A crane is a lifting machine equipped with a winder, wire ropes or chains and sheaves that can be used both to lift and lower materials and to move them horizontally. Wire rope consists of several strands laid (or 'twisted' together like a helix A chain is a series of connected links. This article is about the literal physical chain A sheave (pronounced "shiv" is a wheel or roller with a groove along its edge for holding a belt, Rope or cable. It uses one or more simple machines to create mechanical advantage and thus move loads beyond the normal capability of a human. In Physics, especially Mechanics, a simple machine is a mechanical device that changes the direction or magnitude of a Force. In Physics and Engineering, mechanical advantage (MA is the factor by which a mechanism multiplies the force put into it 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. Transport or transportation is the movement of people and goods from one place to another In the fields of Architecture and Civil engineering, construction is a process that consists of the Building or assembling of Infrastructure Engineering vehicles, known by the other terms construction Equipment, earth movers heavy equipment or just plain equipment are machines specifically designed to execute
Overview
The first cranes were invented by the Ancient Greeks and were powered by men or beasts-of-burden, such as donkeys. The term ancient Greece refers to the period of Greek history lasting from the Greek Dark Ages ca 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. The word Treadmill, originally a type of mill operated by a person treading steps of a wheel to grind grain now designates a piece of indoor sporting equipment for running without 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 High Middle Ages was the period of European history in the 11th 12th and 13th centuries (AD 1000&ndash1299 The earliest cranes were constructed from wood, but cast iron and steel took over with the coming of the Industrial Revolution. Cast iron usually refers to grey cast iron, but identifies a large group of Ferrous Alloys which solidify with a Eutectic. Steel is an Alloy consisting mostly of Iron, with a Carbon content between 0 The Industrial Revolution was a period in the late 18th and early 19th centuries when major changes in agriculture manufacturing and transportation had a profound effect on the
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. This article is about a type of structure For other locational uses see Milldam. A windmill is a machine that is powered by the energy of the wind 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. A steam engine is a Heat engine that performs Mechanical work using Steam as its Working fluid. A steam crane is a crane powered by a Steam engine. It may be fixed or mobile and if mobile it may run on Rail tracks, Caterpillar tracks 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. The internal combustion engine is an engine in which the Combustion of Fuel and an Oxidizer (typically air occurs in a confined space called a An electric motor uses Electrical energy to produce Mechanical energy. For the mechanical technology see Hydraulic machinery and Hydraulic cylinder Hydraulics is a topic of science and Engineering
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, and the largest floating cranes, 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.
History of cranes
Ancient Greek cranes
The crane for lifting heavy loads was invented by the Ancient Greeks in the late 6th century BC. The term ancient Greece refers to the period of Greek history lasting from the Greek Dark Ages ca [1] 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. A Lewis is a category of lifting devices used by Stonemasons to lift large stones into place with a crane, chain block or Winch. 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. [1]
The introduction of the winch and pulley hoist soon lead to a widespread replacement of ramps as the main means of vertical motion. A winch is a mechanical device that is used to pull in (wind up or let out (wind out or otherwise adjust the " Tension " of a Rope or Wire rope A pulley (also called a sheave or block) is a Wheel with a groove between two Flanges around its Circumference This article deals with the physical structure For related terms see Canal inclined plane, Cable railway, Funicular, or Fixed-wing 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 tons. The archaic period in Greece ( 750 BC 480 BC) is a period of Ancient Greek history The Parthenon ( Ancient Greek:) is a temple of the Greek goddess Athena, built in the 5th century BC on the Athenian Acropolis Also, the practice of erecting large monolithic columns was practically abandoned in favour of using several column drums. [2]
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 preferable to the Greek polis than the more labour-intensive ramp which had been the norm in the autocratic societies of Egypt or Assyria. Greece (Ελλάδα transliterated: Elláda, historically, Ellás,) officially the Hellenic Republic (Ελληνική Δημοκρατία A polis ( πόλις, pronunciation, in English-- plural poleis ( πόλεις, pronunciation, in English --is a City, a Ancient Egypt was an Ancient Civilization in eastern North Africa, concentrated along the lower reaches of the Nile River in what is now Early history The most Neolithic site in Assyria is at Tell Hassuna, the center of the Hassuna culture [2]
The first unequivocal literary evidence for the existence of the compound pulley system appears in the Mechanical Problems (Mech. A pulley (also called a sheave or block) is a Wheel with a groove between two Flanges around its Circumference 18, 853a32-853b13) attributed to Aristotle (384-322 BC), but perhaps composed at a slightly later date. Aristotle (Greek Aristotélēs) (384 BC – 322 BC was a Greek philosopher a student of Plato and teacher of Alexander the Great. Around the same time, block sizes at Greek temples began to match their archaic predecessors again, indicating that the more sophisticated compound pulley must have found its way to Greek construction sites by then. [3]
Ancient Roman cranes
The heyday of crane in ancient times came under the Roman Empire, when construction activity soared and buildings reached enormous dimensions. Bonn is the 19th largest city in Germany. Located about 20 kilometres south of Cologne on the river Rhine in the Federal State of North Rhine-Westphalia The Roman Empire was the post-Republican phase of the ancient Roman civilization, characterised by an autocratic form of government and large territorial The Romans adopted the Greek crane and developed it further. We are relatively well informed about their lifting techniques thanks to rather lengthy accounts by the engineers Vitruvius (De Architectura 10. Marcus Vitruvius Pollio (born c 80–70 BC died after c 15 BC was a Roman Writer, Architect and Engineer (possibly praefectus fabrum 2, 1-10) and Heron of Alexandria (Mechanica 3. Hero (or Heron) of Alexandria ( Ήρων ο Αλεξανδρεύς) (c 2-5). There are also two surviving reliefs of Roman treadwheel cranes offering pictorial evidence, with the Haterii tombstone from the late first century AD being particularly detailed. The word Treadmill, originally a type of mill operated by a person treading steps of a wheel to grind grain now designates a piece of indoor sporting equipment for running without Quintus Haterius (d 27 was a member of a Roman Empire senatorial family
The simplest Roman crane, the Trispastos, consisted of a single-beam jib, a winch, a rope, and a block containing three pulleys. A winch is a mechanical device that is used to pull in (wind up or let out (wind out or otherwise adjust the " Tension " of a Rope or Wire rope A rope is a length of Fibers twisted or Braided together to improve strength for pulling and Connecting. Having thus a mechanical advantage of 3:1, it has been calculated that a single man working the winch could raise 150 kg (3 pulleys x 50 kg = 150), assuming that 50 kg represent the maximum effort a man can exert over a longer time period. In Physics and Engineering, mechanical advantage (MA is the factor by which a mechanism multiplies the force put into it 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. The Egyptian pyramids are pyramid shaped structures located in Egypt, and were built as a tomb for dead pharaohs 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). [4]
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 architraves blocks weigh up to 60 tons each, and the corner cornices blocks even over 100 tons, all of them raised to a height of ca. Baalbek (بعلبك is a town in the Bekaa Valley of Lebanon, altitude 1170 m (3850 ft situated east of the Litani River. The architrave (also called epistyle or door frame) is a moulded or ornamental band framing a rectangular opening 19 m above the ground. [3] In Rome, the capital block of Trajan's Column weighs 53. Rome ( Roma ˈroma Roma is the capital city of Italy and Lazio, and is Italy's largest and most populous city with more than 2 Trajan's Column is a Monument in Rome raised in honour of the Roman emperor Trajan and constructed by the architect Apollodorus of Damascus 3 tons which had to be lifted at a height of ca. 34 m. [5]
It is assumed that Roman engineers accomplished lifting these extraordinary weights by two measures: 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. A siege tower (or in the Middle Ages a Belfry) is a specialized Siege engine, constructed to protect assailants and ladders while approaching 5). [6] 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). A capstan is a rotating machine used to apply Force to another element notably used on board ship and on dock walls for heaving-in or veering ropes cables and hawsers [7] This use of multiple capstans is also described by Ammianus Marcellinus (17. Amiricanus Gambilinus (325/330-after 391 was a fourth-century Roman historian. 4. 15) in connection with the lifting of the Lateranense obelisk in the Circus Maximus (ca. There are eight Ancient Egyptian and five ancient Roman obelisks in Rome, together with a number of more modern Obelisks there was also formerly (until 2005 The Circus Maximus ( Latin for greatest circus, in Italian Circo Massimo) is an ancient Hippodrome and mass entertainment 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. [8] Lifting such heavy weights in a concerted action required a great amount of coordination between the work groups applying the force to the capstans.
Medieval cranes
During the High Middle Ages, the treadwheel crane was reintroduced on a large scale after the technology had fallen into disuse in western Europe with the demise of the Western Roman Empire. The High Middle Ages was the period of European history in the 11th 12th and 13th centuries (AD 1000&ndash1299 The Western Roman Empire refers to the western half of the Roman Empire, from its division by Diocletian in 285 the other half of the Roman Empire was the Eastern [9] The earliest reference to a treadwheel (magna rota) reappears in archival literature in France about 1225,[10] followed by an illuminated depiction in a manuscript of probably also French origin dating to 1240. [9] In navigation, the earliest uses of harbor cranes are documented for Utrecht in 1244, Antwerp in 1263, Brugge in 1288 and Hamburg in 1291,[11] while in England the treadwheel is not recorded before 1331. Utrecht ( city and municipality is the capital and most populous city of the Dutch province of Utrecht. ||-||-||-||} Antwerp ( Dutch:, French: Anvers) is a City and Municipality in Belgium and the capital of the Bruges (Brugge is the capital and largest city of the province of West Flanders in the Flemish Region of Belgium. Hamburg (English, German: ˈhambʊɐk local pronunciation Low German / Low Saxon: Hamborg) is the second-largest city in Germany [12]
Generally, vertical transport was done safer and cheaper 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. See also Gothic art Gothic architecture is a style of Architecture which flourished during the high and late medieval period. 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. A wheelbarrow is a small hand-propelled vehicle usually with just one Wheel, designed to be pushed and guided by a single person using two handles to the rear or a sail A ladder is a vertical or inclined set of rungs or steps. There are two types rigid ladders that can be leaned against a vertical surface such as a Wall, and A brick hod is a three-sided box for carrying Bricks or other construction materials, often mortar. Rather, old and new machinery continued to coexist on medieval construction sites[13] and harbors. [11]
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. A spoke is one of some number of rods radiating from the center of a Wheel (the hub where the Axle connects connecting the hub with the round traction surface A crank is an arm at right angles to a shaft (an Axle or spindle by which motion is imparted to or received from the shaft it is also used to change circular into Reciprocating The wheel of a Ship is the modern method of adjusting the angle of the Rudder, in turn changing the direction of the Boat or Ship. 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. A flywheel is a mechanical device with significant Moment of inertia used as a storage device for Rotational energy. [14]
Origins
The exact process by which the treadwheel crane was reintroduced is not recorded,[10] 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. A windlass is an apparatus for moving heavy weights Typically a windlass consists of a horizontal cylinder (barrel which is rotated by the turn of a crank or belt 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. Marcus Vitruvius Pollio (born c 80–70 BC died after c 15 BC was a Roman Writer, Architect and Engineer (possibly praefectus fabrum De architectura ( Latin: "On architecture" is a treatise on Architecture written by the Roman Architect Vitruvius Its reintroduction may have been inspired, as well, by the observation of the labor-saving qualities of the waterwheel with which early treadwheels shared many structural similarities. A water wheel is a means of extracting power from the flow (or fall of water otherwise known as Hydropower. [12]
Structure and placement
The medieval treadwheel was a large wooden wheel turning around a central shaft with a treadway wide enough for two workers walking side by side. An axle is a central shaft for a rotating Wheel or Gear. In some cases the axle may be fixed in position with a bearing or Bushing 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,[15] giving the possibility of using a thinner shaft and providing thus a greater mechanical advantage. [16]
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. Scaffolding is a temporary framework used to support people and material in the construction or repair of buildings and other large structures 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. [17] Thus, the crane ‘grew’ and ‘wandered’ with the building with the result that today all extant construction cranes in England are found in church towers above the vaulting and below the roof, where they remained after building construction for bringing material for repairs aloft. [18]
Less frequently, medieval illuminations also show cranes mounted on the outside of walls with the stand of the machine secured to putlogs. [19]
Mechanics and operation
In contrast to modern cranes, medieval cranes and hoists - much like their counterparts in Greece and Rome[20] - were primarily capable of a vertical lift, and not used to move loads for a considerable distance horizontally as well. [17] 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,[17] 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. [20] 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. [21] Slewing cranes which allowed a rotation of the load and were thus particularly suited for dockside work appeared as early as 1340. [22] 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. A pallet (ˈpæːlɨt (sometimes called a skid) is a flat transport structure that supports goods in a stable fashion while being lifted by a Forklift, Pallet A basket is a container which is traditionally constructed from stiff fibres often made of Willow. A barrel or cask is a hollow cylindrical container traditionally made of Wood Staves and bound with Iron Hoops The [23]
It is noteworthy that medieval cranes rarely featured ratchets or brakes to forestall the load from running backward. In Mechanical engineering, a ratchet is a device that allows linear or rotary motion in only one direction while preventing motion in the opposite direction A brake is a device for slowing or stopping the motion of a Machine or Vehicle, or alternatively a device to restrain it from starting to move again [24] This curious absence is explained by the high friction force exercised by medieval treadwheels which normally prevented the wheel from accelerating beyond control. Friction is the Force resisting the relative motion of two Surfaces in contact or a surface in contact with a fluid (e [21]
Harbor cranes
According to the “present state of knowledge” unknown in antiquity, stationary harbor cranes are considered a new development of the Middle Ages. [11] 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. A seesaw (also known as a teeter-totter) is a long narrow board suspended in the middle so that as one end goes up the other goes down A winch is a mechanical device that is used to pull in (wind up or let out (wind out or otherwise adjust the " Tension " of a Rope or Wire rope A yard is a Spar on a mast from which Sails are set It may be constructed of timber steel or from more modern materials like Aluminum or [11]
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. [25] Interestingly, dockside cranes were not adopted in the Mediterranean region and the highly developed Italian ports where authorities continued to rely on the more labor-intensive method of unloading goods by ramps beyond the Middle Ages. [26]
Unlike construction cranes where the work speed was determined by the relatively slow progress of the masons, harbor cranes usually featured double treadwheels to speed up loading. The two treadwheels whose diameter is estimated to be 4 m or larger were attached to each side of the axle and rotated together. [11] Today, according to one survey, fifteen treadwheel harbor cranes from pre-industrial times are still extant throughout Europe. [27] Beside these stationary cranes, floating cranes which could be flexibly deployed in the whole port basin came into use by the 14th century. A crane vessel, crane ship or floating crane is a Ship that is specialized in lifting heavy loads [25]
Mechanical principles
There are two major considerations that are taken into account in the design of cranes. Barcelona ( Catalan bəɾsəˈlonə Spanish baɾθeˈlona is the capital and most populous city of the Autonomous Community of Catalonia Spain () or the Kingdom of Spain (Reino de España is a country located mostly in southwestern Europe on the Iberian Peninsula. The first is that the crane must be able to lift a load of a specified weight and the second is that the crane must remain stable and not topple over when the load is lifted and moved to another location.
Lifting capacity
Cranes illustrate the use of one or more simple machines to create mechanical advantage. In Physics, especially Mechanics, a simple machine is a mechanical device that changes the direction or magnitude of a Force. In Physics and Engineering, mechanical advantage (MA is the factor by which a mechanism multiplies the force put into it
- The lever. A balance crane contains a horizontal beam (the lever) pivoted about a point called the fulcrum. 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. In Physics, a force is whatever can cause an object with Mass to Accelerate. 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. In Physics and Engineering, mechanical advantage (MA is the factor by which a mechanism multiplies the force put into it
- The pulley. A pulley (also called a sheave or block) is a Wheel with a groove between two Flanges around its Circumference 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. 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.
- The hydraulic cylinder. For the mechanical technology see Hydraulic machinery and Hydraulic cylinder Hydraulics is a topic of science and Engineering This can be used directly to lift the load or indirectly to move the jib or beam that carries another lifting device.
Cranes, like all machines, obey the principle of conservation of energy. In Physics, the law of conservation of energy states that the total amount of Energy in an isolated system remains constant and cannot be created although it may This means that the energy delivered to the load cannot exceed the energy put into the machine. In Physics and other Sciences energy (from the Greek grc ἐνέργεια - Energeia, "activity operation" from grc ἐνεργός 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). Friction is the Force resisting the relative motion of two Surfaces in contact or a surface in contact with a fluid (e In Thermodynamics, the thermal efficiency (\eta_{th} \ is a dimensionless performance measure of a thermal device such as an Internal combustion
Stability of crane
In order for a crane to be stable, the sum of all moments about any point such as the base of the crane must equate to zero. In Physics, the moment of force (often just moment, though there are other quantities of that name such as Moment of inertia) is a Pseudovector 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.
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.
Standards for cranes mounted on ships or offshore platforms are somewhat stricter due to 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.
Types of cranes
Railroad cranes
A railroad crane is a crane with flanged wheels, used by railroads. A railroad crane, ( crane car (US or breakdown crane (UK is a type of crane used on a railroad for one of three primary The simplest form is just a crane mounted on a railroad car or on a flatcar. A railroad car or railway carriage is a Vehicle on a rail transport system (railroad or railway that is used for the carrying of Cargo or A flatcar (also flat car) is a piece of Railroad rolling stock that consists of an open flat deck on four or six wheels or a pair of trucks (US or More capable devices are purpose-built.
Different types of crane are used for maintenance work, recovery operations and freight loading in goods yards. MOW redirects here For other meanings see MOW (disambiguation.
Mobile crane
The most basic type of mobile crane consists of a steel truss or telescopic boom mounted on a mobile platform, which may be rail, wheeled (including "truck" carriers) or caterpillar tracks. Steel is an Alloy consisting mostly of Iron, with a Carbon content between 0 In Architecture and Structural engineering, a truss is a structure comprising one or more triangular units constructed with straight slender members whose This article is about the semi-truck For the North American use of the word see Pickup truck. Continuous tracks are large (modular tracks used on the so-called caterpillar Tanks construction equipment and certain other off-road vehicles The boom is hinged at the bottom, and can be raised and lowered by cables or by hydraulic cylinders. A hook is suspended from the top of the boom by wire rope and sheaves. A sheave (pronounced "shiv" is a wheel or roller with a groove along its edge for holding a belt, Rope or cable. The wire ropes are operated by whatever prime movers the designers have available, operating through a variety of transmissions. Steam engines, electric motors and internal combustion engines (IC) have all been used. A steam engine is a Heat engine that performs Mechanical work using Steam as its Working fluid. An electric motor uses Electrical energy to produce Mechanical energy. The internal combustion engine is an engine in which the Combustion of Fuel and an Oxidizer (typically air occurs in a confined space called a Older cranes' transmissions tended to be clutches. A clutch is a mechanism for transmitting rotation which can be engaged and disengaged This was later modified when using IC engines to match the steam engines "max torque at zero speed" characteristic by the addition of a hydrokinetic element culminating in controlled torque converters. A torque converter is a modified form of Fluid coupling that is used to transfer rotating power from a prime mover, such as an Internal combustion engine The operational advantages of this arrangement can now be achieved by electronic control of hydrostatic drives, which for size and other considerations is becoming standard. Some examples of this type of crane can be converted to a demolition crane by adding a demolition ball, or to an earthmover by adding a clamshell bucket or a dragline and scoop, although design details can limit their effectiveness. Demolition is the opposite of Construction: the tearing-down of Buildings and other Structures It contrasts with deconstruction Engineering vehicles, known by the other terms construction Equipment, earth movers heavy equipment or just plain equipment are machines specifically designed to execute Dragline excavation systems are Heavy equipment used in Civil engineering and surface Mining.
To increase the horizontal reach of the hoist, the boom may be extended by adding a jib to the top. The jib can be fixed or, in more complex cranes, luffing (that is, able to be raised and lowered).
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. For the mechanical technology see Hydraulic machinery and Hydraulic cylinder Hydraulics is a topic of science and Engineering 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.
Tower crane
The tower crane is a modern form of balance crane. Fixed to the ground (or "jacked up" and supported by the structure as the structure is being built), tower cranes often give the best combination of height and lifting capacity and are used in the construction of tall buildings. To save space and to provide stability the vertical part of the crane is often braced onto the completed structure which is normally the concrete lift shaft in the center of the building. A horizontal boom is balanced asymmetrically across the top of the tower. Its short arm carries a counterweight of concrete blocks, and its long arm carries the lifting gear. Concrete is a construction material composed of Cement (commonly Portland cement) as well as other cementitious materials such as Fly ash and Slag The crane operator either sits in a cabin at the top of the tower or controls the crane by radio remote control from the ground, usually standing near the load. In the first case the operator's cabin is located at the top of the tower just below the horizontal boom. The boom is mounted on a slewing bearing and is rotated by means of a slewing motor. The lifting hook is operated by a system of sheaves. A lifting hook is a device for grabbing and lifting loads by means of a device such as a hoist or crane. A sheave (pronounced "shiv" is a wheel or roller with a groove along its edge for holding a belt, Rope or cable.
A tower crane is usually assembled by a telescopic jib crane of smaller lifting capacity but greater height and in the case of tower cranes that have risen while constructing very tall skyscrapers, a smaller crane (or derrick) will sometimes be lifted to the roof of the completed tower to dismantle the tower crane afterwards. A self-assembling tower crane lifts itself off the ground using jacks, allowing the next section of the tower to be inserted at ground level. It is often claimed that a large fraction of the tower cranes in the world are in use in Dubai. Dubai (in دبيّ,) is one of the seven emirates and most populous city of the United Arab Emirates (UAE The exact percentage remains an open question. [28]
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. A cantilever is a beam supported on only one end The beam carries the load to the support where it is resisted by moment and Shear stress. A jib (also spelled jibb) is a triangular Staysail set ahead of the foremost mast of a sailing boat A cantilever is a beam supported on only one end The beam carries the load to the support where it is resisted by moment and Shear stress. A jib (also spelled jibb) is a triangular Staysail set ahead of the foremost mast of a sailing boat 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. Hammerhead cranes are generally constructed in large sizes, up to 350 tons.
The design evolved first in Germany around the turn of the 19th century and was adopted for use in British shipyards to support the battleship construction program from 1904-1914. The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom, the UK or Britain,is a Sovereign state located Shipyards and dockyards are places which repair and build ships These can be Yachts military Year 1904 ( MCMIV) was a Leap year starting on Friday (link will display calendar of the Gregorian calendar (or a Leap year starting on Year 1914 ( MCMXIV) was a Common year starting on Thursday (link will display the full calendar of the Gregorian calendar (or a Common year The ability of the hammerhead crane to lift heavy weights was useful for installing large pieces of battleships such as armour plate and gun barrels. A battleship is a large heavily armored Warship with a main battery consisting of the largest Calibre of Guns Battleships were For body armour see Armour, for armoured forces see Armoured warfare, for other uses see Armour (disambiguation. A gun is a particular Weapon that propels Projectiles The projectile is generally fired through a hollow tube known as the gun's barrel. Hammerhead cranes were also installed in naval shipyards in Japan and in the USA. For a topic outline on this subject see List of basic Japan topics. The United States of America —commonly referred to as the The British Government also installed a hammerhead crane at the Singapore Naval Base (1938) and later a copy of the crane was installed at Garden Island Naval Dockyard in Sydney (1951). Singapore Year 1938 ( MCMXXXVIII) was a Common year starting on Saturday (link will display the full calendar of the Gregorian calendar. Sydney (ˈsɪdniː is the most populous city in Australia, with a Metropolitan area population of approximately 4 Year 1951 ( MCMLI) was a Common year starting on Monday. Events of 1951 January These cranes provided repair support for the battle fleet operating far from Great Britain. See also Kingdom of Great Britain Great Britain (Breatainn Mhòr Prydain Fawr Breten Veur Graet Breetain is the larger of the two main islands
The principal engineering firm for hammerhead cranes in the British Empire was Sir William Arrol & Co Ltd.
Truck-mounted crane
A crane mounted on a truck carrier provides the mobility for this type of crane. This article is about the semi-truck For the North American use of the word see Pickup truck.
Generally, these cranes are designed to be able to travel on streets and highways, eliminating the need for special equipment to transport a crane to the jobsite. When working on the jobsite, outriggers are extended horizontally from the chassis then down vertically to level and stabilize the crane while stationary and hoisting. An outrigger is a part of a boat's Rigging which is rigid and extends beyond the side or Gunwale of a boat A hoist is a device used for lifting or lowering a load by means of a drum or lift-wheel around which rope or chain wraps Many truck cranes possess limited slow-travelling capability (just 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 of the anti-tipping stability then lies in the strength and stiffness of the chassis suspension. Most cranes of this type also have moving counterweights for stabilization beyond that of the outriggers. Loads suspended directly over the rear remain more stable, as most of the weight of the truck crane itself then acts as a counterweight to the load. Factory-calculated charts (or electronic safeguards) are used by the crane operator to determine the maximum safe loads for stationary (outriggered) work as well as (on-rubber) loads and travelling speeds.
Truck cranes range in lifting capacity from about 14. 5 US tons to about 1300 US tons.
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 that extend horizontally and vertically are used to level and stabilize the crane for hoisting.
These telescopic cranes are single-engine machines where the same engine is used for powering the undercarriage as is used for powering the crane, similar to a crawler crane. However, in a rough terrain crane, the engine is usually mounted in the undercarriage rather than in the upper, like the crawler crane.
All Terrain Crane (AT's)
A mobile crane which has the necessary equipment to travel with high speed on public roads/highways and on the job site in rough terrain with all wheel and crab steering. AT‘s combine the roadability of Truck-mounted Crane and the manoeuvrability of a Rough Terrain Crane.
AT’s have 2-9 axles and are designed for lifting loads up to 1200[29] metric tons. This article is about the tonne or metric ton For other tons see Ton.
Crawler crane
A crawler is a crane mounted on an undercarriage with a set of tracks (also called crawlers)that provide for the stability and mobility of the crane. Crawler cranes have both advantages and disadvantages depending on their intended use. The main advantage of a crawler is that they can move on site and perform lifts with very little set-up, as 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 of a crawler crane is that they are very heavy, and cannot easily be moved from one job site to the next without significant expense. Typically, a large crawler must be disassembled and moved by trucks, rail cars or ships to be transported to its next location.
Crawler cranes range in lifting capacity from about 40 US tons to 3500 US tons.
Gantry crane
A gantry crane has a hoist in a trolley which runs horizontally along gantry rails, usually fitted underneath a beam spanning between uprights which themselves have wheels so that the whole crane can move at right angles to the direction of the gantry rails. Both overhead travelling cranes and gantry cranes are types of crane which lift objects by a hoist which is fitted in a trolley and can move A hoist is a device used for lifting or lowering a load by means of a drum or lift-wheel around which rope or chain wraps 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 after the first manufacturer), designed for loading and unloading ship-borne containers at a port. A container crane (also known as a portainer, container handling gantry crane, quay crane, ship-to-shore crane, ship-to-shore gantry crane
Overhead crane
Also known as a "suspended crane", this type of crane works in the same way as a gantry crane but without uprights. Both overhead travelling cranes and gantry cranes are types of crane which lift objects by a hoist which is fitted in a trolley and can move The hoist is on a trolley which moves in one direction along one or two beams, which move at right angles to that direction along elevated tracks, often mounted along the side walls of an assembly area in a factory. A hoist is a device used for lifting or lowering a load by means of a drum or lift-wheel around which rope or chain wraps A factory (previously manufactory) or manufacturing plant is an industrial Building where workers manufacture goods Some of them can lift very heavy loads.
Floating crane
Floating cranes are used mainly in bridge building and port construction, but they are also used for occasional loading and unloading of especially heavy or awkward loads on and off ships. The SSCV Thialf is a semi-submersible crane vessel. It was constructed in 1985 as DB-102 for McDermott by Mitsui Engineering & Shipbuilding Co A bridge is a Structure built to span a Gorge, Valley, Road, railroad track, River, Body of water ||-||-|-||-||-||-||-||-||-|} A port is a facility for receiving Ships and transferring cargo Some floating cranes are mounted on a pontoon, others are specialized crane barges with a lifting capacity exceeding 10,000 tons and have been used to transport entire bridge sections. A pontoon is a flat-bottomed Boat or the floats used to support a structure on water BARGE, the Big August RecGambling Excursion is a yearly convention held in Las Vegas during the first weekend of August Units of mass There are three similar units of Mass called the ton: Long ton (simply ton in countries such as the United Floating cranes have also been used to salvage sunken ships. A ship /ʃɪp/ is a large vessel that floats on water Ships are generally distinguished from Boats based on size
Crane vessels are often used in offshore construction. A crane vessel, crane ship or floating crane is a Ship that is specialized in lifting heavy loads Offshore construction is the installation of structures and pipelines in a marine environment for the production and transmission of oil and Gas. The largest revolving cranes can be found on SSCV Thialf, which has two cranes with a capacity of 7,100 metric tons each. The SSCV Thialf is a semi-submersible crane vessel. It was constructed in 1985 as DB-102 for McDermott by Mitsui Engineering & Shipbuilding Co This article is about the tonne or metric ton For other tons see Ton.
Uglen is another, smaller crane vessel.
Vessel (Deck) crane
Located on the ships and used for cargo operations where no shore unloading facilities are available. Most are diesel-hydraulic or electric-hydraulic.
Aerial crane
Aerial cranes usually extend from helicopters to lift large loads. One of the most unusual commercial uses of Helicopters is the aerial crane or skycrane. History Since 400 AD Chinese children have played with bamboo flying toys. Helicopters are able to travel to and lift in areas that are more difficult to reach by a conventional crane. Aerial helicopter cranes are most commonly used to lift units/loads onto shopping centers, multi-story buildings, highrises, etc. However, they can lift basically anything within their lifting capacity, (i. e. cars, boats, swimming pools, etc. ). They also work as disaster relief after natural disasters for clean-up, and during wild-fires they are able to carry huge buckets of water over fires to put them out.
Examples include:
- Sikorsky S-64 Skycrane/Erickson Air Crane - civilian version
- CH-54 Tarhe - military version
- Mi-26 - Russian flying crane helicopter
- 234 Chinook - Boeing Helicopters/Columbia Helicopters tandem rotor heavy lift
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.
Crane-like 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:
More technically-advanced types of such lifting machines are often known as 'cranes', regardless of the official definition of the term. A block and tackle is a system of two or more Pulleys with a Rope or Cable threaded between them usually used to lift or pull heavy loads A capstan is a rotating machine used to apply Force to another element notably used on board ship and on dock walls for heaving-in or veering ropes cables and hawsers A hoist is a device used for lifting or lowering a load by means of a drum or lift-wheel around which rope or chain wraps A winch is a mechanical device that is used to pull in (wind up or let out (wind out or otherwise adjust the " Tension " of a Rope or Wire rope A windlass is an apparatus for moving heavy weights Typically a windlass consists of a horizontal cylinder (barrel which is rotated by the turn of a crank or belt Some notable examples follow:
Loader crane
A loader crane (also called a knuckle-boom crane) is a hydraulically-powered articulated arm fitted to a truck or trailer, and is used for loading/unloading the vehicle. Autoclaved Aerated Concrete (AAC or otherwise known as Autoclave Cellular Concrete (ACC is a lightweight precast building material This article is about the semi-truck For the North American use of the word see Pickup truck. A Trailer is generally an unpowered vehicle pulled by a powered 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, this type of crane is almost invariably 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. Hydrauliska Industri AB ( Hiab) is a Finnish manufacturer of loader cranes demountable containers forestry cranes truck-mounted Forklifts and
Rolloader crane
This 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.
Manufacturer of rolloader cranes include the Dutch Kennis [1] and the Finnish company Hiab (Hydrauliska Industri AB). Kennis Music is a Record label, specializing in R&B, pop and Hip-hop music founded by popular Nigerian radio DJ Kenny Finland, officially the Republic of Finland ( is a Nordic country situated in the Fennoscandian region of northern Europe. Hydrauliska Industri AB ( Hiab) is a Finnish manufacturer of loader cranes demountable containers forestry cranes truck-mounted Forklifts and
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)). A warehouse is a commercial Building for Storage of Goods. Warehouses are used by Manufacturers Importers Exporters Automated Storage and Retrieval Systems (often referred to as ASRS or AS/RS refers to a variety of computer-controlled methods for automatically depositing and retrieving loads from defined 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. The product can in some cases be as large as an automobile. Stacker cranes are often used in the large freezer warehouses of frozen food manufacturers. This automation avoids requiring forklift drivers to work in below freezing temperatures every day.
Sidelift
A sidelift is a road going truck or semi-trailer that is used to hoist and transport ISO standard containers. This article is about the semi-truck For the North American use of the word see Pickup truck. In American English a semi-trailer is a trailer without a front axle Containerization (or containerisation) is a system of Intermodal freight transport Cargo Transport using standard ISO containers Lifting of containers is achieved through the use of parallel crane like hoists, which can be used to lift a container from the ground, or from a railway vehicle. "Railroad" and "Railway" both redirect here For other uses see Railroad (disambiguation.
Cranes of special interest
- Finnieston Crane (aka the Stobcross Crane)
- – Category A -listed example of a 'hammerhead' (cantilever) crane in Glasgow's former docks
- – 50m tall, 175 tons capacity, built 1926
- Kockums Crane
- – shipyard crane formerly at Kockums, Sweden. Purpose Connected to a spur of the Stobcross Railway, the crane's primary purpose was to lift massive Boilers and Engines onto new ships at the time A listed building in the United Kingdom is a building or other structure officially designated as being of special architectural historical or cultural significance Glasgow (ˈglæzgoʊ is the largest city in Scotland and third most populous in the United Kingdom The Kockums Crane (or Kockumskranen in Swedish) was a 138-metre-tall crane, formerly of the Swedish shipyard Kockums in Malmö Kockums AB is a Shipyard in Malmö, Sweden owned by the German shipyard HDW in Kiel. "Sverige" redirects here For other uses see Sweden (disambiguation and Sverige (disambiguation.
- – 138m tall, 1500 tonne capacity, since moved to Ulsan, South Korea
- Samson and Goliath (cranes)
- – two gantry cranes at the Harland & Wolff shipyard in Belfast
- – Goliath is 96m tall, Samson is 106m
- – span 140m, lift-height 70m, capacity 840 tonnes each (1600 tonnes combined)
- Breakwater Crane Railway
- – self-propelled steam crane that formerly ran the length of the breakwater at Douglas
- – ran on 10 feet (3. Ulsan is a metropolitan city in the south-east of South Korea, facing the East Sea South Korea, officially the Republic of Korea and often referred to as Korea ( Korean: 대한민국 tɛː Samson and Goliath are twin Shipbuilding Gantry cranes situated at Queen's Island Belfast, Northern Ireland. Both overhead travelling cranes and gantry cranes are types of crane which lift objects by a hoist which is fitted in a trolley and can move Harland and Wolff Heavy Industries is a diversified heavy industrial company specialising in Shipbuilding, Ship breaking, Offshore construction Belfast ( is the capital city of Northern Ireland and the seat of government in Northern Ireland. The Douglas Breakwater Crane Railway was a massive self-propelled steam crane that ran the length of the original breakwater at Douglas, for the loading and unloading 05 m) gauge track, the broadest in the British Isles
Manufacturers
Major manufacturers of cranes include:
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Historic
Manufacturers that have now ceased trading as a separate entity:
- Abell-Howe (Now a division of Columbus McKinnon)
- Dresser Industries (Merged with Halliburton)
- Euclid Renamed to Terex by GM in 1957
- Gallion
- Gaffey (Now a division of Columbus McKinnon)
- Grove (Now part of Manitwoc Crane Group)
- Isringhausen (Sold to Hulcher Services)
- Jaeger Machine Company (Out of business by 1973)
- Koehring Cranes (Now a subsidiary of Terex)
- Pettibone Manufacturing (No longer offers Cranes)
- National Crane (Now part of Manitwoc Crane Group)
- Ransomes & Rapier
- Shawbox (Now a division of Columbus McKinnon)
- Wright (Now a part of ACCO Material Handling Solutions)
- Yale Hoists (Now a division of Columbus McKinnon)
References
- ^ a b J. is one of the largest Keiretsus ' founded by Masatomo Sumitomo. Terex Corporation is a diversified global manufacturer of a broad range of Heavy equipment for a variety of industries including construction infrastructure quarrying Dresser Industries was a Multinational corporation headquartered in Dallas, Texas, which provided a wide range of technology products and services used Halliburton Energy Services ( is a US -based Multinational corporation with operations in more than 70 countries Euclid ( Greek:.) fl 300 BC also known as Euclid of Alexandria, is often referred to as the Father of Geometry Neopets (originally NeoPets) is a virtual pet Website launched by Adam Powell and Donna Williams on 15 November 1999 Terex Corporation is a diversified global manufacturer of a broad range of Heavy equipment for a variety of industries including construction infrastructure quarrying Ransomes Sims and Jeffries Engineers of Ipswich were a major British agricultural machinery maker J. Coulton, p. 7
- ^ a b J. J. Coulton, p. 14f.
- ^ a b J. J. Coulton, p. 16
- ^ All data from: Hans-Liudger Dienel, Wolfgang Meighörner, p. 13
- ^ Lynne Lancaster, p. 426
- ^ Lynne Lancaster, p. 427ff.
- ^ Lynne Lancaster, p. 434ff.
- ^ Lynne Lancaster, p. 436
- ^ a b Andrea Matthies, p. 514
- ^ a b Andrea Matthies, p. 515
- ^ a b c d e Michael Matheus, p. 345
- ^ a b Andrea Matthies, p. 524
- ^ Andrea Matthies, p. 545
- ^ Andrea Matthies, p. 518
- ^ Andrea Matthies, p. 525f.
- ^ Andrea Matthies, p. 536
- ^ a b c Andrea Matthies, p. 533
- ^ Andrea Matthies, p. 532ff.
- ^ Andrea Matthies, p. 535
- ^ a b J. J. Coulton, p. 6
- ^ a b Hans-Liudger Dienel, Wolfgang Meighörner, p. 17
- ^ Andrea Matthies, p. 534
- ^ Andrea Matthies, p. 531
- ^ Andrea Matthies, p. 540
- ^ a b Michael Matheus, p. 346
- ^ Michael Matheus, p. 347
- ^ These are Bergen, Stockholm, Karlskrona (Sweden), Kopenhagen (Denmark), Harwich (England), Danzig, Lüneburg, Stade, Otterndorf, Marktbreit, Würzburg, Östrich, Bingen, Andernach and Trier (Germany). Cf. Michael Matheus, p. 346
- ^ Debunking Dubai. ENR (2000-11-05). 2000 ( MM) was a Leap year that started on Saturday of the Common Era, in accordance with the Gregorian calendar. Events 1499 - Publication of the Catholicon in Treguier ( Brittany) Retrieved on 2008-05-05. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 553 - The Second Council of Constantinople begins 1215 - Rebel Barons renounce their allegiance to King John
- ^ LTM11200-9.1. Liebherr. Retrieved on 2008-06-01. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 193 - Roman Emperor Didius Julianus is Assassinated 987 - Hugh Capet is elected
Literature
History of cranes
- Andrea Matthies: Medieval Treadwheels. Artists' Views of Building Construction, Technology and Culture, Vol. 33, No. 3 (Jul. , 1992), pp. 510-547
- Hans-Liudger Dienel, Wolfgang Meighörner, “Der Tretradkran,“ Publication of the Deutsches Museum (Technikgeschichte Series), 2nd ed. , München 1997
- J. J. Coulton, “Lifting in Early Greek Architecture,” The Journal of Hellenic Studies, Vol. 94. (1974), pp. 1-19
- Lynne Lancaster, “Building Trajan's Column,” American Journal of Archaeology, Vol. 103, No. 3. (Jul. , 1999), pp. 419-439
- Michael Matheus: "Mittelalterliche Hafenkräne," in: Uta Lindgren (ed. ): Europäische Technik im Mittelalter. 800-1400, Berlin 2001 (4th ed. ), pp. 345-48 ISBN 3-7861-1748-9
See also
- Banksman
- Pallet
- Steam shovel
- National Association of Heavy Equipment Training Schools – US educational organisation
- Naval lifting devices with one, two, and three legs: derrick, sheers, and gyn
Related ideas
External links
In British Civil engineering, a banksman is the skilled person who directs the operation of a crane from the point near where loads are attached and detached A pallet (ˈpæːlɨt (sometimes called a skid) is a flat transport structure that supports goods in a stable fashion while being lifted by a Forklift, Pallet A steam shovel is a large steam-powered excavating machine designed for lifting and moving material such as rock and Soil. The National Association of Heavy Equipment Training Schools (NAHETS founded 2005 is an association of heavy equipment operator training schools in the United States. A derrick is a lifting device composed of one mast or pole which is hinged freely at the bottom Sheers are a form of two-legged lifting device that were used by Sailboats and Dockyards for tasks such as lifting Masts and heavier parts of the Rigging A gyn is a form of three legged lifting device used on Sailboats It provides more stability than a Derrick or Sheers, and requires no Rigging Skyhooks are a type of hypothetical structure that would be used for Non-rocket spacelaunch into Orbit, for example a Space elevator, continuously supportingDapyx Software network: MP3 Explorer | Ebook Manager | Zenithic