Spreader
A Spreader is the specialised lifting attachment on a container crane, straddle carrier or reach stacker that grips and lifts a shipping container. It is a steel frame that lowers onto the container and engages the four corner castings with rotating twistlocks, locking on so the box can be hoisted, moved and set down precisely.
Spreaders are telescopic, extending or retracting to handle different container lengths — 20ft, 40ft and 45ft — and a twin-lift (or tandem) spreader can lift two 20ft or even two 40ft containers at once to boost crane productivity. Specialised spreaders exist for awkward cargo. The spreader is the business end of container handling equipment: its reliability and speed of locking on and releasing directly affect how quickly containers are moved. A simple-looking but essential device, the spreader is what makes the rapid, standardised lifting of containers possible across every piece of container-handling equipment.
The whole speed of containerisation rests on being able to grab and release a box in seconds — that is the spreader's job, locking onto standard corner castings with twistlocks. Twin-lift spreaders double crane output by taking two boxes at once. Small and unglamorous, it is the essential interface between every crane and the container.
How does a spreader grip a container?
It engages the container's four corner castings with rotating twistlocks, locking on to lift it.
What is a twin-lift spreader?
A spreader that lifts two containers at once (two 20ft or two 40ft), increasing crane productivity.