How a Tower Crane is dismantled?

Answer 1

Very tall tower cranes use the self-jacking section of the mast to remove one mast section at a time. Once the main boom is near ground, a conventional crane removes the main boom and counter weights in sequence. Small tower cranes are removed without using the self jacking section by a conventional crane. In rare cases, stiff leg derricks and evenhelicopters can be used.

I think to dismantle the tower crane should do these works as follows:
1, under normal conditions, will be lifting Gan parallel to the building facades, removal of tower structure using the standard bottle top section, so that gradually the small drop tower, down procedures top-up procedures for the opposite. Until the tower fell to the initial installation height,then with crane tower crane to install according to the order of removal of the opposite.
2, in the unusual circumstances, such as the tower fell to the initial installation of a high degree of obstructions can not let the boom down when the order of installation, can be used cranes, lifting arm in the air will be divided into 2 ~ 3 removed but there must be a reliable security measures.
3, shaft independent drop tower method. France to adapt to the independent drop tower tower crane installed in the concave on the inside corner of the construction location, due to boom can not continue to decline in the tower on the roof, when lifting arm can be fitted with hinged Department - Auxiliary lifting equipment This would allow the tower continues to fall as well as removal of attached devices so on. Tower in the process of falling down all the parts removed from the auxiliary lifting equipment transported to the ground, until reduced to the initial installation height, in accordance with crane installed in reverse order followed by demolition.
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Answer 2

Dismantling a tower crane is a complex and carefully orchestrated process that requires skilled personnel and adherence to safety protocols. Tower cranes are commonly used in construction projects to lift heavy materials and equipment to great heights. Here's an overview of the steps involved in dismantling a tower crane:

1. **Planning and Preparation**:

   • Before dismantling begins, a detailed plan is developed. This plan considers factors such as crane type, height, load capacity, site conditions, and weather.

   • The crane operator and a team of skilled workers, including riggers and technicians, are involved in the dismantling process.

2. **Removing Loads**:

   • The crane's hook or hoist is used to lower any remaining loads or equipment from the crane's hook block.

3. **Dismantling the Boom**:

   • The boom (the horizontal arm of the crane) is disassembled section by section. This is done by attaching a tagline to each section and guiding it down as it's detached.

   • A smaller auxiliary crane, such as a mobile crane, might be used to assist in removing boom sections safely.

4. **Removing the Counterweights**:

   • The counterweights, which provide stability to the crane, are removed one by one using the crane's hoist or an auxiliary crane.

5. **Dismantling the Mast Sections**:

   • The mast sections, which are the vertical components of the crane, are disassembled from the top down. This is typically done by removing bolts and pins that connect each section.

   • A climbing frame might be used to facilitate safe access for workers as they dismantle the mast sections.

6. **Lowering the Slewing Unit**:

   • The slewing unit, which allows the crane to rotate, is carefully disconnected and lowered to the ground using a separate lifting device.

7. **Dismantling the Jib**:

   • If the crane has a jib (an additional arm that extends from the boom), it's disassembled using a similar process to that of the boom.

8. **Dismantling the Base and Supporting Structure**:

   • Once the upper components are removed, the crane's base and supporting structure are dismantled.

   • Mobile cranes or other lifting equipment might be used to help with the removal of larger sections.

9. **Transport and Storage**:

   • The dismantled components are carefully loaded onto trucks for transport to a storage facility or the next construction site where the crane will be needed.

10. **Site Cleanup and Restoration**:

    • After the crane and its components are removed, the site is cleaned up, and any traces of the crane's presence are restored.

Throughout the dismantling process, safety is of paramount importance. Procedures are followed to ensure the stability of the crane during disassembly, prevent accidents, and protect both the workers and the surrounding environment. Additionally, local regulations and industry standards play a crucial role in guiding the dismantling process.

It's important to note that the specific steps and equipment used for dismantling a tower crane can vary based on the crane's model, design, and the conditions of the construction site. Therefore, only trained and experienced personnel should perform crane dismantling operations.