How Tower Cranes Work

By: Marshall Brain  | 

Parts of a Tower Crane

All tower cranes consist of the same basic parts:

  • The base is bolted to a large concrete pad that supports the crane.
  • The base connects to the mast (or tower), which gives the tower crane its height.
  • Attached to the top of the mast is the slewing unit — the gear and motor — that allows the crane to rotate.

On top of the slewing unit are three parts:


  • The long horizontal jib (or working arm) is the portion of the crane that carries the load. A trolley runs along the jib to move the load in and out from the crane's center.
  • The shorter horizontal machinery arm contains the crane's motor that lifts the load, along with the control electronics that drive it and the cable drum. The machinery arm also holds the large concrete counter weights
  • The operator's cab is where the crane operator sits to control the crane's movements.

Now let's find out how much weight this equipment can handle.