Used Self Erect Cranes Santa Maria - Typically the base that is bolted into a big concrete pad provides the crucial support for a tower crane. The base is attached to a mast or a tower and stabilizes the crane which is connected to the inside of the structure of the building. Normally, this attachment point is to a concrete lift or to an elevator shaft.
Typically, the mast is a triangulated lattice structure measuring 0.9m2 or 10 feet square. The slewing unit is connected to the very top of the mast. The slewing unit consists of a motor and a gear which allows 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 sixteen thousand six hundred forty two kilograms or 39,690 lbs. with counter weights of 20 tons. Additionally, two limit switches are utilized in order to make certain that the driver does not overload the crane. There is even one more safety feature called a load moment switch to make sure that the operator does not surpass the ton meter load rating. Lastly, the tower crane has a maximum reach of 230 feet or seventy meters.
There is definitely a science involved with erecting a tower crane, especially because of their extreme heights. At first, the stationary structure has to be transported to the construction location by using a huge tractor-trailer rig setup. Then, a mobile crane is utilized so as to assemble the machinery part of the crane and the jib. These parts are then connected to the mast. The mobile crane next adds counterweights. Forklifts and crawler cranes can be some of the other industrial equipment which is utilized to erect a crane.
As the building is erected, mast extensions are added to the crane. This is how the crane's height could 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. Once complete, the slewing unit can detach from the top of the mast. In the top climber, hydraulic rams are utilized to adjust the slewing unit up an additional twenty feet or 6.1m. Next, the crane operator uses the crane to insert and bolt into place another mast section piece.
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