Esc mech notes.pdf

MODULE-1
SOURCES OF ENERGY
ENERGY RESOURCES
Energy Resources: energy is defined as the capacity to do work. it is primary
requirement for day to day activities of human beings.
ENERGY- Capacity to do work
 Most of the energy that we use is mainly derived from conventional energy
sources.
 Due to the vast demand of energy, the rate of depletion of these resources has
reached alarmingly low levels.
 This situation has directed us to seek alternate energy sources such as solar,
wind, ocean, biomass, Hydel etc.

ENERGY SOURCES
Energy that comes from outer space is called CELESTIAL or INCOME
energy.
The CAPITAL energy sources are mainly, fossil fuels, nuclear fuels and
heat traps.
CELESTIAL ENERGY SOURCES ARE- Electromagnetic, gravitational
and particle energy from stars, planets, moon etc.
The energy existing in the earth is known as CAPITAL energy.
ELECTROMAGNETIC ENERGY of the earth‟s sun is called DIRECT
SOLAR ENERGY. This results in WIND, HYDEL, GEOTHERMAL,
BIOFUEL, etc.
GRAVITATIONAL ENERGY of earth‟s moon produces TIDALENERGY.

Different sources of energy:
The sources of energy are classified in the following
two ways:
(a) Conventional and non- conventional sources of energy
(b) Renewable and non-renewable sources of energy

RENEWABLE SOURCES OF ENERGY
Energy sources which are continuously produced in nature and are essentially
inexhaustible are called renewable energy sources.
1. Direct solar energy 2. Wind energy
3. Tidal energy 4. Hydel energy
5. Ocean thermal energy 6. Bio energy
7. Geo thermal energy 8. Peat
9. Fuel wood 10. Fuel cells
11. Solid wastes 12. Hydrogen
NON-RENEWABLE ENERGY SOURCES
Energy sources which have been accumulated over the ages and not quickly
replenish able when they are exhausted.
1. Fossil fuels.
2. Nuclear fuels.
3. Heat traps.

Conventional sources of energy Non- conventional sources of energy
These are widely used and economical These are rarely used and initial cost is high
Most of them are exhaustible Most of them are in-exhaustible
Most of them are pollute the environment Most of them are environment friendly
They are reliable (continuous supply of energy
is possible)
They are not reliable (continuous supply of
energy is not possible)
Energy transmission cost is high Energy transmission cost is low
Example: Fossil fuels, Hydel energy Example: solar, wind, tidal etc.
Difference between Conventional and non- conventional sources of energy:

Renewable sources of energy Non- Renewable sources of energy
These are in-exhaustible These are exhaustible
Freely available and environment friendly Not freely available & hazardous to
environment
Initial cost is high but maintenance cost is
low
Initial cost is low but maintenance cost is
high
Energy concentration varies from region to
region
Energy concentration almost same in all
region
Example: solar, hydel, wind, tidal etc. Example: Fossil fuels, nuclear fuels.
Difference between Renewable and non-renewable sources of energy:

HYDRO POWER PLANTS
In hydroelectric power plants the potential energy of water due to its high location is
converted into electrical energy. The total power generation capacity of the hydroelectric
power plants depends on the head of water and volume of water flowing towards the water
turbine.

The hydroelectric power plant, also called as dam or hydro power plant, is used
for generation of electricity from water on large scale basis. The dam is built
across the large river that has sufficient quantity of water throughout the river. In
certain cases where the river is very large, more than one dam can built across the
river at different locations. The rain water flowing as river can be stored behind
dams and released in a regulated way to generate hydro power.
https://www.youtube.com/watch?v=OC8Lbyeyh-E
https://www.youtube.com/watch?v=W0axSL4tQYA

WATER TURBINES
A water turbine is a hydraulic prime mover that converts the energy of falling
water into mechanical energy in the form of rotation of shaft. The mechanical
energy in turn is converted into electrical energy by means of an electric generator.
Water turbines are classified based on the following factors:
Type of energy available at the inlet of the turbine:
(a) Impulse turbine: The energy available at the inlet of the turbine is only kinetic
energy.
Example: Pelton wheel, Girad turbine, Banki turbine, etc.
(b) Reaction turbine: Both pressure energy and kinetic energy is available at the
inlet of the turbine.
Example: Kaplan turbine, Francis turbine, Thomson turbine, etc.
Based on the head under which turbine works:
a) High head turbine: Head of water available at the inlet of the turbine ie, above
300 m. Example: Pelton wheel.
b) Medium head turbine: Head of water available at the inlet of the turbine
ranges from 50m to 150 m. Example: Francis turbine.
c) Low head turbine: Head of water at the inlet will be less than 50m. Example:
Kaplan Turbine

1) PELTON WHEEL TURBINE
Pelton wheel is a tangential flow impulse turbine, used for high heads and small
quantity of water flow. Figure shows the schematic diagram of a Pelton wheel.
The Pelton wheel consists of the following parts: nozzle with spear head, shaft,
rotor, buckets, casing, and tailrace.
https://www.youtube.com/wat
ch?v=5F7XwjUgK8o –
Hoover Dam

2) FRANCIS TURBINE
Francis turbine is a mixed flow reaction turbine used for medium heads. It was
the first Hydraulic turbine with radial flow, designed by American scientist James
Francis. Figure shows the front and top views of a Francis turbine.
https://www.youtube.com/watc
h?v=3BCiFeykRzo – Lesics
h?v=skQNf5_61Ps – SaVree
h?v=-9e4MdQsG1w

3) KAPLAN TURBINE
The Kaplan turbine is a low head reaction turbine in which water flows axially,
Figure shows the rotor and front view of a Kaplan turbine. Kaplan turbine
consists of the following parts: guide vanes, runner vanes, shaft, spiral casing,
tailrace, hub, and blade.
https://www.youtube.com/watch?
v=0p03UTgpnDU – Lesics
v=_eLufvzh5HU
v=k0BLOKEZ3KU – comparison

SOLAR ENERGY
Solar radiation is radiant energy emitted by the sun from a nuclear fusion
reaction that creates electromagnetic energy. The spectrum of solar radiation is
close to that of a black body with a temperature of about 5800 K. About half of
the radiation is in the visible shortwave part of the electromagnetic spectrum.
Video - https://www.youtube.com/watch?v=L_q6LRgKpTw – Solar cells

How a Photovoltaic Cell Works –
A photovoltaic cell is made of semiconductor materials that absorb the photons emitted by
the sun and generate a flow of electrons. Photons are elementary particles that carry solar
radiation at a speed of 300,000 kilometers per second. In the 1920s, Albert Einstein
referred to them as “grains of light”. When the photons strike a semiconductor material
like silicon , they release the electrons from its atoms, leaving behind a vacant space. The
stray electrons move around randomly looking for another “hole” to fill.
To produce an electric current, however, the electrons need to flow in the same direction.
This is achieved using two types of silicon. The silicon layer that is exposed to the sun is
doped with atoms of phosphorus, which has one more electron than silicon, while the other
side is doped with atoms of boron , which has one less electron. The resulting sandwich
works much like a battery: the layer that has surplus electrons becomes the negative
terminal (n) and the side that has a deficit of electrons becomes the positive terminal
(p). An electric field is created at the junction between the two layers.
When the electrons are excited by the photons, they are swept to the n-side by an electric
field, while the holes drift to the p-side. The electrons and holes are directed to the
electrical contacts applied to both sides before flowing to the external circuit in the form of
electrical energy. This produces direct current. An anti-reflective coating is added to the
top of the cell to minimize photon loss due to surface reflection.

WIND ENERGY
Wind energy is the energy contained in the force of the winds blowing
across the earth surface. Wind energy is defined as the kinetic energy
associated with the movement of large masses of air over the earth‟s
surface.
https://www.youtube.com/watch?v=xy9nj94xvKA

WORKING
The circulation of the air in the atmosphere is caused by the non-uniform heating
of the earth‟s surface by the sun. The air immediately above warm area expands
and becomes less dense. It is then forced upwards by a cool denser air which
flows in from the surrounding areas causing wind.
Video: https://www.youtube.com/watch?v=qSWm_nprfqE

NUCLEAR ENERGY
Nuclear energy is the energy that holds the nucleus of an atom. The energy
released during nuclear fission or fusion, especially when used to generate
electricity.
Nuclear Fission: - Nuclear fission is the process of splitting a nucleus into
two nuclei with smaller masses. Fission means “to divide”.
“The most common nuclear fuels are 235U. Not all nuclear fuels are
used in fission chain reactions”
Chain Reaction: - A chain reaction is an ongoing series of fission
reactions. Billions of reactions occur each second in a chain reaction.
 On earth, nuclear fission reactions take place in nuclear reactors, which
use controlled chain reactions to generate electricity.
 Uncontrolled chain reactions take place during the explosion of an
atomic bomb.

https://www.youtube.com/watch?v=ke1L4An1yP8
https://www.youtube.com/watch?v=_UwexvaCMWA

Nuclear energy is the energy released during nuclear fission or fusion,
especially when used to generate electricity. Nuclear fuel is any material that
can be consumed to derive nuclear energy.
The most common type of nuclear fuel is fissile elements that can be made to
undergo nuclear fission chain reactions in a nuclear reactor. The most common
nuclear fuels are 235U and 239Pu.
The basic nuclear generating station energy cycle is shown in Figure. Fuel
containing fissile material (Uranium) is fed to the reactor where fission takes
place. The energy liberated appears in the form of heat, which is used to boil
water in Heat exchanger or steam generator.
The steam produced from the boiling water spins a turbine-generator set,
where the heat is converted first to kinetic energy and then it will converts to
mechanical energy in the turbine and to electricity by the generator.

FOSSIL FUELS: https://www.youtube.com/watch?v=BYpfOKwlYS8
Fuel is a substance which, when burnt, i.e. on coming in contact and reacting with
oxygen or air, produces heat. Thus, the substances classified as fuel must necessarily
contain one or several of the combustible elements: carbon, hydrogen, sulphur, etc.
In the process of combustion, the chemical energy of fuel is converted into heat
energy.
1. Solid Fuels:
Solid fuels are mainly classified into two categories:
Natural fuels: wood, coal, etc.
Manufactured fuels: charcoal, coke, briquettes, etc.
Wood:
The most commonly used and easily obtainable solid fuel is wood. It is the oldest
type of fuel which man had used for centuries after the discovery of the fire itself.
Charcoal is an artificial fuel obtained from wood.
Coal:
Coal is a combustible black or brownish-black sedimentary rock usually occurring
in rock strata in layers or veins called coal beds or coal seams.. The major chemical
elements in coal are: carbon, hydrogen and oxygen.
There are two types of coals: i) Bituminous coal ii) Anthracite coal.

Charcoal:
Charcoal is a produce derived from destructive distillation of wood, being left in the
shape of solid residue. Charcoal burns rapidly with a clear flame, producing no smoke
and developing heat of about 6050 cal/kg.
Coke:
It is obtained from destructive distillation of coal, being left in the shape of solid residue.
Coke can be classified into two categories: soft coke and hard coke. Soft coke is obtained
as the solid residue from the destructive distillation of coal in the temperature range of
600-650oC. It contains 5 to 10% volatile matter. It burns without smoke. It is extensively
used as domestic fuel. Hard coke is obtained as solid residue from the destructive
distillation of coal in the temperature range of 1200-1400oC. It burns with smoke and is a
useful fuel for metallurgical process.
Advantages of solid fuels:
They are easy to transport.
They are convenient to store without any risk of spontaneous explosion.
Their cost of production is low.
They possess moderate ignition temperature.
Disadvantages of solid fuels:
Their ash content is high.
Their large proportion of heat is wasted.
Their combustion operation cannot be controlled easily.
Their cost of handling is high.

2. Liquid fuels:
Liquid fuels include Gasoline, Diesel oil, Kerosene, Heavy oil, Naptha, Lubricating oils,
etc. These are obtained mostly by fractional distillation of crude petroleum or liquefaction
of coal.
Gasoline or Petrol:
The straight run gasoline is obtained either from distillation of crude petroleum or by
synthesis. It contains some undesirable unsaturated straight chain hydrocarbons and sulphur
compounds. It has boiling range of 40-120oC.
Diesel Fuel:
The diesel fuel or gas oil is obtained between 250-320oC during the fractional distillation of
crude petroleum. This oil generally contains 85% C. 12% H. Its calorific value is
about11000 kcal/kg.
The suitability of a diesel fuel is determined by its cetane value. Diesel fuels consist of
longer hydrocarbons and have low values of ash, sediment, water and sulphalt contents.
Kerosene Oil:
Kerosene oil is obtained between 180-250oC during fractional distillation of crude
petroleum. It is used as an illuminant, jet engine fuel, tractor fuel, and for preparing
laboratory gas. With the development of jet engine, kerosene has become a material of far
greater importance than it is used to be. When kerosene is used in domestic appliances, it is
always vaporized before combustion. By using a fair excess of air it burns with a smokeless
blue flame.

Advantages of liquid fuels:
 They possess higher calorific value per unit mass than solid fuels.
 They burn without dust, ash, clinkers, etc.
 They are easy to transport through pipes.
 They can be stored indefinitely without any loss.
 They are clean in use and economic to handle.
 They require less excess air for complete combustion.
 They require less furnace space for combustion.
Disadvantages of liquid fuels:
 The cost of liquid fuel is relatively much higher as compared to solid fuel.
 Costly special storage tanks are required for storing liquid fuels.
 There is a greater risk of five hazards, particularly, in case of highly inflammable
and volatile liquid fuels.
 For efficient burning of liquid fuels, specially constructed burners and spraying
apparatus are required.

3. Gaseous fuels:
Gaseous fuels occur in nature, besides being manufactured from solid and liquid fuels.
Natural Gas:
Natural gas is generally associated with petroleum deposits and is obtained from wells
dug in the oil-bearing regions. The approximate composition of natural gas is :
CH4 = 70.9%, C2H6 = 5.10%, H2 = 3%, CO + CO2 = 22%
Producer Gas:
Producer gas is essentially a mixture of combustible gases carbon monoxide and
hydrogen associated with non-combustible gases N2, CO2, etc. It is prepared by passing
air mixed with little steam (about 0.35 kg/kg of coal) over a red hot coal or coke bed
maintained at about 1100oC in a special reactor called gas producer. It consists of a steel
vessel about 3 m in diameter and 4 m in height. The vessel is lined inside with fire
bricks. It is provided with a cup and cone feeder at the top and a side opening for the
exit of producer gas. At the base it has an inlet for passing air and steam. The producer
at the base is also provided with an exit for the ash formed.

Advantages of gaseous fuels:
 They can be conveyed easily through pipelines to the actual place of need,
thereby eliminating manual labour in transportation.
 They can be lighted at ease.
 They have high heat contents and hence help us in having higher temperatures.
 They can be pre-heated by the heat of hot waste gases, thereby affecting
economy in heat.
 Their combustion can readily by controlled for change in demand like
oxidizing or reducing atmosphere, length flame, temperature, etc.
 They do not require any special burner.
 They are free from impurities found in solid and liquid fuels.
Disadvantages gaseous fuels:
 Very large storage tanks are needed.
 They are highly inflammable, so chances of fire hazards in their use is high.

Combustion and Combustion products:
The term combustion refers to the exothermal oxidation of a fuel, by air or
oxygen occurring at a sufficiently rapid rate to produce a high temperature, usually with
the appearance of a flame.
As most of the fuels contain carbon or carbon and hydrogen, the combustion
involves the oxidation of carbon to carbon dioxide and hydrogen to water. Sulphur, if
present, is oxidised to sulphur dioxide while the mineral matter forms the ash. Complex
fuels like coal undergo thermal decomposition during combustion to give simpler products
which are then oxidised to carbon dioxide, water etc.
e.g.: Coke on combustion gives carbon dioxide
Coal → Coke + Coal gas
C (coke) + O2 → CO2
Calorific Value of a Fuel:
The calorific value of a fuel is defined as the quantity of heat liberated by the complete
combustion of unit weight of the fuel in air or oxygen, with subsequent cooling of the
products of combustion to the initial temperature of the fuel.
It is expressed in kJ/kg
The calorific value of a fuel depends upon the nature of the fuel and the relative
proportions of the elements present, increasing with increasing amounts of hydrogen.
Moisture if present considerably reduces the calorific value of a fuel. The calorific value
may be theoretically calculated from the chemical composition of the fuel.

BIOFUELS
Introduction: - Biomass is biological material derived from living, or recently living
organisms. It most often refers to plants or plant-derived materials which are specifically
called lignocelluloses. As an energy source, biomass can either be used directly via
combustion to produce heat, or Indirectly after converting it to various forms of biofuel.
This biomass may be transformed by physical, chemical and biological processes to
biofuels. In chemical forms biomass is stored solar energy and can be converted into
solid, liquid and gaseous energy carries.
Biomass is biological/organic material derived from living, or recently living organisms.
(The term is equally applicable to both animal and vegetable derived material, but in the
context of energy, it refers to plant based material) The term „Biofuel‟ refers to liquid or
gaseous fuels for the transport sector that are predominantly produced from biomass.
A variety of fuels can be produced from biomass resources including liquid fuels, such as
ethanol, methanol, biodiesel, Fischer- Tropsch diesel, and gaseous fuels, such as hydrogen
and methane.
The biomass resource base for biofuel production is composed of a wide variety of
forestry and agricultural resources, industrial processing residues, and municipal solid and
urban wood residues.

Bio fuels are liquid fuels produced from biological materials or biomass, Such as
sugarcane fiber, corn, cellulose or vegetable oils, agricultual residues, sewage and other
wastes.
It is a renewable source of energy emitting less than fossil fuels and as such considered
as an alternative to the constantly and rapidly diminishing fossil fuels. the following are
the different types of wires fuels used in various engineering application
Fuel pellets, made from wood chips, sawdust or agricultural waste area few solid form
of biofuels, but are not so popular in view of their higher environmental pollution
potential. they are used for combustion in coal fired power plant.
Biodiesel a form of liquid biofuel is produced from non edible oil seeds. The oils
obtained from seeds of several plants and trees like pongamia (honge), neem
(Bevu),hippe hit, simarouba, red physic nut(kadharalu), can be used as an alternative
fuel for Diesel or blended with diesel to petrol auto motor vehicles like bus, lorry,
tractor etc and also generators and industrial machines that run on diesel engine
biodiesel also so used as an heating fuel in commercial boiler

Biodiesel:
It is produced from oils or fats using transesterification and is a liquid similar in composition to
fossil/mineral diesel. Chemically, it consists mostly of fatty acid methyl (or ethyl) esters (FAMEs).
Feedstocks for biodiesel include animal fats, vegetable oils, soy, rapeseed, jatropha, mahua,
mustard, flax, sunflower, palm oil, hemp, field pennycress, Pongamia pinnata and algae. Pure
biodiesel (B100) currently reduces emissions with up to 60% compared to diesel
Advantages of biodiesel fuel:
• An excessive production of soybeans in the world makes it an economic way to utilize this surplus
for manufacturing the Biodiesel fuel.
• One of the main biodiesel fuel advantages is that it is less polluting than petroleum diesel.
• The lack of sulfur in 100% biodiesel extends the life of catalytic converters.
• Another of the advantages of biodiesel fuel is that it can also be blended with other energy
resources and oil.
• It can also be distributed through existing diesel fuel pumps, which is another biodiesel fuel
advantage over other alternative fuels.
• The lubricating property of the biodiesel may lengthen the lifetime of engines.
Disadvantages of biodiesel fuel:
• At present, Biodiesel fuel is about one and a half times more expensive than petroleum diesel fuel.
• It requires energy to produce biodiesel fuel from soy crops; plaus there is the energy of sowing,
fertilizing and harvesting.
• As Biodiesel cleans the dirt from the engine, this dirt can then get collected in the fuel filter, thus
clogging it. So, filters have to be changed after the first several hours of biodiesel use.
• Biodiesel fuel distribution infrastructure needs improvement, which is another of the biodiesel
fuel disadvantages.

Bio fuels
• Fuels which are derived from Biomass are called biofuels.
Biomass is an organic matter produce by plants(Both in
land & water)
• Biofuel energy is indirect source of solar energy, because
sunlight is utilised in growing plants by photosynthesis
• Biofuel is defined as any fuel whose energy is obtained by
process called as biological carbon fixation
Note:carbon Fixation is the process that converts inorganic
carbon(CO2) into organic compounds (starch, cellulose) this
process occurs in living organisms hence it is called as
biological carbon fixation
• Biomass biomass or organic matter includes sugarcane,
Non wood plants corn, forest crops, grasses, aquatic crops,
algae and in directed land crop (animal and human waste)

Followingfigureshows Ablockdiagramof biomass energytransformation
Bioconversionprocess
organic matter
Plants thatcontainsstordenegy
Photo
synthesis
biomass
Requiredform
ofenergy(or)
biofuelcanbe
produced
Solar
energy

Why biofuel?
• After search in oil prices international market as
focus attention on liquid by face particularly
countries with any dependency on oil import.
• Energy security and climate change are driving
the development of biofuels globally .
• it is called as an alternative fuels.

Some of the common biofuels are
(Biodiesel, bio ethanol, methanol, biogas)
1. Biodiesel (consisting of long chain alkyl Esters)
• Biodiesel some vegetable oils edible as well as non edible oils in the
user in its pure farm [B100] or blended with petroleum diesel can
be used in compression ignition engine.
• Flash point greater than and more than 130 degree Celsius
• Compression ratio is 21:1
• Made by chemically reacting lipids( oily organic compounds) with
an alcohal producing fatty acid esters .
Advantages
• 1. Simple to use, high cetane rating and eating it is safe.
• 2. Biodegradable, produces less air pollutants than diesel.
• 3. Non toxic and essential free from sulphur and aromatics.
• 4. Can be blended with diesel at any concentration.
• Example: jatropha and karanja are most processing biodiesel
resources also rapeseed soybean oil, animal fat, sunflower oil, palm
oil, coconut etc.

2.Bio ethanol
• Bio ethanol (ethyl alcohol/ drinking alcohol)
• Ethanol(C2H5OH) is a colourless liquid biofuel.
• Boiling point is 78 degree Celsius.
• Can be derived from with Biomass containing
sugars(sugarcane, sugar beat) starches, By
fermentation process.
• Ethanol can be used as a fuel with petrol.
• Flash point is 16.6 degree Celsius to 25 degree
Celsius.

3. Methanol
• used Limited basis to fuel internal combustion
engines
• Cellulose containing organic matter like wood is
more suitable for producing methanol in large
scale
• It is a byproduct of distillation of
wood(decomposition of wood by heating to a
temperature of 450 degrees celsius to 500
degree Celsius in the absence of air)

4. Biogas
• Biogas is produced by biochemical conversion
process
• Organic waste from plants, animals and humans
can be used to produce biogas.
• Biogas contains
50 to 60 percentage of Methane
30 to 40 percentage of CO2
5 to 10 percentage of H2
0.5 to 0.7 percentage of N2
• Uses for cooking, lighting, heating etc..

Ozone Layer Definition
“The ozone layer is a region in the earth’s
stratosphere that contains high concentrations
of ozone and protects the earth from the
harmful ultraviolet radiations of the sun.”

Causes of Ozone Layer Depletion
The ozone layer depletion is a major concern and is associated with a number of factors. The main
causes responsible for the depletion of the ozone layer are listed below:
Chlorofluorocarbons
Chlorofluorocarbons or CFCs are the main cause of ozone layer depletion. These are released by
solvents, spray aerosols, refrigerators, air-conditioners, etc.
The molecules of chlorofluorocarbons in the stratosphere are broken down by the ultraviolet
radiations and release chlorine atoms. These atoms react with ozone and destroy it.
Unregulated Rocket Launches
Researches say that the unregulated launching of rockets result in much more depletion of ozone
layer than the CFCs do. If not controlled, this might result in a huge loss of the ozone layer by the
year 2050.
Nitrogenous Compounds
The nitrogenous compounds such as NO2, NO, N2O are highly responsible for the depletion of
the ozone layer.
Natural Causes
The ozone layer has been found to be depleted by certain natural processes such as Sun-spots and
stratospheric winds. But it does not cause more than 1-2% of the ozone layer depletion.
The volcanic eruptions are also responsible for the depletion of the ozone layer.

Effects Of Ozone Layer Depletion
The depletion of the ozone layer has harmful effects on the environment. Let us
see the major effects of ozone layer depletion on man and environment.
Effects on Human Health
The humans will be directly exposed to the harmful ultraviolet radiations of the
sun due to the depletion of the ozone layer. This might result in serious health
issues among humans, such as skin diseases, cancer, sunburns, cataract, quick
ageing and an weakend immune system.
Effects on Animals
Direct exposure to ultraviolet radiations leads to skin and eye cancer in animals.
Effects on the Environment
Strong ultraviolet rays may lead to minimal growth, flowering and
photosynthesis in plants. The forests also have to bear the harmful effects of the
ultraviolet rays.
Effects on Marine Life
Planktons are greatly affected by the exposure to harmful ultraviolet rays. These
are higher in the aquatic food chain. If the planktons are destroyed, the organisms
present in the lower food chain are also affected.

Following are some points that would help in preventing this
problem at a global level:
1. Avoid Using Pesticides
Natural methods should be implemented to get rid of pests and
weeds instead of using chemicals. One can use eco-friendly
chemicals to remove the pests or remove the weeds manually.
2.Minimize the Use of Vehicles:
The vehicles emit a large amount of greenhouse gases that lead to
global warming as well as ozone depletion. Therefore, the use of
vehicles should be minimized as much as possible.
3.Use Eco-friendly Cleaning Products:
Most of the cleaning products have chlorine and bromine releasing
chemicals that find a way into the atmosphere and affect the ozone
layer. These should be substituted with natural products to protect
the environment.
4.Use of Nitrous Oxide should be Prohibited

• The sun is the largest source of renewable
energy and this energy is abundantly available
in all parts of the earth.
• It is in fact one of the best alternatives to the
non-renewable sources of energy.
• One way to tap solar energy is through the use
of solar ponds. Solar ponds are large-scale
energy collectors with integral heat storage for
supplying thermal energy.
• It can be use for various applications, such as
process heating, water desalination,
refrigeration, drying and power generation.

• The solar pond works on a very simple principle. It is
well-known that water or air is heated they become
lighter and rise upward e.g. a hot air balloon.
• Similarly, in an ordinary pond, the sun’s rays heat the
water and the heated water from within the pond rises
and reaches the top but loses the heat into the
atmosphere.
• The net result is that the pond water remains at the
atmospheric temperature.
• The solar pond restricts this tendency by dissolving salt
in the bottom layer of the pond making it too heavy to
rise.

Module - 2
LATHE
LATHE MACHINE: A lathe is a machine tool which turns cylindrical material,
touches a cutting tool to it, and cuts the material. It is said to be the mother of all
the machine tools. The lathe is the oldest of all machine tools and the most basic
tool used in industries. A lathe is defined as a machine tool is primarily used to
produce circular objects and is used to remove excess material by forcing a
cutting tool against a rotating work piece.
WORKING PRINCIPLE OF LATHE:
A lathe, basically a turning machine works on the principle that a cutting tool can
remove material in the form of chips from the rotating work pieces to produce
circular objects.

LATHE OPERATIONS
1.Turning, 2. Taper turning, 3. Thread cutting, 4. Facing, 5. Knurling
Turning: - The principle of a metal cutting operation using a single-point tool on
a lathe. The work piece is supported in between the two centers which
permit the rotation of the work piece.

Facing: - Facing is defined as an operation performed on the lathe to generate
either flat surfaced or shoulders at the end of the work piece. In facing operation,
the direction of feed given is perpendicular to the axis of the lathe.
Knurling: - Knurling is defined as an operation performed on the lathe to
generate serrated surfaces on work pieces by using a special tool called knurling
tool which impresses its pattern on the work piece.

Thread Cutting :- A thread is a helical ridge formed on a cylindrical or conical
rod. It is cut on a lathe when a tool ground to the shape of the thread, is moved
longitudinally with uniform linear motion while the work piece is rotating with
uniform speed.
Taper turning: - Taper is defined as a uniform increase or decrease in diameter of
a piece of work measured along its length. Taper turning is an operation on a lathe
to produce conical surface on the work pieces.

Methods of Taper Turning: -
1) Taper Turning by setting over the tail Stock.
2) Taper Turning by swivelling the Compound Rest (Tool Post).
This method of taper turning shown in Fig. It is more suitable for work pieces,
which require steep taper for short lengths. The compound tool rest is swivelled to
the required taper angle and then locked in the angular position. The carriage is
also locked at that position. For taper turning, the compound tool rest is moved
linearly at an angle so that the cutting tool produces the tapered surface on the
work piece. This method is limited to short tapered lengths due to the limited
movement of the compound tool rest.

Milling
Milling: -Milling is a manufacturing process in which the excess material from the
work piece is removed by a rotating multipoint cutting tool called milling cutter.
The milling cutter is a multipoint cutting tool. The work piece is mounted on a
movable work table which will be fed against the revolving milling cutter to perform
the cutting operation.
MILLING MACHINE: - A milling machine is a power operated machine tool in
which the work piece is mounted on moving table is machined to various shapes
when moved under a slow revolving serrated cutter.
PRINCIPLE OF MILLING

Classification of Milling Machines -

End milling: -End milling is a process of milling that is used to mill slots,
pockets and keyways in such a way that the axis of the milling cutter is
perpendicular to the surface of the work piece. The milling operation when used
for keyway cutting as shown in figure. The advantage of the end milling operation
is that we can achieve depth of cut of nearly of the diameter of the mill.

Classification of Drilling Machines -

https://www.youtube.com/watch?v=f2nbjRVJa88 – Drilling Operations
Drilling Machine

Advanced Manufacturing Systems
Advanced manufacturing refers to the new innovative technologies, processes,
methods for producing the desired products. While traditional manufacturing is
based on the use of dedicated plant and production lines with little or no flexibility.
A few manufacturing systems or technologies defined under advanced
manufacturing include –
1)CAD/CAM
2) Rapid prototyping
3) Industrial Robotics

Classification of Additive Manufacturing Process

ROBOTICS
An industrial robot is a” reprogrammable, Multifunctional Manipulator”
Anthropomorphic characteristics. The most obvious anthropomorphic characteristic
of an industrial robot is its mechanical arm, which is used to perform various
industrial tasks.
Robots can be substituted for humans in hazardous or uncomfortable work
environments.
A robot performs its work cycle with a consistency and repeatability that cannot
be attained by humans.
Robots can be programmed. When the production run of the current task is
completed, a robot can be reprogrammed and equipped with the necessary tooling
to perform an altogether different task.
 Robots are controlled by computers and can therefore be connected to the
computer systems to achieve computer integrated manufacturing.

ROBOT ANATOMY
The manipulator of an industrial robot consists of a series of joints and links.
Robot anatomy is concerned with the type and size of these joints and links and
other aspects of the manipulator‟s physical construction.
JOINTS AND LINKS
A joint of an industrial robot is similar to a joint in human body; it provides
relative motion between two parts of the body. Each joint, of the robot so-called
degree-of freedom (DOF) of motion.

1. Linear joint (type L joint). The relative movement between the input link and
the output link is a Translational sliding motion, with the axes of the two
links parallel.
2. Orthogonal joint (type O joint). This is also a translation sliding motion, but the
input and output links are perpendicular to each other during move.
3. Rotational joint (type R joint). This type provides rotational relative motion,
with the axis of rotation perpendicular to the axes of the input and output link.

4.Twisting joint (type T joint). This joint also involves rotary motion, but the axis
of rotation is parallel to the axes of the two links.
Classification based on ROBOT configurations:
Industrial robots are designed to have various arm manipulations so as to have
motion in different directions. The possible type of arm movements that a robot is
designed with defines configurations.
A robot can have any one the following configurations.
• Cartesian configuration
• Cylindrical configuration
• Polar configuration
• Jointed – arm configuration

1. CARTESIAN CONFIGURATION ROBOT:
Cartesian configurations robot is so called because the Arm movement of robot is
designed to move parallel to x, y, z-axis of a Cartesian coordinate system as
show in figure. A robot designed with this type of configurations Capable of
moving its arm to any point linearly within rectangular work space. Since the
arm movement in linear, the robot is also called as rectilinear or gantry robot.

2. CYLINDRICAL CONFIGURATION ROBOT:
The cylindrical configuration combines both vertical (z-axis) and horizontal (x-
axis) linear movements with rotary movement in the horizontal plane about
vertical axis (y-axis). It is also called so because its motions sweep out a partially
cylindrical working volume. This robot configuration finds application in radial
workplace layout where the work approached primarily in the horizontal plane
and where no obstructions are present.

3. POLAR CONFIGURATION OR SPHERICAL CONFIGURATION:
The geometry of the spherical or polar configuration combines rotational
movement in both horizontal and vertical planes with a single linear movement of
the arm. This configuration occupies and sweeps out a relatively large volume and
access of the arm within this total volume is restricted.

4. JOINTED – ARM CONFIGURATION ROBOT:
This robot manipulator has the general configuration of human arm. Consisting
two straight component‟s corresponding to the human forearm and upper are
mounted on a vertical pedestal that can be rotated about the base. The jointed arm
configuration shown in fig. consists of a vertical column that swivels about the
base using a T joint. At the top of the column is a shoulder joint (R joint), whose
output link connects to an elbow joint (R joint).

ADVANTAGES OF ROBOTS
Robotics and automation can, in many situation, increase productivity, safety,
efficiency, quality and consistency of product.
Robots can work in hazardous environments.
Robots need no environmental comfort.
Robots work continuously without any humanity needs and illness.
Robots have repeatable precision at all times.
Robots can be much more accurate than humans.
DISADVANTAGES OF ROBOTS
In appropriate and wrong response
A lack of decision making power
A loss of power
Damage to the robot and other devices

ROBOT APPLICATIONS
• Need to replace human labor by robot.
• Work environment hazardous for human beings.
• Repetitive task
• Boring and unpleasant task
• Multi shift operations
• Operating for long hours without rest
• Assembly applications
• Material handling applications
• Processing operations
• Inspection applications

Joining Process: Soldering, Brazing and welding
Soldering: - Soldering is a method of uniting two thin metal pieces using a
dissimilar metal or alloy by the application of heat. The alloy of lead and tin is
called soft solder, is used in varying proposition for sheet metal work, plumbing
work and electrical junctions. The melting temp of the soft solder will be
between 150 to 50 C. To clean the joint surfaces and to prevent oxidation a
suitable flux is used while soldering. Zinc chloride is the flux that is commonly
used in soft soldering. A soldering iron is used to apply the heat produced from
the electrical source. An alloy of copper, tin, and silver known as hard solder
is used for stronger joint. https://www.youtube.com/watch?v=pv-q1dDS_xQ
Method of soldering https://www.youtube.com/watch?v=GwRhUa4th2c
a. Cleaning of joining surfaces b. Application of flux
c. Tinning of surface to be soldered d. Heating
e. Final clean-up https://www.youtube.com/watch?v=lcOdZPjlGCA

Brazing:- Brazing is the method of joining two similar or dissimilar metals using a
special fusible alloy. Joints formed by brazing are stronger than that of soldering.
During the brazing, the base metal of the two pieces to be joined is not melted. The
filler metal must have ability to wet the surfaces of the base metal to which it is
applied. Some diffusion or alloying of the filler metal with base metal takes place
even though the base metal does not reach its melting temp. The materials used in
brazing are copper base and silver base alloy. These two can be classified under the
name spelter.
https://www.youtube.com/watch?v=neL4CMdUpjg
Method of brazing https://www.youtube.com/watch?v=fWF0zCcXR5A
1. Cleaning the surface of the parts.
2. Application of flux at the place of joint.
3. Common borax and mixture of borax and boric acid is used as flux.
4. The joint and the filler material are heated by gas welding torch above the melting

Welding: - Welding may be defined as the metallurgical joining of two metal
pieces together to produce essentially a single piece of metal. Welding is
extensively used in the fabrication working which metal plates, rolled steel
sections, casting of ferrous materials are joined together. It is also used for
repairing broken, worn out, or defective metal part.
https://www.youtube.com/watch?v=Nao_mLIh5dk
Principle of welding : A welding is a metallurgical process in which the junction
of the two parts to be joined are heated and then fused together with or without
the application of pressure to produce a continuity of the homogenous material of
the same composition and characteristics of the part which are being joined.
Types of welding https://www.youtube.com/watch?v=TeBX6cKKHWY
Welding are classified in to two type
• Pressure welding
• Fusion welding

In Pressure welding the parts to be joined are heated only up to the plastic state
and then fused together by applying the external pressure. Ex: forge welding,
resistance welding
In Fusion welding which also known as non-pressure is welding, joints of the two
parts are heated to the molten state and allowed to solidify.
Ex: arc welding, gas welding.
Arc welding: - The arc welding operates under the principle that when two
conductor of an electric circuit are touched together momentarily and then
instaneously separated slightly, assuming that there is sufficient voltage in the
circuit to maintain the flow of current, an electric arc is formed. Concentrated heat
is produced throughout the length of the arc at a temperature of about 5000 to
6000°C. In arc welding, usually the parts to be welded are wired as one pole of the
circuit, and the electrode held by the operator forms the other pole.

Electric Arc Welding
https://www.youtube.com/watch?v=elmDvqdeMKI

The flux coating over the electrode produces an inert gaseous shield surrounding
the arc and protects the molten metal from oxidizing by coming in contact with
atmosphere. https://www.youtube.com/watch?v=CoHVA7nr82A
https://www.youtube.com/watch?v=DIf_l8l5BkY - detailed

https://www.youtube.com/watch?v=uO5pVLOAmD4&t=5s

https://www.youtube.com/watch?v=twUAa5LWUvk
https://www.youtube.com/watch?v=jtlOOOTpZYM - analysis
https://www.youtube.com/watch?v=y-OKi8oSNQ4 - Comparison

Oxy-acetylene welding
When Right proportions of oxygen and acetylene are mixed in the welding torch
and then ignited. The flame produced is called as the oxy-acetylene flame. The
temperature attained in this welding is around 32000C hence has an ability to melt
all commercial metals.

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