometric View – The Isometric View command enables to create a 2D view with any
orientation, this orientation being the same as the one in the 3D viewer. Among other
results, and depending on how the 3D viewer is oriented when created the view, can
obtain a regular X-Y-Z isometric view.

3.4.2 Dimensioning

Generate Dimensions - To generate dimensions in one shot from the constraints of a

3D part. Only the following constraints can be generated: distance, length, angle, radius
and diameter.

Dimensions- To create and modify dimensions. These dimensions will be associative

to the elements created from a part or an assembly. When created, these elements are
associated with a view.

24
Generate Balloons – To generate balloons automatically to the components of an
assembly which are previously generated in assembly.

Text - To create a text, with possible line wrapping.

3.4.3 Bill of Material [BOM]

The Bill of Material, or parts list, corresponds to information on the product from which
the views were generated. It consists of an itemized list of the parts of a structure shown
on a drawing or on an assembly.

View of model:

25
 CONCLUSION

Disc brake is a complex system and understanding different issues related to its design and

operation require expertise from different disciplines e.g. tribology, material science, fluid

dynamics, vibrations etc. Disc brakes have evolved a lot over the decades due to

extensive research and development. There are still many phenomenon which are not

understood fully.

For realistic computational analysis of disc brake systems, it is crucial to further develop

on-linear finite element models which could simulate realistic evolution of contact

interface. Such models should be capable, atleast, to incorporate a realistic friction and

wear model, and temperature dependent material properties.

One of the issue which has attracted a lot of attention of research community is the brake

squeal. Due to continuous development of disc brake systems, they have become quieter

although squeal problem has not been solved well. The problem of predicting the brake

squeal propensity remains a challenging task for brake research community

26
 REFERENCES
1. P. Lingman. Integrated brake control downhill driving strategies. PhD thesis, Chalmers
Tekniska Hogskola, 2006.

2. C. Owen. Automotive Brake Systems, Classroom Manual. Today’s Technician. Delmar

Cengage Learning, 2010.

3. N. M. Kinkaid, O. M. O’Reilly, and P. Papadopoulos. Automotive disc brake squeal.

Journal of Sound and Vibration, 267(1):105–166, 2003.

4. H. Keller. Brake disc, particularly an internally ventilated brake disc, June 28 2011. US
Patent 7,967,115.

5. M. Franke. Brake disc, October 6 2009. US Patent Application 12/574,189.

6. A. Giorgetti. Disc for a disc brake for vehicles in general and for highperformance cars in
particular, November 28 2000. US Patent 6,152,270.

7. T. Deichmann and H. Lathwesen. Sheet cast disc-brake disc innovation through functional
integration. Proceedings of the Eurobrake, 16-18 April, Dresden, Germany, 2012.

8. S. Koetniyom. Thermal Stress Analysis of Automotive Disc Brakes. PhD thesis, University
of Leeds, 2000.

9. S. Koetniyom, P.C. Brooks, and D.C. Barton. The development of a material model for
cast iron that can be used for brake system analysis. Proceedings of the Institution of
Mechanical Engineers, Part D: Journal of Automobile Engineering, 216(5):349–362, 2002.

10. L. Wallis, E. Leonardi, B. Milton, and P. Joseph. Air flow and heat transfer in ventilated
disc brake rotors with diamond and tear-drop pillars. Numerical Heat Transfer; Part A:
Applications, 41(6-7):643–655, 2002.

27
28