Device and method for dredging bed material under water

摘要

Abstract The invention relates to a device and method for dredging bed material under water. The device 5 comprises a vessel which can be anchored to an underwater bed and has a ladder which can be positioned downwards at an angle into the body of water from the vessel and which is provided with a cutting tool at its free end, the cutting tool comprising a number of excavating elements arranged around a common rotation axis. The cutting tool comprises a passage for dug-up bed material which adjoins an inlet end of a discharge means for the dug-up bed material, which 10 discharge means comprises a carrier for the bed material which is driven by means of a mechanical drive, which carrier comprises two conveyor belts which rotate in opposite directions of rotation across each other at the same time. The invention makes it possible to dig up underwater beds while preventing sediment spill. 132 ^ 108 --- 107 Fig. 3