Loosen and remove the high-tensile structural bolts connecting the slewing assembly to the top mast section.
: Use of radio services for coordination between operators, supervisors, and riggers. SafeWork NSW 2. Pre-Dismantling Preparation
Secure the mobile crane rigging to the cabin and slewing ring assembly. Note that this is typically one of the heaviest and most unbalanced lifts.
Tower crane dismantling is a high-risk engineering operation requiring precise planning, specialized equipment, and strict adherence to safety protocols. This method statement outlines the step-by-step procedures, technical requirements, and safety measures necessary to safely decommission and lower a top-slewing tower crane from a construction site.
Ensures all components are balanced and secured before disconnecting.
Ensure adequate artificial lighting if operations extend into dawn or dusk. 5.3 Safety Checks
If you would like to tailor this document further, please let me know: The specific of the tower crane. The capacity and type of assist crane you plan to use. Whether the crane is a luffing jib or a hammerhead type.
Verify that all technicians are wearing standard PPE: hard hats with chin straps, hi-vis vests, steel-toe boots, and full-body harnesses with double lanyards for fall arrest. 6. Step-by-Step Dismantling Sequence
Unbolt the cabin from its platform and lower it to the ground. Step 7: Slewing Unit and Ring Gear Removal
Attach the lifting tackle to the top mast section or climbing frame (if applicable).
The following emergency procedures will be in place during the dismantling work:
Rig the designated counterweight blocks using approved lifting lugs or slings attached to the assist crane. Take the tension on the assist crane hoist line.
| | XYZ High-Rise | |------------------|----------------| | Crane Model: | Potain MD 560 | | Dismantling Date: | 15 Nov 2025 | | Appointed Person: | J. Smith | | Mobile Crane: | Liebherr LTM 1160 (160t) | | Weather Limit: | Wind < 20 mph, no precip | | Sequence Step | Responsible | PPE | Permit Required | | 1. Site setup | Supervisor | HV, Gloves | Exclusion zone | | 2. Jib dismantle | Rigger A | Harness, radio | Lift plan | | 3. Counter-jib | Rigger B | Harness | Lift plan | | … | … | … | … | | Emergency contact: | Site security: 555-0199 ||
Attach the rigging lines of the assist crane to the designated lifting points of the counter-jib. Take up the load tension.
This article is a general guide. Always consult your crane manufacturer’s specific manual, local legal requirements (OSHA 1926.1400, BS 7121, etc.), and a qualified appointed person before any dismantling operation.
Ensure the mobile crane is inspected, has a valid Safe Working Load (SWL) certificate, and that all lifting tackles (slings, shackles) are in good condition.
Use tag lines to guide the counter-jib safely to the ground. Step 5.4: Tower Head and Slewing Assembly De-erection
