Used Self Erect Cranes Huntington Beach - The tower crane's base is generally bolted to a huge concrete pad that provides very crucial support. The base is connected to a mast or a tower and stabilizes the crane that is attached to the inside of the building's structure. Often, this attachment point is to an elevator shaft or to a concrete lift.
The crane's mast is often a triangulated lattice structure that measures 10 feet square or 0.9m2. Connected to the very top of the mast is the slewing unit. The slewing unit consists of a gear and a motor which enable the crane to rotate.
Tower cranes may have a max unsupported height of 80m or two hundred sixty five feet, while the tower crane's maximum lifting capacity is 16,642 kilograms or thirty nine thousand six hundred ninety lbs. with counter weights of twenty tons. Moreover, two limit switches are used in order to make sure that the driver does not overload the crane. There is also one more safety feature referred to as a load moment switch to ensure that the operator does not exceed the ton meter load rating. Finally, the tower crane has a maximum reach of 70 meters or two hundred thirty feet.
There is definitely a science involved with erecting a tower crane, particularly due to their extreme heights. First, the stationary structure needs to be brought to the construction site by using a large tractor-trailer rig setup. Next, a mobile crane is used in order to assemble the machinery part of the crane and the jib. These parts are then attached to the mast. The mobile crane then adds counterweights. Forklifts and crawler cranes may be a few of the other industrial machinery that is typically utilized to erect a crane.
Mast extensions are added to the crane as the building is erected. This is how the height of the crane is able to match the building's height. The crane crew utilizes what is called a top climber or a climbing frame which fits between the slewing unit and the top of the mast. A weight is hung on the jib by the work crew in order to balance the counterweight. When complete, the slewing unit can detach from the top of the mast. In the top climber, hydraulic rams are used to adjust the slewing unit up an additional 6.1m or twenty feet. Next, the driver of the crane uses the crane to insert and bolt into position one more mast section piece.
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