Can any one give me details @ tower crane used for construction?
A tower crane is T shaped. The stem of the T is made in sections which are assembled on site. All it does is support. Some tower cranes have a lifting section that can raise everything above it, creating a gap into which a new section can be added, allowing making the crane much taller than any temporary crane. The cross bar carries the motor/generator unit, counterweights, and lifting mechanism and a housing for the operator all mounted on a pivot so the top turns 360 degrees. Some cranes have hinged top parts so they can reach out in one direction but fold up shorter to avoid nearby buildings. Tower cranes are usually mounted on a heavy concrete base that is left in place after the building is finished, under a plaza, floor, or driveway. Portable units exist which have a crawler type base. There is also a version that climbs up the structure of a building as it is built. In the T top, there are two sets of cables. One moves the carrier back and forth to position the hook closer and f
