how to prepare lifting plan and load calculation

Lifting Plan and Load Calculation  

When planning a lift, safety and precision are key. Here’s a straightforward breakdown of how to approach it:

1. Understand the Load 

Weight: Confirm the exact weight of the object (check manufacturer specs, weigh it, or calculate based on material density).

Dimensions: Note the size, shape, and center of gravity—bulky or uneven loads require special rigging.

- **Attachment Points**: Identify secure lifting points to avoid imbalance or damage.  

2. Choose the Right Equipment

Crane/Lifting Device: Ensure its capacity exceeds the load weight (factor in a safety margin, usually 25-30% above the load).

Slings/Chains/Rigging: Check their Working Load Limit (WLL) and ensure they’re rated for the load.

Hardware: Shackles, hooks, and spreader bars must also meet weight requirements.

3. Calculate Total Load

Include:

Primary Load: Weight of the object.

Rigging Weight: Slings, hooks, and attachments add extra load.

Dynamic Factors: Wind, movement, or acceleration can increase force (use multipliers like 1.5–2x for safety).

Example Calculation:

- Object weight: 10,000 kg  

- Rigging weight: 500 kg 

- Dynamic factor (1.5x): (10,000 + 500) × 1.5 = 15,750 kg total load 

- Crane capacity needed: 20-ton crane (to stay within safe limits).

4. Verify Ground Conditions

- Ensure the ground can support the crane/equipment (check for stability, mats, or outriggers if needed).  

5. Plan the Lift

- Path: Clear obstacles and ensure no power lines/structures interfere.  

- Communication: Use spotters and hand signals/radios.  

- Contingencies: Have a plan for emergencies (e.g., load stuck, sudden weather changes).  

6. Document & Brief the Team

- Write a formal lifting plan (including weights, equipment, roles, and risks).

- Conduct a toolbox talk to review steps with all workers.

Final Tip: When in doubt, overestimate loads and underspeed lifts—better safe than sorry.