Several commercial and industrial buildings can reach heights of more than 60 stories. Apparently, while these buildings are being constructed, they require equally tall cranes to be able to move the materials to the higher floors. There are cranes which are operated from the rear of trucks or other types that have their own vehicle connected. Tower cranes are the biggest kinds offered on the market.
Tower cranes are stand-alone structures found as part of a major city's downtown skyline on high-rise building projects. When new construction like for example skyscrapers or apartment buildings and commercial facilities like for instance shopping center are being constructed, odds are a crane would be on site.
Types
There are two different types of cranes: boom crane or the jib crane. The jib is a metal frame which extends from the main section. On a flat tower crane, the jib remains horizontal as it lifts items. On a luffing type of tower crane, the jib can ratchet to downward or upward angles. The lifting capacity for both kinds can range from 30 pounds to 10,000 pounds
Body
The crane's body is composed of a mast. This is a vertical steel frame which is a combination of separate parts. In order to increase the overall height of the machine, parts are added. The mast extends upward to where the desired height is, to the control module, which is a small room that has glass windows on all four sides or to the tower as it is also called. The crane driver works from inside of the tower.
Lift
To raise materials, the crane utilizes a braided metal cord. The cord extends all the way to the end of the jib or boom from a motor located next to the control module. There is a pulley system located at the end of the jib, through which the cord is positioned and lowered down. The jib that holds the cord becomes balanced by a counter jib situated on the tower's opposite side. The counter jib holds weights. These weights help to prevent the crane from tipping over when raising heavy materials.