Different container lifting methods and devices are used to handle the shipping containers in different sizes or types at port or intermodal terminals.
Dry freight or cargo containers are the most popular shipping containers that primarily used to store and transport products and cargos across different modes of transport from ship to rail to truck. Thousands of cargo containers need to be handled every day at ports, therefore, in order to increase throughput capacity, you must adopt the right container lifting method and device to handle the empty or loaded shipping containers.
Standard ISO shipping containers are 8ft (2.43m) wide, 8.5ft (2.59m) high and of either 20ft (6.06m) or 40ft (12.2m) standard lengths. Smaller 8ft and 10ft containers, longer 45ft, 48ft, 53ft container are also available. There are also special cargo containers like high cube containers, open top containers, flat rack containers and refrigerated containers to suit for various business need. There are four basic containers lifting methods: the top lift spreader method, the top lift sling method, the bottom lift sling method and the forklift method.
Empty containers can be lifted by all the above methods with proper equipment. Container lift spreaders are particularly designed to stack, load and unload the standard ISO containers, matching up with the sizes of 20ft, 40ft or 45ft containers. The container spreaders have lifting devices specially design to connect to the four top corner fittings of cargo container and then lift it with vertical force.
The top lift sling method is to use a hook instead of spreader to lift the containers. The container is lifted by all four top corner fittings with forces applied other than vertically. The bottom lift sling method can be used for empty and loaded containers lifting. The container is lifted from the side of the four bottom corner fittings attached by slings to a spreader beam hang above. If equipped with fork-lift pockets, the empty or load containers can be lifted by means of forks. The forks should ideally extend the whole width of the container when lifting it.