A tower crane is a huge lifting equipment used on skyscraper building sites. They can reach heights of more than 80 meters unsupported. Tower cranes have a lifting capacity of up to 20 tons, allowing them to move almost all building materials at the same time. They are erected next to the building to ensure stability.

Because it is a fixed piece of equipment, the crane’s base doesn’t move. A large, fixed tower supports a horizontal beam, or jib, which stands atop the tower to create an uneven letter “T.” A tower crane is often used in construction projects to install steel beams and other heavy building materials. It can also be used in the shipping and transportation industries to load and unload heavy cargo ships.

The tower crane’s base rests on a concrete pad, the thickness of which varies depending on the crane’s height and weight. Large anchor bolts are used to secure the tower’s base to the concrete, and they may penetrate several feet into the ground. This keeps the tower securely anchored, minimizing the chance of collapse.

The jib rests on top of the vertical tower, which stretches hundreds of feet into the air. The longer section of the jib has cables connected to it to move or position objects below, while the shorter piece extends away from the cables to serve as a counterweight. To improve the crane’s balance, more concrete or steel counterweights can be hung from the shorter part of the jib.

Where the jib meets the tower, it is normally where an operator car is positioned. The tower crane operator controls the jib and the movement of the materials while seated inside this car. The operation of connecting materials to the tower crane’s cables is overseen by someone on the ground or within the building. The person who does this is called a “rigger,” and he or she talks to the crane operator either by radio or by hand signals.