UNIT-III

POWER PLANTS
A steam power plant, also known as a steam power plant , is a facility designed to generate
electricity through the use of steam as the primary working fluid. It operates based on the
principles of thermodynamics, utilizing the conversion of heat energy into mechanical work
and subsequently into electrical energy.
The power plants are classified based on the type of primary energy resource used. Those
are
(i)Steam power plant (ii) Diesel power plant (iii) Hydro power plant (iv) Nuclear power
plant

STEAM POWER PLANT:

Components:
A steam power plant consists of a boiler, steam turbine and generator, condenser, feed
water, coal hopper, pulveriser and chimney. The steam power plant layout is as shown in
the following figure.

Boiler: The boiler is responsible for heating water to generate steam. This is typically
achieved by burning fossil fuels (such as coal, oil, or natural gas) or by using nuclear energy.
The generated steam is at high pressure and temperature.

Turbine: The high-pressure steam from the boilers is directed into a turbine. The turbine is
designed with blades that are turned by the force of the steam’s high-speed flow. As the
steam flows through the turbine, its high-pressure energy is converted into rotational
mechanical energy.
Generator: The turbine is connected to a generator, which consists of coils of wire within a
magnetic field. As the turbine spins, it turns the rotor of the generator, creating a moving
magnetic field. This movement induces an electric current in the wire coils, ultimately
producing electrical energy.
Condenser: After passing through the turbine, the steam is directed to the condenser. Here,
the steam is cooled and condensed back into water, releasing its latent heat. This process
allows for the efficient reuse of the water in the boiler, reducing water consumption and
increasing overall efficiency.
Cooling System: Steam power plants require a cooling system to dissipate excess heat from
the condenser. This can involve cooling water from nearby water bodies, cooling towers, or
other heat exchange methods.
Coal Hopper: The primary source of steam power plant is coal. This is stored in the hopper
and supplied to the furnace through pulveriser.
Pulveriser: The main function of pulveriser is to convert bigger size coals into smaller once,
so that the surface area of the coal increases and thereby increasing the combustion of coal in
the furnace.
Chimney: The exhaust from the furnace will be sent out through chimney. The height of
chimney will be more so that the hot dust particles will not fall on the nearby houses and
human beings.

Working Principle:
The steam generated in the boiler will be expanded in the turbine, thereby generation of
mechanical energy. Further this mechanical energy is converted in to electricity in the
generator. The expanded steam will be condensed in the condenser and pumped back to
boiler for further use.

Advantages
Generation of power is continuous.
Initial cost low compared to hydel plant.
Less space required.
This can be located near the load centre so that the transmission losses are reduced.
It can respond to rapidly changing loads.
Disadvantages
Long time required for installation.
Transportation and handling of fuels major difficulty.
 Efficiency of plant is less.
Power generation cost is high compared to hydel power plant.
Maintenance cost is high.

DIESEL POWER PLANTS

Working Principle: In a diesel power plant, diesel engine is used as the prime mover. The
diesel burns inside the engine and the products of this combustion act as the working fluid to
produce mechanical energy. The diesel engine drives alternator which converts mechanical
energy into electrical energy.
Diesel power plants produce power from a diesel engine. Diesel electric plants in the range of 2
to 50 MW capacities are used as central stations for small electric supply networks and used as a
standby to hydroelectric or thermal plants where continuous power supply is needed.
The diesel power plants are cheaply used in the fields mentioned below.
 Mobile electric plants
 Standby units
 Emergency power plants
 Starting stations of existing plants
 Central power station etc.

LAYOUT OF DIESEL POWER PLANT:

Figure shows the arrangements of the engine and its auxiliaries in a diesel power plant.
The major components of the diesel power plant are:
Engine
Engine is the heart of a diesel power plant. Engine is directly connected through a gear box to
the generator. Generally two-stroke engines are used for power generation. Now a days,
advanced super & turbo charged high speed engines are available for power production.
Air supply system
Air inlet is arranged outside the engine room. Air from the atmosphere is filtered by air filter
and conveyed to the inlet manifold of engine. In large plants supercharger/turbocharger is
used for increasing the pressure of input air which increases the power output.
Exhaust System
This includes the silencers and connecting ducts. The heat content of the exhaust gas is
utilized in a turbine in a turbocharger to compress the air input to the engine.
Fuel System
Fuel is stored in a tank from where it flows to the fuel pump through a filter. Fuel is injected
to the engine as per the load requirement.
Cooling system
This system includes water circulating pumps, cooling towers, water filter etc. Cooling water
is circulated through the engine block to keep the temperature of the engine in the safe range.
Lubricating system
Lubrication system includes the air pumps, oil tanks, filters, coolers and pipe lines. Lubricant
is given to reduce friction of moving parts and reduce the wear and tear of the engine parts.
Starting System
There are three commonly used starting systems, they are;
 A petrol driven auxiliary engine
 Use of electric motors.
 Use of compressed air from an air compressor at a pressure of 20 Kg/cm.

Governing system
The function of a governing system is to maintain the speed of the engine constant
irrespective of load on the plant. This is done by varying fuel supply to the engine
according to load.
 Advantages
Diesel power plants can be quickly installed and commissioned.
Quick starting.
Requires minimum labour.
Plant is smaller, operate at high efficiency and simple compared to steam power plant.
It can be located near to load centres.
Disadvantages
Capacity of plant is low.
Fuel, repair and maintenance cost are high.
Life of plant is low compared to steam power plant.
Lubrication costs are very high.
Not guaranteed for operation under continuous overloads.
Noise is a serious problem in diesel power plant.
Diesel power plant cannot be constructed for large scale.

HYDRO ELECTRIC POWER PLANT:

Working Principle:
Hydroelectric power plants convert the hydraulic potential energy from water into electrical
energy. Such plants are suitable where water with suitable head is available.

LAYOUT OF HYDEL POWER PLANT:

Dam
Dams are structures built over rivers to stop the water flow and form a reservoir. The reservoir
stores the water flowing down the river. This water is diverted to turbines in power stations. The
dams collect water during the rainy season and store it, thus allowing for a steady flow through
the turbines throughout the year.

Dams are also used for controlling floods and irrigation. The dams should be water-tight and
should be able to withstand the pressure exerted by the water on it. There are different types of
dams such as arch dams, gravity dams and buttress dams. The height of water in the dam is called
head race.
Spillway
A spillway as the name suggests could be called as a way for spilling of water from dams. It is
used to provide for the release of flood water from a dam. It is used to prevent over toping of the
dams which could result in damage or failure of dams. Spillways could be controlled type or
uncontrolled type. The uncontrolled types start releasing water upon water rising above a
particular level. But in case of the controlled type, regulation of flow is possible.

Penstock and Tunnels

Penstocks are pipes which carry water from the reservoir to the turbines inside power station.
They are usually made of steel and are equipped with gate systems. Water under high pressure
flows through the penstock. A tunnel serves the same purpose as a penstock. It is used when an
obstruction is present between the dam and power station such as a mountain.
Surge Tank
Surge tanks are tanks connected to the water conductor system. It serves the purpose of reducing
water hammering in pipes which can cause damage to pipes. The sudden surges of water in
penstock is taken by the surge tank, and when the water requirements increase, it supplies the
collected water thereby regulating water flow and pressure inside the penstock.
Power Station
Power station contains a turbine coupled to a generator. The water brought to the power station
rotates the vanes of the turbine producing torque and rotation of turbine shaft. This rotational
torque is transferred to the generator and is converted into electricity.
The used water is released through the tail race. The difference between head race and tail race is
called gross head and by subtracting the frictional losses we get the net head available to the
turbine for generation of electricity.
Advantages
Water the working fluid is natural and available plenty.
Life of the plant is very long.
Running cost and maintenance are very low.
Highly reliable.
Running cost is low.
Maintenance and operation costs are very less.
No fuel transport problem.
No ash disposal problem.
Disadvantages
Initial cost of plant is very high.
Power generation depends on quantity of water available which depends on rainfall.
Transmission losses are very high.
More time is required for erection.

Nuclear Energy
Nuclear energy is the energy trapped inside each atom.
Heavy atoms are unstable and undergo nuclear

Nuclear reactions are of two types,

1. Nuclear fission…the splitting of heavy nucleus

2. Nuclear fusion…the joining of lighter nuclei

Fission:
Fission may be defined as the process of splitting an atomic nucleus into fission
fragments.
The fission fragments are generally in the form of smaller atomic nuclei and neutrons.
Large amounts of energy are produced by the fission process.
 NUCLEAR POWER PLANTS

Working Principle: Nuclear power plants convert the energy released from the nucleus of an
atom, typically via nuclear fission.
Nuclear power is the use of sustained or controlled nuclear fission to generate heat and do
useful work. Nuclear Electric Plants, Nuclear Ships and Submarines use controlled nuclear
energy to heat water and produce steam.
Nuclear power provides about 6% of the world's energy and 13–14% of the world's
electricity. Also, more than 150 naval vessels using nuclear propulsion have been built.
LAYOUT OF NUCLEAR POWER PLANT:

NUCLEAR REACTOR

A nuclear reactor is an apparatus in which heat is produced due to nuclear fission chain
reaction.
Fig. shows the various parts of reactor, which are as follows:
 Nuclear Fuel
 Moderator
 Control Rods
 Reflector
 Reactors Vessel
 Biological Shielding
 Coolant
Nuclear Fuel
Fuel of a nuclear reactor should be fissionable material which can be defined as an element or
isotope whose nuclei can be caused to undergo nuclear fission by nuclear bombardment and to
produce a fission chain reaction. It can be one or all of the following U233, U235 and Pu239.
Natural uranium found in earth crust contains three isotopes namely U234, U235 and U238 and their
average percentage is as follows:
U238 - 99.3% U235 - 0.7% and U234 - Trace
Moderator
In the chain reaction the neutrons produced are fast moving neutrons. These fast moving
neutrons are far less effective in causing the fission of U235 and try to escape from the
reactor. To improve the utilization of these neutrons their speed is reduced. It is done by
colliding them with the nuclei of other material which is lighter, does not capture the neutrons
but scatters them. Each such collision causes loss of energy, and the speed of the fast moving
neutrons is reduced. Such material is called Moderator. The slow neutrons (Thermal
Neutrons) so produced are easily captured by the nuclear fuel and the chain reaction proceeds
smoothly. Graphite, heavy water and beryllium are generally used as moderator
Control Rods
The Control and operation of a nuclear reactor is quite different from a fossil fuelled (coal or oil
fired) furnace. The energy produced in the reactor due to fission of nuclear fuel during chain
reaction is so much that if it is not controlled properly the entire core and surrounding structure
may melt and radioactive fission products may come out of the reactor thus making it
uninhabitable. This implies that we should have some means to control the power of reactor. This
is done by means of control rods.
Control rods in the cylindrical or sheet form are made of boron or cadmium. These rods can be
moved in and out of the holes in the reactor core assembly. Their insertion absorbs more neutrons
and damps down the reaction and their withdrawal absorbs less neutrons. Thus power of reaction
is controlled by shifting control rods which may be done manually or automatically.
Reflector
The neutrons produced during the fission process will be partly absorbed by the fuel rods,
moderator, coolant or structural material etc. Neutrons left unabsorbed will try to leave the
reactor core never to return to it and will be lost. Such losses should be minimized. It is done by
surrounding the reactor core by a material called reflector which will send the neutrons back into
the core. The returned neutrons can then cause more fission and improve the neutrons economy
of' the reactor. Generally the reflector is made up of graphite and beryllium.
Reactor Vessel
It is a. strong walled container housing the cure of the power reactor. It contains moderator,
reflector, thermal shielding and control rods.
Biological Shielding
Shielding the radioactive zones in the reactor roan possible radiation hazard is essential to protect,
the operating men from the harmful effects. During fission of nuclear fuel, alpha particles, beta
particles, deadly gamma rays and neutrons are produced. Out of these gamma rays are of main
significance. A protection must be provided against them. Thick layers of lead or concrete are
provided round the reactor for stopping the gamma rays. Thick layers of metals or plastics are
sufficient to stop the alpha and beta particles.
Coolant
Coolant flows through and around the reactor core. It is used to transfer the large amount of heat
produced in the reactor due to fission of the nuclear fuel during chain reaction. The coolant either
transfers its heat to another medium or if the coolant used is water it takes up the heat and gets
converted into steam in the reactor which is directly sent to the turbine.
Advantages
Need less space.
Fuel consumption is small, hence transportation and storage charges are low.
Well suited for large power demands.
Less work men required.
Disadvantages
Capital cost very high.
Radioactive wastes, if not disposed properly have adverse effect on environment.
Maintenance cost high.
 MECHANICAL POWER TRANSMISSION
Mechanical Power transmitting refers to transfer mechanical energy from one component
to another machine. Ex: Electric shavers, Water Pumps, Turbines

Types of Power Transmission:

(i) Belt drives (ii) Chain drives (iii) Rope drives (iv) Gear drives

Belt Drives:

Belts are used to transmit power from one shaft to another shaft by means of pulleys which
rotate at same speed or at different speeds. These drives transmit power to either small or
long distances.
These belt drives are majorly classified into Open belt drive and Cross belt drives.
Open Belt drive: This is used when the shafts should rotate in the same direction, and when
the shafts are arranged in parallel. As shown in figure below, A is called Driving pulley and
B is called Followers/ Driven pulley.

Cross belt drive: In this, the rotation of pulleys is in opposite direction. this is due to the belt
is crossed one. In this, the driver pulls the belt from one side and delivers it to another side.

Applications: Washing machines, Automobile, Flour mills, lathes, milling machines,

drilling machines, paper mills and Conveyors.

MERITS:
 Low component cost & high efficiency
 Transmits power to long distance
 Smoother and quitter operation
  Absorbs shocks and vibrations
 Light weight and relatively durable
 Low maintainace cost
DEMERITS:
 Belt slippage can vary the velocity ratio
 Finite speed range
 Heavy loads on the bearings and shafts

CHAIN DRIVE:

Chain drive is a type of mechanical power transmission system that uses chains to transfer
power from one place to another. A conventional chain drive consists of two or more
sprockets and the chain itself. The holes in the chain links fit over the sprocket teeth.

The chain drive consists of three elements – driving sprocket/ Larger Sprocket, driven
sprocket / Smaller Sprocket, and endless chain wrapped around the sprocket.

Applications: Chain drive used in bicycle, motorbike, printing machine, textile machine,
etc.
Advantages of Chain drive:
 Positive drive as there is no slip, hence a constant velocity ratio.
 Occupies less space compared to belt drive.
 Life is more compared to the belt drive.
 Used for large centre distance.
 Transmission efficiency is larger than the belt drive.

Disadvantages Of Chain Drive:

 Noisy compared to belt drive.
  Initial cost is higher compared to belt drive.
 Adjustment in the centre distance is necessary.
 Maintenance cost.
 Higher & complex compared to belt drive.

ROPE DRIVE:
When the centre distance between the driver and driven shaft is very large and higher
power is required to be transmitted, rope drives are used. Here instead of a belt, wire rope is
used. Appropriate size and number of grooves are provided on the pulley rim.

Advantages of Rope Drive:

 Large power can be transmitted by using no. of ropes.
 Easy and simple maintenance.
 Silent drive.
 Because of wedging action due to groove, the higher coefficient of friction.
 Due to flexibility in the rope little misalignment in the drive is permissible.

Disadvantages of Rope Drive:

 Power loss due to slip.

 Occupies larger space.
 Constant speed ratio cannot be maintained.
 Adjustment in the centre distance is always necessary.
 Wear rates for the wire rope pulleys is higher.
 The initial cost is relatively higher.

Applications: Elevator / lift, overhead crane, hoist, ropeway, etc.

GEAR DRIVE:
Gear drives is used, when centre to centre distance between driver shafts and driven shafts
is very small.
Definition of Gears:
A gear is a rotating machine part having cut teeth. Toothed wheels can transmit
power and motion from one shaft to another shaft by means of successive engagement of
teeth.
Both the gears which are engaged will rotate in opposite direction. Power
transmission capacity depends on the friction between surfaces of two discs.
Gear drive consists of two wheels, The smaller wheel called as Pinion and the
larger wheel called as Gear.
It gives exact and uniform velocity ratio, due to this ability of maximum power
transmission and exact velocity ratio, gear drive is called as perfect positive drive.

Gears can be made from metals such as steel or brass, or from plastics such as
nylon or polycarbonate.
Advantages of Gear Drive:
 Positive drive and has more efficiency than belt and rope drive.
 The operation of the drive is simple and effective.
 Life is more compared to other drives.
 With one input speed, no. of output speeds can be obtained drive.
 Safe and compact.
 Constant velocity ration is obtained.

Disadvantages of Gear Drive:

 If the tooth geometry of the gear is not properly maintained, drive may get locked.
 Not preferred when very high-speed transmission is required.
 If the lubrication arrangement is not provided, it may produce noise.
Applications of gear drives: Automotive transmission systems, wheel differentials, marine
equipment, turbines, and gear motors.

Difference between Belt Drives, Chain Drives, and Gear Drives

S.
Particulars Belt drive Chain drive Gear drive
No.

1. Main element Pulleys, belt Sprockets, chain Gears

No slip No slip
2. Slip Slip may occurs
(Positive drive) (Positive drive)
For large centre For moderate For short centre
3. Suitability
distance centre distance distance

4. Space requires Large Moderate Less

For low velocity For moderate For high velocity

5. Use
ratio velocity ratio ratio
6. Design,
manufacturing, Simplest Simplest Complicated
complexity
7. Life Less Moderate Long
Installation
8. Less Moderate More
cost
Failure of gear
Failure of belt Failure of chain
may cause
does not cause the may not
9. Failure serious break
further damage of seriously damage
down in the
machine. the machine.
machine
Requires proper
10. Lubrication Not required Required
lubrication
 INTRODUCTION TO ROBOTICS
JOINTS & LINKS, CONFIGURATIONS, AND APPLICATIONS OF ROBOTICS

Introduction to Robotics:
The Robot Institute of America (1969) defines robot as a re-programmable, multifunctional
manipulator designed to move materials, parts, tools or specialized devices through various
programmed motions for the performance of a variety of tasks.
Industrial robots are mechanical devices that are programmable. They are used to replace
human as they can perform repetitive works or dangerous works with extreme accuracy.
These robots are capable of working in three or more directions.
Need of Robots:
 Robots are superior to human in terms of strength, size, speed and accuracy etc.
 Robots are better than human in performing repetitive tasks with better quality and
consistency
 Robots don’t have limitations and negative attributes like fatigue, diversion of
attention,
 Robots doesn’t expects rest
 Can save work and time
 Can work in adverse conditions also
 They assists in material handling systems
 Can expect faster inspection and testing.
Asimov’s laws
Laws of robotics are the set of laws, rules, or principles, which are intended as a
fundamental framework to underpin the behaviour of robots designed to have a degree
of autonomy.
The three laws of Robotics or Asimov’s laws are set of rules derived by the science friction
author Isac Asimov. The Three Laws are:
 A Robot should not injure Human
 A Robot must obey the orders given by human except where such orders would
conflict with the First law
 A Robot must protect its own existence as long as such protection doesn’t conflict
with the first or second law.
ROBOT ANATOMY:
Robot anatomy deals with the study of different joints and links and other aspects of the
manipulator's physical construction. A robotic joint provides relative motion between two
links of the robot. Each joint, or axis, provides a certain degree-of-freedom (DOF) of
motion.
The anatomy of robot is also known as structure of robot. The basic components or
sections in anatomy of robots are as follows.
The Anatomy of Industrial Robots deals with the assembling of outer components of a
robot such as wrist, arm, and body.
Some of the key facts about robot anatomy.

Fig 1.1 Robot Anatomy

 End Effectors: A hand of a robot is considered as end effectors. The grippers and
tools are the two significant types of end effectors. The grippers are used to pick
and place an object, while the tools are used to carry out operations like spray
painting, spot welding, etc. on a work piece.
 Robot Joints: The joints in an industrial robot are helpful to perform sliding and
rotating movements of a component.
 Manipulator: The manipulators in a robot are developed by the integration of links
and joints. In the body and arm, it is applied for moving the tools in the work
volume. It is also used in the wrist to adjust the tools.
 Kinematics: It concerns with the assembling of robot links and joints. It is also used
to illustrate the robot motions.
Joints and Links:
The manipulator of an industrial robot consists of a series of joints and links. Robot anatomy
deals with the study of different joints and links and other aspects of the manipulator's
physical construction. A robotic joint provides relative motion between two links of the
robot. Each joint, or axis, provides a certain degree-of-freedom (dof) of motion.

In most of the cases, only one degree-of- freedom is associated with each joint. Therefore the
robot's complexity can be classified according tothe total number of degrees-of-freedom they
possess. Each joint is connected to two links, an input link and an output link. Joint provides
controlled relative movement between the input link and output link.

A robotic link is the rigid component of the robot manipulator. Most of the robots are
mounted upon a stationary base, such as the floor. From this base, a joint-link numbering
scheme may be recognized as shown in Figure 1.1. The robotic base and its connection to the
first joint are termed as link-0. The first joint in the sequence is joint-1. Link-0 is the input
link for joint-1, while the output link from joint-1 is link-1 which leads to joint-2. Thus link 1
is, simultaneously, the output link for joint-1 and the input link for joint-2. This joint-link-
numbering scheme is further followed for all joints and links in the robotic systems.

Nearly all industrial robots have mechanical joints that can be classified into following five
types as shown in Figure
a) 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 being parallel.

b) Orthogonal joint (type U joint) This is also a translational sliding motion, but the input
and output links are perpendicular to each other during the movement.
c) 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 links.

d) Twisting joint (type T joint) This joint also involves rotary motion, but the axis or rotation
is parallel to the axes of the two links.
e) Revolving joint (type V-joint, V from the “v” in revolving) in this type, axis of input link
is parallel to the axis of rotation of the joint. However the axis of the output link is
perpendicular to the axis of rotation.

Configurations: or coordinates
Co-ordinate systems:- Industrial robots are available in a wide variety of sizes, shapes, and
physical configurations. The vast majority of today’s commercially available robots possess
one of the basic configurations:
1. Polar configuration
2. Cylindrical configuration
3. Cartesian coordinate configurable
4. Jointed-arm configuration

Polar configuration:-

The polar configuration is pictured in part (a) of Fig.

It uses a telescoping arm that can be raised or
lowered about a horizontal pivot The pivot is
mounted on a mta6ng base These various joints
provide the robot with the capability to move its arm
within a spherical space, and hence the name
“spherical coordinate” robot is sometimes applied to
this type. A number of commercial robots possess the
polar configuration
Cylindrical configuration:-
The cylindrical configurable, as shown in fig, uses a
vertical column and a slide that can be moved up or
down along the column. The robot arm is attached to
the slide so that it cm he moved radially with respect
to the column. By routing the column, the robot is
capable of achieving a work space that approximation
a cylinder.

Cartesian coordinate configurable:-

The cartesian coordinate robot, illustrated in part Cc)
of Fig, uses three perpendicular slides to construct the
x, y, and z axes. Other names are sometimes applied
W this configuration, including xyz robot and
rectilinear robot, By moving the three slides relative
to one another, the robot is capable of operating
within a rectangular work envelope.

Jointed-arm configuration:-
The jointed-arm robot is pictured in Fig. Its
configuration is similar to that of the human arm. It
consists of two straight components. Corresponding
to the human forearm and upper arm, mounted on a
vertical pedestal. These components are connected by
two rotary joints corresponding to the shoulder and
elbow.
Advantages:
Increased Efficiency: Robots can work 24/7 without getting tired, leading to increased
productivity and efficiency.
Improved Accuracy: Robots are capable of performing tasks with high precision and
accuracy, reducing errors and improving quality.
Increased Safety: Robots can perform tasks that are dangerous for humans, improving
overall safety in the workplace.
Reduced Labor Costs: The use of robots can lead to reduced labor costs, as robots can
perform tasks more cheaply than human workers.
Increased profitability: By increasing the efficiency in the production process, reducing
the resource and time needed to complete it, and also achieving higher quality products,
industrial robots can achieve higher profitability levels with lower cost per product.
Longer working hours: People distracted after some time and their working pace
becomes slow. But a robot will work 24/7, and keeps running at 100%.

Disadvantages:
Initial Cost: Implementing and maintaining a robotics system can be expensive, especially
for small and medium-sized businesses.
Job Losses: The increased use of robots may result in job losses for human workers,
particularly in industries where manual labor is prevalent.
Limited Capabilities: Robots are still limited in their capabilities compared to human
workers and may not be able to perform tasks requiring dexterity or creativity.
Maintenance Costs: Robots require regular maintenance and repair, which can be time-
consuming and expensive.
Applications of robot are:
 1. Arc Welding
One of the driving forces for switching to robot welding is improving the safety of workers
from arc burn and inhaling hazardous fumes.
 2. Spot Welding
Spot welding joins two contacting metal surfaces by directing a large current through the
spot, which melts the metal and forms the weld delivered to the spot in a very short time
 3. Materials Handling
Material handling robots are utilized to move, pack and transferring of parts from one
piece of equipment to another This reduces the direct labour costs are reduced and much of
the tedious and hazardous activities traditionally performed by human labour are
eliminated.
 4. Machine Tending
Robotic automation for machine tending is the process of loading and unloading raw
materials into machinery for processing and overseeing the machine while it does a job.
 5. Painting
Robotic painting is used in automotive production and many other industries as it increases
the quality and consistency of the product. Cost savings are also realized through less
rework.
 6. Picking, Packing and Palletizing
Most products are handled multiple times prior to final shipping. Robotic picking and
packaging increases speed and accuracy along with lowering production costs.
 7. Assembly
Robots routinely assemble products, eliminating tedious and tiresome tasks. Robots increase
output and reduce operational costs.
 8.Mechanical Cutting, Grinding, Deburring and Polishing:
Building dexterity into robots provides a manufacturing option that is otherwise very difficult
to automate. An example of this is the production of orthopedic implants, such as knee and
hip joints. Buffing and polishing a hip joint by hand can normally take 45-90 minutes while a
robot can perform the same function in just a few minutes.