CUTTING TOOL

Abstract

An underwater tool including a grabber arrangement and a cutter arrangement connected together. The grabber arrangement comprises a plurality of grabber elements disposed on first and second sides of the tool. The cutter arrangement includes a cutter slot, an anvil movable to close the slot comprises an anvil and a cutter blade. In use, a cable is held by the grabber arrangement, and thereby moved into the slot which is then closed by the anvil so as to entrap the cable within the slot. The cutter blade is then driven against the anvil so as to cut the cable.

Claims

1. An underwater tool comprising a grabber arrangement and a cutter arrangement, wherein the grabber arrangement comprises: a plurality of grabber elements; and the grabber elements comprise one or more first grabber elements and one or more second grabber elements.

2. A tool according to claim 1, wherein the grabber arrangement and the cutter arrangement are connected together or arranged in a set/preset disposition relative to one another, such as a longitudinally set and transversely movable disposition relative to one another.

3. A tool according to claim 1, wherein the grabber arrangement and the cutter arrangement are directly or indirectly connected together, such as rigidly connected together, such as by one or more rigid members and/or a frame.

4. A tool according to claim 1, wherein: the first grabber element(s) is/are disposed on a first side of the tool, and/or the second grabber element(s) is/are disposed on a second side of the tool, and/or the first/second grabber elements are pivotably attached to a (main) body of the tool, and/or the first/second grabber elements comprise arms or fingers, and/or the/each grabber element is claw, talon or tine shaped; and/or the first/second grabber elements are curved or arcuate in shape, and optionally in such case a concave surface of each grabber element faces or is faceable towards a centre line of the tool, and/or a convex surface of each grabber element faces or is faceable away from a/the centre line of the tool.

5. A tool according to claim 1, wherein when in an open disposition the/each first/second grabber element is/are disposed on a/the respective first/second side of the tool.

6. A tool according to claim 1, wherein when in a closed disposition a distal end of each first/second grabber element is/are disposed on a/the respective second/first side of the tool.

7. A tool according to claim 1, wherein: in an open disposition the grabber elements provide an open jaw for receiving a cable or conduit, and in a closed disposition the grabber elements provide a closed jaw having an internal/closed space or throughhole, such as for grabbing and/or holding and/or retaining a cable or conduit.

8. A tool according to claim 1, wherein the tool comprises: a longitudinally extending line, such as a centre line, the line being coincident with a position where a cable or conduit is grabbed (and/or retained) by the tool, in use, and optionally a/the throughhole or internal space is centred on the line, and optionally further the grabber arrangement and the cutter arrangement are spaced one from the other along said line, or the grabber arrangement and the cutter arrangement are provided proximal or adjacent one another on said line.

9. A tool according to claim 8, wherein the cutter arrangement comprises a cutter body, and optionally the cutter body is slidably attached to a main body of the tool, and/or the cutter body moves or slides perpendicularly to said line, such as along a second line which second line intersects said line.

10. A tool according to claim 9, wherein the cutter arrangement/cutter body comprises a cutter slot, and optionally: the cutter slot is disposed transverse to the line, and/or the grabber elements are disposed (so as to move) transverse to the line, and/or. the slot is adapted for receiving a cable or conduit, and/or the cutter body is movable along said second line such that the slot coincides with the line.

11. A tool according to claim 1, wherein the cutter arrangement comprises an anvil, and optionally: the anvil is movable or drivable from a first position to a second position, such as by an anvil driving arrangement, and/or the anvil is movable, such as slideably movable transversely to an/the longitudinally extending line of the tool, and/or the anvil is movable, so as to close or open a jaw or mouth of a/the slot of the cutter arrangement.

12. A tool according to claim 1, wherein the cutter arrangement comprises a cutter blade, and optionally: the cutter blade is provided slideably within a/the cutter body, and/or there is provided a cutter blade driving arrangement, such as for moving the cutter blade from a first position to a second position, and optionally further: in said first position of the cutter blade, the cutter blade is distal a/the throughhole/closed space of a/the slot, and/or in said second position of the cutter blade, the cutter blade is within a/the throughhole/closed space of a/the slot, and/or in said second position of the cutter blade, a cutting or distal edge of the cutter blade abuts/strikes/contacts an/the anvil.

13. A tool according to claim 12, wherein prior to cutting a cable, the cable is provided within a cutter slot and between the cutter blade and an anvil.

14. A tool according to claim 9, wherein the cutter body is resiliently biased or biassable, such as, hydraulically/sprung biased or biassable, or floats relative to a main body.

15. A tool according to either claim 11, wherein the throughhole is distal or spaced from said anvil second position, such as when viewed along a direction of the centre line, and optionally such arrangement provides that the anvil is deployed, that is moved from said anvil first position to said anvil second position, without touching a cable retained in the throughhole.

16. A tool according to claim 10, wherein: there is provided an arrangement or means for guiding a cable or conduit into the slot as the grabber arrangement or grabber elements close around the cable or conduit, for example, as the grabber elements move from a/the first (open) position to a/the second (closed) position, and/or there is provided a guide arrangement which optionally comprise guide plates provided on each side of the slot.

17. A tool according to claim 1, wherein the grabber arrangement or means and/or the cutter arrangement or means are adapted to respectively grab and cut a cable, or a conduit or pipe, such as an underwater cable or underwater conduit or pipe.

18. A tool according to claim 1, wherein the grabber arrangement is adapted to retain an end of the cable, conduit or pipe after cutting of the cable, conduit or pipe.

19. A tool according to claim 1, wherein the tool comprises a gripper arrangement.

20. An underwater cable or conduit grabbing and cutting apparatus, comprising at least one tool, such as grabber and cutter tool, according to claim 1.

21. The apparatus according to claim 20, wherein the apparatus comprises one or more line and/or wires, the one or more lines and/or wires optionally comprising a lifting wire and/or an orientation line, in use, the lines and/or wires optionally extending from a vessel to the at least one tool.

22. A method of grabbing and/or cutting an underwater cable or conduit comprising the steps of: providing at least one tool according to claim 1; positioning said tool adjacent a cable or conduit.

23. A method according to claim 22, wherein the method comprises grabbing the cable or conduit with the grabber arrangement.

24. A method according to either of claim 22, wherein the method comprises (subsequently) cutting the cable with the cutter arrangement.

25. An underwater tool comprising a grabber arrangement or means and/or a cutter arrangement or means.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Embodiments of the present invention will now be described, by way of example only, and with reference to the accompanying drawings, which are:

[0057] FIG. 1 is a sectional side view of a grabbing and cutting tool according to an embodiment of the present invention positioned over a cable;

[0058] FIG. 2 is a perspective view of the grabbing and cutting tool of FIG. 1;

[0059] FIG. 3 is an end view of the grabbing and cutting tool of FIG. 1 with grabbing elements in an open disposition;

[0060] FIG. 4 is a side view of the grabbing and cutting tool of FIG. 1;

[0061] FIG. 5 is a further end view of the grabbing and cutting tool of FIG. 1 with grabbling elements in a closed disposition;

[0062] FIG. 6 is an end view of the grabbing and cutting tool of FIG. 1 with the grabbing elements in a closed disposition and an anvil not deployed;

[0063] FIG. 7 is an end view of the grabbing and cutting tool of FIG. 1 with the grabbing elements in a closed disposition and the anvil deployed;

[0064] FIG. 8 is an end view of the grabbing and cutting tool of FIG. 1 with the grabbing elements in a closed disposition, the anvil deployed and a cutter blade ready for deployment;

[0065] FIG. 9 is an end view of the grabbing and cutting tool of FIG. 1 with the grabbing elements in a closed disposition, the anvil deployed and the cutter blade deployed;

[0066] FIGS. 10(A) to (E) are a sequence of perspective views of the grabbing and cutting tool of FIG. 1 showing the grabbing and cutting tool being positioned relative to a cable, grabbing the cable and cutting the cable;

[0067] FIGS. 11 is a partial sectional side view of a grabber and cutter tool according to a second embodiment of the present invention;

[0068] FIGS. 12(A) to (D) are a sequence of partial sectional side views of a grabber and cutter tool according to a third embodiment of the present invention, showing how the tool grabs and holds a cable, in use;

[0069] FIGS. 13(A) to (C) are a perspective view from one side and one end, an end view and a top view of a cutter arrangement capable of use in any of the foregoing first to third embodiments of the present invention; and

[0070] FIGS. 14(A) and (B) are a perspective view from one side, one end and below of a grabber and cutter tool according to a modified embodiment of the present invention.

DETAILED DESCRIPTION OF THE ENABLING EMBODIMENTS

[0071] Referring initially to FIGS. 1 to 9, there is illustrated an embodiment of a grabbing and cutting tool or grabber and cutter tool, generally designated 5, according to an embodiment of the present invention. The tool 5 can be described or referred to as a cutting cable grab.

[0072] In this embodiment, the tool 5 comprises an underwater tool. The tool 5 is adapted to grab and to cut a cable 10 or a conduit, pipe or the like. The tool 5 comprises a (cable/conduit/pipe) grabber arrangement or means 15 and a (cable/conduit/pipe) cutter arrangement or means 20. The grabber arrangement 15 and the cutter arrangement 20 are connected rigidly, i.e. connected together, by one or more rigid members or a frame, generally designated 25.

[0073] The grabber arrangement 15 comprises a plurality of grabber elements 30. The grabber elements 30 comprise one or more first grabber elements 30a and one or more second grabber elements 30b.

[0074] The first grabber element(s) 30a are disposed on a first side 35a of the tool 5. The second grabber element(s) 30b are disposed on a second side 35b of the tool 5. The first/second grabber elements 30a, 30b are pivotably attached to a (main) body, generally designated 40, of the tool 5. The first/second grabber elements 30a, 30b can be conveniently be referred to as arms or fingers. The first/second grabber elements 30a, 30b are typically curved or arcuate in shape. A concave surface 45 of each grabber element 30 faces towards a centre line C of the tool 5. A convex surface 46 of each grabber element 30 faces away from the centre line C of the tool 5. The/each grabber element 30 is in the form of a claw, talon or tine.

[0075] When in an open disposition of the grabber arrangement 15, the/each first/second grabber element 30a, 30b is disposed on the respective first/second side 35a, 35b of the tool 5. When in a closed disposition of the grabber arrangement 20, a distal end 50 of each first/second grabber element 35a, 35b is disposed on the respective second/first side of the tool 5.

[0076] By this arrangement, in said open disposition, the grabber elements 30a, 30b provide an open jaw 55 for receiving a cable 10. By this arrangement, in said closed disposition, the grabber elements 30a, 30b provide a closed jaw 55 having an internal space or throughhole 65 (i.e. transverse closed space or longitudinal throughhole) for grabbing and/or holding and/or retaining the cable 10.

[0077] It will be appreciated from the above that, in use, the grabber elements 30a, 30b move in overlapping co-action so as to effectively provide a scissor type action.

[0078] The tool 5 comprises longitudinally extending line C. The line C is coincident with a position where a cable 10 is grabbed (and retained) by the tool 5, in use. The throughhole 65 is substantially centred on the line C.

[0079] The grabber arrangement 15 and the cutter arrangement 20 are spaced one from the other along said line C. As can be seen from FIG. 1, the grabber arrangement 15 and the cutter arrangement 20 are provided proximal or adjacent one another on said line C.

[0080] The cutter arrangement 20 comprises a cutter body 70. The cutter body 70 is movable or slidably attached to a/the main body 40 of the tool 5. The cutter body 70 is slidable perpendicularly to said line C along a second line C2, which second line C2 intersects said line C. The cutter body 70 comprises a cutter slot 75. The cutter slot 75 is disposed transverse to the line C. The grabber elements 30 are disposed (so as to move) transverse to the line C. The slot 75 is adapted for receiving the cable 10. The cutter body 70 is movable along said second line C2 such that the slot 75 coincides with the line C. In this way the cable 10 can be received within the slot 75.

[0081] The cutter arrangement 20 comprises an anvil 80. The anvil 80 is movable or drivable from a first position (see FIG. 10C) to a second position (see FIG. 10D), e.g. by an anvil driving arrangement. By this arrangement the anvil 80 is moved from the first position, where a jaw 85 of the slot 75 is open to the second position where the jaw 85 or mouth of the slot 75 is closed. In said second position the cable 10 can be retained/trapped within the slot 75. The anvil 80 is movable, i.e. slidably movable, transversely and perpendicular to the line C and perpendicular to the second line C2. The anvil 80 is movable so as to selectively close or open the jaw 85 of the slot 75.

[0082] The cutter arrangement 20 comprises a cutter blade 90. The cutter blade 90 is provided slidably within the cutter body 70. There is provided a cutter blade driving arrangement, e.g. for moving the cutter blade 90 from a first position to a second position. In said first position of the cutter blade 90, the cutter blade 90 is distal the throughhole 65 of the slot 75. In said second positon of the cutter blade 90, the cutter blade 90 is within the throughhole 65 of the slot 75. In said second positon of the cutter blade 90, a cutting or distal edge 95 of the cutter blade 90 abuts/strikes/contacts the anvil 80, i.e. when the anvil 80 is in the anvil second position.

[0083] In this way, movement of the cutter blade 90-from the first position to the second position thereofcauses the cutter blade 90 to cut/slice through the cable 10 entrapped within the throughhole 65 of the cutter slot 75. It will be appreciated from the above that, in use, the cutter arrangement 20 acts as a guillotine for cutting a cable 10.

[0084] The throughhole 65 is distal or spaced from said anvil 80 second position, e.g. when viewed along a direction of the centre line C. Such arrangement provides that the anvil 80 can be deployed, e.g. moved from said anvil 80 first position to said anvil 80 second position without touching the cable 10 retained in the throughhole 65.

[0085] There is provided an arrangement or means 76 for guiding a cable 10 into the slot 75 as the grabber arrangement 15 or grabber elements 30 close around the cable 10, e.g. as the grabber elements 30a, 30b move from the first (open) position to the second (closed) position. Guide arrangement 76 comprises guide plates 77 provided on each side of the slot 75.

[0086] The arrangement for moving the grabbing elements 30 comprises a first motive arrangement, which typically comprises a first hydraulic drive cutter body. The arrangement for moving the cutter body 70 comprises a second motive arrangement, which typically comprises a second hydraulic drive. The arrangement for moving the anvil 80 comprises a third motive arrangement and typically comprises a third hydraulic drive. The arrangement for moving the cutter blade 90 comprises a fourth motive arrangement or means, which may comprise a fourth hydraulic drive.

[0087] The present invention also provides an apparatus, such as a grabber and/or cutter apparatus, such as an underwater cable grabber and cutter apparatus generally designated 99. The apparatus 99 comprises at least one grabber and cutter tool 5.

[0088] The grabber and cutter apparatus 99 comprises one or more line and/or wires 100,105. The one or more lines and/or wires 100, 105 comprises a lifting wire 100 and an orientation line 105. In use, the lines and/or wires 100, 105 extend from a vessel (not shown) or the like to the at least one grabbing and cutting tool 5. An orientation arm 110 is also provided.

[0089] The present invention also provides a method of grabber and/or cutting a cable 10, conduit, pipe or the like, such as an underwater cable, conduit or pipe, comprising the steps of: [0090] providing at least one tool 5; [0091] positioning said tool 5 adjacent a cable 10.

[0092] The method comprises grabbing the cable 10 with the grabbing arrangement 15. The method comprises cutting the cable 10 with the cutter arrangement 20.

[0093] The disclosed first embodiment of the present invention will now be further described with reference to FIGS. 1 to 10(E).

[0094] The tool 5 is typically deployed from a crane or winch, suspended over a side or rear of a vessel (ship) from a lifting wire 100. An orientation line (or lines) 105 attached to one (or both) of the ends of the orientation arm 110, is (are) operated from a position of the ship to the side of the lifting wire 100, and is (are) used to keep the tool 5 in a correct orientation across the cable 10 in order to correctly engage such. Alternatively, the tool 5 can be fitted with a thruster or thrusters to keep the tool 5 correctly oriented. Alternatively, ROV handles can be fitted to the tool 5 so that a free-flying ROV can latch onto the tool 5 and manoeuvre such into place. Sonar and/or video cameras can be mounted to front and rear sides of the tool 5 to aid guidance onto the cable 10 or video feed from a free-flying ROV can be used for such purpose.

[0095] The tool 5 is lowered over the cable 10 with the grabber arrangement 15 in the open positionsee FIG. 3. The wide opening of the grabber elements 30a, 30b grabber arms, allow for easy positioning of the tool 5 over the cable 10 with a wide margin for error. This is in contrast to endeavouring to position the cutter arrangement 20 and cable 10 together, and preventing the cable 10 from popping out of the cutter slot 75 while the anvil 80 is being deployed, something not easily achieved subsea, particularly at depth, during even mild swells, or in areas of current.

[0096] The grabber elements 30a, 30b or grabber tines, which can be hydraulically operated, are then closed capturing the cable 10see and FIG. 10(A). The guide plates 77 create an open angle of not less than 85 between the grabber tines 30 and a grabber base plate 62 to ensure that the cable 10 does not become pinched between grabbing elements 30a, 30b and the base plate 62 of the tool 5, and that the cable 10 is manoeuvred successfully into a correct position for engaging in the cutter arrangement 20see FIG. 5.

[0097] Up to this point, a trolley 63 onto which the cutter arrangement 20 is mounted, is held in a distal (high) positon by a force of a hydraulic cylinder 64, which at this stage is in an extended position.

[0098] The trolley 63 is now slid (downwards) along guide rails 66, either by application of hydraulic pressure to retract the hydraulic cylinder 64 or under the force of gravity with the removal of hydraulic pressure acting to extend the hydraulic cylinder 64, till the cable 10 is in contact with a top portion 67 of the cutter slot 75see FIGS. 6 and 10 (C).

[0099] The anvil 80 is then deployed, sliding across a base/jaw/mouth of the cutter slot 75 and engaging in an aperture in an opposite side of the cutter slot 75see FIGS. 7 and 10(d). The arrangement of the tool 5 seeks to ensure that the cable 10 is as far above the anvil 80 as possible while the anvil 80 is being deployed. This seeks to ensure that the anvil 80 will not contact the cable 10 as the anvil 80 is being deployed, a scenario which could lead to jamming or incomplete engagement of the anvil 80, which would lead to failure to cut the cable 10.

[0100] The hydraulic cylinder 64 is then put into a free float condition, where a hydraulic fluid is allowed to pass freely from one side of the cylinder piston to the other. The cylinder 64, therefore, produces little resistance to movement of the trolley 63. The cutter blade 90 is then deployed. The cutter blade 90 is in this embodiment hydraulically operated. As the cutter blade 90 engages with the cable 10, a force of the cutter blade 90 pushes the entire cutter arrangement 20 and trolley 63 upwards till the anvil 80 meets the cable 10, FIGS. 8 and 10(D). At this point the cable 10 is now clamped between an anvil 80 and cutter blade 90, and the cutter blade 90 cuts through the cable 10, FIGS. 9 and 10(E).

[0101] As the grabber arrangement 15 is rigidly connected to the cutter arrangement 20 along the axis of the cable 10, there is no risk of lateral forces on the cutter blade 90, which could otherwise result in a broken blade and/or failure to achieve the cut.

[0102] Once the cut of the cable 10 is complete, the entire tool 5 is recovered to surface with the grabber arrangement 15 still holding one end of the newly cut cable 10see FIG. 10(e).

[0103] Referring now to FIG. 11, there is shown a grabber and cutter tool, generally designated 205, according to a second embodiment of the present invention. The tool 205 is similar in many respects to the tool 5 of FIG. 1, like parts being designated with like numerals, but iterated by 200. However, the tool 205 of FIG. 11 does not include guide plates.

[0104] When a relatively small diameter cable 210 is captured in a relatively large grab, there is a risk of the cable 210 becoming trapped between the grab elements 230a, 230b and grabber base plate 262 before it is in line with the cutter slot 275, as can be seen from FIG. 11. This prevents the cutter 220 from being able to slide into place. This is due to the acute angle between the grab elements 230a, 230b the grabber base plate 262.

[0105] Referring now to FIGS. 12(A) to (D), there is shown a grabber and cutter tool, generally designated 305, according to a third embodiment of the present invention. The tool 305 is similar in many respects to the tool 5 of FIG. 1, like parts being designated with like numerals, but iterated by 300. Unlike the tool 205, the tool 305 has guide plates 377. The guide plates 377 maintain an open angle between the grabber elements 330 and the main body 340. Therefore, unlike the tool 205, in the tool 305 the cable 310 is not liable to get trapped off-centre due to the acute angle between the grabber elements 335a, 335b and main body 340.

[0106] Referring now to FIGS. 13(A) to (C), there is shown a series of views of a cutter arrangement 20, 220, 320 capable of use in any of the first to third embodiments of FIGS. 1 to 10(D), FIG. 11, or FIGS. 12(A) to (D), respectively.

[0107] Referring now to FIGS. 14(A) and (B), there is shown a grabber and cutter tool, generally designated 405, according to a modified embodiment of the present invention. The tool 405 is similar in many respects to the tool 5 of FIG. 1, like parts being designated with like numerals, but iterated by 400.

[0108] The tool 405 comprises main body 440 from which the first and second grabber elements 430a, 430b movably/pivotably depend. A gripper arrangement 495 is provided between the first and second grabber elements 430a, 430b, on the main body 440. The gripper arrangement 495 faces into and/or comprises part of the throughhole 465 or closed space. The gripper arrangement 495 comprises a plurality of teeth 496, which in this embodiment are arranged in a plurality of rows.

[0109] In use, the gripper arrangement 495 contacts and grips/restrains a cable, conduit, pipe or the like held within the throughhole 465.

[0110] The tool 405 is typically used towards the cut end of a cable. As the cable is being retrieved to surface, imbalanced forces from the cable weight tend to act to try and pull the cable through the grabber jaws 455. This may be the case even if after a cut is made the tool 405 is repositioned some distance from the cut, particularly in deep water where it may not be practical to move the grab location far enough from the cut to ensure balanced forces all the way to surface. To resist these forces, an optional gripper arrangement 495 (gripper plate) consisting of a series of smaller toothed plates is installed on a base of the tool 405. As the cable is grabbed by the first and second grabber elements (430a, 430b) or tines and pressed upwards onto the gripper plate arrangement 495, the teeth 496 partially penetrate into an outer coating of the cable, thus greatly increasing the resistance of the tool 405 to longitudinal forces acting on the cable.

[0111] In preferable embodiments there can be between two and six rows of teeth, e.g. 30 mm to 70 mm apart, each row consisting of thirty to fifty teeth, each tooth typically being 5 mm to 20 mm high, 10 mm to 40 mm long, and 5 mm to 15 mm wide. FIG. 14(B) shows the rows in-line with the direction of the cable, but it will be appreciated that the rows of teeth may be at 90 to the cable.

[0112] It will be appreciated that the embodiments of the invention hereinbefore described are given by way of example only, and are not meant to be limiting to the scope of the invention. It will be appreciated that while the disclosed embodiments describe grabbing and cutting of a cable or underwater cable, other elongate articles, e.g. conduits, pipes or the like may also be grabbed and cut by tools according to the present invention.