DESIGN AND FABRICATION OF FOUR BAR CRANE MECHANISM

A MINI- PROJECT REPORT

Submitted by

J.IMMANUL JOHN THOMAS U07ME052

G.MANIKANDAN U07ME068

K.MOHAMED NATHAR OLI U07ME076

In partial fulfilment for the award of the degree

Of
BACHELOR OF TECHNOLOGY
IN
MECHANICAL ENGINEERING
UNDER THE GUIDANCE OF
Mr. K. JEGADEESAN
LECTURER

BHARATH UNIVERSITY
OCTOBER 2010
 DEPARTMENT OF MECHANICAL ENGINEERING
BHARATH UNIVERSITY, CHENNAI- 600 073
OCTOBER 2010

BONAFIDE CERTIFICATE

Certified that this project entitled DESIGN AND FABRICATION OF

FOUR BAR CRANE MECHANISM is a bonafide work of J.IMMANUVEL
JOHN THOMAS, G.MANIKANDAN, K.MOHAMED NATHER OLI who
carried out the project work under my supervision.

Dr. T. JAYACHANDRA PRABHU Mr. K.JEGADEESAN

HEAD OF THE DEPARTMENT, GUIDE AND LECTURER,
Mechanical Engineering, Mechanical Engineering,
Bharath University, Bharath University,
173, Agarham Road, 173, Agarham Road,
Selaiyur, Selaiyur,
Chennai 600 073 Chennai 600 073
 ACKNOWLEDGEMENT

With deep sense of gratitude, we thank our project Guide Mr. K. JEGADEESAN,
Lecturer of Mechanical Department and our project co-ordinator
Mr.A.KUMARASWAMY, senior lecturer of mechanical department, whose initiation and
guidance led us to bring out this project successfully.
We are highly indebted to Dr. T. JAYACHANDRA PRABU, Professor and Head
of the Department of Mechanical Engineering for this valuable encouragement and timely
guidance during this tenure. We express our profound thanks to him.
We thank one and all the others who co- operated with us in bringing out this project this
successfully.
 AIM

The aim of this project is to design a four bar crane mechanism of required dimension to
lift the heavy loads with comparatively minimum effort as the input.
 LIST OF CONTENTS

CHAPTER NO. TITLE PAGE NO

AIM
LIST OF FIGURES

1 INTRODUCTION
1.1 working of four bar crane 1-2
1.2 crane structure 3
1.3 couple curve for crane mechanism 3-4
1.4 crane effort 4-5
1.5 field of stretch 5-6
1.6 working of linkages 6-7
1.7 mechanical principles 7
2 DESIGN CALCULATION
2.1 modeling and simulation 9-11
2.2 Calculation 12

3 OPERATING SHEET
3.1 lifting capacity 13-14
3.3 stability of the crane 14
3.3 forces of crane 15
3.4 types of crane 16-22
3.5 similar machine 23
4 PARTS AND ASSEMBLY 24
5 REFERENCE 26
 INTRODUCTION

A crane structure for hoisting, holding and/or towing heavy loads is provided. The crane
structure includes a frame, for example a wrecker truck chassis, a boom support assembly, and a
pair of booms each having a first member pivotally mounted to the boom support assembly so
that the first boom and the second boom are pivotal in parallel vertical planes. Each of the first
boom and the second boom also has a fluid operable second member slidably received by the
first member. A control system is in operative communication with the first boom, the second
boom and a winch assembly to independently activate each second member to extend from and
retract to its corresponding first member, to pivotally position each boom with respect to the
frame, and to activate the winch assembly to retract and extend cables about free ends of the
respective second members.

1.1 WORKING OF FOUR BAR CRANE MECHANISM

A four-bar linkage or simply a 4-bar or four-bar is the simplest movable linkage. It

consists of four rigid bodies (called bars or links), each attached to two others by single joints or
pivots to form a closed loop.

Four-bars are simple mechanisms common in mechanical engineering machine design

and fall under the study of kinematics. If each joint has one rotational degree of freedom (i.e., it
is a pivot), then the mechanism is usually planar, and the 4-bar is determinate if the positions of
any two bodies are known (although there may be two solutions). One body typically does not
move (called the ground link, fixed link, or the frame), so the position of only one other body
is needed to find all positions.

The two links connected to the ground link are called grounded links. The remaining
link, not directly connected to the ground link, is called the coupler link. In terms of mechanical
action, one of the grounded links is selected to be the input link, i.e., the link to which an
external force is applied to rotate it. The second grounded link is called the follower link, since
its motion is completely determined by the motion of the input link.
 Planar four-bar linkages perform a wide variety of motions with a few simple parts. They
were also popular in the past due to the ease of calculations, prior to computers, compared to
more complicated mechanisms.

Grashof's law is applied to pinned linkages and states; The sum of the shortest and longest link
of a planar four-bar linkage cannot be greater than the sum of remaining two links if there is to
be continuous relative motion between the links. Below are the possible types of pinned, four-bar
linkages;

Types of four-bar linkages, s = shortest link, = longest link

1.2 Crane structure

1.3 Couple curve for crane mechanism:

A modern crawler type derrick crane with. The lattice boom is fitted with a jib.
An old manual crane with a pivoted boom. The incline of the boom is controlled by means of
chains, sprockets and gear.A crane is a lifting machine, generally equipped with a winder (also
called a wire rope drum), wire ropes or chains and sheaves, that can be used both to lift and
lower materials and to move them horizontally. It uses one or more simple machines to create
mechanical advantage and thus move loads beyond the normal capability of a human. Cranes are
commonly employed in the transport industry for the loading and unloading of freight, in the
construction industry for the movement of materials and in the manufacturing industry for the
assembling of heavy equipment.
Gantry cranes for handling containerized cargo.Mini - crane generally used for constructing
buildingTwo different types of cranes.The first construction cranes were invented by the Ancient
Greeks and were powered by men or beasts of burden, such as donkeys. These cranes were used
for the construction of tall buildings. Larger cranes were later developed, employing the use of
human treadwheels, permitting the lifting of heavier weights. In the High Middle Ages, harbour
cranes were introduced to load and unload ships and assist with their construction some were
built into stone towers for extra strength and stability. The earliest cranes were constructed from
wood, but cast iron and steel took over with the coming of the Industrial Revolution.

For many centuries, power was supplied by the physical exertion of men or animals, although
hoists in watermills and windmills could be driven by the harnessed natural power. The first
'mechanical' power was provided by steam engines the earliest steam crane being introduced in
the 18th or 19th century, with many remaining in use well into the late 20th century. Modern
cranes usually use internal combustion engines or electric motors and hydraulic systems to
provide a much greater lifting capability than was previously possible, although manual cranes
are still utilised where the provision of power would be uneconomic.

Cranes exist in an enormous variety of forms each tailored to a specific use. Sizes range from
the smallest jib cranes, used inside workshops, to the tallest tower cranes, used for constructing
high buildings. For a while, mini - cranes are also used for constructing high buildings, in order
to facilitate constructions by reaching tight spaces. Finally, we can find larger floating cranes,
generally used to build oil rigs and salvage sunken ships. This article also covers lifting machines
that do not strictly fit the above definition of a crane, but are generally known as cranes, such as
stacker cranes and loader cranes.

1.4 Crane effort:

The crane for lifting heavy loads was invented by the Ancient Greeks in the late 6th
century BC. The archaeological record shows that no later than c.515 BC distinctive cuttings for
both lifting tongs and lewis irons begin to appear on stone blocks of Greek temples. Since these
holes point at the use of a lifting device, and since they are to be found either above the center of
gravity of the block, or in pairs equidistant from a point over the center of gravity, they are
regarded by archaeologists as the positive evidence required for the existence of the crane.The
introduction of the winch and pulley hoist soon lead to a widespread replacement of ramps as the
main means of vertical motion. For the next two hundred years, Greek building sites witnessed a
sharp drop in the weights handled, as the new lifting technique made the use of several smaller
stones more practical than of fewer larger ones. In contrast to the archaic period with its tendency
to ever-increasing block sizes, Greek temples of the classical age like the Parthenon invariably
featured stone blocks weighing less than 15-20 metric tons. Also, the practice of erecting large
monolithic columns was practically abandoned in favour of using several column drums.

Although the exact circumstances of the shift from the ramp to the crane technology
remain unclear, it has been argued that the volatile social and political conditions of Greece were
more suitable to the employment of small, professional construction teams than of large bodies
of unskilled labour, making the crane more preferable to the Greek polis than the more labour-
intensive ramp which had been the norm in the autocratic societies of Egypt or Assyria.

Motion of rotation:

The simplest Roman crane, the trispastos, consisted of a single-beam jib, a winch, a rope, and a
block containing three pulleys. Having thus a mechanical advantage of 3:1, it has been calculated
that a single man working the winch could raise assuming that 50 kg represent the maximum
effort a man can exert over a longer time period. Heavier crane types featured five pulleys
(pentaspastos) or, in case of the largest one, a set of three by five pulleys (Polyspastos) and came
with two, three or four masts, depending on the maximum load. The polyspastos, when worked
by four men at both sides of the winch, could already lift 3000 kg (3 ropes x 5 pulleys x 4 men x
50 kg = 3000 kg). In case the winch was replaced by a treadwheel, the maximum load even
doubled to 6000 kg at only half the crew, since the treadwheel possesses a much bigger
mechanical advantage due to its larger diameter. This meant that, in comparison to the
construction of the Egyptian Pyramids, where about 50 men were needed to move a 2.5 ton stone
block up the ramp (50 kg per person), the lifting capability of the Roman polyspastos proved to
be 60 times higher (3000 kg per person).

However, numerous extant Roman buildings which feature much heavier stone blocks than those
handled by the polyspastos indicate that the overall lifting capability of the Romans went far
beyond that of any single crane. At the temple of Jupiter at Baalbek, for instance, the architrave
blocks weigh up to 60 tons each, and one corner cornice block even over 100 tons, all of them
raised to a height of about 19 m. In Rome, the capital block of Trajan's Column weighs 53.3 tons,
which had to be lifted to a height of about 34 m (see construction of Trajan's Column).
It is assumed that Roman engineers lifted these extraordinary weights by two measures (see
picture below for comparable Renaissance technique): First, as suggested by Heron, a lifting
tower was set up, whose four masts were arranged in the shape of a quadrangle with parallel
sides, not unlike a siege tower, but with the column in the middle of the structure (Mechanica
3.5). Second, a multitude of capstans were placed on the ground around the tower, for, although
having a lower leverage ratio than treadwheels, capstans could be set up in higher numbers and
run by more men (and, moreover, by draught animals). This use of multiple capstans is also
described by Ammianus Marcellinus (17.4.15) in connection with the lifting of the Lateranense
obelisk in the Circus Maximus (ca. 357 AD). The maximum lifting capability of a single capstan
can be established by the number of lewis iron holes bored into the monolith. In case of the
Baalbek architrave blocks, which weigh between 55 and 60 tons, eight extant holes suggest an
allowance of 7.5 ton per lewis iron, that is per capstan. Lifting such heavy weights in a concerted
action required a great amount of coordination between the work groups applying the force to the
capstans.

1.5 FIELD OF STRECH:

vertical transport could be done more safely and inexpensively by cranes than by
customary methods. Typical areas of application were harbors, mines, and, in particular, building
sites where the treadwheel crane played a pivotal role in the construction of the lofty Gothic
cathedrals. Nevertheless, both archival and pictorial sources of the time suggest that newly
introduced machines like treadwheels or wheelbarrows did not completely replace more labor-
intensive methods like ladders, hods and handbarrows. Rather, old and new machinery continued
to coexist on medieval construction sites and harbors.Apart from treadwheels, medieval
depictions also show cranes to be powered manually by windlasses with radiating spokes, cranks
and by the 15th century also by windlasses shaped like a ship's wheel. To smooth out
irregularities of impulse and get over 'dead-spots' in the lifting process flywheels are known to be
in use as early as 1123.The exact process by which the treadwheel crane was reintroduced is not
recorded, although its return to construction sites has undoubtedly to be viewed in close
connection with the simultaneous rise of Gothic architecture. The reappearance of the treadwheel
crane may have resulted from a technological development of the windlass from which the
treadwheel structurally and mechanically evolved. Alternatively, the medieval treadwheel may
represent a deliberate reinvention of its Roman counterpart drawn from Vitruvius' De
architectura which was available in many monastic libraries.

1.6 WORKING OF FOUR BAR LINKAGE:

Single treadwheel crane working from top of the buildingThe medieval treadwheel was a
large wooden wheel turning around a central shaft with a treadway wide enough for two workers
walking side by side. While the earlier 'compass-arm' wheel had spokes directly driven into the
central shaft, the more advanced 'clasp-arm' type featured arms arranged as chords to the wheel
rim, giving the possibility of using a thinner shaft and providing thus a greater mechanical
advantage.Contrary to a popularly held belief, cranes on medieval building sites were neither
placed on the extremely lightweight scaffolding used at the time nor on the thin walls of the
Gothic churches which were incapable of supporting the weight of both hoisting machine and
load. Rather, cranes were placed in the initial stages of construction on the ground, often within
the building. When a new floor was completed, and massive tie beams of the roof connected the
walls, the crane was dismantled and reassembled on the roof beams from where it was moved
from bay to bay during construction of the vaults. Thus, the crane grew and wandered with the
building with the result that today all extant construction.
DISCRIPTION OF PREFERED:

Tower crane at the inland harbour of Trier from 1413.In contrast to modern cranes,
medieval cranes and hoists - much like their counterparts in Greece and Rome - were primarily
capable of a vertical lift, and not used to move loads for a considerable distance horizontally as
well. Accordingly, lifting work was organized at the workplace in a different way than today. In
building construction, for example, it is assumed that the crane lifted the stone blocks either from
the bottom directly into place, or from a place opposite the centre of the wall from where it could
deliver the blocks for two teams working at each end of the wall. Additionally, the crane master
who usually gave orders at the treadwheel workers from outside the crane was able to manipulate
the movement laterally by a small rope attached to the load. Slewing cranes which allowed a
rotation of the load and were thus particularly suited for dockside work appeared as early as
1340. While ashlar blocks were directly lifted by sling, lewis or devil's clamp (German
Teufelskralle), other objects were placed before in containers like pallets, baskets, wooden boxes
or barrels.It is noteworthy that medieval cranes rarely featured ratchets or brakes to forestall the
load from running backward. This curious absence is explained.

1.7 MECHANICAL PRINCIPLES:

Beyond the modern warship stands a crane constructed in 1742, used for mounting masts
to large sailing vessels. Copenhagen, DenmarkAccording to the "present state of knowledge"
unknown in antiquity, stationary harbor cranes are considered a new development of the Middle
Ages. The typical harbor crane was a pivoting structure equipped with double treadwheels. These
cranes were placed docksides for the loading and unloading of cargo where they replaced or
complemented older lifting methods like see-saws, winches and yards.Two different types of
harbor cranes can be identified with a varying geographical distribution: While gantry cranes
which pivoted on a central vertical axle were commonly found at the Flemish and Dutch
coastside, German sea and inland harbors typically featured tower cranes where the windlass and
treadwheels were situated in a solid tower with only jib arm and roof rotating.
2. DESIGN AND CALCULTION

2.1 Modelling and Simulation of a Four Bar Mechanism and Crane:

The link to which an external force is applied to rotate it. The second grounded link is called
the follower link, since its motion is completely determined by the motion of the input link.
Four Bar mechanism In the figure shown above the first link (input link) is called Crank, the
second link Coupler and the third link is the Follower. Objective: The objective of this
project is to simulate the four-bar mechanism using Pro-E and compare the analysis results
with the analytical calculations. The dimensions of the Four bar mechanism of interest are
shown in the figure below:0.50 0.50 6.00 Length of the Crank : 6 in Length of the Coupler:
24.7386 in Length of the Follower: 12 in The Crank and the Coupler have to be of negligible
mass. So the density is appropriately chosen. The various parameters are tabulated as below:
Volume = length * width*thickness + pi * r^2*thickness r: radius of curvature of the ends
Link# Length(in) Width(in) Thickness(in) v1 Density Volume Mass Crank 6 1 0.5 0.3925
1.00E-07 3.3925 3.3925E-07 Coupler 24.7386 1 0.5 0.3925 1.00E-07 12.7618 1.27618E-06
Follower 12 1 0.5 0.3925 0.0007324 6.3925 0.004681867 The Four bar[Project-4]
[Mechanism Studies] Sasi Bhushan Beera #35763829 Srikanth Avala #35762927Project4
Four Bar Mechanism Introduction: A four bar linkage or simply a four-bar mechanism is the
simplest movable linkage. It consists of four rigid bodies (called bars or links), each attached
to two others by single joints or pivots to form a closed loop. If each joint has one rotational
degree of freedom (i.e., it is a pivot), then the mechanism is usually planar, and the four-bar
is determinate if the positions of any two bodies are known (although there may be two
solutions). One body typically does not move (called the ground link, fixed link, or the
frame), so the position of only one other body is needed to find all positions. The two links
connected to the ground are called grounded links. The remaining one link, not directly
connected to the ground link, is called coupler link. In terms of mechanical action, one of the
grounded links is selected to be the input link, i.e., mechanism built in pro-E is as shown in
the figure below:
Four Bar in Pro-E Analysis: The Four bar mechanism is simulated in Pro-E and both kinematic
and dynamic analysis is done to measure the angle rates and angular acceleration. The Torque
and the reaction forces at the Crank- Ground joint are also measured and are shown in the figures
below: Initial Configuration: # Angle(rad) Rate(rad/s) Acceleration(rad.s^2) Crank pi/2 2*pi 0
Follower pi/2 TBD TBD The angular rates , accelerations of other joints and torque and reaction
forces at the Crank-ground joint are plotted as shown below:

1. W3 vs time W4 vs time
2. W3dot vs time W4dot vs time
3. Fx Fy
4. Moment Analytical Calculations: Notations: cos(th1) : C1 sin(th1) : S1 cos(th2):C2
sin(th2):S2 cos(th4):C4 sin(th4):S4 Closed loop equations: position level
l1*C1+l2*C2 = l0+l3*C4
5. l1*S1+l2*S2 =l3*S4 Differentiating the above set of equations w.r.t time we get
equations at velocity level: -l1*S1*w2-l2*S2*w3 = -l3*S4*w4
l1*C1*w2+l2*C2*w3 = l3*C4*w4 Now given w2 we can determine, w3 and w4
at the initial position. Differentiating the above equations w.r.t time we get
equations at acceleration level: -l1*S1*2-l1*C1*(w2^2)-l2*S2* 3-
l2*C2*(w3^2) = -l3*S4* 4-l3*C4*(w4^2) l1*C1*2-l1*S1*(w2^2)+l2*S2* 3-
l2*S2*(w3^2) = l3*C4* 4-l3*S4*(w4^2) 3 and 4 can be determined from the
above set of equations. Force Calculations: Rocker: F = (I03*w4dot)/(l3*cos(th))
Crank: Rx = -F* cos(th) Ry = -F*sin(th) M = -F*cos(th)*l1 Results: Since pro-E
uses relative angles we need to covert them to absolute angles before comparison #
Pro-E Analytical Relative Absolute Absolute w3 -360 0 0 w4 180 180 180 3
282.665 282.665 282.7473 4 141.354 141.354 141.3717
6. Force Analysis: The hand calculations for the force analysis are submitted in a
hand-written format. The results are tabulated as shown below: # Pro-E Analytical
Fx -0.0473429 0.0462 Fy -0.012 0.0115 Torque 0.284036 0.2772
7. Part B - The Dutch Crane Introduction: The crane below is a planar four-bar
mechanism mounted on a rotating platform. Its critical dimensions are shown in
the schematic below in meters. The maximum motion of the crane is given by its
 driven angle Q which varies from 49 degrees at maximum reach to 132 degrees at
minimum reach. Objective The objective here is to render the crane shown above
in ProE using reasonable representations for its components and create an
appropriate assembly. The then rendered assembly is to be animated using ProE
mechanism package. The rendered components: The major components are
modeled according to the crane shown in the fig above.
8. The Base: ``
9. The arm: The Rotor:
10. The supporter(long arm)
11. The final rendering of the assembly:

CALCULATION
four bar crane mechanism:

Derivation to get the values for the mechanism

Let us assume the value of AC as 15

 AC=15

From the given derivation we can find the remaining length

CB =0.27*AC

(i.e.) CB = 0.27*15 = 4.05

AC=15

(i.e.) AC=15 = 15

AC=15

ACand BD is derived from the given derivation

BD=0.83*AC
AC=15
BD=0.83*15
BD=12.45
EB of the link drived from the given derivation
EB=1.18*AC
EB=1.18*15
EB=17.70
AE of the link drived from the given derivation
AE=0.64*AC
AE=0.64*15
AE=9.6
Therefore the value is acquired from the given derivation.

AC=15, CB=4.05, BD=12.45, EB=17.7, AE=9.6

3.OPERATION SHEET

A lifting tower similar to that of the ancient Romans was used to great effect by the Renaissance
architect Domenico Fontana in 1586 to relocate the 361 t heavy Vatican obelisk in Rome. From
his report, it becomes obvious that the coordination of the lift between the various pulling teams
required a considerable amount of concentration and discipline, since, if the force was not
applied evenly, the excessive stress on the ropes would make them rupture.

Broken crane in Sermetal Shipyard, former do Brasil - Rio de Janeiro. The cause of the accident
was a lack of conservation and misuse of the equipment.
Cranes can mount many different utensils depending on load (left). Cranes can be remote-
controlled from the ground, allowing much more precise control, but without the view that a
position atop the crane provides (right).The stability of a mobile construction crane can be
jeopardized when outriggers sink into soft soil, which can result in the crane tipping over.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.

3.1 Lifting capacity

Cranes illustrate the use of one or more simple machines to create mechanical advantage.

The lever. A balance crane contains a horizontal beam (the lever) pivoted about a point.
The principle of the lever allows a heavy load attached to the shorter end of the beam to
be lifted by a smaller force applied 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 the mechanical advantage.
The pulley. A jib crane contains a tilted strut (the jib) that supports a fixed pulley block.
Cables are wrapped multiple times round the fixed block and round another block
attached to the load.
The hydraulic cylinder. This can be used directly to lift the load or indirectly to move the
jib or beam that carries another lifting device
 .

3.2 STABILITY OF THE CRANE:

Cranes, like all machines, obey the principle of conservation of energy. This means that the
energy delivered 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 distance, the output energy is
kept roughly equal to the input energy (in practice slightly less, because some energy is lost to
friction and 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 (see trebuchet). 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.For stability, the sum of all moments about any point such as the base of the
crane must equate to zero. In practice, the magnitude of load that is permitted to be lifted (called
the "rated load" in the US) is some value less than the load that will cause the crane to tip
(providing a safety margin).

3.3 FORCES OF THE CRANE :

Under US standards for mobile cranes, the stability-limited rated load for a crawler crane is 75%
of the tipping load. The stability-limited rated load for a mobile crane supported on outriggers is
85% of the tipping load. These requirements, along with additional safety-related aspects of
crane design, are established by the American Society of Mechanical Engineers in the volume
ASME B30.5-2007 Mobile 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.For stationary
pedestal or kingpost mounted cranes, the moment created by the boom, jib, and load is resisted
by the pedestal base or kingpost. Stress within the base must be less than the yield stress of the
material or the crane will fail.

3.4 TYPES OF CRANE:

Truck-mounted crane

A crane mounted on a truck carrier provides the mobility for this type of crane.Generally,
these cranes are able to travel on highways, eliminating the need for special equipment to
transport the crane. When working on the jobsite, outriggers are extended horizontally from the
chassis then vertically to level and stabilize the crane while stationary and hoisting. Many truck
cranes have slow-travelling capability (a few miles per hour) while suspending a load. Great care
must be taken not to swing the load sideways from the direction of travel, as most anti-tipping
stability then lies in the stiffness of the chassis suspension. Most cranes of this type also have
moving counterweights for stabilization beyond that provided by the outriggers. Loads
suspended directly aft are the most stable, since most of the weight of the crane acts as a
counterweight. Factory-calculated charts (or electronic safeguards) are used by crane operators to
determine the maximum safe loads for stationary (outriggered) work as well as (on-rubber) loads
and travelling speeds.

Sidelift crane
 A sidelifter crane is a road-going truck or semi-trailer, able to hoist and transport ISO standard
containers. Container lift is done with parallel crane-like hoists, which can lift a container from
the ground or from a railway vehicle.

Rough terrain crane

A crane mounted on an undercarriage with four rubber tires that is designed for pick-and-
carry operations and for off-road and "rough terrain" applications. Outriggers are used to level
and stabilize the crane for hoisting.

These telescopic cranes are single-engine machines, with the same engine powering the
undercarriage and the crane, similar to a crawler crane. In a rough terrain crane, the engine is
usually mounted in the undercarriage rather than in the upper, as with crawler crane.

All terrain crane

A mobile crane with the necessary equipment to travel at speed on public roads, and on rough
terrain at the job site using all-wheel and crab steering. ATs combine the roadability of Truck-
mounted Cranes and the manoeuvrability of Rough Terrain Cranes.ATs have 2-9 axles and are
designed for lifting loads up to 1,200 tonnes (1,323 ST; 1,181).

Crawler crane

A crawler is a crane mounted on an undercarriage with a set of tracks (also called crawlers)
that provide stability and mobility. Crawler cranes range in lifting capacity from about 40 to
3,500 short tons (35.7 to 3,125.0 long tons; 36.3 to 3,175.1 t).Crawler cranes have both
advantages and disadvantages depending on their use. Their main advantage is that they can
move around on site and perform each lift with little set-up, since the crane is stable on its tracks
with no outriggers. In addition, a crawler crane is capable of traveling with a load. The main
disadvantage is that they are very heavy, and cannot easily be moved from one job site to another
without significant expense. Typically a large crawler must be disassembled and moved by
trucks, rail cars or ships to its next location.

Railroad crane
 A railroad crane has flanged wheels for use on railroads. The simplest form is a crane
mounted on a flatcar. More capable devices are purpose-built.Different types of crane are used
for maintenance work, recovery operations and freight loading in goods yards.

Floating crane

Floating cranes are used mainly in bridge building and pot construction, but they are also used
for occasional loading and unloading of especially heavy or awkward loads on and off ships.
Some floating cranes are mounted on a pontoon, others are specialized crane barges with a lifting
capacity exceeding 10,000 short tons (8,929 long tons; 9,072 t) and have been used to transport
entire bridge sections. Floating cranes have also been used to salvage sunken ships.Crane vessels
are often used in offshore construction. The largest revolving cranes can be found on SSCV
Thialf, which has two cranes with a capacity of 7,100 tonnes(7,826 ST; 6,988 LT) each.

Aerial crane

Aerial crane or 'Sky cranes' usually are helicopters designed to lift large loads. Helicopters are
able to travel to and lift in areas that are difficult to reach by conventional cranes. Helicopter
cranes are most commonly used to lift units/loads onto shopping centers and highers. They can
lift anything within their lifting capacity, (cars, boats, swimming pools, etc.). They also perform
disaster relief after natural disasters for clean-up, and during wild-fires they are able to carry
huge buckets of water to extinguish fires.Some aerial cranes, mostly concepts, have also used
lighter-than air aircraft, such as airships.

Fixed

Exchanging mobility for the ability to carry greater loads and reach greater heights due to
increased stability, these types of cranes are characters that they, or at least their main structure
does not move during the period of use. However, many can still be assembled and
disassembled.
Tower crane

A tower crane rotates on its axis before lowering the lifting hook.Tower cranes are a modern
form of balance crane that consist of the same basic parts. Fixed to the ground on a concrete slab
(and sometimes attached to the sides of structures as well), tower cranes often give the best
combination of height and lifting capacity and are used in the construction of tall buildings. The
base is then attached to the mast which gives the crane its height. Further the mast is attached to
the slewing unit (gear and motor) that allows the crane to rotate. On top of the slewing unit there
are three main parts which are: the long horizontal jib (working arm), shorter counter-jib, and the
operators cab.

The long horizontal jib is the part of the crane that carries the load. The counter-jib carries a
counterweight, usually of concrete blocks, while the jib suspends the load to and from the center
of the crane. The crane operator either sits in a cab at the top of the tower or controls the crane by
radio remote control from the ground. In the first case the operator's cab is most usually located
at the top of the tower attached to the turntable, but can be mounted on the jib, or partway down
the tower. The lifting hook is operated by the crane operator using electric motors to manipulate
wire rope cables through a system of sheaves. The hook is located on the long horizontal arm to
lift the load which also contains its motor.

In order to hook and unhook the loads, the operator usually works in conjunction with a signal
(known as 'rigger' or 'swamp'). They are most often in radio contact, and always use hand signals.
The rigger or directs the schedule of lifts for the crane, and is responsible for the safety of the
rigging and loads. A tower crane is usually assembled by a telescopic jib (mobile) crane of
greater reach (also see "self-erecting crane" below) and in the case of tower cranes that have
risen while constructing very tall skyscrapers, a smaller crane (or derrick) will often be lifted to
the roof of the completed tower to dismantle the tower crane afterwards.

The average fee to rent a 150-foot (46 m) crane is $60,000 for assembly and disassembly and an
additional $15,000 per month. It is often claimed that a large fraction of the tower cranes in the
world are in use in UAE. The exact percentage remains an open question.[

Self-erecting crane
 Generally a type of tower crane, these cranes, also called self-assembling or "Kangaroo"
cranes, lift themselves off the ground using jacks, allowing the next section of the tower to be
inserted at ground level or lifted into place by the partially erected crane itself. They can thus be
assembled without outside help, or can grow together with the building or structure they are
erecting.

Telescopic crane

A telescopic crane has a boom that consists of a number of tubes fitted one inside the other. A
hydraulic or other powered mechanism extends or retracts the tubes to increase or
decrease the total length of the boom. These types of booms are often used for short
term construction projects, rescue jobs, lifting boats in and out of the water, etc. The
relative compactness of telescopic booms make them adaptable for many mobile
applications.

Note that while telescopic cranes are not automatically mobile cranes, many of them are. These
are often truck-mounted.

Hammerhead crane

The "hammerhead", or giant cantilever, crane is a fixed-jib crane consisting of a steel-braced

tower on which revolves a large, horizontal, double cantilever the forward part of this cantilever
or jib carries the lifting trolley, the jib is extended backwards in order to form a support for the
machinery and counter-balancing weight. In addition to the motions of lifting and revolving,
there is provided a so-called "racking" motion, by which the lifting trolley, with the load
suspended, can be moved in and out along the jib without altering the level of the load. Such
horizontal movement of the load is a marked feature of later crane design. These cranes are
generally constructed in large sizes, up to 350 tons.

The design of evolved first in Germany around the turn of the 19th century and was adopted and
developed for use in British shipyards to support the battleship construction program from 1904
to 1914. The ability of the hammerhead crane to lift heavy weights was useful for installing large
pieces of battleships such as arm plate and gun barrels. Giant cantilever cranes were also
installed in naval shipyards in Japan and in the USA. The British Government also installed a
giant cantilever crane at the Singapore Naval Base (1938) and later a copy of the crane was
installed at Garden Island Naval Dockyard in Sydney (1951). These cranes provided repair
support for the battle fleet operating far from Great Britain.

The principal engineering firm for giant cantilever cranes in the British Empire was Sir William
& Co Ltd building 14. Of around 60 built across the world few remain; 7 in England and
Scotland of about 15 worldwide.

The Titan Clydebank is one of the 4 Scottish cranes on the Clydebank and preserved as a tourist
attraction.

Level luffing crane

Normally a crane with a hinged jib will tend to have its hook also move up and down as the
jib moves. A level crane is a crane of this common design, but with an extra mechanism to keep
the hook level.

Gantry crane

A gantry crane has a hoist in a fixed machinery house or on a trolley that runs horizontally
along rails, usually fitted on a single beam (mono-girder) or two beams (twin-girder). The crane
frame is supported on a gantry system with equalized beams and wheels that run on the gantry
rail, usually perpendicular to the trolley travel direction. These cranes come in all sizes, and
some can move very heavy loads, particularly the extremely large examples used in shipyards or
industrial installations. A special version is the container crane (or "Portainer" crane, named by
the first manufacturer), designed for loading and unloading ship-borne containers at a port.

Overhead crane

Also known as a 'suspended crane', an overhead crane works very similar to a gantry crane
but instead of the whole crane moving, only the hoist / trolley assembly moves in one direction
along one or two fixed beams, often mounted along the side walls or on elevated columns in the
assembly area of factory. Some of these cranes can lift very heavy loads.

Deck crane

Located on the ships and boats, these are used for cargo operations or boat unloading and
retrieval where no shore unloading facilities are available. Most are diesel-hydraulic or electric-
hydraulic.

Jib crane

A jib crane is a type of crane where a horizontal member (jib or boom), supporting a
moveable hoist, is fixed to a wall or to a floor-mounted pillar. Jib cranes are used in industrial
premises and on military vehicles. The jib may swing through an arc, to give additional lateral
movement, or be fixed. Similar cranes, often known simply as hoists, were fitted on the top floor
of warehouse buildings to enable goods to be lifted to all floors.

Bulk-handling crane

Bulk-handling cranes are designed from the outset to carry a shell grab or bucket, rather than
using a hook and a sling. They are used for bulk cargoes, such as coal, minerals, scrap metal etc.

Loader crane
 A loader crane (also called a knuckle-boom crane or articulating crane) is a hydraulically-
powered articulated arm fitted to a truck or trailer, and is used for loading/unloading the vehicle.
The numerous jointed sections can be folded into a small space when the crane is not in use. One
or more of the sections may be telescopic. Often the crane will have a degree of automation and
be able to unload or stow itself without an operator's instruction.

Unlike most cranes, the operator must move around the vehicle to be able to view his load; hence
modern cranes may be fitted with a portable cabled or radio-linked control system to supplement
the crane-mounted hydraulic control levers.

In the UK and Canada, this type of crane is often known colloquially as a "Hiab", partly because
this manufacturer invented the loader crane and was first into the UK market, and partly because
the distinctive name was displayed prominently on the boom arm.

A rolloader crane is a loader crane mounted on a chassis with wheels. This chassis can ride on
the trailer. Because the crane can move on the trailer, it can be a light crane, so the trailer is
allowed to transport more goods.

Stacker crane

A crane with a forklift type mechanism used in automated (computer controlled) warehouses
(known as an automated storage and retrieval system (AS/RS)). The crane moves on a track in an
aisle of the warehouse. The fork can be raised or lowered to any of the levels of a storage rack
and can be extended into the rack to store and retrieve product.

3.5 Similar machines

The generally-accepted definition of a crane is a machine for lifting and moving heavy objects
by means of ropes or cables suspended from a movable arm. As such, a lifting machine that does
not use cables, or else provides only vertical and not horizontal movement, cannot strictly be
called a 'crane'.
Types of crane-like lifting machine include:

Block and tackle

Capstan (nautical)
Hoist (device)
Winch
Windlass
 CONCLUSION:

In this project four bar crane mechanism has been fabricated successfully. The four bar
crane mechanism has been designed in such a way that it can lift heavy loads.
 REFERENCE

1. Design of transmission elements by Dr T . JAYACHANDRA PRABHU.

2. Machine Design An Integrated Approach 2nd Edition By ROBERT L. NORTON.
3. A Text book Of Machine design by R.S. KHURMI & J.K. GUPTA.
4. Design of Machinery by ROBERT L. NORTON by McGRAW HILL Publications.
5. Reference Notes from seniors at Bharath University.
6. Theory of Machines by R.S. KHURMI by S. CHAND Publications.
7. Design Data Book by P.S.G. College of Technology.
WORKING PLACE

For five link lever screw mechanism

Meena industries
No. 80, 2nd street,
Sathyavadhi nagar,
padi