In major ports, just as at huge constructions sites, cranes have to lift massive amounts of weight on a daily basis. This might include everything reinforced concrete for a parking garage or a shipping container full of new stereos from Japan. When the loads are moved around, the procedure has to be precise for everyone’s safety and for the effectiveness of the job itself. That’s why there are devices like spreader beams, also known as yokes.
These yokes are bars of metal that have a series of cables or ropes extended from a horizontal shaft below the boom of a crane. The various ropes and cables balance the load of a heavy object, so it won’t swing, and so the contents shipping container won’t shift or get damaged as they are moved. Other key tools like good hooks and slings are necessary. Container spreader beams fit shipping containers that are 20 feet long or 40 feet long, the two standard lengths. There are various models, ranging from a working load limit, or WLL, of 5 tons, up to one that is suitable for lifting 42 tons. That’s a lot of stereos.
Because spreader beams deal with great deal of weight, safety is one of the prime concerns of the crane operator. For example, they need to make sure a shipping container is intact and its load is balanced, then ensure the doors are closed. They will also take care to use their slings and hooks appropriately. Being methodical with this equipment is the only way to operate.