CANTILEVER CRANE

Cantilever Crane

Cantilever Crane

1: Cantilever Crane, with a horizontal jib fixed to the top of a vertical tower.

The introduction of the winch and pulley hoist soon lead to a widespread replacement of ramps as the main means of vertical motion. 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. Also, the practice of erecting large monolithic columns was practically abandoned in favour of using several column drums.

2:the vertical tower is fixed at the base , the jib is fixed at the top of the tower

The maximum length of its jib which is fixed at the top of the tower can be 60m and also can be reassembled to 55m,50m,45m,40m, which can have a wide work range spite of barriers.The anchoring tower crane has the hoisting height of 46.2m.The tower crane use fluid drive system to increase or decrease mast height so as to make proper crane height for different building height.The climbing tower crane has the hoist height of 161m.At specific requirement and through special treatment ,the anchoring tower crane can have the hoisting height of 51.2m and the climbing one can have the hoisting of 200m.

3: For the model the load is assumed to be suspsended in position at the end of the jib at a distance of 400mm from the centre line of the tower.

The true self erect tower crane is smaller and of lower capacity than its assisted erect counterpart, but has the great advantage of being quick and easy to erect. The erection procedure is well within the capability of a trained fitter or competent driver and the newly erected crane does not have to undergo the sort of comprehensive commissioning procedures required by an assisted erect crane.

4: The model must carry a load of 2kg suspended from the end of the jib and a counter balance weight suspended at the opposite end of the jib at a distance of 200mm from the centre line of the tower, the jib must include a bar at each end from which the two weights can be hung

Erection of this type of crane is normally carried out by a crew and an engineer, trained in the specific erection procedures required. At the conclusion of the erection the crane will be subjected to a thorough examination and an application of a 25% overload followed by the setting of the safety devices.

Jibs of 50m and longer are available for applications where greater area coverage is required, and tower heights of up to 180m can be readily found for the project that needs this sort of lift height. A range of hoist and trolley winches are offered by the crane manufacturers, providing the crane user ...