Passive marine equipment recovery device
View Patent ↗A system for retrieving a device from the bottom of a body of water includes a clamp configured to be slidably affixed to the device above the water bottom. The clamp has a selectively engageable lock to fix a position of the clamp on the device. A line ratchet is coupled to the clamp. A line is disposed through the line ratchet. A first flotation device is coupled to one end of the line. A second flotation device is coupled to the other end of the line. The system includes means for applying tension to the line disposed proximate the second flotation device. The line ratchet is arranged to enable movement of the line therethrough toward the means for applying tension, and is also arranged to substantially prevent motion therethrough in the opposite direction.
1. A system for retrieving a device from the bottom of a body of water, comprising:
a clamp configured to be slidably affixed to the device above the water bottom, the clamp having a selectively engageable lock to fix a position of the clamp on the device;
a line ratchet coupled to the clamp;
a line disposed through the line ratchet;
a first flotation device coupled to one end of the line;
a second flotation device coupled to the other end of the line;
means for applying tension to the line disposed proximate the second flotation device, wherein the line ratchet is arranged to enable movement of the line therethrough toward the means for applying tension, the line ratchet arranged to substantially prevent motion therethrough in the opposite direction.
2. The system of claim 1 wherein the cable clamp comprises a housing having an opening therein to enable insertion of the device into the housing.
3. The system of claim 1 wherein the selectively engageable lock comprises wedge segments inserted through an opening in a longitudinal end of the housing, and a cam configured to move the wedge segments longitudinally into the housing, the wedge segments having tapered exterior surfaces configured to laterally compress when the wedge segments are moved longitudinally into the housing.
4. The system of claim 3 wherein the cam is operated by a lever coupled to the line, such that when the means for applying tension is operated, the lock is engaged.
5. The system of claim 1 further comprising a storage element coupled to a third flotation device, the storage element configured to hold portions of the device retrieved from the water bottom.
6. The system of claim 5 wherein the storage element comprises a bag.
7. The system of claim 1 wherein the device comprises a seismic sensor cable.
8. A method for retrieving a device disposed on the bottom of a body of water, comprising:
slidably affixing a cable clamp to a part of the device disposed above the water bottom;
moving the cable clamp proximate the water bottom;
locking the clamp in place on the device;
applying lifting force to one end of a line, the line functionally coupled to the clamp through an element enabling movement of the line in only one direction;
applying lifting force to the other end of the line; and
retracting the line from one of the ends thereof, the retracting comprising moving the line through the element.
9. The method of claim 8 further comprising, upon movement of the cable clamp proximate the water surface, storing part of the device lifted from the water bottom.
10. The method of claim 9 further comprising:
repeating the moving the cable clamp;
repeating the locking the clamp;
repeating the applying lifting force to each end of the line; and
repeating the retracting the line.
11. The method of claim 8 wherein the lifting force comprises buoyant force.
12. The method of claim 8 wherein the locking comprises frictionally engaging the device.