Method and device for subsea dredging
First Claim
1. Method for moving subsea rocks and sediments along a sea floor, comprising:
- arranging on a movable chassis tubing which has a substantially constant cross-section between a mouth end and an ejection end, and which is flexible over at least a portion thereof, an ejector nozzle external to the tubing and connected to the tubing between the mouth end and the ejection end, a water pump which is connected to the ejector nozzle opposite to the connection to the tubing, and a power cable to supply power to the chassis from the sea surface;
disposing the movable chassis with tubing, ejector nozzle pump and power cable on the sea floor;
producing a pressure gradient in the tubing by pumping water from the water pump through the ejector nozzle, creating thereby suction at the mouth end of the tubing; and
utilizing the suction to move rocks and sediment from a first point on the sea floor adjacent to the mouth end to a second point on the sea floor adjacent to the ejection end.
2 Assignments
0 Petitions
Accused Products
Abstract
Method and device for moving subsea rocks and sediments, particularly at significant depths, for example in connection with removal of protective rocks around subsea installations where maintenance is to be conducted. The device includes a rigid or at least partly flexible tubing thorough which masses may be transported with the aid of a pressure gradient produced by an ejector nozzle arranged externally in relation to the tubing, and fed with water from a water pump. The device further includes a chassis adapted to be transported along the sea bottom. The required power is supplied through a cable from the surface, while the tubing preferably is remotely controlled by a manipulator.
-
Citations
14 Claims
-
1. Method for moving subsea rocks and sediments along a sea floor, comprising:
-
arranging on a movable chassis tubing which has a substantially constant cross-section between a mouth end and an ejection end, and which is flexible over at least a portion thereof, an ejector nozzle external to the tubing and connected to the tubing between the mouth end and the ejection end, a water pump which is connected to the ejector nozzle opposite to the connection to the tubing, and a power cable to supply power to the chassis from the sea surface;
disposing the movable chassis with tubing, ejector nozzle pump and power cable on the sea floor;
producing a pressure gradient in the tubing by pumping water from the water pump through the ejector nozzle, creating thereby suction at the mouth end of the tubing; and
utilizing the suction to move rocks and sediment from a first point on the sea floor adjacent to the mouth end to a second point on the sea floor adjacent to the ejection end. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. Device for moving subsea rocks and sediments along a sea floor, comprising a chassis constructed and arranged for movement along the sea floor, having disposed thereon:
-
tubing which is flexible over tubing which has a substantially constant cross-section between a mouth end and an ejection end, and which is flexible over at least a portion thereof, an ejector nozzle external to the tubing and connected to the tubing between the mouth end and the ejector end, a water pump which is connected to the ejector nozzle opposite to the connection to the tubing, and a power cable to supply power to the chassis from the sea surface, whereby pumping water from the pump through the ejector nozzle creates suction at the mouth end of the tubing sufficient to pick up rocks and sediment from the sea floor adjacent the mouth end of the tubing, and deposit the rocks and sediment on the sea floor adjacent the ejection end of the tubing. - View Dependent Claims (8, 9, 10, 11, 12, 13, 14)
-
Specification