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COURSE PREPARED BY M.JAYAPRASAD MATERIALS, MANUFACTURING AND TESTING OF ENGINE
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Page 1: Materials 1

COURSE PREPARED BYM.JAYAPRASAD

MATERIALS, MANUFACTURING AND TESTING OF ENGINE

Page 2: Materials 1

221076 MATERIALS, MANUFACTURING AND TESTING OF ENGINE L T P C 3 0 0 3

AIM: To know the engine materials, manufacturing methodology and testing methodology.OBJECTIVE: To provide knowledge on engine materials, manufacturing and testing of engine components.

UNIT I MATERIALS 7

Selection – types of Materials – Ferrous – Carbon and Low Alloy steels, High Alloy Steels, Cast Irons – Non Ferrous – Aluminium, Magnesium, Titanium, Copper and Nickel alloys.

UNIT II ENGINE COMPONENTS 15

Cylinder Block, Cylinder Head, Crankcase and Manifolds, Piston Assembly, Connecting Rod, Crankshaft, Camshaft And Valve Train - Production methods – Casting, Forging, Powder Metallurgy – Machining – Testing Methods.

UNIT III ENGINE AUXILIARIES 7Carburettors, fuel injection system components, radiators, fans, coolant pumps, ignition System.

UNIT IV COMPUTER INTEGRATED MANUFACTURING 7

Integration of CAD, CAM and CIM- Networking, CNC programming for machining ofEngine Components.

UNIT V QUALITY AND TESTING 9

TS 16949, B I S codes for testing. Instrumentation, computer aided engine testing, metrology for manufacturing Engine Components.

TEXT BOOKS : TOTAL: 45 PERIODS

Page 3: Materials 1

1. Grover, M.P., CAD/CAM, Prentice Hall of India Ltd., 1985.2. Heldt, P.M., High speed internal combustion engines, Oxford & IBH Publishing Co., 1960.3. Judge, A.W., Testing of high speed internal combustion engines,

Chapman & Hall., 1960.

REFERENCE BOOKS:1. Richard, W., He ine Carl R. Loper Jr. and Philip, C., Rosentha l , Principles of Metal Casting, McGraw-Hill Book Co., 1980.2. IS: 1602 – 1960 Code for testing of variable speed internal Combustion engines for Automobile Purposes, 1966.3. SAE Handbook, 1994.4. P.Radhakrishnan and S.Subramaniyan, CAD/CAM/CIM, New Age

International (P) Limited, Publishers, 1997.5 .Mikett P.Groover, Automation, production Systems and Computer – Integrated Manufacturing Printice Hall of India Private Limited, 1999.

Page 4: Materials 1

UNIT I MATERIALS

Low carbon steels

.Low carbon steel contains approximately 0.05–0.15% carbon and mild steel contains

0.16–0.29% carbon, therefore it is neither brittle nor ductile. Mild steel has a relatively

low tensile strength, but it is cheap and malleable; surface hardness can be increased

through carburizing. The density of mild steel is approximately 7.85 g/cm3 and the

Young's modulus is 210,000 MPa If low carbon steel is only stressed to some point

between the upper and lower yield point then the surface may develop Lüder bands.

Medium carbon steel

Approximately 0.30–0.59% carbon content. Balances ductility and strength and has good

wear resistance; used for large parts, forging and automotive components

Higher carbon steels

Higher carbon steels Carbon steels which can successfully undergo heat-treatment have

carbon content in the range of 0.30–1.70% by weight. Trace impurities of various other

elements can have a significant effect on the quality of the resulting steel. Trace amounts

of sulfur in particular make the steel red-short. Low alloy carbon steel, such as A36

grade, contains about 0.05% sulfur and melts around 1,426–1,538 °C (2,599–2,800 °F).

Manganese is often added to improve the hardenability of low carbon steels.

Ultra-high carbon steel

Approximately 1.0–2.0% carbon content. Steels that can be tempered to great hardness.

Used for special purposes like (non-industrial-purpose) knives, axles or punches. Most

steels with more than 1.2% carbon content are made using powder metallurgy. Note that

steel with carbon content above 2.0% is considered cast iron.

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Alloy steel

Alloy steel is steel alloyed with a variety of elements in total amounts of between 1.0%

and 50% by weight to improve its mechanical properties. Alloy steels are classified into

two groups: low alloy steels and high alloy steels. The following are a range of improved

properties in alloy steels (as compared to carbon steels): strength, hardness, toughness,

wear resistance, hardenability, and hot hardness. In order to achieve some of these

improved properties the metal may require heat treating.

Common alloyants include manganese (the most-common one), nickel, chromium,

molybdenum, vanadium, silicon, and boron. Less common alloyants include aluminum,

cobalt, copper, cerium, niobium, titanium, tungsten, tin, and zirconium.

Some of these find uses in exotic and highly-demanding applications, such as in the

turbine blades of jet engines, in spacecraft, and in nuclear reactors. Because of the

ferromagnetic properties of iron, some steel alloys find important applications where their

responses to magnetism are very important, including in electric motors and in

transformers,

Cast iron

Cast iron usually refers to grey iron, but also identifies a large group of ferrous alloys,

which solidify with a eutectic. The colour of a fractured surface can be used to identify an

alloy. White cast iron is named after its white surface when fractured, due to its carbide

impurities which allow cracks to pass straight through. Grey cast iron is named after its

grey fractured surface, which occurs because the graphitic flakes deflect a passing crack

and initiate countless new cracks as the material rupture.

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Carbon (C) and silicon (Si) are the main alloying elements, with the amount ranging from

2.1 to 4 wt% and 1 to 3 wt%, respectively. While this technically makes these base alloys

ternary Fe-C-Si alloys, the principle of cast iron solidification is understood from the

binary iron-carbon phase diagram. Since the compositions of most cast irons are around

the eutectic point of the iron-carbon system, the melting temperatures closely correlate,

usually ranging from 1,150 to 1,200 °C (2,102 to 2,192 °F), which is about 300 °C (572

°F) lower than the melting point of pure iron.

Cast iron tends to be brittle, except for malleable cast irons. With its relatively low

melting point, good fluidity, castability, excellent machinability, resistance to

deformation and wear resistance, cast irons have become an engineering material with a

wide range of applications and are used in pipes, machines and automotive industry parts,

such as cylinder heads (declining usage), cylinder blocks and gearbox cases (declining

usage). It is resistant to destruction and weakening by oxidisation (rust).

Grey cast iron

Grey cast iron is characterized by its graphitic microstructure, which causes fractures of

the material to have a grey appearance. It is the most commonly used cast iron and the

most widely use cast material based on weight. Most cast irons have a chemical

composition of 2.5 to 4.0% carbon, 1 to 3% silicon, and the remainder is iron. Grey cast

iron has less tensile strength and shock resistance than steel, however its compressive

strength is comparable to low and medium carbon steel.

White cast iron

With a lower silicon content and faster cooling, the carbon in white cast iron precipitates

out of the melt as the metastable phase cementite, Fe3C, rather than graphite. The

cementite which precipitates from the melt forms as relatively large particles, usually in a

eutectic mixture, where the other phase is austenite (which on cooling might transform to

martensite). These eutectic carbides are much too large to provide precipitation hardening

(as in some steels, where cementite precipitates might inhibit plastic deformation by

impeding the movement of dislocations through the ferrite matrix). Rather, they increase

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the bulk hardness of the cast iron simply by virtue of their own very high hardness and

their substantial volume fraction, such that the bulk hardness can be approximated by a

rule of mixtures. In any case, they offer hardness at the expense of toughness. Since

carbide makes up a large fraction of the material, white cast iron could reasonably be

classified as a cermet. White iron is too brittle for use in many structural components, but

with good hardness and abrasion resistance and relatively low cost, it finds use in such

applications as the wear surfaces (impeller and volute) of slurry pumps, shell liners and

lifter bars in ball mills and autogenous grinding mills, balls and rings in coal pulverisers,

and the teeth of a backhoe's digging bucket (although cast medium-carbon martensitic

steel is more common for this application).

It is difficult to cool thick castings fast enough to solidify the melt as white cast iron all

the way through. However, rapid cooling can be used to solidify a shell of white cast

iron, after which the remainder cools more slowly to form a core of grey cast iron. The

resulting casting, called a chilled casting, has the benefits of a hard surface and a

somewhat tougher interior.

High-chromium white iron alloys allow massive castings (for example, a 10-tonne

impeller) to be sand cast, i.e., a high cooling rate is not required, as well as providing

impressive abrasion resistance.[citation needed]

Malleable cast iron

Malleable iron starts as a white iron casting that is then heat treated at about 900 °C

(1,650 °F). Graphite separates out much more slowly in this case, so that surface tension

has time to form it into spheroidal particles rather than flakes. Due to their lower aspect

ratio, spheroids are relatively short and far from one another, and have a lower cross

section vis-a-vis a propagating crack or phonon. They also have blunt boundaries, as

opposed to flakes, which alleviates the stress concentration problems faced by grey cast

iron. In general, the properties of malleable cast iron are more like mild steel. There is a

limit to how large a part can be cast in malleable iron, since it is made from white cast

iron.

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Non Ferrous

Aluminium is a soft, durable, lightweight, ductile and malleable metal with appearance

ranging from silvery to dull gray, depending on the surface roughness. Aluminium is

nonmagnetic and non sparking. It is also insoluble in alcohol, though it can be soluble in

water in certain forms. The yield strength of pure aluminium is 7–11 MPa, while

aluminium alloys have yield strengths ranging from 200 MPa to 600 MPa. Aluminium

has about one-third the density and stiffness of steel. It is easily machined, cast, drawn

and extruded.

Corrosion resistance can be excellent due to a thin surface layer of aluminium oxide that

forms when the metal is exposed to air, effectively preventing further oxidation. The

strongest aluminium alloys are less corrosion resistant due to galvanic reactions with

alloyed copper. This corrosion resistance is also often greatly reduced when many

aqueous salts are present, particularly in the presence of dissimilar metals.

Aluminium atoms are arranged in a face-centered cubic (FCC) structure. Aluminium has

stacking-fault energy of approximately 200 mJ/m2.

Aluminium is one of the few metals that retain full silvery reflectance in finely powdered

form, making it an important component of silver paints. Aluminium mirror finish has the

highest reflectance of any metal in the 200–400 nm (UV) and the 3,000–10,000 nm (far

IR) regions; in the 400–700 nm visible range it is slightly outperformed by tin and silver

and in the 700–3000 (near IR) by silver, gold, and copper.

Applications

Transportation (automobiles, aircraft, trucks, railway cars, marine vessels, bicycles etc.)

as sheet, tube, castings etc. Packaging (cans, foil, etc.)

Construction (windows, doors, siding, building wire, etc.)

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A wide range of household items, from cooking utensils to baseball bats, watches.

Street lighting poles, sailing ship masts, walking poles etc.

Outer shells of consumer electronics, also cases for equipment e.g. photographic

equipment.

Electrical transmission lines for power distribution

MKM steel and Alnico magnets

Super purity aluminium (SPA, 99.980% to 99.999% Al), used in electronics and CDs.

Heat sinks for electronic appliances such as transistors and CPUs.

Substrate material of metal-core copper clad laminates used in high brightness LED

lighting.

Powdered aluminium is used in paint, and in pyrotechnics such as solid rocket fuels and

thermite. Aluminium can be reacted with hydrochloric acid to form hydrogen gas.

A variety of countries, including France, Italy, Poland, Finland, Romania, Israel, and the

former Yugoslavia, have issued coins struck in aluminium or aluminium-copper alloys.

Some guitar models sports aluminium diamond plates on the surface of the instruments,

usually either chrome or black. Kramer Guitars and Travis Bean are both known for

having produced guitars with necks made of aluminium, which gives the instrument a

very distinct sound.

Magnesium

Physical and chemical properties Elemental magnesium is a fairly strong, silvery-white,

light-weight metal (two thirds the density of aluminium). It tarnishes slightly when

exposed to air, although unlike the alkali metals, storage in an oxygen-free environment

is unnecessary because magnesium is protected by a thin layer of oxide that is fairly

impermeable and hard to remove. Like its lower periodic table group neighbor calcium,

magnesium reacts with water at room temperature, though it reacts much more slowly

than calcium. When it is submerged in water, hydrogen bubbles will almost unnoticeably

begin to form on the surface of the metal, though if powdered it will react much more

rapidly. The reaction will occur faster with higher temperatures (see precautions).

Magnesium also reacts exothermically with most acids, such as hydrochloric acid (HCl).

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As with aluminium, zinc and many other metals, the reaction with hydrochloric acid

produces the chloride of the metal and releases hydrogen gas.

Magnesium compounds are typically white crystals. Most are soluble in water, providing

the sour-tasting magnesium ion Mg2+. Small amounts of dissolved magnesium ion

contribute to the tartness and taste of natural waters. Magnesium ion in large amounts is

an ionic laxative, and magnesium sulfate (common name: Epsom salt) is sometimes used

for this purpose. So-called "milk of magnesia" is a water suspension of one of the few

insoluble magnesium compounds, magnesium hydroxide. The undissolved particles give

rise to its appearance and name. Milk of magnesia is a mild base commonly used as an

antacid, which has some laxative side effect

Magnesium Applications

Niche and illustrative uses of magnesium compounds Magnesium hydroxide is used in

milk of magnesia, its chloride, oxide, gluconate, malate, orotate and citrate used as oral

magnesium supplements, and its sulfate (Epsom salts) for various purposes in medicine,

and elsewhere. Oral magnesium supplements have been claimed to be therapeutic for

some individuals who suffer from Restless Leg Syndrome (RLS).

Magnesium borate, magnesium salicylate and magnesium sulfate are used as antiseptics.

Magnesium bromide is used as a mild sedative (this action is due to the bromide, not the

magnesium).

Magnesium carbonate (MgCO3) powder is also used by athletes, such as gymnasts and

weightlifters, to improve the grip on objects – the apparatus or lifting bar.

Magnesium stearate is a slightly flammable white powder with lubricating properties. In

pharmaceutical technology it is used in the manufacturing of tablets, to prevent the tablets

from sticking to the equipment during the tablet compression process (i.e., when the

tablet's substance is pressed into tablet form).

Magnesium sulfite is used in the manufacture of paper (sulfite process).

Magnesium phosphate is used to fireproof wood for construction.

Magnesium hexafluorosilicate is used in mothproofing of textiles.

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Titanium

A metallic element, titanium is recognized for its high strength-to-weight ratio. It is a

strong metal with low density that is quite ductile (especially in an oxygen-free

environment), lustrous, and metallic-white in color. The relatively high melting point

(more than 1,650 °C or 3,000 °F) makes it useful as a refractory metal. It is paramagnetic

and has fairly low electrical and thermal conductivity.

It is fairly hard (although not as hard as some grades of heat-treated steel), non-magnetic

and a poor conductor of heat and electricity. Machining requires precautions, as the

material will soften and gall if sharp tools and proper cooling methods are not used. Like

those made from steel, titanium structures have a fatigue limits which guarantees

longevity in some applications. Titanium alloys specific stiffnesses are also usually not as

good as other materials such as aluminium alloys and carbon fiber, so it is used less for

structures which require high rigidity.

The metal is a dimorphic allotrope whose hexagonal alpha form changes into a body-

centered cubic (lattice) β form at 882 °C (1,620 °F). The specific heat of the alpha form

increases dramatically as it is heated to this transition temperature but then falls and

remains fairly constant for the β form regardless of temperature. Similar to zirconium and

hafnium, an additional omega phase exists, which is thermodynamically stable at high

pressures, but is metastable at ambient pressures. This phase is usually hexagonal (ideal)

or trigonal (distorted) and can be viewed as being due to a soft longitudinal acoustic

phonon of the β phase causing collapse of (111) planes of atoms.

Applications

Pigments, additives and coatings

Aerospace and marine

Industrial

Consumer and architectural

Medical Orthopedic implants

Piercing

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Copper

Occupies the same family of the periodic table as silver and gold, since they each have

one s-orbital electron on top of a filled electron shell which forms metallic bonds. Like

silver and gold, copper is easily worked, being both ductile and malleable. The ease with

which it can be drawn into wire makes it useful for electrical work as does its excellent

electrical conductivity. Copper is normally supplied, as with nearly all metals for

industrial and commercial use, in a fine grained polycrystalline form. Polycrystalline

metals have greater strength than monocrystalline forms, and the difference is greater for

smaller grain (crystal) sizes.

In direct mechanical contact with metals of different electropotential (for example, a

copper pipe joined to an iron pipe), especially in the presence of moisture, as the

completion of an electrical circuit (for instance through the common ground) will cause

the juncture to act as an electrochemical cell (like a single cell of a battery). The weak

electrical currents themselves are harmless but the electrochemical reaction will cause the

conversion of the iron to other compounds, eventually destroying the functionality of the

union.

Copper does not react with water, but it slowly reacts with atmospheric oxygen forming a

layer of brown-black copper oxide. In contrast to the oxidation of iron by wet air, this

oxide layer stops the further, bulk corrosion. A green layer of copper carbonate, called

verdigris, can often be seen on old copper constructions, such as the Statue of Liberty.

Copper reacts with hydrogen sulfide- and sulfide-containing solutions, forming various

copper sulfides on its surface. In sulfide-containing solutions, copper is less noble than

hydrogen and will corrode. This is observed in everyday life when copper metal surfaces

tarnish after exposure to air containing sulfur compounds.

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Copper is slowly dissolved in oxygen-containing ammonia solutions because ammonia

forms water-soluble complexes with copper. Copper reacts with a combination of oxygen

and hydrochloric acid to form a series of copper chlorides.

Copper reacts with an acidified mixture of hydrogen peroxide to form the corresponding

copper salt:

Uses

Electronics and related devices

Architecture and industry

Biomedical applications

Aquaculture applications

Nickel

Category: Nickel alloys

Alnico (aluminium, cobalt; used in magnets)

Alumel (nickel, manganese, aluminium, silicon)

Chromel (chromium)

Cupronickel (bronze, copper)

Ferronickel (nickel)

German silver (copper, zinc)

Hastelloy (molybdenum, chromium, sometimes tungsten)

Inconel (chromium, iron)

Monel metal (copper, iron, manganese)

Nichrome (chromium)

Nicrosil (chromium, silicon, magnesium)

Nisil (silicon)

Nitinol (titanium, shape memory alloy)

Soft magnetic alloys

Mu-metal (iron)

Page 14: Materials 1

Nickel is a silvery-white metal with a slight golden tinge that takes a high polish. It is one

of only four elements that are magnetic at or near room temperature. Its Curie

temperature is 355 °C. That is, nickel is non-magnetic above this temperature. The unit

cell of nickel is a face centered cube with the lattice parameter of 0.352 nm giving an

atomic radius of 0.124 nm. Nickel belongs to the transition metals and is hard and ductile.

Page 15: Materials 1

UNIT II ENGINE

Cylinder block is an integrated structure comprising the cylinder(s) of a reciprocating

engine and often some or all of their associated surrounding structures (coolant passages,

intake and exhaust passages and ports, and crankcase). The term engine block is often

used synonymously with "cylinder block"

In the basic terms of machine elements, the various main parts of an engine (such as

cylinder(s), cylinder head(s), coolant passages, intake and exhaust passages, and

crankcase) are conceptually distinct, and these concepts can all be instantiated as discrete

pieces that are bolted together. Such construction was very widespread in the early

decades of the commercialization of internal combustion engines (1880s to 1920s), and it

is still sometimes used in certain applications where it remains advantageous (especially

very large engines, but also some small engines). However, it is no longer the normal

way of building most petrol engines and diesel engines, because for any given engine

configuration, there are more efficient ways of designing for manufacture (and also for

maintenance and repair). These generally involve integrating multiple machine elements

into one discrete part, and doing the making (such as casting, stamping, and machining)

for multiple elements in one setup with one machine coordinate system (of a machine

tool or other piece of manufacturing machinery). This yields lower unit cost of

production (and/or maintenance and repair).

Today most engines for cars, trucks, buses, tractors, and so on are built with fairly highly

integrated design, so the words "monobloc" and "en bloc" are seldom used in describing

them; such construction is often implicit. Thus "engine block", "cylinder block", or

simply "block" are the terms likely to be heard in the garage or on the street.

Page 16: Materials 1

Cylinder Crown

Page 17: Materials 1

In an internal combustion engine, the cylinder head (often informally abbreviated to just

head) sits above the cylinders on top of the cylinder block. It consists of a platform

containing the poppet valves, spark plugs and usually part of the combustion chamber. In

a flathead engine, the mechanical parts of the valve train are all contained within the

block, and the head is essentially a flat plate of metal bolted to the top of the cylinder

bank with a head gasket in between; this simplicity leads to ease of manufacture and

repair, and accounts for the flathead engine's early success in production automobiles and

continued success in small engines, such as lawnmowers. This design, however, requires

the incoming air to flow through a convoluted path, which limits the ability of the engine

to perform at higher revolutions per minute (rpm), leading to the adoption of the

overhead valve (OHV) head design, and the subsequent overhead camshaft (OHC)

design.

Cylinder Crankcase

In an internal combustion engine of the reciprocating type, the crankcase is the housing

for the crankshaft. The enclosure forms the largest cavity in the engine and is located

below the cylinder(s), which in a multicylinder engine are usually integrated into one or

several cylinder blocks. Crankcases have often been discrete parts, but more often they

are integral with the cylinder bank(s), forming an engine block. Nevertheless, the area

around the crankshaft is still usually called the crankcase. Crankcases and other basic

engine structural components (e.g., cylinders, cylinder blocks, cylinder heads, and

integrated combinations thereof) are typically made of cast iron or cast aluminium via

sand casting. Today the foundry processes are usually highly automated, with a few

skilled workers to manage the casting of thousands of parts.

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A crankcase often has an opening in the bottom to which an oil pan is attached with a

gasket bolted joint. Some crankcase designs fully surround the crank's main bearing

journals, whereas many others form only one half, with a bearing cap forming the other.

Some crankcase areas require no structural strength from the oil pan itself (in which case

the oil pan is typically stamped from sheet steel), whereas other crankcase designs do (in

which case the oil pan is a casting in its own right). Both the crankcase and any rigid cast

oil pan often have reinforcing ribs cast into them, as well as bosses which are drilled and

tapped to receive mounting screws/bolts for various other engine parts.

Besides protecting the crankshaft and connecting rods from foreign objects, the crankcase

serves other functions, depending on engine type. These include keeping the motor oil

contained, usually hermetically or nearly hermetically (and in the hermetic variety,

allowing the oil to be pressurized); providing the rigid structure with which to join the

engine to the transmission; and in some cases, even constituting part of the frame of the

vehicle (such as in many farm tractors).

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Cylinder Manifold

Manifolds are used to connect two or more cylinders of gas together increasing the

supply volume available to provide a continuous flow when one cylinder is not sufficient

and a tube trailer or other bulk supply is not practical. Manifolds are also used when a

single cylinder of gas is not capable of supplying the required flow rate required by a

process.

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Piston Assembly

The main parts of a piston are:

1 The top, which may also called the Head or Crown .

2 The Ring belt.

3 The Pin bosses.

4 The Skirt.

The top is part of the Combustion chamber The top may be flat , or a combustion

chamber may be cut into the top of the piston, the top may be raised or have a bowl cut

into it. Soot contamination of the lubricating oil in Diesel engines is reduced when the

combustion chamber is located in the piston, as opposed to the Cylinder head .

The piston skirt, which wraps around the lower part of the piston, distributes the side

loads and prevents the piston from rocking in the cylinder . long pistons rock less than

short ones and are used in diesel engine to reduce the number of required compression

rings . The pin boss supports the piston pin and transmits the force of combustion to the

pin. it is one of the most highly loaded areas of the piston .The piston pin is usually

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hollow to reduce it's weight. The piston iS fitted with rings which ride in grooves cut in

the piston head to seal against gas leakage and control oil flow.

Piston Assembly

Pressure die casted, gravity die casted, shell moulded piston assembly are made out of

aluminium alloys, graded closed grained cast iron. Piston rings are individually

centrifugally casted out of high grade cast iron materials. Models available off shelf.

Packing/Piston Rings

We manufacture Carbon Packing Rings which are used in steam, Turbine, Water

Turbine, gas Turbine for different type of industries like Sugar, Cement, Textiles, Power

Plant and Electricity Board etc. These packing rings are of various types and size used in

turbine of various kind also the piston Rings which are also used in Compressors not only

as the Piston Rod Packing but also as the components of Pistons, Piston Rings and Guide

Rings. Carbon glands are used in the sealing of liquids and gases, restricting leakage to a

minimum. Carbon gland rings are provides an economical simple and effective seal on

impulse turbines, water turbines, steam turbines, gas turbines, low pressure fans and

blowers.

Piston Assemblies

In-house Manufacturing, Supplied with Piston Pin

Range: Over 1000 types

Material: Available in LM13, LM17 and LM21 material.

Type: Normal type, Ring Carrier type, Oil cooling gallery type, All types of coatings also

available.

Size Range: 60 mm to 175 bore size

Manufacturing Process: Automatic Die casting, T9 Heat Treated

Machining: On CNC and SPM

Installed Capacity: 25000 per month

Sample Development: 8 weeks, No tooling costs charged for order above 300 Pieces

Product Quality: OEM and after market

Page 22: Materials 1

Connecting rod

In a reciprocating piston engine, the connecting rod or conrod connects the piston to the

crank or crankshaft. Together with the crank, they form a simple mechanism that

converts linear motion into rotating motion.

Connecting rods may also convert rotating motion into linear motion. Historically, before

the development of engines, they were first used in this way.

As a connecting rod is rigid, it may transmit either a push or a pull and so the rod may

rotate the crank through both halves of a revolution, i.e. piston pushing and piston

pulling. Earlier mechanisms, such as chains, could only pull. In a few two-stroke engines,

the connecting rod is only required to push.

Today, connecting rods are best known through their use in internal combustion piston

engines, such as car engines. These are of a distinctly different design from earlier forms

of connecting rods, used in steam engines and steam locomotives

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While the two competing forging processes are similar, there are a number of subtle

differences between the two. The forged steel rod is fabricated by starting with a wrought

steel billet, heating the billet and forging it in the material’s plastic temperature range,

fracturing or cutting the rod cap end, and then machining portions of the product to

realize the final dimensional characteristics of the component.

The powder forged (PF) rod is: fabricated by consolidating metal powders into a perform

that is sintered, reheated to forging temperature (or in some cases forged subsequently to

sintering), fully densified by forging to final shape, fracturing of the rod cap end, and

then machined (minimally) to final dimensions.

A new steel, C-70, has been introduced from Europe as a crackable forging steel.

Alloying elements in the material enable hardening of forged connecting rods when they

undergo controlled cooling after forging. This material fractures in a fashion similar to

powder forged materials.

Crankshaft

The crankshaft, sometimes casually abbreviated to crank, is the part of an engine which

translates reciprocating linear piston motion into rotation. To convert the reciprocating

motion into rotation, the crankshaft has "crank throws" or "crankpins", additional bearing

surfaces whose axis is offset from that of the crank, to which the "big ends" of the

connecting rods from each cylinder attach.

It typically connects to a flywheel, to reduce the pulsation characteristic of the four-stroke

cycle, and sometimes a torsional or vibrational damper at the opposite end, to reduce the

torsion vibrations often caused along the length of the crankshaft by the cylinders farthest

from the output end acting on the torsional elasticity.

Page 24: Materials 1

Crankshafts materials should be readily shaped, machined and heat-treated, and have

adequate strength, toughness, hardness, and high fatigue strength. The crankshaft are

manufactured from steel either by forging or casting. The main bearing and connecting

rod bearing liners are made of babbitt, a tin and lead alloy. Forged crankshafts are

stronger than the cast crankshafts, but are more expensive. Forged crankshafts are made

from SAE 1045 or similar type steel. Forging makes a very dense, tough shaft with a

grain running parallel to the principal stress direction. Crankshafts are cast in steel,

modular iron or malleable iron. The major advantage of the casting process is that

crankshaft material and machining costs are reduced because the crankshaft may be made

close to the required shape and size including counterweights. Cast crankshafts can

handle loads from all directions as the metal grain structure is uniform and random

throughout. Counterweights on cast crankshafts are slightly larger than counterweights on

forged crankshafts because the cast metal is less dense and therefore somewhat lighter.

Crankshaft Materials

Manganese-molybdenum Steel

1%-Chromium-molybdenum Steel

2.5%-Nickel-chromium-molybdenum Steel

3%-Chromium-molybdenum or 1.5%-Chromium-aluminium-modybdenum Steel.

Nodular Cast Irons

Page 25: Materials 1

1. HARDENABLE IRON

This is Grade 17 cast iron with an addition of 1% chrome to create 5 to 7% free carbide.

After casting, the material is flame/or induction hardened, to give a Rockwell hardness of

52 to 56 on the C Scale. This material was developed in the 1930’s in America as a low-

cost replacement for steel camshafts and is mainly suited in applications where there is an

excess of oil, i.e., camshafts that run in the engine block and that are splash-fed from the

sump. (This is the material that the Ford OHC camshafts were manufactured from).

It is not the most suitable material for performance camshafts in OHC engines. As a

company, we only use this material for performance camshafts if the camshaft is splash-

fed in the sump.

2. SPHEROIDAL GRAPHITE CAST IRON KNOWN AS SG IRONA material giving similar characteristics to hardenable. Its failing as a camshaft material

is hardness in its cast form, i.e., Rockwell 5, which tends to scuff bearings in adverse

conditions. The material will heat treat to 52 to 58 RockwellC. This material was used by

Fiat in the 1980’s.

3. CHILLED CHROME CAST IRON

Chilled iron is Grade 17 cast iron with 1% chrome. When the camshaft is cast in the

foundry, machined steel moulds the shape of the cam lobe are incorporated in the mould.

When the iron is poured, it hardens off very quickly (known as chilling), causing the cam

lobe material to form a matrix of carbide (this material will cut glass) on the cam lobe.

This material is exceedingly scuff-resistant and is the only material for producing

quantity OHC performance camshafts.

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Valve train

Term used to describe the mechanisms and parts which control the operation of the

valves. A traditional reciprocating internal combustion engine uses valves to control air

and fuel flow into and out of the cylinders, facilitating combustion.

Production Methods - Castings

Anchor Bronze & Metals Continuous Cast bronze is produced in stationary mold

continuous casting machines. All of the melting is done via electric induction crucible

furnaces. Melting occurs continuously, throughout the course of a production run.

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Molten metal is poured into a crucible tundish furnace having a controlled atmosphere

(A) The tundish furnace maintains a large reservoir (B) of molten metal at a controlled

temperature above a water-cooled graphite die (C). Any dross entering the tundish

furnace quickly floats to the top of the metal bath where it is removed.

Metal enters the freezing zone of the die (D) at a temperature in sufficient excess of the

liquidus to assure that any shrinkage pores in prior cast material are filled. This is

accomplished in a fraction of a second before rapid freezing begins. Severe segregation

of alloying elements is thereby avoided. Special patented techniques further reduce

segregation and greatly improve casting strength by generating a fine grain structure in

the casting.

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The newly frozen layer of metal shrinks rapidly away from the graphite die and is

withdrawn from the die by a set of electrically driven pinch rolls.

As the newly solidified portion of the casting leaves the freezing zone, the die is gravity

filled (E) with molten metal from the tundish. The solidification process begins again.

When the casting has attained the desired length, it is cut off with a flying saw positioned

below the pinch rolls. This process is used for production of intricate inside diameter

and/or outside diameter shapes. The vertical casting process is preferred for the

production of precision tubing. Tube concentricity of vertically cast product surpasses

that produced by all other metal working processes.

Advantages and disadvantages

Forging is a manufacturing process involving the shaping of metal using localized

compressive forces. Forging is often classified according to the temperature at which it is

performed: '"cold," "warm," or "hot" forging. Forged parts can range in weight from less

than a kilogram to 580 metric tons Forged parts usually require further processing to

achieve a finished part.

Forging can produce a piece that is stronger than an equivalent cast or machined part. As

the metal is shaped during the forging process, its internal grain deforms to follow the

general shape of the part. As a result, the grain is continuous throughout the part, giving

rise to a piece with improved strength characteristics.

Some metals may be forged cold, however iron and steel are almost always hot forged.

Hot forging prevents the work hardening that would result from cold forging, which

would increase the difficulty of performing secondary machining operations on the piece.

Also, while work hardening may be desirable in some circumstances, other methods of

Page 29: Materials 1

hardening the piece, such as heat treating, are generally more economical and more

controllable. Alloys that are amenable to precipitation hardening, such as most

aluminium alloys and titanium, can be hot forged, followed by hardening

Production forging involves significant capital expenditure for machinery, tooling,

facilities and personnel. In the case of hot forging, a high temperature furnace (sometimes

referred to as the forge) will be required to heat ingots or billets. Owing to the

massiveness of large forging hammers and presses and the parts they can produce, as well

as the dangers inherent in working with hot metal, a special building is frequently

required to house the operation. In the case of drop forging operations, provisions must

be made to absorb the shock and vibration generated by the hammer. Most forging

operations will require the use of metal-forming dies, which must be precisely machined

and carefully heat treated to correctly shape the workpiece, as well as to withstand the

tremendous forces involved.

Drop forging Drop forging is a forging process where a hammer is raised up and then

"dropped" onto the workpiece to deform it according to the shape of the die. There are

two types of drop forging: open-die drop forging and closed-die drop forging. As the

names imply, the difference is in the shape of the die, with the former not fully enclosing

the workpiece, while the latter does

Press forging Press forging works by slowly applying a continuous pressure or force,

which differs from the near-instantaneous impact of drop-hammer forging. The amount

of time the dies are in contact with the workpiece is measured in seconds (as compared to

the milliseconds of drop-hammer forges). The press forging operation can be done either

cold or hot.

The main advantage of press forging, as compared to drop-hammer forging, is its ability

to deform the complete workpiece. Drop-hammer forging usually only deforms the

surfaces of the workpiece in contact with the hammer and anvil; the interior of the

workpiece will stay relatively undeformed. Another advantage to the process includes the

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knowledge of the new part's strain rate. We specifically know what kind of strain can be

put on the part, because the compression rate of the press forging operation is controlled.

There are a few disadvantages to this process, most stemming from the workpiece being

in contact with the dies for such an extended period of time. The operation is a time

consuming process due to the amount of steps and how long each of them take. The

workpiece will cool faster because the dies are in contact with workpiece; the dies

facilitate drastically more heat transfer than the surrounding atmosphere. As the

workpiece cools it becomes stronger and less ductile, which may induce cracking if

deformation continues. Therefore heated dies are usually used to reduce heat loss,

promote surface flow, and enable the production of finer details and closer tolerances.

The workpiece may also need to be reheated. When done in high productivity, press

forging is more economical than hammer forging. The operation also creates closer

tolerances. In hammer forging a lot of the work is absorbed by the machinery, when in

press forging, the greater percentage of work is used in the work piece. Another

advantage is that the operation can be used to create any size part because there is no

limit to the size of the press forging machine. New press forging techniques have been

able to create a higher degree of mechanical and orientation integrity. By the constraint of

oxidation to the outer most layers of the part material, reduced levels of micro cracking

take place in the finished part.

Press forging can be used to perform all types of forging, including open-die and

impression-die forging. Impression-die press forging usually requires less draft than drop

forging and has better dimensional accuracy. Also, press forgings can often be done in

one closing of the dies, allowing for easy automation

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Upset forging Upset forging increases the diameter of the workpiece by compressing its

length. Based on number of pieces produced this is the most widely used forging process.

A few examples of common parts produced using the upset forging process are engine

valves, couplings, bolts, screws, and other fasteners.

Upset forging is usually done in special high speed machines called crank presses, but

upsetting can also be done in a vertical crank press or a hydraulic press. The machines are

usually set up to work in the horizontal plane, to facilitate the quick exchange of work

pieces from one station to the next. The initial workpiece is usually wire or rod, but some

machines can accept bars up to 25 cm (9.8 in) in diameter and a capacity of over 1000

tons. The standard upsetting machine employs split dies that contain multiple cavities.

The dies open enough to allow the workpiece to move from one cavity to the next; the

dies then close and the heading tool, or ram, then moves longitudinally against the bar,

upsetting it into the cavity. If all of the cavities are utilized on every cycle then a finished

part will be produced with every cycle, which is why this process is ideal for mass

production.

The following three rules must be followed when designing parts to be upset forged:

The length of unsupported metal that can be upset in one blow without injurious buckling

should be limited to three times the diameter of the bar.

Lengths of stock greater than three times the diameter may be upset successfully

provided that the diameter of the upset is not more than 1.5 times the diameter of the

stock.

In an upset requiring stock length greater than three times the diameter of the stock, and

where the diameter of the cavity is not more than 1.5 times the diameter of the stock, the

length of unsupported metal beyond the face of the die must not exceed the diameter of

the bar.

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The process starts by heating up the bar to 1,200 to 1,300 °C (2,192 to 2,372 °F) in less

than 60 seconds using high power induction coils. It is then descaled with rollers, sheared

into blanks, and transferred several successive forming stages, during which it is upset,

preformed, final forged, and pierced (if necessary). This process can also be couple with

high speed cold forming operations. Generally, the cold forming operation will do the

finishing stage so that the advantages of cold-working can be obtained, while maintaining

the high speed of automatic hot forging.

Roll forging Roll forging is a process where round or flat bar stock is reduced in

thickness and increased in length. Roll forging is performed using two cylindrical or

semi-cylindrical rolls, each containing one or more shaped grooves. A heated bar is

inserted into the rolls and when it hits a stop the rolls rotate and the bar is progressively

shaped as it is rolled out of the machine. The work piece is then transferred to the next set

of grooves or turned around and reinserted into the same grooves. This continues until the

desired shape and size is achieved. The advantage of this process is there is no flash and

it imparts a favorable grain structure into the workpiece.

Powder metallurgy is a forming and fabrication technique consisting of three major

processing stages. First, the primary material is physically powdered, divided into many

small individual particles. Next, the powder is injected into a mold or passed through a

die to produce a weakly cohesive structure (via cold welding) very near the dimensions of

the object ultimately to be manufactured. Pressures of 10-50 tons per square inch are

commonly used. Also, to attain the same compression ratio across more complex pieces,

it is often necessary to use lower punches as well as an upper punch. Finally, the end part

is formed by applying pressure, high temperature, long setting times (during which self-

welding occurs), or any combination thereof.

Two main techniques used to form and consolidate the powder are sintering and metal

injection molding. Recent developments have made it possible to use rapid

manufacturing techniques which use the metal powder for the products. Because with this

technique the powder is melted and not sintered, better mechanical strength can be

accomplished.

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Solid state sintering is the process of taking metal in the form of a powder and placing it

into a mold or die. Once compacted into the mold the material is placed under a high heat

for a long period of time. Under heat, bonding takes place between the porous aggregate

particles and once cooled the powder has bonded to form a solid piece.

Sintering can be considered to proceed in three stages. During the first, neck growth

proceeds rapidly but powder particles remain discrete. During the second, most

densification occurs, the structure recrystallizes and particles diffuse into each other.

During the third, isolated pores tend to become spheroidal and densification continues at

a much lower rate. The words Solid State in Solid State Sintering simply refer to the state

the material is in when it bonds, solid meaning the material was not turned molten to

bond together as alloys are formed.

One recently developed technique for high-speed sintering involves passing high

electrical current through a powder to preferentially heat the asperities. Most of the

energy serves to melt that portion of the compact where migration is desirable for

densification; comparatively little energy is absorbed by the bulk materials and forming

machinery. Naturally, this technique is not applicable to electrically insulating powders.

To allow efficient stacking of product in the furnace during sintering and prevent parts

sticking together, many manufacturers separate ware using Ceramic Powder Separator

Sheets. These sheets are available in various materials such as alumina, zirconia and

magnesia. They are also available in fine medium and coarse particle sizes. By matching

the material and particle size to the ware being sintered, surface damage and

contamination can be reduced while maximizing furnace loading

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Testing.

Dynamometers

Eddy Current (35 hp - 800 hp)

AC and DC (400 hp - 800 hp) (Transient / FTP Capable)

Engine Mapping

Component Level Testing

Environmental Condition Capability

Product Validation

Catalyst Aging (Gasoline and Diesel)

RAT-A / ARB approved catalyst aging

DPF, DOC, SCR, NAC/LNT Testing

HC and Urea Injection Development

Trans Shift Tests

Cold Start / Thermal Shock / Rapid Cool-down

Sensor Aging

Full Power train Tests

Stationary / Genset emissions and development

Hybrid systems testing

Fuel Cell Testing

Hot Testing / "End of Line" Audit Tests

Hundreds of available Analog & Digital Channels per test stand

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Customer Specific Data Formats

Remote Communications

Emissions (Gasoline and Diesel)

18" Horiba 4000 SCFM Full Dilution Tunnels

Partial Flow Dilution Tunnels (mini-dilution tunnels)

Double or Single Dilution

(70mm filter & 47mm filter for 2007 regulations)

MKS & Horiba FTIR Analyzers

Up to 23 Unregulated Emissions

Pre or Post Catalyst Measurement

Horiba MEXA Analytical Benches

Horiba Micro-Bench Analyzer

AVL Micro-Soot 483 and AVL Smoke Meters

Class 6 Clean Room / Filter Weighing (2007 CFR compliant)

Facilities

23,000 sq ft (Building 1)

25,000 sq ft (Building 2)

45,000-gallon total underground fuel storage

3 gasoline, 2 diesel fuels available

Fuel measurement (+/- 0.5%) in all cells

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Component Testing

Misc Tests

Fan Clutch Testing

One-Way-Clutch Alternator Pulley Cycle Tests

NVH measurement and data analysis

"Stretchy" Belt Durability Tests

"Stretchy" Belt Temp vs. Tension Studies

Component Aging / Durability

Power Steering Cold Start Torque Tests

Cylinder Head Motoring Tests

Idler Durability

Tensioner Damping Studies

Belt Tracking Studies

Vehicle Instrumentation

Dedicated Test Stands

Idler Durability

Dynamic Belt Friction

Belt Misalignment

Parasitic Loss

Bearing Noise/ Durability

Deceleration Testing

Environmental Capabilities

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Engine Lift Eye Drop Test

Hydrothermal Oven Aging (Catalyst Aging)

Electronics Support

In-House Data Acquisition & Control

Custom Hardware/Software Integration

Custom PC Based Software Application Programming

Electronic Circuit Board Design & Manufacturing

Alternative Fuel Testing

CNG and CNG Conversion Certification

Propane and Propane Conversion Certification

Ethanol Certification

Bi-Fuel (CNG + Gasoline, or Propane + Gasoline) Certification

Bio-Diesel

Hot Testing

Testing took another step in providing full service to our valued customers in the area of

high volume production hot testing. Today, we have supported dozens of engine

platforms and tested over 250 thousand engines while supplying engine plants around the

world. Quality hot testing has become an integral part of our business, both locally and as

satellite operations, with the implementation of our portable hot test cells.

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UNIT III ENGINE AUXILIARIES

A carburetor basically consists of an open pipe, a "throat" or "barrel" through which the

air passes into the inlet manifold of the engine. The pipe is in the form of a venturi it

narrows in section and then widens again, causing the airflow to increase in speed in the

narrowest part. Below the venturi is a butterfly valve called the throttle valve — a

rotating disc that can be turned end-on to the airflow, so as to hardly restrict the flow at

all, or can be rotated so that it (almost) completely blocks the flow of air. This valve

controls the flow of air through the carburetor throat and thus the quantity of air/fuel

mixture the system will deliver, thereby regulating engine power and speed. The throttle

is connected, usually through a cable or a mechanical linkage of rods and joints or rarely

by pneumatic link, to the accelerator pedal on a car or the equivalent control on other

vehicles or equipment.

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Fuel is introduced into the air stream through small holes at the narrowest part of the

venturi. Fuel flow in response to a particular pressure drop in the venturi is adjusted by

means of precisely-calibrated orifices, referred to as jets, in the fuel path.

Venturi Types

VARIABLE VENTURI CARBURETOR

FEEDBACK CARBURETOR SYSTEM

Electronic Idle-Speed Control

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Typical EFI components

Animated cut through diagram of a typical fuel injector. Injectors

Fuel Pump

Fuel Pressure Regulator

ECM - Engine Control Module; includes a digital computer and circuitry to communicate with sensors and control outputs.

Wiring Harness

Various Sensors (Some of the sensors required are listed here.)

Crank/Cam Position: hall Effect sensor

Airflow: MAF sensor, sometimes this is inferred with a MAP sensor

Exhaust Gas Oxygen: Oxygen sensor, EGO sensor, UEGO sensor

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Radiators are heat exchangers used to transfer thermal energy from one medium to

another for the purpose of cooling and heating. The majority of radiators are constructed

to function in automobiles, buildings, and electronics. The radiator is always a source of

heat to its environment, although this may be for either the purpose of heating this

environment, or for cooling the fluid or coolant supplied to it, as for engine cooling.

From an engineering perspective, a radiator varies from an ideal black body by a factor,

ε, called the emissivity, which is a spectrum-dependent property of any material.

Commonly, a fluid thermal mass, containing the heat to be rejected, is pumped from the

heat source to the radiator, where it conducts to the surface and radiates into the

surrounding cooler medium. The rate of heat flow depends on the fluid properties, flow

rate, conductance to the surface, and the surface area of the radiator. Watts per square

metre are the SI units used for radiant emittance. If the system is not limited by the heat

capacity of the fluid, or the thermal conductivity to the surface, then emittance, M is

found by a fourth-power relation to the absolute temperature at the surface. The Stefan-

Boltzmann constant is used to calculate it, as M = εσT4. Since heat may be absorbed as

well as emitted, a radiator's ability to reject heat will depend on the difference in

temperature between the surface and the surrounding environment.

Page 42: Materials 1

The axial-flow fans have blades that force air to move parallel to the shaft about which

the blades rotate. Axial fans blow air along the axis of the fan, linearly, hence their name.

This type of fan is used in a wide variety of applications, ranging from small cooling fans

for electronics to the giant fans used in wind tunnels.

Fans

Basic elements of a typical table fan include the fan blade, base, armature and lead wires,

motor, blade guard, motor housing, oscillator gearbox, and oscillator shaft. The oscillator

is a mechanism that moves the fan from side to side. The axle comes out on both ends of

the motor, one end of the axle is attached to the blade and the other is attached to the

oscillator gearbox. The motor case joins to the gearbox to contain the rotor and stator.

The oscillator shaft combines to the weighted base and the gearbox. A motor housing

covers the oscillator mechanism. The blade guard joins to the motor case for safety.

In automobiles, a mechanical fan provides engine cooling and prevents the engine from

overheating by blowing or sucking air through a coolant-filled radiator. It can be driven

with a belt and pulley off the engine's crankshaft or an electric fan switched on or off by a

thermostatic switch.

Page 43: Materials 1

Coolant pumps

Thermosysphon cooling system of 1937, without circulating pump Radiators first used

downward vertical flow, driven solely by a thermosyphon effect. Coolant is heated in the

engine, becoming less dense and so rising, cooled, denser coolant in the radiator falling in

turn. This effect is sufficient for low-power stationary engines, but inadequate for all but

the earliest automobiles. A common fallacy is to assume that a greater vertical separation

between engine and radiator can increase the thermosyphon effect. Once the hot and cold

headers are separated sufficiently to reach their equilibrium temperatures though, any

further separation merely increases pipe work length and flow restriction.All automobiles

for many years have used centrifugal pumps to circulate their coolant, driven by geared

drives or more commonly by a belt drive.

IGNITION SYSTEM

PRIMARY IGNITION SYSTEM

The primary system consists of the ignition switch, coil primary windings, distributor

contact points, condensor, ignition resistor, and starter relay.

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Ignition Switch. First, it turns on the car's electrical system so that all accessories can be

operated. It does so by providing power to the fuse panel (for those components that are

controlled by the switch. Some items are independent of the ignition switch, such as

headlights, horn, clock, etc.)  When you insert the key and turn the switch to the

"accessories" position, you are turning on the other devices in the car, such as the radio,

heater, power windows, seats, defroster, etc.

Second, in the run position, everything is turned on, plus the engine's electrical

components that enable it to run. Most important, it turns on the entire primary ignition

system. Wait a minute! We just learned that the starter takes enormous current from the

battery through its thick cable. How can the ignition switch carry so much current if there

isn't a battery cable connected to it?

The ignition switch doesn't carry the necessary current to the starter. It sends a small

current to a special device called a Relay that, in turn, allows the starter to crank. We'll

discuss that later in this article. Back to the primary ignition system...

The next component is the coil's primary winding. Inside the coil are two sets of wound

wire, comprising of the primary and secondary windings. The primary windings carry

battery voltage through and create a large magnetic field inside the coil (this is discussed

thoroughly in the section on secondary windings). Although the coil's primary windings

receive voltage from the ignition switch, they are actually turned on and off by the

distributor's contact points.

The contact points are opened and closed by a cam on the distributor's main shaft. As it

spins the cam's lobes move the actuator outward, disengaging the contacts. When the lobe

passes, the contacts close, turning on the coil primary windings. The amount of time the

points remain closed is referred to as dwell, and is an important factor in engine tuning.

Attached to the points is a condensor, an electrical device (capacitor) that limits current

flow through the points to increase their life. The condensor is necessary because the

points are opening and closing rapidly, and as they do so the voltage/current is

interrupted. This causes an arc, or spark, between the contact points. Over time, this

Page 45: Materials 1

arcing will erode the material on the points and deposit carbon, and eventually the points

will not pass current. The condensor acts as a current-absorber to limit the amount of

arcing as the points open and close.

The next component is the ignition resistor. It is necessary because ignition coils are

designed to step up battery voltage high enough - and fast enough - to keep the engine

running at high rpm. That means that, as designed, the coil would produce too much high

voltage at low rpm and heat up. Automakers long ago realized that there were two

solutions to the problem: using two coils (one for low rpm and one for high) or an

ignition resistor. Obviously, the resistor approach is the least expensive and most reliable,

so that's what they did. The resistor used varies is resistance as a function of temperature,

and limits the voltage to the coil accordingly. As the engine revs up the resistance lowers,

allowing more voltage to the coil for fast running, and the reverse happens when the

engine slows down. At idle, for instance, only about 7 volts is going through the coil

primary windings.

The only time the resistor is out of the circuit is during startup, when the engine needs all

the spark it can get. It's bypassed in the ignition switch's start position so that, during

starting, the coil gets full battery voltage. Ignition resistors can take many forms,

depending upon the manufacturer of the vehicle. Some builders mounted a big resistor on

the firewall and some others utilized a special type of wire (resistance wire) running from

the ignition switch to the coil. Still others used coils that were built with an internal

resistor. None of these is any better an approach than the others, but it's important to

know which type you have, and that you have one!

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SECONDARY IGNITION SYSTEM

The secondary ignition system consists of the coil secondary windings, distributor cap,

rotor, plug wires and spark plugs.

Coil Secondary Windings

So just how does a coil work? Well, the principle of Inductance is the answer. Physics

tells us that if you put a certain voltage through a wire (the primary) that has another wire

wrapped around it, the second (hence, secondary) wire will receive an "induced" voltage

from the first. Furthermore, the "induced" voltage is a function of the number of turns of

wire wrapped around, so if you have two coils wrapped around the wire you'll get twice

the voltage, and so on.  Voltage can be stepped-up and stepped-down using inductance.

Transformers are inductance devices, so a coil is a transformer.

Automotive coils generally have secondary-to-primary ratios of 200 to 1. Therefore, a 12-

volt input to a coil's primary windings will result in a 24,000-volt output from the

secondary winding. That's where the spark plugs get their electricity.

Inductance isn't perpetual motion, nor is it "free energy." There are many "howevers" and

other considerations to worry about. The biggest one is the coil's inability to hold the

induced voltage once it's been built up. In a very short time the voltage will "bleed of,"

leading to weak spark. Also, the coil takes a finite amount of time to build the charge up.

That's the dwell time, normally defined as the degrees of rotation of the camshaft

during which the points are closed. Too little dwell and the coil doesn't have time to

charge up fully. Too much dwell and the coil has bled off some charge, causing a weak

spark. Hesitation, low power, misfiring, pinging and a number of other conditions are

symptoms of incorrect dwell.

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UNIT IV COMPUTER INTEGRATED MANUFACTURING

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CAM Management Solutions’ Integrated Strategic Planning and Performance Management Solution is developed on the following framework as we believe a monitoring system should facilitate:

Full integration of strategic, business, service and annual planning

Implementation & management of a conceptual framework which links to

Sustainability and partnerships

Performance management that is linked to planned outcomes

Integration of policy and governance into all planning levels

Integration of the community into the corporate planning process

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CIM NETWORKING

Virtual corporations, enterprise re-engineering, and adaptive/agile manufacturing are

all new concepts based on the accomplishments of integrated manufacturing of the past

decade. The new manufacturing enterprises are characterized by ability to effect

flexible reconfiguration of resources, shorter cycle times and quick response to

customer demands. Information is a key factor in transcending physical barriers and

imparting the enterprise-oriented agility and adaptiveness to organizations. To this end,

a theory-based reference model for information integration is needed in manufacturing

enterprises. Employs the paradigm of parallel formulation as the reference model and

demonstrates how it is used to guide the planning for information integration. The

model provides both a detailed data and task analysis of manufacturing functions and

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their interactions, and guidelines for regrouping tasks into parallel processes and

thereby achieving a high level of global integration. Describes a case study of the

model, conducted on the existing CIM model at Rensselaer to evaluate and reformulate

the previous processes. The results show a better design featuring concurrent execution

of functions which in turn support agility and adaptiveness.

CNC Machine Programming

The major manufacturing steps involved in making sheet metal enclosures are sheet

shearing, hole punching and press brake folding. All these steps are done on computer

controlled CNC machines. So CNC programming is a crucial step in making high quality

products.

The first step is to convert a sheet metal enclosure design into flat patterns as if the part

was unfolded.

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The next step is to determine bend allowances and offsets for their particular machines.

With these numbers, we can program the various pieces of equipment to minimize waste

and provide the accuracy you require.

For small quantities of parts, the majority of the cost is in programming and setup. The

price curve for any quantity over 25 parts flattens out as the programming is spread out

over more and more parts.

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UNIT V QUALITY AND TESTING

Indian Standards

Bureau of Indian Standards (BIS) Publications

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Quality Management

Quality Management standards that are not covered in ISO 9001/14001 Standards are given here.

S.No. BIS Number Title

1 IS/ISO 10019: 2005

Guidelines for the Selection of Quality Management System Consultants and use of their Services (800 Kb)

2 IS/ISO/TS 16949: 2002

Quality Management Systems - Particular requirements for the application of ISO 9001:2000 for Automotive Production and relevant Service part Organisations (2.4 Mb)

3 lS/lSO/lEC 20000-1: 2005

Information Technology - Service Management Part-1 Specification (1.0 Mb)

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Computer aided engine testing

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Metrology for manufacturing Engine Components

Dimensional Metrology

In general, there will be errors of size in any machined work piece. This means that the

actual dimension will be different from nominal dimension. These errors should be

within certain given limits by tolerances and determined by the dimensional measurement

to guarantee the product quality. The dimensional measurement includes:

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Post-process Dimensional Measurement

Block Gauge

Micrometer

Profile Projector

Coordinate Measurement Machine (CMM)

On-process Dimensional Measurement

Mechanical Methods

Optical Methods

Pneumatic Methods

Ultrasonic Methods

Post-process Measurement

Traditionally, measurements have been made after the part has been produced. It is called

the post-process measurement. The post-process measurement can be used to high

production run of smaller parts. The inspection process can be made by traditional

methods. If the dimensions are not within the given tolerance zone, a correction can be

made to the next part through the machine tool.

Block Gauge

Gauge blocks are Individual Square, rectangular, or round metal blocks of various sizes.

Their surfaces are lapped and are flat and parallel within a range of 1-5 micro inch. Gage

blocks are available in sets of various sizes. The blocks can be assembled in many

combinations to obtain desired lengths. The gage block assemblies are used as an

accurate reference length to measure the part's length.

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Micrometer

The micrometer is commonly used for measuring the thickness and inside or

outside diameters of parts. Micrometers are also available for measuring depths.

Micrometers can be equipped with digital readout to reduce errors in reading.

Profile Projector

The profile projector is used for measuring two-dimensional contours of precision

specimens and other work pieces produced. The part to be measured is magnified

by an optical system and projected on a screen. The reading on the screen gives

the dimension of the part. The following is the photo of a profile projector.

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Coordinate Measurement Machine (CMM)

A coordinate measurement machine (CMM) is an advanced, multi-purpose

quality control system used to help inspection keep pace with modern production

requirements. It replaces long, complex and inefficient conventional inspection

methods with simple procedures. A CMM provides instant measurement results

without complicated setup and operating procedures. It combines surface plate,

micrometer and vernier type inspection methods into one easy to use machine.

CMM can check the dimensional and geometric accuracy of everything from

small engine blocks, to sheet metal parts, to circuit boards.

A CMM consists essentially of a probe supported on three mutually perpendicular

(X, Y & Z) axes. Each axis has a built-in reference standard.

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Procedure for simple measurements on a CMM includes:

Calibration of the probe system.

Define datum(s) on the work piece.

Perform measurement(s).

Compute the required dimensions from measurements made in Step 3.

Assess conformance to specification.

On-process Dimensional Measurement

When the manufactured parts are big, with higher material cost and longer cycle times,

on-process measurement is required to improve the productivity and reduce the cost. In

the on-process measurement, parts are measured while they are on the machine tool.

The existing on-process measurement methods can be divided into direct and indirect

methods according to the measurement principle.

Direct methods.  In direct method, the dimension of the work piece is directly measured

using an adequate instrument, while the work piece is located on the machine tool.

Therefore, the effects of tool wear distortions and machine errors can be taken into

account.

Indirect methods. The work piece accuracy can also be indirectly evaluated from radius

measurements, by monitoring the motions of the carriage, carrying the cutting tool or by

noting the position of the tip of the cutting tool.

The on-process measurement can be implemented by several methods. Here are several

on-process dimensional measurement methods:

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Mechanical Methods

Caliper Type

A typical caliper type contact gauge consists of a simple scissors caliper with non rotating

circular contact pads. The instrument can be set to measure over a range of diameters.

The contact pads or jaws are in continual rubbing contact with the work piece. It is

attached to the machine bed on its own slide so that it can be rapidly withdrawn and

returned to the measuring position in a repeatable manner. The rear gap of the scissors is

bridged by sensing element, which can be a pneumatic or electrical transducer. The

caliper is set with respect to a circular setting master. it is possible to derive an electrical

signal with both types of transducer, which can be used to control the machining process

such as grinding and turning. The measured work piece diameter range with this method

reaches 5-190mm and repeatably is 0.5 um.

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Friction Roller Type

This method measures the perimeter of the work piece by counting the number of

revolutions of the measuring roller for one or more complete revolution of the work piece

as illustrated in the following figure. The application of this method is restricted to rigid

work piece, due to the high pressure applied by the roller. This technique has been used

in turning and grinding.

Probe Type  

A probe in mechanical contact with the work piece is used to determine the actual size of

work piece. For the gauging process, the probe is moved towards the work piece and

deflected by the contact. The coordinate value of the point of the touch makes it possible

to determine the work piece radius provided the position of the axis of rotation is known.

Optical Methods

An optical method of on-process measurement is defined as one in which the transmitter

module produces and emits a light, which is collected and photo electrically sensed

through the object to be measured, by a receiver module. This produces the signals which

can be converted into a convenient form and displayed as dimensional information. The

principal advantages of optical methods are

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Direct mechanical contact between the sensor and the object to be measured is not

required.

The distance from the object to be measured to the sensor can be large.

The response time is limited only to the electronics used in the sensor.

The light variations can be directly converted into electrical signals.

The main optical on-process measurement methods include:

 

Scanning Light Beam

This technique uses laser beams for the measurement process. It employs transmitted

module which emits a high speed scanning laser beam, generally by means of a

combination of a mirror and a synchronous motor. The object to be measured interrupts

this beam, and produces a time dependent shadow. This shadow is electrically detected

by a receiver, and converted into dimensional readings by a control unit.

 

Machine Vision

The method uses a light source and the image of the work piece can be focused on the

measuring grid on the face of a television tube or CCD (Charge coupled device). Then

the diameter of the work piece is computed in terms of the image parameters, such as the

image application factor, focal distance and the image length on CDD.

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Some other optical methods exist. For example,

Light gauging

Light focusing

Light-spot detection

Light sectioning

Pneumatic Methods

This method measures a pressure drop in the gap between the air gauge and work piece,

and converts it into an electrical signal. A schematic diagram of pneumatic method is

shown as the following.

Ultrasonic Methods

In this method, ultrasound travels to the work piece, then reflects back to the transducer

which also acts as a receiver. The transit time depends on the variation from the specified

distance between work surface and transducer. By determining the transit time, the

distance can be calculated.