MINI PROJECT REPORT

TITLE: DETAILED DESIGN AND

MANUFACTURE OF PISTON AND PISTON

RINGS.

TEAM MEMBERS:

S.NO. NAME ROLL NO.

1. S.V.ADITYA 10951A0303

2. N. BHANU CHANDER 10951A0304

3. M. NAVEEN 10951A0324

ABSTRACT

Project Title: DETAILED DESIGN AND MANUFACTURE

OF PISTON AND PISTON RINGS.

Project location: SAMKRG PISTONS & RINGS PVT.

LTD., Bonthapally, Hyderabad

OUTLINE: The subject of interest of the project lies at the depths

of an automobile. It is well known that an automobile is a machine

that converts chemical energy stored in the fuel into mechanical

energy required to move the vehicle. This entire operation is

performed by the engine of the automobile. The project deals with

the working part of the automobile engine i.e. The Piston.

PROCESS ANALYSIS: In the course of the project work, the stages

of the piston are observed and analyzed which include:

• Assessing the requirement of the manufacturer.

• Detailed designing of the piston.

• Cleaning and coating processes.

• Inspection processes.

• Packing and dispatching the final product.

CONCLUSION: The final analysis of this project work underlines

the understanding of the life of a piston i.e. from its initial design

blueprint to its final production, dispatching and the estimated

working life of the piston. Further, the project acts as a possible

source to understand and improve the quality of the piston

designing, resource management, and increasing the lifespan of the

piston.

INDEX

1. INTRODUCTION TO THE AUTOMOBILE AND THE PISTON

S.NO NAME PAGE NOS.

1.0. THE AUTOMOBILE 1

1.1. THE QUESTIONS ANSWERED - I 2

1.2. THE PISTON 4

1.3. THE QUESTIONS ANSWERED – II 5

1.4. THE PISTON RINGS 8

1.5. FACTS 9

2. THE LIFE CYCLE OF A PISTON AND PISTON RINGS

S.NO NAME PAGE NOS.

2.0. THE LIFE OF AN ENGINE AND ITS PISTONS 10

2.1. LIFE CYCLE OF A PISTON 11

2.2. LIFE CYCLE OF A PISTON RING 19

INDEX

3. DESIGN OF THE PISTON AND ITS PARTS

S.NO NAME PAGE NOS.

3.0. THE DESIGN – DEFINITION 21

3.1. PARTS OF A PISTON 22

3.2. DESIGN PROCEDURE 24

4. MANUFACTURE OF PISTONS

S.NO NAME PAGE NOS.

4.0. MANUFACTURE 34

4.1. PISTON MANUFACTURE 34

4.2. PISTON MANUFACTURE METHODS 35

4.3. ALLOY PREPARATION 36

4.4. DIE PREPARATION 38

4.5. DIE CASTING 39

4.6. PISTON SHOP MACHINING 40

INDEX

5. POST-MANUFACTURING PROCESSES ON PISTONS

S.NO NAME PAGE NOS.

5.0. POST-MANUFACTURING PROCESSES 43

5.1. THE QUESTIONS ANSWERED 44

5.2. CLEANING PROCESS 45

5.3. COATING PROCESS 47

5.4. INSPECTION PROCESS 48

5.5. STAMPING PROCESS 49

5.6. PACKING PROCESS 50

6. PISTON FAILURE ANALYSIS

S.NO NAME PAGE NOS.

6.0. WORKING LIFE OF A PISTON 51

6.1. HEAT SEIZURE 52

6.2. COLD SEIZURE 53

6.3. OIL FAILURE OR OIL FLASH 54

6.4. LUBRICATION CONFLICTS 55

6.5. PISTON DOME BREAKOUT 56

6.6. PISTON FRACTURE 57

INDEX

7. IMPROVEMENTS AND FUTURE PLANS

S.NO NAME PAGE NOS.

7.0. WHAT HAS BEEN UNDERSTOOD 59

7.1. IMPROVEMENTS 60

7.2. FUTURE PLANS 61

7.3. CONCLUSION 62

CHAPTER -1

INTRODUCTION TO THE AUTOMOBILE AND THE PISTON

1.0. THE AUTOMOBILE

Fig.1.1. The Automobile- An evolution and a revolution

1.1. THE QUESTIONS ANSWERED - I

• What is an automobile?

• Why is an automobile needed?

• When did this automobile emerge?

• How does an automobile work?

• Where exactly is the work carried out in the automobile?

1.1.1. WHAT IS IT?

An Automobile is a self propelled machine that has an engine, seating system,

a drive system and is used by the humans for various purposes.

1.1.2. WHY IS IT NEEDED?

It is used by humans for multiple purposes. Humans use it for transportation

purposes, carrying goods from one place to another, and in many parts of the

world, they are used for racing purposes as well. Basically it is an alternative

for travelling by foot as in the medieval ages. It saves both time and energy.

That is the reason of the never ending popularity of the automobile.

1.1.3. WHEN?

The history of the automobile begins as early as 1769, with the creation

of steam engine automobiles capable of human transport. In 1807, the first

cars powered by an internal combustion engine running on fuel gas appeared,

which led to the introduction of the ubiquitous modern gasoline- or petrol-

fuelled internal combustion engine in 1885. The year 1886 is regarded the year

of birth of the modern automobile - with the Benz Patent-Motorwagen, by

German inventor Karl Benz.

1.1.4. HOW DOES IT WORK?

Basically, an automobile is a machine that runs on fuel. Fuels such as petrol,

gasoline, and diesel that possess stored chemical energy internally, combust

inside the engine and result in a highly potent form of kinetic energy. This

kinetic energy is used to propel the parts of the engine connected to the axles

and the wheels. The motion transmitted to the wheels makes the automobile

move.

1.1.5. WHERE IS THIS WORK DONE?

The work in an automobile is done inside the engine. The engine consists of a

combustion chamber. The combustion chamber has an arrangement of a

number of cylinders. These cylinders in turn have pistons which are

responsible for the working process. The fuel, when injected into the

combustion chamber, mixes with compressed air and propels the piston up

and down. This piston is connected to a crankshaft which in turn is connected

to a drive shaft. This drive shaft provides motion to the axles and these axles

move the wheels.

Thus, as seen above, the automobile is a piece of art, invented by humans for

the betterment of their living and to ease the burden of their daily work.

In the next phase of this chapter, the demonstration of the automobile and its

functional parts are explained in detail.

1.2. THE PISTON

The automobile is a combination of various parts, merged together, in order to

provide the required output by the humans.

To understand the exact cycle of an I.C. engine and the parts of it, the diagram

of an Internal Combustion Engine is shown below.

Fig. 1.2. The parts of an Internal Combustion Engine

As seen in the diagram, the various parts of the I.C. Engine are shown in detail.

Out of these parts, the most critical parts are the Camshaft, the Connecting

Rod, the Crankshaft and the Piston.

The study project deals with the most important part of the I.C. Engine, i.e.,

THE PISTONS AND THE PISTON RINGS.

1.3. THE QUESTIONS ANSWERED - II

Fig.1.2. The Evolution of the piston

• What is a piston?

• When and Who invented it?

• Why is the piston used?

• Where is its location?

• How does it do the work?

1.3.1. WHAT IS IT?

A disc or short cylinder fitting closely within a tube in which it moves up and

down against a liquid or gas, used in an internal-combustion engine to derive

motion, or in a pump to impart motion.

Fig.1.3. The Piston and its main parts

1.3.2. WHEN AND WHO?

The piston was invented by a Scottish engineer James Watts in the 1700s. It

was initially created for use in the steam engines, but with the invention of

petrol engine by Gotlieb Daimler, the piston became popular for internal

combustion engines. Over 98% of all automobiles use the piston for power

transmission in the engines.

1.3.3. WHY USE IT?

The piston is the part, solely responsible for the compression of air, the

combustion of fuel and the exhaust of waste gases that are used for the

working of the I.C. Engine. Without the piston, an I.C. Engine is incomplete.

1.3.4. WHERE IS IT LOCATED?

The piston is located at the depths of an I.C. Engine. It is placed inside the

combustion chamber, sealed from the outside and is connected to the

crankshaft by means of a connecting rod.

1.3.5. HOW DOES IT ACCOMPLISH THE JOB?

The piston, situated in the combustion chamber, moves up and down due to

the intake and exhaust of air. It compresses the intake air and then, after the

fuel is injected, the air expands and moves the piston downwards. The

combusted air is then pushed out, again by the piston, and this is how the

piston performs the core process in an automobile. This motion of the piston

runs the crankshaft and helps in the running of the automobile.

Fig.1.4. Work cycle of an I.C. Engine Piston

1.4. THE PISTON RINGS

Fig.1.5. Piston rings

1.4.1. WHAT ARE THEY?

A piston ring is a split ring that fits into a groove on the outer diameter of

a piston in a reciprocating engine such as an internal combustion

engine or steam engine.

1.4.2. WHEN WERE THEY INVENTED?

The split piston ring was invented by John Ramsbottom who reported the

benefits to the Institution of Mechanical Engineers in 1854.

1.4.3. WHY ARE THEY USED?

There are three main functions of piston rings in reciprocating engines. They

are as follows:

• Sealing the combustion chamber so that there is no transfer of gases

from the combustion chamber to the crank.

• Supporting heat transfer from the piston to the cylinder wall.

• Regulating the engine oil consumption.

1.4.4. HOW MANY ARE USED?

Most automotive pistons have three rings:

• The top two while also controlling oil are primarily for compression

sealing (compression rings).

• The lower ring is for controlling the supply of oil to the liner which

lubricates the piston skirt and the compression rings (oil control rings).

• At least two piston rings are found on most piston and cylinder

combination.

1.4.5. ARE THEY USEFUL?

Yes. The piston rings are useful due to the following reasons:

• The use of piston rings dramatically reduces the frictional resistance.

• They reduce the leakage of steam in steam engines.

• They are responsible for the increase in power, efficiency and longer

maintenance intervals.

1.5. FACTS:

• The Piston is not "round". It is elliptical in shape

• The piston inside an I.C. Engine works at temperatures of up to 400° C.

• The pressures applied on the piston are of the range of 180 Bar.

• A piston goes up and down, up to 200 times per second.

• The gap in the piston ring compresses to a few thousandths of an inch

when inside the cylinder bore.

Thus, as we can see, pistons have a very rigid life. They work in extreme

conditions. The design and manufacture is done in order to make these pistons

very strong and durable.

Thus, this concludes the introduction part of the report. In the next chapter,

the life cycle of the piston, from its birth to death is explained thoroughly.

CHAPTER -2

THE LIFE CYCLE OF A PISTON AND PISTON RINGS

2.0. THE LIFE OF AN ENGINE AND ITS PISTONS

Every automobile is born from an idea. Every minute detail of an automobile is

thought about for many years and is then worked upon, to build the perfect

vehicle. Each vehicle has its own set of capabilities. Every person has a

different requirement. For example, the Indian Market is conscious about the

need for high mileage in cars. In other countries like for example, Japan, the

motoring enthusiasts crave for high-end power and huge amounts of torque in

the vehicles. Thus, their market produces high end sports cars. Also,

transportation vehicles such as trucks, buses and ships need high power

engines to carry heavy loads across long distances. Hence, engines of the

capacity of up to 15 Litres or 15,000 cc are used.

Thus, as we see, there are a large variety of requirements in the current

market. Now, the most crucial parts of an engine are the piston and the piston

rings. The piston makes or breaks the process of the engine and is directly

responsible for the effective working of the engine. Being such a crucial part,

the piston needs to be designed, manufactured and inspected carefully before

it is used in an engine. Without proper attention to the piston and piston rings,

the entire engine and the vehicle would be a complete failure. Thus, a very

strong focus must be placed on the life cycle of the piston and the piston

rings.

2.1. LIFE CYCLE OF A PISTON

• WHAT IS A LIFE CYCLE? :

The process in which an object’s life is determined from its birth to its

death is known as the life cycle of the object.

• DO PISTONS HAVE A LIFE CYCLE AS WELL? :

Yes, pistons do have a life cycle as well. It begins with an idea and then

ends up with the piston life coming to an end and eventually the

damaged piston being replaced with a new one.

The life cycle of a piston begins with an idea. The idea is based on the vehicle

requirements and the quality of the components required. The idea is the base

for the next step of the piston life cycle, i.e., the Piston Design.

2.1.1. DESIGN:

The design of the piston is an important aspect as it determines how the piston

should be manufactured. The design part helps the creators and

manufacturers realize the requirements. The design of the piston is useful to

understand the piston details and is the base for the manufacturing. The

pistons are designed in C.A.D and then solid modelling is done in C.A.T.I.A.

The stresses in the piston are simulated using ANSYS. After thorough testing of

the design, the piston is allowed to move further in its life, i.e., for

manufacture. (Refer Fig.2.1, Fig.2.2, and Fig.2.3.)

Fig.2.1. Design of piston using C.A.D.

Fig.2.2. Solid Modelling of a piston using C.A.T.I.A.

Fig.2.3. Piston design analysis using ANSYS

2.1.2. MANUFACTURE:

A piston design is realized at this stage of the piston life. This stage where the

design details are analyzed and understood by the manufacturers and the

piston enters the process of preparation is known as manufacture. It is stage

where the birth of the piston takes place.

Basically, piston manufacturing is done by three methods. They are as follows:

1. Casting,

2. Forging, and

3. Semi-Forging.

Casting:

Casting is the simplest and cheapest way to make a piston. To form a cast

piston, a proprietary mix of molten aluminium alloy is poured into a form.

Once it is cool, a mostly intact piston pops out of the mould. (Refer Fig.2.4.)

Advantages of casting process:

• Cast pistons are inexpensive to make.

• Alloy tuning of the fluid aluminium that is poured into the casting is

easy.

Disadvantages of casting process:

• If the alloy mixture is imperfect, the material can become hard and

brittle causing piston failure.

• A cast piston may crack and explode due to hot spots, partial seizures, or

too much clearance.

Machine Specifications:

• Machine size L x W x H (in mm) = 3000 x 1300 x 3200

• Die height distance = 250~630 (mm)

• Opening stroke = 320 mm

Fig.2.4. Casting machine

Forging:

Unlike a cast piston, which starts as molten aluminium, a forged piston is

shaped by slamming a slab of aluminium between two piston forms under the

influence of massive pressure. The piston is hammered into the required

shape. This process is called as the forging process. (Refer Fig.2.5.)

Advantages of forging process:

• The high pressure aligns the molecules, which results in a denser end

product.

• A forged piston dissipates heat better and can withstand greater

operating temperatures than a cast piston.

• A forged piston has double the lifespan of a cast piston.

Disadvantages of forging process:

• Forged pistons are more likely to cold seize.

• The forging process is more labour-intensive.

• Requires more machining to finish and is costlier.

Fig.2.5. Forging machine

Semi-Forging process:

Semi-forging is a process that casts the molten aluminium in a pressurized

environment, combining casting with the high pressure of forging and

produces a piston that has the weight, silicon content and controlled piston

swell of a cast piston with the strength of a forged part.

Advantages:

• Semi-forged pistons require less machining than a forged piston.

Thus, in these ways, pistons are manufactured after the design is assessed and

understood. The pistons are manufactured according to the requirement and

materials are used accordingly as well.

Once the piston is manufactured, it is checked for defects, errors and other

functional aspects. This step is called as Inspection.

2.1.3. INSPECTION:

The word inspection means to check a particular object for any irregularities

and defects that may have crippled into the product during either the design or

the manufacture stage.

In the life cycle of a piston, the inspection part is a very important aspect.

Without inspection, the piston cannot be deemed as fit to go out from the

factory. Defects due to improper manufacturing processes and material

handling can cause the piston to be damaged. Thus, inspection is performed to

see if there are any irregularities in the patterns or if the piston is not up to the

mark as per design standards. Any piston found with defects is rejected and is

sent to scrap.

The various processes in the inspection of a piston are as follows:

1. Bore Grading,

2. Outer Diameter i.e. O.D. Checking, and

3. Stamping.

In these processes, all the minute details of the manufactured piston are

analyzed and defects are rectified if doable. The process is extremely rigid up

to the point where a stamp in the wrong direction can cause the piston to be

rejected.

The inspection process complete, the pistons are packed and sent to the

customer. The packaging process involves the following operations:

1. Ring Assembly,

2. Circlip Assembly,

3. Gudgeon Pin Assembly, and

4. Paper Packing.

The piston is used in various conditions and can survive up to 1,50,000 KMS.

After this, the piston gets damaged beyond repair and eventually, the

damaged piston is replaced.

Thus, all these process performed in the order, without any deviations,

contribute to the life cycle of a piston.

The same process as above is depicted through a flow chart. (Refer Fig.2.6.)

Initial Design and Analysis

Receive /Inspection of raw materials

Alloy preparation

Foundry

Runner and raiser cutting

Heat treatment casting

Machining

Ultrasonic cleaning

Dimensional inspection

Visual inspection. Fig.2.6. Flow Chart

Dispatch

Thus, this completes the life cycle of the piston.

2.2. LIFE CYCLE OF A PISTON RING

Piston rings are one of the most important parts of I.C. engines. They are open-

ended rings that fit into a groove on the outer diameter of a piston. The

principal function of the piston rings is to form a seal between the combustion

chamber and the crankcase of the engine. The aim of using piston rings is to

prevent combustion gases from passing into the crankcase and oil from passing

into the combustion chamber.

The three main functions of piston rings in reciprocating engines are:

• Sealing the combustion/expansion chamber.

• Supporting heat transfer from the piston to the cylinder wall.

• Regulating engine oil consumption.

2.2.1. MANUFACTURE

Piston rings are generally made up of cast iron. The blanks of cast rings of

required size and desired properties are procured from the local foundries.

After that, the blanks are cleaned and get ground. Then the blanks undergo

through various processes like facing, rough diameter, rough boring, finish

diameter & finish boring.

The rings are generally machined to the required shape by means of turning, a

process in which the ring blank, already axially ground, is copy turned on the

inside and outside diameters. After a segment equivalent to the free gap is cut

from the ring it assumes the free shape that gives it the required radial

pressure distribution when fitted into the cylinder.

2.2.2. COATING PROCESS

After the completion of machining process, the following surface treatments

for piston rings are carried out. The coating processes are done in order to:

• Principally designed to provide corrosion protection for storage.

• Enhance the appearance, and,

• Improve the running of the piston rings.

The following coating processes are performed on the piston rings:

• Bronze Coating

• Ceramic Chrome Plating

• Chrome Plating

• Copper Plating

• Molybdenum Coating

• Phosphate Coating

• Plasma Sprayed Coating , and,

• Tin Coating.

After all these processes are carried out, the piston rings are fixed onto the

piston outer diameter and are sent for inspection.

Thus, this completes the life cycle of the piston ring.

With these aspects thoroughly explained, the life cycle of the piston and the

piston rings are fully understood. The next chapter deals with the design part

of the piston and its rings.

CHAPTER-3

DESIGN OF THE PISTON AND ITS PARTS

3.0. THE DESIGN - DEFINITION

What is design?

The process by which a product is analyzed, thought up and is dimensionally

assessed by various engineers is called as design. Also, design relates to the

development of the various parts of a product through drawings, solid

modelling and by analysis of the various stresses that exist in the parts to

approve the final outcome.

In the design of the piston, the various softwares that are used are C.A.D.,

C.A.T.I.A. , ANSYS , PRO – E , and NASTRAN (Aircraft engine purposes). The

piston design consists of the design of six different parts that are designed

individually and are merged together to form the final piston design. The

various parts of piston designing are as follows:

1. Design of Piston Head i.e., The Crown,

2. Design of Radial Ribs,

3. Design of Piston Rings,

4. Design of Piston Barrel,

5. Design of Piston Skirt, and,

6. Design of Piston Pin i.e., Gudgeon Pin.

Each of the parts and its design are explained in detail in the manner of a

linear, step by step procedure in the next phase of the chapter.

3.1. PARTS OF A PISTON

There are six parts of a piston as seen in the previous section of the chapter.

Each of these parts are designed individually and are assembled with each

other to form the final design structure.

The various parts are defined as the sub-topics of this topic in the chapter

(Refer Fig. 3.1.).

Fig.3.1. Parts of a Piston

3.1.1. THE CROWN

The upper part of piston is called as Crown. The primary function of the crown

is to transmit the power which is developed due to combustion of fuels.

It helps the piston in converting the energy developed due to combustion into

linear motion of piston then linear motion of piston is converted in to

rotational motion with help of connecting rod.

The connecting rod is also connected to fly wheel too so fly wheel is energy

absorbing wheel which in turn is connected to piston so it helps in compression

of piston. The crown is usually thick in order to with stand the high pressure

developed inside the cylinder.

If there is no crown, then there would not be any compression and the piston

would never work.

3.1.2. PISTON RINGS

A piston ring is a split ring that fits into a groove on the outer diameter of

a piston in a reciprocating engine such as an internal combustion

engine or steam engine.

3.1.3. PISTON BARREL

The side wall part of a piston, which forms its working surface in distinction to

the head portion, is called as the piston barrel. The barrel is usually made very

slightly less in diameter near the head end than at the crank end, to allow for

the greater expansion of the former in service.

The central portion of the barrel is made very slightly less in diameter than

either end portion so as to confine the bearing to the end portions.

3.1.4. PISTON SKIRT

The piston skirt is the part that is below the piston rings and bosses. The

function of the piston skirt is to act as a bearing for side thrust i.e., normal

reaction between the piston and cylinder walls

3.1.5. GUDGEON PIN

The Gudgeon Pin connects the piston to the connecting rod and provides a

bearing for the connecting rod to pivot upon as the piston moves. In very early

engine designs, the gudgeon pin was located in a sliding crosshead that

connects to the piston via a rod. A gudgeon is a pivot or journal.

Table 3.1. Table showing the various dimensional attributes

Thus, these are the various parts of the piston that are designed in order to

produce the complete piston design. The design of all these parts is discussed

in detail in the next phase of this chapter.

3.2. DESIGN PROCEDURE

The piston is designed in an order of six part designs. These designs involve a

series of six steps in which various formulae are used to determine the stresses

and loads acting on each individual part.

The various steps are mentioned and discussed in detail as following:

3.2.1 DESIGN OF THE CROWN

The design of the crown is determined on the basis of strength as well as on

the basis of heat dissipation. The larger of the two values is adopted. The steps

involved are:

[ i ] Thickness of crown based on strength:

�� =������� (in mm.)

Where, P = Maximum Gas Pressure in � ����

D = Cylinder Bore in mm.

�� = Permissible Tensile stress of piston material in � ����

[ ii ] Thickness of crown based on Heat Dissipation:

�� = �

.��� (�����) (in mm.)

Where,

H = Heat flowing through crown in Watts

k = Heat conductivity factor in � ��

° !

"# = Temp. at centre of crown in °

"$ = Temp. at edges of the crown in °

Also,

H= C x H.C.V. x m x B.P.

Where, C = Constant of value 0.05

H.C.V. = Higher Calorific Value of fuel in +, +-�

m = Mass of fuel used in

+, +�� ./0!

B.P. = Brake Power in KW

3.2.2. DESIGN OF RADIAL RIBS

Radial ribs are used at up to four in quantity. The thickness of the rib varies

from

�1 = �� �

Where, �� = Selected Thickness of crown

3.2.3. DESIGN OF PISTON RINGS

Radial Thickness of Piston rings,

� = ����2�� (in mm.)

Where,

D = Cylinder Bore in mm.

�2 = Pressure of gas on cylinder wall in � ����

�� = Allowable Tensile stress in � ����

Axial Thickness of piston rings is taken as,

� = 3. 4� �5 � (in mm.)

Minimum axial thickness of piston ring is given by,

� = �367 (in mm.)

Where,

67 = Number of Piston rings.

Width of top lands,

8 = �� �5 . ��

Width of other ring lands,

8 = 3. 4�� �5 �

Gap between free ends of the ring,

9 = �. �� �5 :�

Gap when ring inside cylinder,

9 = 3. 33� �5 3. 33:

3.2.4. DESIGN OF PISTON BARREL

Radial depth of piston ring grooves,

b = � + 3. :==

Where,

�= Radial thickness of piston rings.

Maximum thickness of the barrel,

�� = 3. 3�� + 8 + 4.5 mm

Where,

b = Radial depth of piston grooves

Piston wall thickness towards open end,

�: = 3. ��� to 0.35 �� 3.2.5. DESIGN OF PISTON SKIRT

Let, L = Total length of piston in mm.

Maximum side thrust due to gas pressure P,

R = µ x F� : x P ..............................(1)

Where,

µ = 0.1,

D = Cylinder bore in mm

P = Maximum gas pressure

The side thrust due to bearing pressure is given by.

R = �8 x D x l ..............................(2) Where,

l = Length of skirt in mm.

From (1) and (2), length of skirt is determined.

Total length of piston is given by,

L = Length of Skirt + Length of ring section + Top Land

3.2.6. DESIGN OF GUDGEON PIN

Load on the pin due to bearing pressure,

Load due to bearing pressure = �8 x S3 x T ............................. (3) Where,

S3 = Outside diameter of the pin in mm.

T = Length of pin in the bush of small end of connecting rod in mm.

�8= Bearing Pressure at the bushing

Maximum load on the piston due to gas pressure,

Max. Load due to gas pressure = F� : x P ............................. (4)

Equating (3) and (4), the outer diameter of the piston S3 is obtained.

Inside diameter of the pin,

SV = 0.6 x S3

Maximum bending moment at the centre of the pin,

M = �.�X ............................. (5)

Also, Maximum bending moment M,

M = F � YS3:� SV:

S3 Z �8 ............................. (6) Equating (5) and (6), the value of �8 is found out.

Where, �8 = Allowable or permissible bending stress

�8 = 140 � ���� for heat treated alloy steel.

The diagram shows the various dimensional aspects used in piston designing

(Refer Fig.3.2.)

Fig.3.2. Dimensional representation of piston design

Thus, this completes the design of the piston. The final piston is designed using

softwares and is processed as a blueprint for the next stage of its life i.e., The

Manufacture.

CHAPTER - 4

MANUFACTURE OF PISTONS

4.0. MANUFACTURE

What is manufacture?

Manufacture is the word that, in engineering practices, is used to describe the

process of making or preparing a product on a very large scale, using materials,

human power and machinery.

Manufacturing a product is the primarily necessary due to the fact that the

consumer needs the product for his day to day uses. Anything from small and

tiny razor blades to the large scale products like aircraft turbine blades are

required by humans for their daily based work. Thus, in order to deliver the

customer’s desire, products are manufactured, according to the user demand,

in small and large scales and are supplied to the user.

4.1. PISTON MANUFACTURE

Pistons and piston rings are the most worked upon and the most important

parts of an I.C. Engine. Without these parts, an I.C. Engine cannot function and

the automobile, as we know today, would have never come into existence.

Thus, as studied in the earlier chapters, the requirement of a piston is very

radical to Automobile Engineering. Consequently, the requirement is the

prime reason for the Manufacture of the I.C. Engine Piston and Piston Rings.

The various manufacturing aspects of pistons and piston rings are explained

elaborately in the next phase of this chapter.

4.2. PISTON MANUFACTURE METHODS

Basically every component manufactured goes through a certain process. The

process is strict, rigid and highly detailed in attributes. The same applies to the

manufacture of pistons.

Every piston manufactured is done by any one of the following three

processes. The processes are as follows:

1. Casting,

2. Forging, and,

3. Semi- Forging.

The study project performed at SAMKRG Pistons & Rings Pvt. Ltd., focuses

primarily on the manufacture of pistons by means of Casting Processes. All the

pistons prepared at the plant are done so by casting methods. The

understanding of the initiation of manufacture, the casting process and the

piston production techniques are discussed in this chapter.

Each piston that enters and exits the manufacturing process undergoes the

following stages. The stages are as follows:

• Alloy Preparation

• Die Preparation

• Die Casting, and,

• Piston Shop Machining.

These individual stages and their sub-stages are discussed in detail in each of

the sub-topics of this chapter.

4.3. ALLOY PREPARATION

The phase of manufacture where in the metal required for the piston

production is produced is known as metal preparation process. This phase is

independent of all the other phases of the manufacturing process. Also, it is

the primary step of making a piston and all the other processes are dependent

on the material preparation process.

The basic materials used in the metal preparation are as follows:

• Cast Iron

• Aluminium

• Silicon

• Copper

• Nickel

• Manganese

• Magnesium,and,

• Titanium.

Based on the requirement of the customer, three or more of the metals

mentioned above are combined to form an alloy of variable strength and

different weight characteristics.

The various alloys used in the automotive industry pistons are represented in

the form of a table. The temperatures indicated are the furnace temps. (Refer

Table 4.1.)

S.no Alloy components Silicon % Additives Alloy temp. Usage

1. Si, Cu, Ni 9 None 650°C Less

2. Si, Cu, Ni 11 None 680°C Less

3. Si, Cu, Ni 13 Mg (minor) 750°C-770°C Most used

4. Si, Cu, Ni 13 High Cu 750°C-770°C TVS Bikes

5. Si, Cu, Ni 20 None 790°±10°C Moderate

6. Si, Cu, Ni 23 None 790°±10°C Moderate

7. Si, Cu, Ni 25 Mn or Ti 790°±10°C TVS 2-Stroke

Table 4.1. Materials used in Piston Manufacture

The alloy is prepared by first heating the solid state aluminium in a furnace. A

furnace is a place where the metal in solid state is heated at temperatures

exceeding 600°C in order to convert the solid metal into molten state. This

process is done in order to cast the molten metal into the required shape as

the molten metal easily takes any shape given.

Basically furnaces used in the process are of two types. They are shown as

below.

FURNACES

INDUCTION TYPE BULK MELTER TYPE

1. CAPACITY = 300 KGS. 1. TYPE BC 401. CAPACITY = 250 KGS.

2. CAPACITY = 500 KGS. 2. TYPE BC 171. CAPACITY = 150 KGS.

In the factory, the majorly used furnace is the induction type furnace, this

being due to the high capacity of up to 500 KGS. (Refer Fig 4.1.)

Fig. 4.1. Induction Furnace

Induction Furnace specifications:

• Power Source: 240V A.C., 40 KW Electrical input.

• Capacity: 500 KG per hour melting.

• Working Frequency: 1000 Hz.

Thus, the aluminium is heated according to the requirement and then

processed forward to the next stage of manufacturing i.e., into the Die Casting.

4.4. DIE PREPARATION

The die is the part or the tool mechanism which is used to cast the molten

metal into the shape of the piston. The die is basically a piece of hard die steel

that is shaped into the casting shape in order to pour the molten metal. The

die is the tool which helps in the formation of the product into its shape and

allows it to cool down and solidify into the required shape.

Pistons are cast in gravity dies using a gravity die casting machine. The die is

made up of the following parts:

1. Core,

2. Guide rings,

3. Die Body, and,

4. Crown or Top Risers.

The Core of the die consists of the following parts:

1. Centre tool - 1 Piece,

2. Side tools - 2 Pieces,

3. Boss Tools -2 Pieces.

The materials used are as follows:

1. Core: HDS i.e., Hot Die Steel.

2. Guide Plates: H11 grade, H13 grade.

To remove the porosity inside the die, clay is used.

The die has a life of 50,000 castings effectively.

The testing of the die quality is done by D.M.I.R or Die Manufacture &

Inspection Report Process.

Thus, the die preparation for the casting process is complete. The next step

involves casting the molten metal into the prepared die and the process is

known as Die Casting.

4.5. DIE CASTING

• Casting is a manufacturing process by which a molten material such as

metal or plastic is introduced into a mould, allowed to solidify within the

mould, and then ejected or broken out to make a fabricated part.

• Casting is used for making parts of complex shape that would be difficult

or uneconomical to make by other methods, such as cutting from solid

material.

• Die Casting, also known as Permanent Mould Casting, is a process in

which the molten material is forced into a steel mould or die casting die.

• This process is usually accomplished by using high pressure. Permanent

moulding is another form of gravity casting using an iron mould.

• Gravity Die Casting uses the force of gravity, instead of high pressure

means, to fill a permanent mould, or die, with molten material.

The cast piston is removed and is sent for heat treatment where in the piston

is rapidly heated and cooled to reinforce its strength and hardness. The first

phase of heat treatment is called the Quench Phase. In this phase the alloy

piston is heated to 920°F causing the copper in the alloy to become dissolved

in the aluminium and forming what is called a "Single Phase Alloy". If allowed

to air cool naturally, the copper will tend to reconstitute, or reform itself

within the alloy. However, when the heated alloy is cooled rapidly by water

quenching the reformation of the copper is retarded and the aluminium,

supersaturated with copper, is locked into the "Single Phase Alloy" state.

Thus, the die casting of the piston is done using a Gravity Die Casting machine

and the piston is removed after solidifying completely. This solidified piston is

then sent into the Piston Shop for further machining process.

4.6. PISTON SHOP MACHINING

Fig 4.2. Piston Shop

The Piston shop (Refer Fig 4.2.) is the place in the factory where in the

machining is done on the piston. The solid shaped piston is taken and is

machined accordingly to produce the various dimensional attributes required.

Every operation is performed by Computerized Numerical Control Machines or

C.N.C. Machines

The various processes performed in the piston shop are as follows:

1. C.N.C. O.E.B. i.e., Open End Bore:

This process of machining is done in order to achieve the chamfer required, to

machine the centre drill and to produce the open end bore of the piston.

2. C.N.C. O.D. i.e., Outer Diameter Cutter:

This process is performed in order to cut the Outer Diameter on the piston

which is the place where the piston rings are inserted.

3. C.N.C. O.H.D i.e., Oil Hole Drilling and C.H.D i.e., Cross Hole Drilling:

The Oil Holes are drilled with a drill bit of 1.2 mm by the oil hole drilling

machine. The cross holes are drilled with a drill bit of 1.5mm by the cross hole

drilling machine. The Oil Holes and the Cross holes are required in order to

allow and regulate the oil entering the piston for lubrication.

4. C.N.C. R.GR. i.e., Ring Grooving:

The ring grooving process is performed by placing the piston into a machine

with a rotating tool having groove creators. This mechanism acts on the placed

piston and creates the ring grooves on the piston.

5. C.N.C. 4TH Station:

The machine gets its name from the fact that there are four working positions

on the table of this machine. At the initial point, the user places the piston

onto the holder. The table rotates and at the second position, rough boring is

performed for the Gudgeon Pin. At the third station on the table, Circlip

groove is bored into the piston. Finally, at the fourth station, Fine boring is

performed. This machine needs to be changed for every 10,000 pistons.

6. C.N.C. F.O.D. i.e., Fine Outer Diameter:

The smoothening and fineness of the outer diameter is performed here. Also,

the centre drill is cut out on this machine.

After these machining processes are performed, the de-bearing, washing,

Carbon coating and Moly-coating processes are performed in order to make

the piston more durable and friction resistant. The Carbon coating provides

strength and the Moly-Coating is an anti friction coating. Also, these processes

add shine and appeal to the piston.

Thus, with these processes complete, the manufacturing part of the piston is

complete. The exhaustive methods present in the manufacturing process have

been studied and understood.

The next chapter deals with the final aspects of the piston factory life i.e.,

Cleaning, Inspection and Packaging processes.

CHAPTER-5

POST- MANUFACTURING PROCESSES ON PISTONS

5.0. POST-MANUFACTURING PROCESSES

In the previous chapter, the manufacturing aspects of the piston have been

dealt with. Now, this chapter deals with the understanding of the post-

manufacturing processes that are performed on the piston. Effectively, this

chapter deals with the various jobs that are conducted on the piston after its

manufacture is complete. The processes involved are as follows:

1. Cleaning,

2. Coating,

3. Inspection,

4. Stamping, and,

5. Packaging.

These aspects of post-manufacturing processes are explained in detail in the

further phases of this chapter.

These processes are the final stages of the piston’s factory life. After the

completion of these steps, the piston is dispatched back to the customer.

5.1. THE QUESTIONS ANSWERED

Now, the questions that arise in the mind are that

• Why are these post-manufacturing processes required?

• How do they affect the piston life?

5.1.1. WHY ARE THEY USED?

The post-manufacture processes are used in order to bring out the best out a

piston. The cleaning processes are used in order to remove any impurities

present in or on the piston. The coating processes reinforce the piston’s

external strength and enhance the overall appeal. The inspection processes are

performed to check for any discrepancies in the piston manufacture. Without

the help of these post-manufacturing processes, a piston would be a raw,

machined piece of metal with impurities and irregularities.

5.1.2. HOW DO THEY AFFECT THE PISTON LIFE?

The cleaning process involves a series of cleaning techniques that are roughed

on the piston. These processes possess different technical abilities, that when

performed on the piston, help in both cleaning and strengthening of the piston

and its various intricate parts. The coating processes help in providing a solid

coat of strength and polish on the piston. The inspection helps in removing any

missed defects in the piston. The effect of these processes is so high that it

drastically improves the Piston life, by almost a grand margin of up to 10,000

KMS.

With these questions answered, the necessity of the post-manufacturing

processes and its magnitude of importance has been understood. In the next

phases of the chapter, these processes are explained in detail in an orderly

fashion.

5.2. CLEANING PROCESS

Cleaning is defined as the process of removing impurities, dust, and other

foreign materials present in or on an object by various methods. Cleaning is

necessary in order to make objects free from the problems caused due to

various impurities.

In the post-manufacturing process of the piston, the cleaning process plays a

very vital role in eliminating the various impurities that are left over by the

manufacturing process. The various cleaning processes ensure that the piston

and piston rings come out clean after the process.

The different stages of the cleaning process are performed on a 12 station

cleaning machine (Refer Fig 5.1.). The various stages are as follows:

Fig.5.1. Piston Cleaning Machine

• Piston placing

• Degreasing (2 nos.): To remove grease deposited on pistons after

manufacture and production

• Running Water Cleaning (2 nos.): To clean the degreasing elements.

• Acid Cleaning with Phosphoric Acid (1 no.): Used to remove carbon

deposits from the pistons.

• Running Water Cleaning (1 no.): Used to remove the phosphoric acid

that remains after Acid cleaning.

• DM Water Cleaning (1 no.): Used to remove any other impurities left

over.

• Sodium Stannate Cleaning (2 nos.): Used for plating purposes.

• Running Water Cleaning (2 nos.): Used to remove any sodium stannate

remaining.

• Hot DM Water Cleaning (1 no.): High temperature DM water is used for

approximately 60-75 seconds in order to remove any final impurities.

Thus, this completes the piston cleaning process. The piston is now sent for

Coating Process.

5.3. COATING PROCESS

Coating on the piston is provided in order to make it resistant to rust, to

reduce friction and to improve the overall look and strength of the piston.

Moly-coating, Graphite Moly-Disulphide coating, Ceramic-Metallic coating

are the various coatings used on pistons.

The coating is done in two stages. They are as follows:

1. Stage 1: Initial coating is done at a temperature of 60°C. The Molybdenum is

coated at this temperature and is allowed to settle down on the surface.

2. Stage 2: In this stage, the second process of coating is done by heating the

coated piston to 180°C. At this temperature, the Molybdenum heats up and

firmly sticks to the surface to form a solid coat.

5.3.1. USES

• Moly-Coating is an anti-friction coating.

• It is used to provide better lubrication to the piston when working.

• Coating makes the pistons resistant to scuff damage.

• Ceramic coatings produce a “Thermal Barrier” on the piston and protect

it from damages due to heat.

Thus, the coating process is complete. The piston is sent for inspection process.

5.4. INSPECTION PROCESS

Inspection of the piston is done in order to prevent any discrepancies from

slipping into the final product. Any errors in the piston after manufacturing are

rectified and the non-rectifiable pistons are rejected and sent back as scrap.

The various processes that are involved in the inspection process are as

follows:

• Bore Grading: This process involves the grading of the piston by its

design and manufacturing type. It consists of two types of piston grading

and they are as follows:

[i] Paint Models: The paint model bore grading is classified as Black

paint bore grading and white paint bore grading. E.g.: Royal Enfield

Piston bore grading.

[ii] Normal Models: Normal grading procedure is performed on these

pistons.

A dimension of 2.5 Microns is considered as a grade in the bore grading

system.

• O.D. i.e., Outer Diameter Checking: The Outer diameter of the piston is

checked for any errors. A dimension of 10 Microns is used as one grade.

A grading system of three grades is used. They are as follows:

[i] Grade ‘A’: 0 to -10.

[ii] Grade ‘B’: 11.5 micron in Height ± 8 micron for final product.

[iii] Grade ‘C’

5.5. STAMPING PROCESS

The piston stamping is done in order to recognize the piston’s make,

manufacturing company, the piston’s dimensions and the oversize of the

piston. Piston stamping is performed on the top of the piston head. It is done

in the opposite direction to the peg holes of the piston. A piston stamped in

the wrong direction is rejected in the inspection procedure.

An oversize of 0.4, 0.2, 0.25, 0.5 and 0.8mm is allowed on the piston stamp.

The various stamping details are shown in the diagram. (Refer Fig. 5.2.).

Fig.5.2. Piston Stamping aspects

5.6. PACKING PROCESS

The packing process of the piston is carried out after the inspection and the

stamping process. In the packing process, the assembly of the various parts of

the pistons are performed which include

• Ring Assembly

• Circlip Assembly, and,

• Gudgeon Pin Assembly

After the assembly is performed, the assembled piston is either O.E. Packed or

R.M. Packed using paper. O.E. Packing is used for mass scale packing.

Thus, once the packaging is complete, the pistons are dispatched to the

companies that ordered for them.

Thus, the journey of the piston at the factory comes to an end with this.

The death of the piston occurs when after its designated working period, the

piston is damaged due to various circumstances. A small glance at the various

conditions that lead to the piston failure, eventual death and replacement are

discussed in brief in the next chapter.

CHAPTER-6

PISTON FAILURE ANALYSIS

6.0 WORKING LIFE OF A PISTON

After the piston comes out of the factory, its life outside begins at an

automobile plant. It is assembled with its fellow engine parts and fitted into a

vehicle’s combustion chamber. Sealed tightly and connected with the

connecting rods and crankshaft, the life of the piston involves moving up and

down at incredible speeds.

The pistons work at speeds of up to 200 times per second. Also, the pistons

work at extremely high temperatures soaring up to 400-500°C.

Thus, at this level of exhaustive work in extreme conditions, the piston is

bound for fatigue and eventual damage, at which point, it is replaced.

The various types of piston failures are discussed briefly in the sub-topics of

this chapter.

6.1. HEAT SEIZURE

The seizure of the piston due to excessive heating conditions is known as

piston heat seizure (Refer Fig. 6.1.). This is due to the types of loads as follows:

• Excessive heat, over 1200F/650C EGT.

• Lean jetting or adjustments on carburetor.

• Incorrect loading on propeller allowing excessive RPM.

Fig.6.1. Heat seizure of a Piston

6.2. COLD SEIZURE

The seizure of the piston due to extremely cold working conditions is known as

cold seizure of a piston (Refer Fig.6.2.). It occurs due to the following reasons:

• Thermo-imbalance of piston and cylinder.

• Lack of warm-up.

• Excessive temperature difference inlet to outlet on engine.

Fig.6.2. Cold Seizure of a Piston

6.3. OIL FAILURE OR OIL FLASH

The failure caused by the oil and the excessive heat on the piston is known as

oil fatigue failure (Refer Fig.6.3.). It is caused due to the following reasons:

• High temp in engine from cooling system failure, fan belt,

coolant problems.

• Poor quality oils, auto, gear, unsuitable temperature stability

Fig.6.3. Oil Failure of a piston

6.4. LUBRICATION CONFLICTS

The failure caused due to the conflict of lubricating oils is called as lubrication

conflict failure (Refer Fig.6.4.). It occurs due to the following factors:

• Mixing of oils.

• Synthetic or Mineral mixture deposits.

• Chemical reaction between lubricants.

Fig.6.4. Lubrication Conflict failure

6.5. PISTON DOME BREAKOUT

The damage caused on the piston dome due to extremely devastating

conditions is known as piston dome breakout failure (Refer Fig.6.5.). It is

caused due to:

• Ignition timing failure.

• Erratic firing of spark plug.

• Lack of ignition damper points in engines.

Fig.6.5. Piston Dome Breakout

6.6. PISTON FRACTURE

The damage due to,

• Excessive wear.

• Excessive RPM with no load.

• Excessive clearance fitting.

by which the piston completely fractures is known as piston fracture (Refer

Fig.6.6.). This is eventual last stage of a piston’s life. Complete disassembly is

required to remove all material and piston replacement is the only solution to

this failure.

Fig.6.6. Piston Fracture

So, as discussed above, the various types of damages that are caused to a

piston and the impact of those damages leading to failure have been

understood.

With the end of this chapter, the end of a piston’s life is demonstrated. A

piston that was once an idea, was designed, manufactured, inspected,

packaged, dispatched, assembled and used until its failure led to its eventual

death. Thus, the piston will be replaced and the scrap of the piston will be

recycled.

Thus, this ends the life cycle of a piston. The life cycle which consists of a

service of the range of 50,000 KMS- 1,00,000 KMS comes to an end.

Nevertheless, this is not the end of the project report.

The project report extends itself into the next chapter where the phases of a

piston life are assessed. The final chapter of this project work report deal with

how a piston’s life can be improved and how one can get more miles out a

single piston. Effectively, the next chapter deals with The Improvement

Aspects and Future Plans of Pistons.

CHAPTER-7

IMPROVEMENTS AND FUTURE PLANS

7.0. WHAT HAS BEEN UNDERSTOOD

From the thorough explanations provided in the preceding chapters, the life

cycle of a piston is clearly depicted and understood. What has been

understood is that the depth of ideas, the accuracy of designs, the flawlessness

in manufacture and the enervating use of the piston are the phases of the

piston life. Also, these phases depict the extreme levels of detailing that goes

into piston making.

Although, most of the things are understood, there are a few things that need

to be looked upon at with higher levels of focus and concentration. These

attributes relate to the change in design, improvements in manufacturing and

developing the working conditions to suitable levels. All these factors lead to

the enhancement of the piston life and help us gain more out a single piston.

These improvements are discussed as future prospects in piston production,

and make room for better quality of products delivered. The aspects of

improvements and future plans are discussed in the next phase of this chapter.

7.1. IMPROVEMENTS

The various aspects in piston production that can be worked upon and

improved to enhance the piston are known as Improvement Factors.

There are many factors of improvements that can be made in piston

production. A few prospects are illustrated as follows.

7.1.1. Piston anti-friction coatings:

Regardless of the world region, today's automotive industry faces multiple

challenges for higher mileage, lower emissions and extended vehicle service

intervals. This can be achieved by dry-film anti-friction coatings, efficiently

applied on piston skirts and rings can help achieve these goals while replacing

tin plating and other, more expensive, less effective wear treatments.

Combined with specialized, high-volume application processes, Molykote Anti-

Friction Coatings, bond strongly with ferrous, aluminum and composite-metal

surfaces to provide long-term lubrication and improve engine performance.

These paint like materials with submicron-sized particles of solid lubricants:

• Reduce metal-to-metal friction, engine noise, scuffing and wear.

• Provide critical engine lubrication during start-up when oil splash

is unavailable.

• Aid combustion efficiency to help improve fuel economy and

reduce emissions.

7.1.2. Tighter Piston to Cylinder Wall Clearances:

• To reduce the blow-by (from the combustion chamber to crankcase).

• Reduce the reverse blow-by (from the crankcase to the combustion

chamber on the intake stroke).

• Achieve better burn efficiency, and,

• Reduce emissions.

Piston rings must seal (for good compression pressures and prevent oil from

getting into the chamber) , have shorter break-in period, and wear the walls

less despite being closer.

These requirements must be of primary priority for making new alloys and

coatings for pistons and rings to make them withstand the higher tolerances

demanded by the design requirements.

Next discussed, are the future prospects of piston and piston ring

development.

7.2. FUTURE PLANS

The future of the piston development lies within the design attribute of

pistons. By changing the design of the piston and piston rings, the lifespan and

efficiency can be dramatically improved as it shall be seen in the following

passage.

7.2.1. THE LKZ RING

An oil ring tech, known as an LKZ ring, not only can reduce oil consumption by

50 percent, but also reduces frictional losses by 15 percent (compared to

standard conventional oil ring designs).

The altercation lies in the point that where traditional rings apply equal

pressure on the downstroke and upstroke, the new ring design primarily

provides pressure on the downstroke. The surface inside the piston bore also

employs a unique design, offering a tapered, two-step surface (versus an

untapered surface in standard oil rings) (Refer Fig.7.1.).

Fig.7.1. Standard Oil Ring vs. LKZ Ring

The result is that oil is more effectively returned to the oil pan, reducing the

amount of oil that enters the combustion chamber. The less oil entering the

combustion chamber, the better, as this has numerous undesirable effects,

such as wasting oil via combustion and coating the spark plugs with carbon by-

products, reducing their ability to combust gasoline. The improved oil

performance also leads to better cylinder lubrication and less friction.

The direction of future piston development include lightweight alloy wrist

pins, more anodizing and/or the use of ceramic coatings on the tops of pistons

and upper ring groove to improve heat resistance and wear, and maybe top

rings with no end gaps

The best indication of what the future plans are is to look at today's state-of-

the-art racing pistons. Super lightweight designs with almost no skirts, holes

machined into the sides to reduce weight, and various design tricks to control

thermal expansion and detonation under high load. Also, one may see some

exotic graphite reinforced pistons for certain high output engines similar to

ones that are now being used in diesel engines.

Thus, this completes the study of the improvements and the future plans of

the piston development. All the factors, if implemented correctly, can lead to a

improvement in piston life of up to 50,000 KMS.

7.3. CONCLUSION

Thus, this concludes the project report on the life cycle of a piston and piston

rings. With the insight into what happens and what can be improved in

piston production and use, this project report can be a source of future

improvement in piston efficiency which in turn is the direct improvement of

the Automobile as a whole.