The first cranes were invented by the Ancient Greeks and were used for constructing high buildings. These cranes were named construction cranes. Larger cranes were later developed to load and unload ships, thus serving the ports. The Industrial Revolution was a milestone, as the cranes were constructed from wood and steel.
A crane is a type of machine which comprises the outriggers, the body, the operator’s cab, the cylinders and the wire ropes. Its outriggers are attached to the vehicle in such a way that all applied forces during load lifting be exerted and keep it on balance. The body also keeps the crane steady, as it is the starting point from which the crane unravels gradually by extending its cylinders.
There are several types of cranes, such as telescopic cranes, construction cranes and mobile cranes (“parrots”). Every such type has completely different equipment.
One of the main features of the telescopic crane is the use of its dead weight as a counterweight to lifting very heavy objects. It is generally considered and classified by Greek authorities as construction equipment. The telescopic crane can lift up to 750 t., but this figure varies of course based on the height and the radius. Some other features are its low travel speed and limited movement during load lifting since its cylinders are not split. Liebherr, Kato, Terex-Demag, Tadano, Grove and Krup own some of the most noteworthy brands worldwide.
The construction crane provides the most common way to lift loads, principally while carrying out projects in road construction and building sites. It is easily disassembled by using telescopic cranes mainly and it can only be moved by trucks. Its basic parts are two latticed structures (horizontal and vertical), acting as counterweights. Construction cranes make use of very heavy concrete slabs. This type of crane cannot move by itself; on the contrary, it remains fixed in place. Liebherr owns the chief brand of construction cranes.
The mobile crane (“parrot”) is the most widely known type of cranes to the public. The machinery is usually mounted on trucks with two, three or even four axles, mostly on the front or the rear part of the vehicle. Furthermore, this crane carries out combined transports. Besides lifting cargo, the mobile crane can carry it over short or long distances in due course as a bonus. Each mobile crane has a different lifting capacity depending on the dead weight of the vehicle to be mounted on. It can also carry out special transports, that is, transport cargo of special dimensions and weights. Effer, Palfinger, Copma and PM own well-known brands of mobile cranes.
All the above types of cranes are equally important as they are largely used in construction and heavy industry.
