46 - 05/98 - Overweight Containers - Worldwide
In many trades, containers are loaded onboard ship by shore gantries or shore cranes, with the intention that they be discharged using ship's cranes. We have seen many cases where damage has been caused to ship's cranes because the actual weight of a container being discharged exceeds the safe working load of the ship's crane, something which is only realised at the discharge port. There is a danger of serious injury to ship's crew and shore personnel in such a situation.
At the loadport, the ship's officers should ensure that containers being loaded are within the safe working load of the ship's crane which will be used for discharge, and are stowed in positions where they can be safely reached by those cranes. Officers should take into account the weight of any spreader or other lifting equipment which will increase the total weight to be lifted by the crane.
At the discharge port, ships officers should ensure that any safety devices or cut-outs on ship's cranes are functioning properly before commencing cargo operations. During cargo operations officers should bear in mind the fact that the declared weights of containers might be incorrect. Where a safety device comes into operation even though the declared weight of the container is within the crane's Safe Working Load, it should initially be assumed that the declared weight is not correct. The correspondent can be contacted for assistance or advice.
Officers should also be aware that some containers may be 'end-heavy', with most of the cargo weight loaded at the back of the container, away from the doors. End-heavy containers can be loaded normally by shore gantries which lift the container by its four corners, but can swing wildly and be difficult to control when lifted by a crane with a single hook and swivel.
Source of Information: Bill Kirrane - E5