A cutterhead for dredging water-bed material from a body of water. The cutterhead comprises a shroud presenting a front margin for receiving water-bed material into an interior space of the shroud. The shroud additionally includes a port from which water-bed material can be removed from the interior space of the shroud. The cutterhead additionally comprises a rotatable cutterbar at least partially received within the interior space of the shroud. The cutterhead further comprises a debris guard positioned between the cutterbar and the port. The debris guard is operable to filter the water-bed material removed from the shroud through the port. At least a portion of the debris guard that faces the cutterbar includes a concave shape.

A suctioning device for suctioning impurities from the bottom of large artificial water bodies is provided. The suctioning device includes a flexible sheet configured to provide a structural frame; a plurality of first brushes depending from the sheet; a plurality of middle brushes; a plurality of lateral brushes; a plurality of suction points; a plurality of wheels configured to provide secondary support when the brushes are worn out; a plurality of collectors configured to gather the suctioned water into external suction lines; a plurality of internal suction lines configured to conduit the suctioned bottom water flow from the plurality of suction points to the plurality of collecting means; and a coupling device connecting the internal suction lines and the collectors, wherein a rate of the bottom water flow entering the suctioning device is the same or higher than a rate of water flow suctioned by an external pumping system.

A suctioning device for suctioning impurities from the bottom of large artificial water bodies is provided. The suctioning device includes a flexible sheet configured to provide a structural frame; a plurality of first brushes depending from the sheet; a plurality of middle brushes; a plurality of lateral brushes; a plurality of suction points; a plurality of wheels configured to provide secondary support when the brushes are worn out; a plurality of collectors configured to gather the suctioned water into external suction lines; a plurality of internal suction lines configured to conduit the suctioned bottom water flow from the plurality of suction points to the plurality of collecting means; and a coupling device connecting the internal suction lines and the collectors, wherein a rate of the bottom water flow entering the suctioning device is the same or higher than a rate of water flow suctioned by an external pumping system.

A jetting system for an undersea trencher has jetting conduits extending onward of its trench-cutting jetting swords. Jetting conduit nozzles direct liquid radially from their jetting conduits into the trench after the trench is excavated by the jetting sword cutting nozzles. The jetting conduits direct sufficient liquid into the trench to maintain the mix of trenched soil and water in the trench along the length of the conduits at not more than a super-critical density, extending the distance in which the product being laid in the trench is able to descend in the trench and increasing the likelihood that the product will be buried at the intended trench depth.

A cutterhead for dredging water-bed material from a body of water. The cutterhead comprises a shroud presenting a front margin for receiving water-bed material into an interior space of the shroud. The shroud additionally includes a port from which water-bed material can be removed from the interior space of the shroud. The cutterhead additionally comprises a rotatable cutterbar at least partially received within the interior space of the shroud. The cutterhead further comprises a debris guard positioned between the cutterbar and the port. The debris guard is operable to filter the water-bed material removed from the shroud through the port. At least a portion of the debris guard that faces the cutterbar includes a concave shape.

A device for removing granular material by suction is presented, the device comprising a suction head. The suction head comprises a lower end, an outlet for removing granular material from the suction head, and side walls, extending from the lower end to the outlet. The suction head further comprises one or more nozzles, configured to emit a pressurized fluid for fluidizing granular material, and one or more side inlets for the inflow of fluidized granular material into the suction head. The side inlets are located in a side wall, and the side inlets combined extend over at least 2% of the circumference of the lower end. A method for removal of granular material by suction from a granular material mass is also presented. The nozzles on an outside and the nozzles on an inside of the suction head provide a helical flow in the same direction.

There is provided a material transfer system including a reciprocating conveyor which selectively moves in a first direction of movement and a second direction of movement opposite the first direction of movement. The conveyor is configured to promote movement of material in the first direction and inhibit movement of material in the second direction. There is further provided a material transfer system comprising a first reciprocating conveyor which selectively moves material towards a first location. The system includes a second reciprocating conveyor which overlaps with the first reciprocating conveyor. The second reciprocating conveyor selectively moves material from the first location towards a second location. There is also provided a material transfer system comprising a passageway having an upstream inlet and a downstream outlet. The passageway may be a conduit, a siphon or chute. The system includes a reciprocating conveyor conveying fluvial material towards the inlet of the passageway.

Subsea blower device comprising at least one nozzle, at least one propel arranged to provide the nozzle with water, further comprising a chassis with belts for movement of the device along the seafloor. The device typically has at least one arm pivotally attached to the chassis so that the position of the arm in relation to a horizontal plane is adjustable, while the nozzle is attached to the arm.

A jetting system for an undersea trencher has jetting conduits extending aftward of its trench-cutting jetting swords. Jetting conduit nozzles direct liquid radially from their jetting conduits into the trench after the trench is excavated by the jetting sword cutting nozzles. The jetting conduits direct sufficient liquid into the trench to maintain the mix of trenched soil and water in the trench along the length of the conduits at not more than a super-critical density.

There is provided a material transfer system comprising a first reciprocating conveyor which selectively moves material towards a first location, and a second reciprocating conveyor which overlaps with the first reciprocating conveyor, with the second reciprocating conveyor selectively moving material from the first location towards a second location. There is also provided a material transfer system according to another aspect comprising a conduit in fluid communication with an upstream portion of the body of water, and a reciprocating conveyor configured to convey upstream said material in the body of water towards the conduit. There is further provided a reciprocating conveyor configured to promote movement of the material in a first direction and inhibit movement of the material in a second direction, and a conveyor position adjustment assembly configured to selectively move a first end portion of the conveyor relative to a second end portion of the conveyor.