The Mechanical Single Rope Clamshell Grab, also called Touch-Down Grab, is especially designed for cranes with a single cable drum. Also most vessel cranes have single drum cranes, that cannot operate 2- or 4-Rope Grabs. In such case this grab will be a practical On-The-Hook solution. A mechanism on the grab, locks/unlocks the grab to open or close each time it touches the ground. This system is mostly prefered, if there is only one cable available.
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