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Ê A 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. uses one or more simple machines to create mechanical advantage and thus move loads beyond the normal capability of a human. Ê ët
Ê Ancient concept of cranes 0Ancient Greece 0Ancient Rome
Ê 2he first
construction cranes were invented by the Ancient Greeks and were powered by men or beasts of burden
Ê ën ancient Greece the three-pulley-crane the simplest crane type (150 kg load) and the five pulley crane a medium-sized variant (450 kg load) werw found. Ê 2he crane for
lifting heavy loads was invented by the Ancient Greeks in the late 6th century BC.
Ê 2he simplest Roman crane, the 2rispastos,
consisted of a single-beam jib, a winch, a rope, and a block containing three pulleys. Having thus a mechanical advantage of 3:1. Ê 2he progress of
cranes lead to such levels that in the construction of Egyptian pyramids 50 men were needed to move a 2.5 ton stone block up the ramp
V Rn the basis of moblility cranes are of two types:iixed Cranes Ê Mobile or Movable Cranes Ê
Exchanging mobility for the ability to carry greater loads and reach greater heights as compare to any other type of cranes. Ê 2ower crane Ê Self-erecting crane Ê 2elescopic crane Ê Hammerhead crane Ê Level luffing crane Ê Gantry crane Ê Rverhead crane Ê Deck crane Ê Jib crane Ê Bulk-handling crane Ê Loader crane Ê Stacker crane
2 tower crane is a modern form of balance crane. Ê iixed to the ground (and sometimes attached to the sides of structures as well. Ê 2ower cranes often give the best combination of height and lifting capacity. Ê 2he
ÊAre used in
the construction of tall buildingsÔ
2 ÊA
telescopic crane has a boom that consists of a number of tubes fitted one inside the other.
ÊA
hydraulic or other powered mechanism extends or retracts the tubes to increase or decrease the total length of the boom.
Ê ët
is a type of tower crane.
Ê2hese cranes, also called
self-assembling or "Kangaroo" cranes. ÊLift themselves off
the ground section of the tower to be inserted at ground level or lifted into place by the partially erected crane itself.
"hammerhead" is a fixed-jib crane consisting of a steel-braced tower on which revolves a large, horizontal, double cantilever. Ê 2he
forward part of this cantilever or jib carries the lifting trolley. Ê 2he
jib is extended backwards in order to form a support for the machinery and counter-balancing weight. Ê 2he
D Ê A level luffing crane is
a crane of common design, but with an extra mechanism to keep the hook level when luffing.
Êët is
a crane mechanism where the hook remains at the same level while luffing; moving the jib up and down, so as to move the hook inwards and outwards relative to the base.
Ê A gantry crane has
a hoist in a fixed machinery house or on a trolley that runs horizontally along rails.
Êët is
usually fitted on a single beam (mono-girder) or two beams (twin-girder). Êët is
particularly suited to lifting very heavy objects
Ê Container cranes or
ship-to-shore rail mounted gantry crane is a specialised version of the gantry crane such cranes the horizontal gantry rails and their supporting beam are cantilevered out from between frame uprights spaced to suit the length of a standard freight container Ê ën
Ê Rverhead cranes are also known as
a 'suspended
craneµ ÊAn overhead crane is
a type of crane where the hook-and-line mechanism runs along a horizontal beam that runs along two widely separated rails.
Ê 2hese are used for
cargo operations or boat unloading and retrieval where no shore unloading facilities are available. Ê Most
are diesel-hydraulic or electric-hydraulic.
Ê2he most
advanced form of a deck crane is a GLB deck crane or electro-hydraulic deck cranes it has a robust design, and excellent control and operational properties.
[ Ê 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.
ÊJib cranes are used in
industrial premises and on
military vehicles. ÊMain
types are 0 iloor Mounted Jib Crane 0Wall Mounted Jib Crane 0 Special Application Jib Cranes
£ Ê Bulk-handling cranes are designed from the
outset to carry a shell grab or bucket, rather than using a hook and a sling. Ê2hey are used for bulk cargoes, such
minerals, scrap metal etc.
as coal,
D also called a knuckle-boom crane or articulating crane. Ê ës
ÊA loader crane is
a hydraulically-powered articulated arm fitted to a truck or trailer, and is used for loading/unloading the vehicle. .
Ê A crane with
a forklift type mechanism used in automated (computer controlled) warehouses (known as an automated storage and retrieval system).
Ê2he 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.
V 2his movement of the crane is from one place to another as well as the movement of crane basic work tool. Ê 2ruck-mounted crane Ê Sidelift crane Ê Rough terrain crane Ê All terrain crane Ê Crawler crane Ê Railroad crane Ê iloating crane Ê Aerial crane
2 Ê Cranes mounted on
a rubber tire truck will provide great mobility. Ê2hese cranes are able to
travel on highways, eliminating the need for special equipment to transport the crane.
A sidelifter crane is a road-going truck or semi-trailer. Ê
ÊContainer lift
is done with parallel crane.
Ê A crane mounted on an
undercarriage with four rubber tires that is designed for pick-and-carry operations.
Ê2hese telescopic cranes are single-engine
machines.
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
Ê A crawler is
a crane mounted on an undercarriage with a set of tracks that provide stability and mobility.
Ê 2hey can
lift.
move around on site and perform each
Ê A railroad crane is
a type of crane used on a railroad for one of three primary uses:
0 Handling 0Maintenance 0Accident recovery
Ê iloating cranes are used mainly
in bridge
building and port construction. ÊBut they are
also used for occasional loading and unloading of especially heavy loads on and off ships.
Ê Helicopters used to lift
heavy loads are called
aerial cranes. Ê Helicopters carry
loads connected to long cables or slings in order to place heavy equipments are used.
2 Ê Before moving a load: 0Ensure all loose materials,
parts, blocking and packing have been removed from the load before lifting. 0Make sure that
the lifting device seats in the saddle of the hook.
2hank You
