When purchasing a used tower crane, it’s essential to conduct a thorough inspection and assessment to ensure safety, reliability, and cost-effectiveness. Here’s a detailed checklist to guide you through the process:
1. Documentation & Certification:
- Ownership Papers: Verify the original ownership documents and ensure there are no legal disputes.
- Service History: Check maintenance records and the crane’s service history.
- Inspection Certificates: Look for the latest third-party inspection certificate to confirm the crane’s working condition.
- Load Test Reports: Ensure valid load test certificates are available.
- CE Certification/IS Standards: Confirm compliance with the required standards in the operating region.
2. Age of the Crane:
- Determine the year of manufacturing and the number of years the crane has been in service.
- Compare the crane’s operational age with the lifespan recommended by the manufacturer.
3. Visual and Structural Inspection:
- Main Structural Elements: Inspect the tower, jib, and mast sections for cracks, corrosion, or bending.
- Welds: Check for broken or repaired welds on structural components.
- Paint Condition: Flaking or rust indicates prolonged exposure or lack of maintenance.
- Counterweights & Bolts: Examine counterweights and bolts for secure placement and condition.
4. Mechanical Components:
- Slewing Ring & Bearings: Ensure the slew ring and bearings rotate smoothly and are free of noise or play.
- Gearboxes & Motors: Listen for unusual noises or vibrations in gearboxes and motors.
- Winch Drum & Ropes: Inspect for wear, fraying, or elongation of wire ropes. Check if the winch drum grooves are intact.
- Hydraulic Systems: Check for leaks, pressure consistency, and smooth operation of hydraulic parts.
5. Electrical Systems:
- Control Panels: Inspect the condition of control panels, wiring, and electrical enclosures.
- Limit Switches: Test the limit switches for jib movement, hook lifting, and slewing.
- Circuit Boards: Ensure there is no visible damage or rust in circuit boards or control boxes.
6. Operational Testing:
- Conduct a trial run to check lifting, slewing, trolley movement, and hoisting speed.
- Test all the safety features like emergency stops, limit switches, and overload protection systems.
7. Compatibility & Configuration:
- Ensure the tower crane’s configuration (jib length, mast height) matches your project’s needs.
- Check if additional mast sections, jib extensions, or configurations are required and their availability.
8. Wear & Tear Analysis:
- Evaluate wear on pulleys, sheaves, and other moving parts.
- Inspect the crane for potential fatigue or excessive wear on frequently used components.
9. Spare Parts Availability:
- Confirm the availability of spare parts for the specific model.
- Consider sourcing from multiple vendors or getting an estimate on replacement part costs.
10. Safety Systems Check:
- Verify the condition of anti-collision systems, load moment indicators (LMI), and emergency cut-offs.
- Test the anemometer for wind speed monitoring and ensure proper calibration.
11. Brand Reputation & Market Value:
- Research the crane’s model for known issues or defects.
- Compare with similar cranes in the market to assess if the asking price is reasonable.
12. Transportation & Erection Costs:
- Calculate dismantling, transportation, and re-erection costs.
- Ensure the crane can be easily disassembled and transported to your site.
13. Seller Reputation:
- Verify the seller’s credibility and reputation in the industry.
- Request references or feedback from previous clients if possible.
Taking a systematic approach and possibly involving a third-party inspector can help you make a well-informed purchase, ensuring safety and long-term operational efficiency.