The Single Rope Grab, also called Touch-Down Grab, is especially designed for cranes (like ship board cranes) with a single cable drive. 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.

A step by step description of a touch-down mechanism:

1. Grab is lowered at open position.
2. After grab touches down on the material, the rope from the crane is released until lose. The mechanism is locked now.
3. The grab is pulled up and will close (buckets or tines), filling up with material.
4. The loaded grab is taken to destination.
5. At unloading destination (in this case, a hopper), the grab will be lowered to touch-down again until crane rope is loose again. The mechanism is unlocked now.
6. When lifted, the material will spill out as the grab opens.
7. The grab is empty.
8. The grab is taken to loading destination