The International Cargo Handling Coordination Association (ICHCA) has provided an overview of some of the safety principles associated with safe lifting of ISO containers and tanks using hooks and wires.
According to ICHCA, any lifting operation of this type should be undertaken by competent persons in compliance with applicable regulatory frameworks and is the responsibility of the duty holder.
The use of gantry cranes and spreaders is the optimal and preferred method for lifting ISO containers and tanks (collectively referred to as Cargo Transport Units, CTUs) in most situations.
However, not all terminals have this equipment available. At some terminals it is therefore accepted practice to lift ISO containers and tanks using wires or chains and single-rope cranes, such as mobile harbour cranes (MHCs)1 or barge-mounted derricks.
Safety should always be considered in any lifting operation and this alert sets out some key principles when lifting any cargo including containers by hook and chain or wires.
Principles
- When handling ISO containers only methods allowed in ISO 3874 should be used. In general, lifting a packed ISO container by the top corner fittings requires a spreader or vertical slings or chains. Angled slings should not be used.
- In the case of a single-point lift, special attention should be paid to the risk of the container tilting owing to asymmetry of the centre of gravity.
- The load should be as secure in the air as it is on the ground.
- The slinging method should be suitable for the load to be lifted, with adequate means of attachment to both the load and the lifting appliance.
- The mass of the load must not exceed the safe working load (SWL) of the slinging gear or lifting appliance.
- The load must not damage or be damaged by the slinging gear.
- Lifting operations should be planned by a competent person.
- Never work under a suspended load.
Lifting freight containers
The preferred method for lifting a packed freight container is to use a spreader which connects directly into the top corner fittings of all ISO containers and often regional or national designs. Where a MHC is to be used then the spreader can be attached directly to the load block.
Sometimes it is impossible to attach the spreader directly to the top of the container in which case, consider using vertical chains attached by hooks into the top and end apertures or corner fitting lugs.
For a flatrack lift wires should be vertical and attached to the top corner fittings. The centre of gravity should be below the top corner fitting. For example, a very small 5o degree vertical incline of the wire and 2g acceleration with a gross mass of 30 tonnes can break the posts in racking.
If the MHC is not able to use a spreader, then a spreader frame can be attached to the top of the container using lift-locks and the frame lifted using a lifting set.
Finally, the container can be lifted using slings attached to bottom corner fitting using lifting lugs and a transverse cross beam.
If a lift does not go to plan
If a lift does not go as planned (e.g. cargo shifts during the lift potentially shock loading slings) and there is risk of resulting damage, such as birdcaging, to lifting appliances/accessories there should be a new inspection.
This should include all potentially affected lifting appliances and/or accessories. There should also be a reviewed lifting plan which controls/addresses any previous plan failure.
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