Crane Operation and Load Handling
What this domain tests
This domain tests whether you can apply the load chart during operation, control the load smoothly, and avoid side loading, shock loading, and instability. The exam focuses on radius, boom length, quadrants, deductions, travel restrictions, and power-line and wind limits.
Core rules and concepts
- Net capacity = gross chart capacity minus all deductions: hook block, slings, jib, auxiliary head, and other attached equipment.
- Radius is measured from the crane's centre of rotation to the load's centre of gravity, not to the boom tip. Boom length, angle, and radius must match the chart.
- Check the quadrant and configuration. A 360° rating may not apply; some charts are rated only over the front or rear.
- Avoid side loading, dragging, and shock loading. Booming down or swinging too fast can overload the boom or cause the load to drift.
- Travel with a load only when the chart specifically permits pick-and-carry operation and the route, tire pressure, and ground are suitable.
- Maintain power-line limits and stop when wind, visibility, or ground conditions exceed safe limits.
- Use tag lines where needed, but keep personnel clear of the load and swing path.
Worked example
At a 14 m radius and 30 m boom, the chart gives 12,000 kg gross. Deductions are 350 kg hook block, 150 kg slings, and 600 kg stowed jib: total 1,100 kg. Net capacity = 10,900 kg. The load weighs 10,000 kg, so the lift is within capacity. If the chart footnote says the jib deduction applies only when stowed, confirm the jib is actually stowed and secured before relying on that figure.
Traps that cost marks
- Reading capacity at boom length instead of radius.
- Forgetting hook block, rigging, and stowed attachment deductions.
- Using an on-tire chart for a pick-and-carry over the side.
- Assuming all quadrants have the same rating.
- Swinging or booming too fast and inducing load swing or side load.