Used Self Erect Cranes Nova Scotia - The tower crane's base is generally bolted to a huge concrete pad that provides really crucial support. The base is attached to a mast or a tower and stabilizes the crane that is affixed to the inside of the structure of the building. Often, this attachment point is to a concrete lift or to an elevator shaft.
The crane's mast is usually a triangulated lattice structure which measures 0.9m2 or 10 feet square. Attached to the very top of the mast is the slewing unit. The slewing unit consists of a gear and a motor that enable the crane to rotate.
Tower cranes are able to have a maximum unsupported height of 80m or two hundred sixty five feet. The maximum lifting capacity of a tower crane is sixteen thousand six hundred forty two kilograms or thirty nine thousand six hundred ninety lbs. with counter weights of twenty tons. Moreover, two limit switches are used in order to ensure the operator does not overload the crane. There is also another safety feature known as a load moment switch to ensure that the operator does not surpass the ton meter load rating. Last of all, the tower crane has a maximum reach of two hundred thirty feet or seventy meters.
Due to their extreme heights, there is a science involved to erecting a crane. The stationary structure will at first have to be transported to the construction site by utilizing a huge tractor-trailer rig setup. Then, a mobile crane is utilized so as to assemble the machine part of the crane and the jib. Then, these parts are connected to the mast. The mobile crane next adds counterweights. Crawler cranes and forklifts can be a few of the other industrial equipment that is utilized to erect a crane.
When the building is erected, mast extensions are added to the crane. This is how the crane's height is able to match the building's height. The crane crew uses what is referred to as a climbing frame or a top climber that fits between the top of the mast and the slewing unit. A weight is hung on the jib by the work crew so as to balance the counterweight. Once complete, the slewing unit could detach from the top of the mast. In the top climber, hydraulic rams are used to adjust the slewing unit up an extra 6.1m or 20 feet. After that, the driver of the crane utilizes the crane to insert and bolt into place one more mast section piece.
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