Crane – machine, generally equipped with a hoist, wire ropes or chains, and sheaves, that can be used both to lift and lower materials and to move them horizontally. It is mainly used for lifting heavy things and transporting them to other places.
It uses one or more simple machines to create mechanical advantage and thus move loads beyond the normal capability of a man. 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.
- mechanical advantage – the advantage you gain when you use a machine to help you increase the force you can transmit. It can be calculated by dividing the resistance force (the force applied by a machine) by the effort force (the force applied to the machine).
- lever. hoist sheave, mechanical advantage