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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 10.2, 1-10) and Heron of Alexandria (Mechanica 3.2-5).
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 utilized where the provision of power would be uneconomic.
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.
The device 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.
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.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.The heyday of the crane in ancient times came during the Roman Empire, when construction activity soared and buildings reached enormous dimensions.The first known 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.