A Tower Crane Dismantling Method Statement is a critical safety document that details the sequence, equipment, and precautions required to safely take down a crane. It typically follows a reverse order of erection, starting from the hook and moving down to the foundation. 1. Preliminary Preparations
Before any physical work begins, specific site conditions and administrative checks must be met:
Site Survey & Risk Assessment: A full site survey is conducted to identify hazards like adjacent buildings, power lines, or street furniture.
Weather Monitoring: Dismantling must stop if wind speeds exceed specific limits (typically 25 km/h or 14 m/s).
Exclusion Zone: A safe zone must be barricaded, with warning signs and guards to prevent unauthorized entry.
Permit to Work (PTW): Ensure all necessary permits and third-party certifications for equipment and personnel are in place. 2. Equipment & Personnel
Personnel: Only qualified professionals (erectors, riggers, and signalmen) who are medically fit should be involved.
Mobile Crane: A larger mobile crane (e.g., 150T or 160T) is often used to lower heavy sections like the jib and counter jib. tower crane dismantling method statement
Communication: Continuous radio or hand signal communication must be maintained between the operator, ground crew, and safety officer. 3. Standard Dismantling Sequence While specifics vary by crane model (like the Potain MCi 85 or Zoomlion 6517 ), the general top-down steps are:
Hook & Hoist: Remove the hook block and reeve the hoist rope back onto the drum.
Counterweights: Use a mobile crane to remove the rear counter ballast blocks one by one to maintain balance.
Front Boom (Jib): Sling and dismantle the jib in sections, often using the mobile crane to lower them to the ground.
Operator's Cabin & Slewing Unit: Dismantle the cab, turntable, and slewing mechanism.
Mast Sections: Remove tower/mast sections one by one. If using a climbing frame (telescoping cage), it is used to lower the top sections within reach of a mobile crane.
Chassis & Foundation: Finally, dismantle the base frame, outriggers, or bogies and clear all debris from the site. 4. Safety Checks During Work A Tower Crane Dismantling Method Statement is a
Balance: Always ensure the crane is in balance before unpinning major components. Use trolleying to fine-tune balance if needed.
Stored Energy: Safely release any stored energy (e.g., hydraulic pressure or tensioned cables) before disassembly.
Lifting Accessories: Inspect all slings, chains, and shackles—the 3-3-3 rule suggests taking 3 seconds to inspect before every lift. Tower Crane Dismantling Procedure | PDF - Scribd
A Tower Crane Dismantling Method Statement is a critical safety document that outlines the step-by-step process, equipment requirements, and risk mitigation strategies for removing a crane from a construction site 1. Preliminary Preparations
Before the physical dismantling begins, several administrative and site-related tasks must be completed: Permits & Documentation: Ensure all necessary permits, such as a Permit to Work (PTW)
and valid third-party inspection certificates for all lifting gear, are in place. Site Inspection:
Verify that the ground for the auxiliary mobile crane is stable and level. Use steel plates or timber sleepers to distribute weight. Exclusion Zones: Part 6: Environmental & Weather Protocols | Condition
Barricade the area below the hoisting spot and demarcate the work zone to prevent unauthorized access. Weather Monitoring:
Appoint a person to monitor wind speeds; all operations must typically cease if wind speeds reach 2. Sequence of Operations (Top-Down)
Dismantling is generally the reverse of the installation process, focusing on maintaining the crane's balance at every stage. Tower Crane Dismantling Procedure | PDF - Scribd
You should adapt the site-specific details (crane model, load capacities, access constraints, weather limits, etc.) before use.
| Condition | Action | |-----------|--------| | Wind speed > 20 mph (9 m/s) | Stop all lifts above 50ft height. | | Wind speed > 25 mph (11 m/s) | Complete stop – secure partial load. | | Rain / fog (visibility < 50m) | Stop work. | | Lightning within 10 miles | Stop work, evacuate crane area. | | Night work | Only permitted with full lighting (500 lux minimum). |
Before dismantling begins, verify all equipment is certified and inspected.