2.4. Dismantling Procedure

Dismantling procedure of tower crane is made easier with a climbing cage. If there is no climbing cage, we need the support of another mobile crane for the entire process.

When considering the dismantling of a tower crane, two scenarios arise: one where a climbing cage is available and one where it is not. If there is a climbing cage, the process is streamlined, allowing the crane operator to manage the dismantling without needing additional cranes. However, if the climbing cage is absent, a mobile crane must assist throughout the entire dismantling process, making it more complicated and potentially slower.

Think of the climbing cage like a ladder that helps you reach the top of a tree more easily without needing an additional person to lift you. Without it, you need a friend's help to hold the ladder steady while you climb down, complicating the process.

First, you have to remove the trolley part. After removing the trolley, you remove the counterweights. You remove the counterweights then you remove the jib. So, then you remove the counter jibs. After that, you remove the operator cap and the tower top and the turntable.

The dismantling procedure follows a specific sequence to ensure safety and efficiency:

1. Removing the trolley: This is the first step as it is the topmost part.
2. Counterweights: Next, the counterweights, which balance the crane, are removed to reduce the load.
3. Jib and counter jibs: Following that, the jib (the horizontal arm) and the counter jibs are taken off.
4. Operator cap and tower top: Finally, the operator cap at the top and the turntable are removed. This systematic approach prevents accidents and maintains control over the crane's structure during dismantling.

Imagine disassembling a complex toy. You would start with the items that are easiest to remove (like the wheels) before removing more integral components (like the body) to avoid damaging any parts. In dismantling a crane, the order of removal ensures safety just like it does when taking apart a toy.

You need the support of another mobile crane for the entire procedure if you do not have the climbing cage.

In the absence of a climbing cage, a mobile crane is essential for dismantling tasks. It provides the necessary lift and stability to remove heavy components like the operator cap and turntable safely. The mobile crane's presence is crucial for supporting the tower as each piece is removed; without it, the crane could become unstable and pose a risk of tipping over during the dismantling process.

Consider a friend helping you take down a tent. Without their help to hold the structure while you remove the stakes, the tent might collapse unexpectedly, possibly injuring you or damaging the tent itself. Similarly, the mobile crane acts as an extra set of hands that ensures everything stays secure during the dismantling.

After all sections are removed, you can remove the sections one by one with the help of another mobile crane.

Once the primary components of the tower crane are disassembled and safely on the ground, the final steps involve systematically removing any remaining sections one by one. The mobile crane assists by lifting each section carefully to prevent accidents. This careful handling is crucial to ensure that no parts fall or become damaged, and that the area remains safe for workers.

This step is like taking a cake apart layer by layer, ensuring that each piece is removed gently so the cake doesn't collapse or smash. Just like how you’d use a spatula to carefully lift each segment of the cake, the mobile crane helps to lift each section of the tower crane delicately.

The maximum free standing tower crane height permissible is 60 to 120 meters. Beyond 120 meters, the tower crane should take the help from the structure.

It is important to remember that tower cranes have specific height limitations to ensure stability. The maximum height for a free-standing tower crane is typically between 60 to 120 meters. If a crane must be used beyond that height, it needs to be anchored to an existing structure to help manage the forces acting on it and provide additional support against tipping.

This is similar to stacking blocks; if you stack too high without support, the tower may topple over. But once you attach the tower to a wider, more stable surface (like a table), the blocks can stand much taller without falling.

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