Examples of cranes throughout history

by newportcomputers on January 17, 2013

Simple cranes have been around for thousands of years. The ancient Egyptians employed wooden called ‘shadufs’ to raise irrigation water from the Nile and some archaeologists believe similar devices were used in the building of the pyramids.

Early cranes
The ancient Greeks also used cranes and are credited with inventing the first large cranes, which they used to raise heavy stone blocks into place when constructing their temples. Evidence has been found of ‘lewis holes’, which are particular-shaped holes cut in stone blocks in order to lift them with a crane.
It is believed that as the great dynasties of ancient Egypt and Greece began to die out, the need for giant monoliths erected with ramps and brute manpower also died with them. They were replaced by smaller construction crews using winches and hoists to manoeuvre more practical-sized stone blocks into place in their buildings and temples.
Roman cranes
Cranes were employed extensively in the construction of the Roman Empire. The Roman’s most simple lifting device was a called a ‘trispastos’, which consisted of a jib, a winch, a block of pulleys and a rope.
The amount of mechanical advantage was varied by the number of pulleys used, with the largest trispastos employing a tread-wheel, which hoisted the load aloft as a slave walked inside the wheel. To raise even heavier loads, the Romans built lifting towers, which it could be argued were the forerunners of the tower cranes we know today.
Medieval cranes
During the Middle Ages, tread-wheel cranes were used to construct large buildings such as castles and cathedrals and also on the docks to lift cargo from the holds of ships. The development of the windlass (horizontal cylinder turned by a crank) and the flywheel (revolving wheel that smoothes the lifting process) saw these early cranes start to become much more sophisticated.
Industrial Revolution
Traditionally made from wood, cranes began to be constructed from cast iron and steel as the Industrial Revolution got under way in the 19th century. While early cranes were powered by men or animals, the invention of the steam engine saw steam-powered cranes come into existence. These were cranes with a boiler mounted on the back that acted as a counterbalance  for the load being lifted by the jib. Steam cranes were often mounted on trolleys, rails or barges and were commonly used as breakdown cranes on the early railways.
Today’s cranes
The cranes of today have come a long way from their predecessors. Formerly powered by brute force, they are now powered by internal combustion engines and electric motors. Previously limited in what they could lift with their primitive pulley systems, modern cranes use sophisticated hydraulic systems to provide a far superior lifting capacity.
Modern cranes are built to suit the specific requirements of a job. They come in many forms, including jib cranes, tower cranes, overhead cranes, mobile cranes, gantry cranes, telescopic cranes, floating cranes, aerial cranes and even self-erecting cranes.
The principle of mechanical advantage has allowed us to create huge edifices and lift staggeringly heavy weights, and it’s all thanks to the invention and refinement of cranes throughout history.

Previous post:

Next post: