Telescopic Cage：Tower crane "growth device"

What is a tower crane telescopic cage?

The telescopic cage is the core climbing mechanism of a tower crane. It's a movable steel frame structure installed at the top of the tower. Simply put, it's the tower crane's "growth device"—the tower crane can "grow" section by section like bamboo through this system.

What does a telescopic cage look like?

It's a large, three-dimensional frame structure welded from structural steel. Its inner dimensions are slightly larger than a standard section of the tower, resembling a large "sleeve" covering the outside of the tower. The main structure includes guiding devices, a hydraulic system, an access platform, and an operating platform.

What is the primary function of the telescopic cage?

To enable the tower crane to self-climb. It allows the already installed tower crane to increase its height on the construction site without the need for large lifting equipment.

What role does the telescopic cage play throughout the tower crane's lifecycle?

1. Installation Phase: Assists in the initial jacking after initial installation.

2. Usage Phase: Performs periodic jacking with additional sections as needed to increase building height.

3. Dismantling Phase: Reverses the process, gradually lowering the tower section by section.

Why can't it be installed to the final height in one go?

1. Stability Limitations: The independent height of the tower crane is limited (usually 40-70 meters). Exceeding this limit requires anchoring to the building.

2. Transportation Limitations: Standard sections are manufactured in segments for easy transport.

3. Economic Efficiency: Jacking on demand saves initial investment costs.

What are the specific functions of the telescopic cage?

1. Load-bearing Function: Bears the entire weight of the upper part of the tower crane (up to hundreds of tons) during jacking.

2. Climbing Function: Provides smooth climbing power through a hydraulic system.

3. Guiding Function: Ensures no tilting or twisting during climbing.

4. Working Platform Function: Provides a safe operating space for installing new standard sections.

What are the advantages of the telescopic cage compared to other lifting methods?

1. No large auxiliary equipment required

2. Strong construction adaptability

3. Relatively higher safety

4. Good economy, reducing installation costs

5. Better precision control

What are the special weather requirements for jacking operations?

1. Wind speed limit: Below level 4 (approximately 5.5 m/s), instantaneous wind speed not exceeding level 6

2. Visibility: Good, sufficient lighting required at night

3. Precipitation: Operations are strictly prohibited in rain, snow, or fog.