Not everyone is fascinated about witnessing a tower construction site, neither the equipment rented to build the structure but what always catches the eye is a tall Tower Crane that is installed on the construction site. Not all construction companies have their own cranes and are usually rented from equipment rental companies. Check out stock on www.machineryplanet.ae Ever wondered how these structures grow?
To start with the crane installation a firm foundation is built. A Tower Crane mast section is set into this foundation using steel pedestals. Concrete is poured around the mast and the Crane is ready to be erected after curing of the concrete. Installation of the crane requires skilled technicians and a mobile crane unit which ideally has a capacity to rise to 100ft. A crane is never fully built but grows with a help of a crane climber one mast section at a time.
As the foundation and the Crane mast is setup, it is now time to install the tower sections. The tower sections connect to form a tall structure. Along with the tower sections a crane climber is installed which helps the crane grow throughout its use. A crane cabin is installed which is the location from where the crane is operated. The installation is in a manner that helps the cabin move along with the crane jib.
A counter jib is first installed that will hold the counterweights to balance the crane jib. Balancing the weight involves scientific calculations as too much can pull the crane to the direction of the counter jib and too little to the side of the jib. The purpose of the counter jib is to balance the load as well the weight of the crane. To install additional tower sections to the crane, the large hydraulic arms of the crane climber pushes the unit up by 20 feet and the crane operator uses the crane to lift another 20-foot mast section into the gap opened by the crane climber.
To make the crane operational, the ropes must be installed on the crane. The hook is moved along the working jib with a Trolley. Ropes are attached to the trolley. This work can take a few hours depending on the size of the crane and its design. The load line that hoists the rope is installed after the trolley lines. It runs from the back of the crane, through the tower top and out under the jib to the outer tip of the crane and is pinned in place.
The final process to make the crane operational is to set the motion limits for the hoist and trolley, followed by performing a load test to 100% of the cranes capacity.
The maximum load that a Tower crane can lift is 18 metric tons, but this weight cannot be lifted at the end of the jib. The closer the load is to the mast more is the weight that the crane can hold. Ideally setting up of a Tower crane would require 12 – 15 Trailers, few mobile crane units, competent crew with skilled crane professionals and would cost an approx.. total of AED 75,000/- for the installation. Each of the tower sections are rented or bought separately depending on the height of the Crane and requirement.
Once the building is finished and it is time for the crane to come down, the process is reversed. The crane disassembles its own mast and then smaller cranes disassemble the rest.