Used Self Erect Cranes Oceanside - Usually the base that is bolted into a huge concrete pad provides the necessary support for a tower crane. The base is connected to a mast or a tower and stabilizes the crane that is affixed to the inside of the building's structure. Normally, this attachment point is to an elevator shaft or to a concrete lift.
The crane's mast is normally 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 motor and a gear that allows the crane to rotate.
Tower cranes may have a max unsupported height of 80m or 265 feet, while the minimum lifting capacity of a tower crane is 16,642 kilograms or 39,690 pounds with counter weights of twenty tons. Moreover, two limit switches are used to be able to ensure the driver does not overload the crane. There is even one more safety feature called a load moment switch to ensure that the operator does not exceed the ton meter load rating. Lastly, the tower crane has a maximum reach of two hundred thirty feet or seventy meters.
There is definitely a science involved with erecting a tower crane, particularly due to their extreme heights. First, the stationary structure has to be transported to the construction location by using a huge tractor-trailer rig setup. Next, a mobile crane is utilized so as to assemble the machinery part of the jib and the crane. These parts are then connected to the mast. Afterward, the mobile crane adds counterweights. Forklifts and crawler cranes can be some of the other industrial machines that is typically 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 utilizes what is referred to as a top climber or a climbing frame which 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. 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 twenty feet or 6.1m. Next, the crane driver uses the crane to insert and bolt into place one more mast part piece.
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