The top slewing tower crane (also known as upper slewing tower crane) is the standard crane type on high-rise construction sites. Unlike the bottom slewing crane, the slewing mechanism is located at the tower top, which enables larger cantilever distances and higher load capacities. Typical cantilevers range from 30 to 80 meters with hook heights exceeding 100 meters.
The structure consists of an undercarriage (foundation or traveling gear), tower, slewing platform with counter jib and counterweights, and the main boom. There are luffing jibs (hoist moves horizontally on the boom) and luffing booms (the entire boom tilts up and down). Luffing jibs are more common in high-rise construction, while luffing booms are used in confined spaces.
Leading manufacturers such as Liebherr, Potain (Manitowoc), and Wolffkran offer top slewing tower cranes in numerous size classes. Modern models feature load moment limitation, wind cutout automation, remote diagnostics, and semi-autonomous crane control systems.