These professional machines are generally used for taking out sand and rubble from lake, pond, river and sea.  And also they are used for cleaning lake, and getting wet clay from dams.

These machines are manufactured in the light of superior German technology. The diving depth of the machines is ranging up to 100 meters according to the model type.

Bridge columns attached to the pontoon and the grab mounted below the crane are the main components of the system.

The working principle of the system;
The grab diving into water with open mouth reaches the bottom of water and closes by rope to get material. Then grab is pulled up with rope drum. Water filled in the grab is waited to flow through the slots and the grab releases the material in hopper. Coarse material is separated from hopper grid and the material passing through the grid is being pre-screened before being transferred to land by belt conveyors on pontoon.