Post on 14-Apr-2018
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PROJECT REPORT ON
PNEUMATIC CRANE
SUBMITTED IN PARTIAL FULLFILLMENT OF THE REQUIREMENT FOR
THE AWARD OF THE DEGREE OF
BACHELOR OF TECHNOLOGY
(MECHANICAL ENGINEERING)
PROJECT GUIDES
MR. ARUN KUMAR (ASSOT. PROF.)
MR. SATISH KUMAR (LECT.)
SUBMITTED TO:-
H.O.D. MECHANICAL ENGG. SUBMITTED BY:-
MR. N. K. BATRA SHASHI AZAD (11082484)
VIKRANT (11082459)
SHARV MOHIT (11082478)
SUMEET SHARMA (11082460)
MAHARISHI MARKANDESHWAR
ENGINEERING COLLEGE
MULLANA
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ACKNOWLEDGEMENT
The concept of Project work, being a part of the engineeringcurriculum is of great use to the students. They get an opportunity to
work and gain much practical experience and exposure while working
with the equipments in the field of project.
We consider ourselves extremely fortunate that we will get the
opportunity to gain this valuable practical knowledge during the course
of our project work and we would be enabling our potential and
innovation to bring in practical.
we express our sincere gratitude to Mr. N.K. BATRA (H.O.D.
Mechanical Engg.) and our project guides MR. ARUN KUMAR
(Assot. Prof.) & MR. SATISH KUMAR (Lecturer) for standing by
our side to guide us through the project and make our project meaningful
experience.
In this project we will show the working, basic parameters and
mainly the basic innovation we are trying to show and implement our
practical knowledge.
I also thanks for all those persons in other departments too who
provided me valuable information that I required in my project work.
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CONTENT
SR.NO TOPIC
1 INTRODUCTION
2 OBJECTIVE
3 BLOCK DIAGRAM
4 ABSTRACT
5 CLASSIFICATION
6 COMPONENTS
7 DESIGN CONSIDERATION
8 PROBLEMS
9 CONCLUSION
10 BIBILIOGRAPHY
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OBJECTIVES
1) To construct an arrangement using disc base rotation by DC gearmotor.
2) To fabricate a crane front panel with pulley arrangement that helpto rotate the string and to lift the material from the base area using
another DC gear motor.
3) To construct and install an electromagnet fitted at the stings openend at base.
4) To link both motors and electromagnet using power supply usingswitching arrangement.
5) To construct and install a cylindrical hydraulic setup to the arm at
a suitable place.
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BLOCK DIAGRAM
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ABSTRACT
Any of a diverse group of machines that not only lift heavy
objects but also shift them horizontally. Cranes are distinct from hoists,
passenger elevators, and other devices intended solely or primarily for
vertical lifting and from conveyors, which continuously lift or carry bulk
materials such as grain or coal. Cranes have come into their present
widespread application only since the introduction of steam engines,
internal-combustion engines, and electric motors, beginning in the 19th
century.
The most prominent component of that class of cranes known as
derrick cranes is the jib, or boom; this is a long beam that is structurally
reinforced so that it will not bend. The jib is supported or held aloft by
guy wires running from its top to a vertical mast, or pillar, that is itself
stiffly braced; the guy wires set the angle at which the jib leans. Along
the entire length of the jib runs a pulley system whose cables or chains
are wound and unwound around a drum, or cylinder, that is placed at the
jib's base and is turned by a motor. The cable dropping from the top of
the jib is attached to loads and lifts them vertically. The loads may also
be moved from side to side by having the jib pivot, or rotate, on its base
around the mast.
A traveling jib crane is one in which the pulley system is
suspended from a trolley, or wheeled carriage, moving along the length
of the jib.
Such traveling cranes usually have lifting capacities of from 5 to
250 tons. A potentially more powerful derrick is the floating crane,
which is built on a barge for such purposes as constructing bridges or
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salvaging sunken objects. The Musashi, a large crane of this type built in
Japan in 1974, can lift a 3,000-ton load.
Problems in maintaining stability always arise with jibcranes, and in the case of larger cranes that lift heavy loads at long
outreaches, special care has to be taken to avoid tipping of the crane. For
this purpose, besides the usual practice of mounting the hoisting
machinery in such a way as to counterpoise part of the load on the boom,
special ballast weights must be added to ensure that the crane will not be
overturned.
The cantilever crane, a type much used in the construction ofships and tall buildings, has a horizontal boom that rests upon and can
rotate about a vertical mast. The load is suspended from a trolley that
can move along a track on the boom.
During the erection of a building of many stories, the mast of
a cantilever crane may be extended upward repeatedly as the height of
the building increases.
Bridge cranes comprise another important class of cranes
in which the pulley system is suspended from a trolley that moves on
tracks along one or two horizontal beams, called the bridge, that are
supported at both ends. In most cases, the bridge itself can move along a
pair of parallel rails, so that the crane can serve a large rectangular area.
A circular space can be served by a rotary bridge crane, in which one
end of the overhead beam is supported by a central pivot while the other
end moves on a circular rail on the periphery of the area. The overhead
traveling crane, a bridge crane for which the rails are mounted above the
level of the ground or floor, has the advantage of causing no obstruction
of the working area. Overhead traveling cranes are commonly used
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indoors, where their rails can be attached to the columns that support the
roof.
If the construction of overhead rails is impracticable, the ends
of the bridge can be attached to upright towers that move on rails at theground level; such cranes are called gantry, or goliath, cranes. A
commonly used type of small movable crane is the truck crane, which is
a crane mounted on a heavy, modified truck. Such cranes frequently use
unsupported telescoping booms; these are made up of collapsible
sections that can be extended outward like the sections of an old nautical
telescope or spyglass. The extension of the boom is usually managed
hydraulically. Truck cranes make up in mobility and ease of transportwhat they lack in hoisting capacity.
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Mobile Derrick Crane
A crane lifts materials for the construction of a research
center at the South Pole in 1992. The derrick crane moves heavy objects
through the use of a motor, which winds cable around a winch, and a
system of pulleys.
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CLASSIFICATION
Any of a diverse group of machines that not only lift heavy objects
but also shift them horizontally. Cranes are distinct from hoists,
passenger elevators, and other devices intended solely or primarily for
vertical lifting and from conveyors, which continuously lift or carry bulk
materials such as grain or coal. Cranes have come into their present
widespread application only since the introduction of steam engines,
internal-combustion engines, and electric motors, beginning in the 19th
century.
The most prominent component of that class of cranes known as
derrickcranes is the jib, or boom; this is a long beam that is structurally
reinforced so that it will not bend. The jib is supported or held aloft by
guy wires running from its top to a vertical mast, or pillar, that is itself
stiffly braced; the guy wires set the angle at which the jib leans. Along
the entire length of the jib runs a pulley system whose cables or chains
are wound and unwound around a drum, or cylinder, that is placed at the
jib's base and is turned by a motor. The cable dropping from the top of
the jib is attached to loads and lifts them vertically. The loads may also
be moved from side to side by having the jib pivot, or rotate, on its base
around the mast. A simple pivoting hand-operated jib crane is depicted
in Figure 1.
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Fig: 1
A traveling jib crane is one in which the pulley system is
suspended from a trolley, or wheeled carriage, moving along the length
of the jib, as illustrated in Figure 2. Such traveling cranes usually have
lifting capacities of from 5 to 250 tons. A potentially more powerful
derrick is the floating crane, which is built on a barge for such purposes
as constructing bridges or salvaging sunken objects. The Musashi, a
large crane of this type built in Japan in 1974, can lift a 3,000-ton load.
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Fig: 2
Problems in maintaining stability always arise with jib cranes, and
in the case of larger cranes that lift heavy loads at long outreaches,
special care has to be taken to avoid tipping of the crane. For this
purpose, besides the usual practice of mounting the hoisting machinery
in such a way as to counterpoise part of the load on the boom, special
ballast weights must be added to ensure that the crane will not be
overturned.
The cantilever crane, a type much used in the construction of ships
and tall buildings, has a horizontal boom that rests upon and can rotate
about a vertical mast. The load is suspended from a trolley that can
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move along a track on the boom. A cantilever crane used in shipyards is
depicted in Figure 3. During the erection of a building of many stories,
the mast of a cantilever crane may be extended upward repeatedly as the
height of the building increases.
Fig: 3
Bridge cranes comprise another important class of cranes in which
the pulley system is suspended from a trolley that moves on tracks along
one or two horizontal beams, called the bridge, that are supported at both
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ends. In most cases, the bridge itself can move along a pair of parallel
rails, so that the crane can serve a large rectangular area. A circular
space can be served by a rotary bridge crane, in which one end of the
overhead beam is supported by a central pivot while the other end moveson a circular rail on the periphery of the area. The overhead traveling
crane, a bridge crane for which the rails are mounted above the level of
the ground or floor, has the advantage of causing no obstruction of the
working area. Overhead traveling cranes are commonly used indoors,
where their rails can be attached to the columns that support the roof.
This type of crane is depicted in Figure 4. If the construction of
overhead rails is impracticable, the ends of the bridge can be attached to
upright towers that move on rails at the ground level; such cranes are
called gantry, or goliath, cranes.
Fig: 4
A commonly used type of small movable crane is the truck crane,
which is a crane mounted on a heavy, modified truck. Such cranes
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frequently use unsupported telescoping booms; these are made up of
collapsible sections that can be extended outward like the sections of an
old nautical telescope or spyglass. The extension of the boom is usually
managed hydraulically. Truck cranes make up in mobility and ease of
transport what they lack in hoisting capacity.
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COMPONENTS
The key components of pneumatics are:
Pneumatic pump There are three versions of the pump. The old
Generation 1 pump, the new Generation 2 pump (both of these are
spring-loaded) and the small pump without a spring (designed for use
with motors). The Gen. 1 pump is red, while the Gen. 2 pump is yellow
and has a larger contact pad at the top of the pump.
Pumps are the primary source of air in a pneumatic circuit.
Pneumatic cylinder
Cylinders look like pumps, but they are the outputs of the energy, rather
than the inputs. There are five versions of cylinders. The Generation 1
cylinders came in two lengths, only had one input and thus were limited
in how they could be used. The Generation 2 cylinders have 2 inputs
(and come in studded, studless, and small versions), and allow pushing
and pulling, depending on which input air is pumped into.
Pneumatic switch
Switches have three ports on them, and a Lego axle which controls
which of the ports are connected to each other.
Switch Left Port Middle Port Right Port
Left position OpenConnected to
Right
Connected to
CenterMiddle
PositionClosed Closed Closed
Right positionConnected to
Center
Connected to
LeftOpen
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When a port is "open", that means it is like an open tire valve; all the air
will leak out as fast as it can. When a port is closed, no air can enter or
leave that port. When ports are connected, air will freely travel through
the switch between those two ports.
Pneumatic tubing
Tubing is simply the means by which air power is transferred through
the circuit. Tubing can connect to a switch, air tank, T-junction,
cylinder, pump, distribution block, or flex-hose.
Flex-hoses aren't actually considered pneumatic pieces; they were
designed as part of the Technic system for a different purpose, but fans
have discovered that pneumatic tubing actually fits over flex hoses
pretty well, so many people use them as tubing extenders whenever they
are needed. Flex hoses are more rigid than tubing.
Pneumatic tubing almost always comes with sets in an uncut form, and
are required to be cut into smaller pieces using scissors. On the 8049
technic tractor and log loader and the 8110 Unimog U400, the tubes are
already cut to size.
Pneumatic T-junction
A T-junction is a very small piece that allows three pieces of tubing to
connect into one junction, essentially splitting (or joining) airflow from
two hoses into one. These only allow 1:2 branching, but by combining
T-junctions, any number of branches can be achieved (ie: one tube can
branch into three by using two T-junctions).
Air tank
Air tanks are an important piece to most larger pneumatic designs, as
they allow air power to be easily stored for later retrieval.
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Pneumatic distribution block
These pieces used a special kind of one-way valve inside of them, and
three ports on the outside. The leftmost port could only have air going
into it, no air would ever come out. The middle port could have air goingin or out. The right port could only have air coming out of it, no air
could go into it.
Using these, it was possible to make the Generation 1 cylinders pull
down as well as push up, however the pulling wasn't as strong as the
pushing, and this prompted.
Pneumatic principles
Pneumatic projects usually include a compressor made from a
combination of a electric motor and pneumatic pump, together with a
pressure switch which will activate the motor when greater pressure is
required.
The pneumatic elements are most commonly used to resemble and take
the function of hydraulic cylinders in appropriate models, actuating a
digging arm or crane, for example. They can, however, also be used to
build a pneumatic engine, which converts air pressure into rotary motion
using the same principles as a steam engine. However, the cylinders are
not optimised for this purpose, and such engines tend to be slow and
lack power unless the cylinder inlets are enlarged.
Because a slight delay is involved between increased pressure and
cylinder movement, various feedback loops can be used whereby one
pneumatic component can activate another in a series of mechanical
events.
Pneumatics can be configured in such a way that electronic circuits can
be replicated. These circuits can then be combined to create digital
computers
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DESIGN CONSIDERATION
Pneumatic subsystem
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The above diagram shows the schematic of one pneumatic cylinder.
Pneumatic cylinder
diameter = 30mm
piston rod diameter = 12mm max. extendable length = 300mm
Valve
5/3 valve, closed in neutral position simple on/off type, non proportional nominal width = 5mm nominal throughput = 350 ltr/min min. time to switch = 20ms to control the movement of the piston the valve is switched at a
high rate, shifting the switch ratio to cause motion in the desired
direction at the desired speed
Supply pressure manifold
holds all six valves including the silencers/dampenersSilencer/Dampener
adjustable dampener to control the outgoing airflowTubing
tubes inner diameter = 4.5mm
Filter/Regulator
filters primary air supply allows for regulating the primary pressure (currently adjusted to 5
bar)
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Primary air supply (compressor)
max. pressure = 2 bar (29 psi) power = .4 Kw(approx) airflow max. 25 to 35 ltr/min tank volume = 24 ltr
Status
The pneumatic hardware is operative, only one cylinder can be used at
the monent.
There are three major considerations in the design of cranes. First, the
crane must be able to lift the weight of the load; second, the crane mustnot topple; third, the crane must not rupture.
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Status
The pneumatic hardware is operative, only one cylinder can be used at
the monent.
There are three major considerations in the design of cranes. First, the
crane must be able to lift the weight of the load; second, the crane must
not topple; third, the crane must not rupture.
Lifting capacity
Cranes illustrate the use of one or moresimple machinesto
createmechanical advantage.
Thelever. A balance crane contains a horizontal beam (the lever)pivoted about a point called thefulcrum. The principle of the lever
allows a heavy load attached to the shorter end of the beam to be
lifted by a smallerforceapplied in the opposite direction to the longer
end of the beam. The ratio of the load's weight to the applied force is
equal to the ratio of the lengths of the longer arm and the shorter arm,
and is called themechanical advantage.
Thepulley. A jib crane contains a tilted strut (thejib) that supports afixed pulley block. Cables are wrapped multiple times round the fixed
block and round another block attached to the load. When the free
end of the cable is pulled by hand or by a winding machine, the
pulley system delivers a force to the load that is equal to the applied
force multiplied by the number of lengths of cable passing between
the two blocks. This number is the mechanical advantage.
Thehydraulic cylinder. This can be used directly to lift the load orindirectly to move the jib or beam that carries another lifting device.
Cranes, like all machines, obey the principle ofconservation of energy.
This means that theenergydelivered to the load cannot exceed the
energy put into the machine. For example, if a pulley system multiplies
the applied force by ten, then the load moves only one tenth as far as the
applied force. Since energy is proportional to force multiplied by
http://en.wikipedia.org/wiki/Simple_machinehttp://en.wikipedia.org/wiki/Simple_machinehttp://en.wikipedia.org/wiki/Simple_machinehttp://en.wikipedia.org/wiki/Mechanical_advantagehttp://en.wikipedia.org/wiki/Mechanical_advantagehttp://en.wikipedia.org/wiki/Leverhttp://en.wikipedia.org/wiki/Leverhttp://en.wikipedia.org/wiki/Leverhttp://en.wikipedia.org/wiki/Leverhttp://en.wikipedia.org/wiki/Leverhttp://en.wikipedia.org/wiki/Leverhttp://en.wikipedia.org/wiki/Forcehttp://en.wikipedia.org/wiki/Forcehttp://en.wikipedia.org/wiki/Mechanical_advantagehttp://en.wikipedia.org/wiki/Mechanical_advantagehttp://en.wikipedia.org/wiki/Pulleyhttp://en.wikipedia.org/wiki/Pulleyhttp://en.wikipedia.org/wiki/Pulleyhttp://en.wikipedia.org/wiki/Hydraulicshttp://en.wikipedia.org/wiki/Hydraulicshttp://en.wikipedia.org/wiki/Hydraulicshttp://en.wikipedia.org/wiki/Conservation_of_energyhttp://en.wikipedia.org/wiki/Conservation_of_energyhttp://en.wikipedia.org/wiki/Conservation_of_energyhttp://en.wikipedia.org/wiki/Energyhttp://en.wikipedia.org/wiki/Energyhttp://en.wikipedia.org/wiki/Energyhttp://en.wikipedia.org/wiki/Energyhttp://en.wikipedia.org/wiki/Conservation_of_energyhttp://en.wikipedia.org/wiki/Hydraulicshttp://en.wikipedia.org/wiki/Pulleyhttp://en.wikipedia.org/wiki/Mechanical_advantagehttp://en.wikipedia.org/wiki/Forcehttp://en.wikipedia.org/wiki/Leverhttp://en.wikipedia.org/wiki/Leverhttp://en.wikipedia.org/wiki/Mechanical_advantagehttp://en.wikipedia.org/wiki/Simple_machine8/2/2019 Vikrant Project
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distance, the output energy is kept roughly equal to the input energy (in
practice slightly less, because some energy is lost tofrictionand other
inefficiencies).
The same principle can operate in reverse. In case of some problem, the
combination of heavy load and great height can accelerate small objects
to tremendous speed . Such projectiles can result in severe damage to
nearby structures and people. Cranes can also get in chain reactions; the
rupture of one crane may in turn take out nearby cranes. Cranes need to
be watched carefully.
Stability
For stability, the sum of allmomentsabout any point such as the base of
the crane must equate to zero. In practice, the magnitude of load that ispermitted to be lifted (called the "rated load") is some value less than the
load that will cause the crane to tip (providing a safety margin). Cranes,
the stability-limited rated load for a crawler crane is 65% of the tipping
load.
But the stability-limited rated load for a mobile crane supported on
outriggers is 85% of the tipping load accordance with US standard.
These requirements, along with additional safety-related aspects of crane
design, are established by the American Society of MechanicalEngineers in the volume ASME B30.5-2007Mobile and Locomotive
Cranes.
Standards for cranes mounted on ships or offshore platforms are
somewhat stricter because of the dynamic load on the crane due to
vessel motion. Additionally, the stability of the vessel or platform must
be considered.
Stress within the base must be less than the yield stress of the material or
the crane will fail.
http://en.wikipedia.org/wiki/Frictionhttp://en.wikipedia.org/wiki/Frictionhttp://en.wikipedia.org/wiki/Frictionhttp://en.wikipedia.org/wiki/Thermodynamic_efficiencyhttp://en.wikipedia.org/wiki/Thermodynamic_efficiencyhttp://en.wikipedia.org/wiki/Moment_(physics)http://en.wikipedia.org/wiki/Moment_(physics)http://en.wikipedia.org/wiki/Moment_(physics)http://en.wikipedia.org/wiki/Moment_(physics)http://en.wikipedia.org/wiki/Thermodynamic_efficiencyhttp://en.wikipedia.org/wiki/Friction8/2/2019 Vikrant Project
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Hydraulics vs Pneumatics
There are almost no significant differences between hydraulics andand for non-engineers but if you examine further, there are lots of
technical uniqueness in each system. By definition alone, hydraulics is very different from pneumatics
because it is used in controlling, transmitting and harnessing power
using pressured fluids. The latter is dealing more on studying the
impact of pressurized gases and how it influences mechanical
movement. Hydraulics is frequently used in the concepts of dams,
rivers, turbines and even erosion whereas pneumatics is applied in
various fields of dentistry, mining and general construction among
others.
The material or substance used differs between the two. Inhydraulics, the substance used is an incompressible fluid medium
wherein the most common example is oil. Pneumatics, on the
contrary, makes use of a very compressible gas like air itself or an
appropriate puregas.
Another difference between the two when applied is the strength ofthe pressures used in their applications. Hydraulic systems use agreater amount of pressure compared to pneumatic applications. In
pneumatics, only 80-100 psi (pounds per square inch) of pressure
is used for its industrial applications. Hydraulic-based applications
frequently use pressures that range from 1,000-5,000 psi.
Nevertheless, other more advanced hydraulic systems even use
pressures of up to 10,000 psi. Because of this high power demand,
hydraulic systems chiefly use bigger components while pneumatic
systems use smaller ones in most applications.
With regard to the control of applications, pneumatic systems aredeemed to be simpler and easier to handle than hydraulic systems.
Most operators say that using pneumatics is just like the light
switch that makes you choose between two simple choices of on
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or off. This is true because most pneumatics is designed with
simple cylinders and standard components only. An exception in
the simplicity of either a hydraulic or pneumatic device would
come if the entire system is automated.
Summary:
1. By definition, hydraulics is used in controlling or harnessing
power with the use of pressurized fluids whereas pneumatics
studies how pressurized gases influences mechanical motion or
movement.
2. Hydraulics uses an incompressible fluid medium like oil
whereas pneumatics uses a compressible gas like air.3. Hydraulic applications demand greater pressures during
operations that reach thousands of pounds per square inch whereas
pneumatic applications only require 100 psi pressures more or less.
4. Most hydraulic applications generally use bigger components
that pneumatic applications.
5. Hydraulic systems are generally more difficult to operate
compared to pneumatic applications.
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Worksheet
Capacity*
APPROX
KILOGRAM
.10-25
Type of Crane*
PNEUMATIC SYSTEM BASED
Span (Center to Center
of rail)*
__
Mtr.
__
Height of Lift*
UPTO
Mtr.
0.70
Minimum Speed
Maximum Speed
__
__
Mtr./Min. __
Mtr./Min. __
Power supply
Air Comperssor
A.C Source
3000 -4000 r.s
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Tubing 1000 -1500 r.s
Pneumatic cylinder
4000 -6000 r.s
Jib and Hook 3500r.s
Bearings and
fabrication
2500 -4500 r.s
*
Accessories
3000 r.s
Wooden block 1000 r.s
Electric motor 4000- 6000 r.s
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CONCLUSION
At last we came to a conclusion while working on the synopsis and
market survey for our pneumatic crane we faced many difficulties and
now find ourselves prepared enough to face the heat of stress in
upcoming of our project in working.
We owe to our guides and ourselves that we will work hard and
use best innovation of our mind to make our project happen.
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Biliography
Random article Market survey details about components www.referenceforbusiness.com www.howstuffwork.com www.netsuite.com
http://en.wikipedia.org/wiki/Special:Randomhttp://en.wikipedia.org/wiki/Special:Randomhttp://www.referenceforbusiness.com/http://www.referenceforbusiness.com/http://www.howstuffwork.com/http://www.howstuffwork.com/http://www.netsuite.com/http://www.netsuite.com/http://www.netsuite.com/http://www.howstuffwork.com/http://www.referenceforbusiness.com/http://en.wikipedia.org/wiki/Special:Random8/2/2019 Vikrant Project
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Alternative pneumatic system
There are similar pneumatics system for robotic and control technology
hobbyists. This system includes an electrically activated air solenoid, a
feature not available in the pneumatic range.
A number of hobbyists have also constructed additional components
such as larger air tanks and solenoids to complement the standardpneumatic components.
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Sizing a Cylinder
To determine the size cylinder that is needed for a particular system,
certainparameters must be known. First of all, a total evaluation of the
load must be made.This total load is not only the basic load that must be
moved, but also includes anyfriction and the force needed to accelerate
the load. Also included must be the forceneeded to exhaust the air from
the other end of the cylinder through the attachedlines, control valves,
etc. Any other force that must be overcome must also beconsidered aspart of the total load. Once the load and required force characteristics
are determined, a working pressure should be assumed. This working
pressure that is selected MUST be the pressure seen at the cylinder's
piston when motion is takingplace. It is obvious that cylinder's working
pressure is less than the actual systempressure due to the flow losses in
lines and valves.With the total load (including friction) and working
pressure determined, thecylinder size may be calculated using Pascal's
Law. Force is equal to pressure beingapplied to a particular area. The
formula describing this action is:Force = Pressure * AreaForce is proportional to pressure and area. When a cylinder is used to
clamp or
press, its output force can be computed as follows: F = P * A
P = pressure (PSI (Bar) (Pascal's))
F = force (pounds (Newtons))
A = area (square inches (square meters))
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Pneumatics Problem #1Application:Finished parts are accumulating on the end of a conveyor. The parts
need to be
transferred on to a connecting conveyor that carries them to the final
inspection
and packaging stations. The technician needs to be able to activate and
then
release a transfer device powered by a pneumatic cylinder.Objective:
To be able to design and assemble a circuit that extends and retracts a
single
acting, spring return cylinder.
Circuit Problem:Using the given components and layout, design a schematic circuit
which will operate a spring return cylinder with a two position, spring
offset, three-way valve.
Pneumatics Problem #2Application:Parts need to be clamped for a drilling operation. The technician needs
to activate
and deactivate a pneumatic clamp that holds the part in a fixture on the
drilling
machine. The clamp must be activated before the drilling cycle begins
and
deactivated at the end of the drilling cycle.
Objective:
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To be able to design and assemble a circuit that extends and retracts a
double
acting cylinder.
Circuit Problem:Using the given components and layout, design a schematic circuit
which will operate a double acting cylinder with a two position four-way
valve.
Alternative pneumatic system
There are similar pneumatics system for robotic and control technology
hobbyists. This system includes an electrically activated air solenoid, a
feature not available in the pneumatic range.
A number of hobbyists have also constructed additional components
such as larger air tanks and solenoids to complement the standard
pneumatic components.
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Pneumatic Transmission of Energy
The reason for using pneumatics, or any other type of energy
transmission on a machine, is to perform work. The accomplishment of
work requires the application of kinetic energy to a resisting object
resulting in the object moving through a distance. In a pneumatic
system, energy is stored in a potential state under the form ofcompressed air. Working energy (kinetic energy and pressure) results in
a pneumatic system when the compressed air is allowed to expand. For
example, a tank is charged to 100 PSIA with compressed air. When the
valve at the tank outlet
is opened, the air inside the tank expands until the pressure inside the
tank equals the atmospheric pressure. Air expansion takes the form of
airflow.
To perform any applicable amount of work then, a device is needed
which can supply an air tank with a sufficient amount of air at a desired
pressure. This device is positive displacement compressor.