FR2734192A1 - Cutting machine for immersed tubes using abrasive impregnated cutting wire - Google Patents

Abstract

The cutting machine (1), of immersed tubes (5), by a continuous abrasive wire forming a belt (7) and guided by pulleys contains an ability of displacing a straight line part (23) of the tool (7) forming a moving cutting blade, according to curved profile (8) into the form of an arc of a circle. The continuous cutting wire (7) is diamond impregnated and is guided by the pulleys (9,10,11,12) in the horizontal plane and (17,17,21) in the vertical plane.

Description

SUBMERSIBLE TUBE CUTTING MACHINE
BY A FILIFORM ABRASIVE TOOL
The present invention relates to a machine for cutting tubes immersed in a filiform abrasive tool such as a diamond cable forming an endless loop.

 The present invention applies in particular to the cutting of submerged submarine pipes (pipelines), as well as pipes forming part of structures carrying oil platforms constituted by tubes which, generally, comprise a metal part and a concrete part; it is necessary, in particular for dismantling or dismantling operations of oil platforms after the end of their exploitation, to cut in particular the base of the piers on which these platforms rest, which piers are generally embedded or anchored on the seabed .

 The present invention applies in particular to the cutting of production wells (or conductive pipeline), well heads formed by concentric tubes generally comprising annular cemented spaces.

 Already known from US-A-4,487,363 (KUBO) a method and a device for cutting immersed concrete structures, using a diamond cable forming a closed loop which is driven and guided by pulleys I the device described in this document describes a driving part for driving the cable situated on the ground and a system making it possible to maintain the tension of the cable during the progression of the part of the cable (or strand) through the part as and when cutting it.

 The object of the present invention is to provide a simple, compact and easy-to-use machine for cutting submerged tubular elements.

 The object of the present invention is in particular to provide such a machine which can be easily set up in the cutting position of the tubular element located below the water level, and then be easily moved, for example to another tubular element with cut.

 The solution to the problem posed consists in providing a machine for cutting tubes submerged by an endless thread-like abrasive tool such as a diamond cable forming a loop, guided by pulleys, which comprises means for moving a rectilinear portion of the cable forming a sliding leading or cutting edge, according to a curvilinear profile in an arc; these means are preferably produced by providing a machine which has a structure articulated along an axis of articulation which is perpendicular to the longitudinal axis of said tube, which articulated structure carries pulleys for guiding said cable.

According to a preferred embodiment, said machine for cutting a submerged tube using an elongated abrasive tool forming an endless loop, comprises
a fixed main structure capable of being immobilized relative to said tube by articulated arms or fingers enclosing a portion of said tube, which arms or fingers are articulated along an axis of articulation parallel to the longitudinal axis of said tube to be cut,
a secondary structure articulated with respect to said main structure fixed along an axis of articulation which is perpendicular to the longitudinal axis of said tube, which secondary structure articulated carries pulleys for guiding and driving said elongated abrasive tool forming a loop without end, which extends substantially in two planes forming between them an angle close to 90 '(preferably to within 90).

According to particular embodiments
- the cable in the form of a closed loop comprises a first part which extends in a first plane and comprises a second part which extends in a second plane, which first plane and second plane define (make between them) a value angle preferably fixed constant between 60 and 120 degrees
- Said machine comprises four pulleys for guiding said cable in a first plane, further comprises two pulleys for deflection and a driving pulley and for guiding said cable in a second plane; the axis of intersection of said second plane with said first plane is parallel to the pivot axis of a pivoting (or articulated) structure (or part) of said machine which receives said pulleys
- Said machine comprises a first structure, called fixed structure or main structure, which is capable of being immobilized relative to the tube to be cut by fingers or articulated arms, the number of which is preferably at least equal to three, for example equal four, which fingers or arms are articulated along an axis of articulation parallel to the longitudinal axis of the tube to be cut, so that which fingers or arms articulated can come to bear on the external surface of the tube to be cut, in order to '' immobilize the main structure relative to this tube
- Said machine comprises a fixed or main structure provided with means (such as a hook) for attaching or suspending said machine by means of said main structure to handling slings allowing movement under the surface of the water from said machine by a lifting device placed for example on the surface, or by means of a submarine type wire guide (or ROV - in English: "Remote Operated Vehicle") coming to moor or fix on said main structure of a substantially neutral leg in order to move it to its fixing location ;;
- Said machine comprises means for controlling and / or adjusting the tension of the abrasive filiform tool, by the displacement of at least one of said guide pulleys (or driving or deflection) of said filiform tool
- Said machine comprises a driving pulley driven by a hydraulic or pneumatic motor integrated into said machine, which motor is supplied with pressurized fluid by a flexible pipe (or umbilical) which connects said motor (and, where appropriate, cylinders of actuation of said articulated fingers or arms and of the articulation of said structures relative to one another, as well as the tension adjustment cylinder of said abrasive filiform tool) to a pump or source of hydraulic energy.

 The invention provides a device or module which can be easily set up and temporarily fixed to the tubular element to be cut, for example under the control of plungers located near the machine and controlling the positioning of the machine on the tubular element to be cut, as well as its removal once the element has been cut, the implementation of the machine according to the invention can also be carried out using an underwater vehicle, whether inhabited or not, allowing also local, visual control or via video cameras integrated or not in the machine or module in particular.

 The machine according to the invention is very simple, very compact and very easy to implement for cutting a stack or a vertical tube and makes it possible in particular to require a search or excavation of very reduced volume, when cutting 'A pile supporting an oil platform is desired, according to a cutting section which can be located under the profile of the seabed thanks to the cutting in a semicircle, allowing such a search of very reduced or reasonable dimensions.

 The machine according to the invention can easily be capable of fixing and cutting tubes of different dimensions (diameters), whether the tube is in a horizontal, vertical or inclined position.

 The numerous advantages provided by the invention will be better understood through the following description which refers to the appended drawings which illustrate without any limiting character preferred embodiments of machines for cutting submerged tubes according to the invention.

 Figure 1 illustrates in side view an embodiment of a cutting machine according to the invention. In FIG. 1, the articulated element carrying the diamond cable extending in the form of a closed loop, is shown in solid lines in a position corresponding to the end of the cutting operation of the tubular element, and is also represented in dotted lines in a position corresponding either to a position prior to the start of the cut, or to a position of disengagement of the tool relative to the tubular element when the tool is removed and / or machine.

 Figure 2, which is a view along 11 of Figure 1, illustrates by a plane perpendicular to the longitudinal axis of the tubular element to be cut, the machine illustrated in Figure 1.

 Figure 3 illustrates in a side view in another plane the machine of Figures 1 and 2 and is a view along III of Figure 1.

 Figure 4 partially illustrates the machine of Figures 1 to 3, and is a view along IV of Figure 3, and more particularly illustrates the means of displacement of the deflection pulleys allowing the modification of the tension of the abrasive filiform tool, preferably consisting of a diamond wire.

 Figures 5 to 7 schematically illustrate in side view, the steps for implementing a machine according to the invention for cutting the base of a pile buried at the bottom of the sea.

 Figure 8 schematically illustrates in perspective view the configuration of a diamond cable and the pulleys for guiding and driving this cable in a machine according to the invention.

 With reference to FIGS. 1 and 8 more particularly, the filiform abrasive tool, preferably consisting of a diamond wire generally identified by the number 7, extends and / or is formed in a closed loop which extends substantially in two planes 31 and 30 forming an angle between them 62, for example close to 90 '; this configuration of the loop extending in two planes makes it possible to significantly increase the compactness of the device I as illustrated diagrammatically in FIG. 8, the cable 7 comprises a strand or a section 23 called attack or cut , extending straight and guided by two pulleys, namely a front left pulley 9 and a right front pulley 10.

 The cable 7 also includes a strand or a left lateral section 25, guided by said pulley 9 and a pulley 12 at the rear left; in the same way, a right lateral section 24 of the cable is guided by said pulley 10 and a right rear pulley 11; the pulleys 9, 10, 11, 12 extend substantially in said plane 30, so as to guide said cable 7, that is to say the strands 23, 24, 25 in said plane 30; the device also comprises two pulleys 17 and 18 of deflection extending substantially in a second plane 31, as well as said driving pulley 21; said pulleys 17, 18 and 21 have their respective axes of rotation 32, 33, 22 parallel to each other and perpendicular to said plane 31, while said pulleys 9 to 12 have their respective axes of rotation (marked 13 to 16, Figures 1 and 2 ) parallel to each other and perpendicular to said plane 30.

 It can be seen that said return pulleys 17 and 18 are located outside the loop formed by said cable, unlike said guide pulleys 9 to 12 and said drive pulley 21 on the other hand.

 The distance 65 measured edge to edge between said front guide pulleys 9 and 10, is sufficient to allow the passage of the tube as it is cut, and is therefore greater than the outside diameter of the tube to be cut.

 As illustrated in FIGS. 5 to 7 in particular, the submarine mobile device for cutting submerged tubes is essentially constituted by a main structure 2 and a secondary or articulated structure 3, which is articulated with respect to the main structure 2 according to a articulation axis 4 perpendicular to the longitudinal axis 6 of the tube 5 to be cut.

 As illustrated in these Figures, the cutout according to a circular arc 8, or more precisely according to a portion of cylinder extending along said articulation axis 4, in particular in the case where the tubular element is constituted by the base of a stack forming a support for an oil platform for example, that is to say a tubular element embedded in the sea floor 69, makes it possible to execute before cutting and fixing the machine on the base of the tubular element, an excavation 66 or excavation of small dimension and therefore of small volume, below the current level 70 of the seabed 69.

 Cutting into an arc 8 or made according to said portion of cylinder of axis 4, is made possible by the articulation of the articulated structure 3, along said axis 4, which articulated structure 3 carries said cable 7 guided by said pulleys fixed to said articulated structure 3.

 As illustrated in these FIGS. 5 to 7, the set of actuators, preferably hydraulic, which are integrated into said machine, is supplied by a flexible or umbilical pipe 67, connecting said actuators to a source of hydraulic energy or a pump located in an installation (not shown) generally located above the surface of the water.

The umbilical 67 is used to perform the following functions
1) Hydraulic power supply to the hydraulic motor,
2) Allow remote control and modification of the means of
cable tension regulation,
3) Supply electric power to projectors and cameras
mounted on part 3 of the cutting machine,
4) Surface reproduction of video images from various cameras,
5) Restitution on the surface of the indications of various sensors
(pressure, positioning ...).

 As illustrated in FIG. 6, said main structure 44, 2 of the cutting machine can be manipulated by an offset lifting device (not shown), for example a lifting device situated above the surface of the water, by through slings 68 shown in Figure 5.

 The schematic sequence of setting up the device on the tubular element shown in Figures 5 to 7, shows Figure 5, the approach of the machine 1 of the base of the tubular element 5, after the excavation 66 has been carried out. FIG. 6 shows the phase of attachment of the machine to the tubular element 5 by means of articulated fingers or arms 36, 37 forming part of the main structure 44, 2.

 Figure 7 illustrates the tube cutting machine in a position fixed to the tube 5 by said fingers or articulated arms at the end of the cutting operation of the tubular element I the clearance of the device from the element tubular 5 is carried out substantially according to reverse operations to those of its establishment.

 The operations illustrated in FIGS. 5 to 7 can be carried out under the control of divers or of a manned or unmanned underwater vehicle, which are located in contact with or near the cutting machine.

With reference to Figures 1 and 2 in particular, the main or fixed structure 2 of the machine may for example be constituted by a rigid assembly of metal parts welded together; this main structure 2, 44 notably comprises a sheet cut out in the shape of a "V", so as to allow contact at points marked 57,
Figure 2, of the structure against the outer wall of the tube 5 to be cut when tightening the fingers or articulated arms allowing the temporary fixing and / or immobilization of the machine around the tube; the tube 5 can for example be constituted by several coaxial cylindrical layers Sa, 5b, 5c metallic and / or concrete for example, extending along the longitudinal axis 6 of the tube.

 The main metal structure 44, 2 of the machine comprises bearings allowing rotation or pivoting along axes 42 and 43 parallel to the longitudinal axis 6 of the tube, of sets in the form of forks 38 and 39 respectively left and right, each fork-shaped assembly being for example constituted by a rigid assembly of two fingers or arms 36 and 37 parallel to each other, whose free front ends 40 and 41 respectively can come to bear on the outer face of the tube 5, so as to allow the main structure 2, 44 of the machine to be clamped around the tube and its immobilization during the cutting of the latter.

 The fingers or arms 36, 37 each constituting the fork-shaped assemblies 38 and 39, are actuated by a jack 56 to pivot around said respective axes 42, 43, for example symmetrically with respect to a plane 64 of general symmetry of the device.

 It can be seen in particular in Figure 1 that said main structure 2, 44 of the device also comprises pivoting bearings along an axis 4 perpendicular to the longitudinal axis 6 of the tube 5, of part 3 of the device located below on the Figure 1, which is articulated with respect to the main part 2.

 The articulated structure 3 can for example be constructed from sections of metal tubes (marked 49, 50, 52, 53, 58, 59, Figures 1 to 3) assembled together by welding or by a flange system 51 shown in Figure 1 , allowing easy disassembly (separation) of the two main structures (parts) of the machine.

 The displacement along an axis 4 rotation of the articulated part 3 relative to the main part 2 of the machine, is obtained by means of a jack whose body 45 is pivotally mounted along an axis 47 relative to the main structure 2 and whose free end of the rod 46 is pivotally mounted with respect to an arm 50 of the articulated part 3 of the structure, which cylinder 45, 46 is preferably hydraulically actuated to rotate the articulated structure 3 of the position shown in solid lines in Figure 1 to the position shown in dotted lines in the same Figure, when disengaging the tool after cutting the tube 5, ct to perform the reverse movement when cutting the tube 5.

 With reference to Figures 3 and 4, said deflection pulleys can move to allow adjustment of the cable tension between a position shown in solid lines in these Figures, and a position shown in dotted lines in these Figures.

 More specifically, the return pulley marked 18 in Figure 8 in particular, can pass from a position marked 18a in Figure 3 corresponding to the position 33a (Figure 4) of its axis of rotation, to a position marked 18b in Figure 3 and corresponding to the position marked 33b (Figure 4) of its axis of rotation, under the effect of the displacement along the axis 60 of the rod z5 of a jack 35, the end of which carries via a bearing the shaft of said pulley 18; said jack 35, the body 54 of which is fixed to the tubular section 53 forming part of the articulated structure 3, is preferably hydraulic and includes regulation means making it possible to adjust the tension of the cable, for example to keep it constant or as and as the tubular element is cut by said cable, causing in particular a heating thereof and its deformation, as well as induced tensions which can cause it to break.

 Similarly, a device, for example manual adjustment of the initial tension of the cable, can be obtained by means 34 shown diagrammatically in Figures 3 and 4, allowing the pulley marked 17 in Figure 8 to pass through. a position marked 17a in dotted lines corresponding to the position marked 32a (Figure 4) of its axis of rotation, to a position marked 17b in Figure 3 corresponding to a position marked 32b in Figure 4 of its axis of rotation.

Correlatively, the strands or parts 28, 29 of the cable 7 illustrated
Figure 8, pass from a position marked 28a, 29a to a position marked 28b, 29b under the action of means 34, 35 for manual and hydraulic adjustment of the cable tension.

 It can also be seen in FIGS. 2 to 4 that the articulated structure 3 is preferably symmetrical with respect to said plane 64 and constituted by arms, themselves constituted by sections of tubes linked together by welding or by clamping, which arms comprise bearings allowing the rotation of said guide and return pulleys 9 to 12, 17, 18, as well as the driving pulley 21.

Claims (10)

 1. Machine (1) for cutting tubes (5) immersed by an endless filiform abrasive tool (7) forming a loop and guided by pulleys, characterized in that it comprises means for moving a rectilinear portion (23) of said tool (7) forming a scrolling cutting strand, according to a curvilinear profile (8) in an arc.  2. Machine (1) for cutting a submerged tube (5) using a diamond cable (7) forming an endless loop, characterized in that it comprises a structure (3) articulated along an axis (4 ) hinge which is perpendicular to the longitudinal axis (6) of said tube (5), which articulated structure (3) carries guide pulleys of said cable.  3. Machine according to any one of claims 1 or 2 wherein said tool or cable (7) in the form of a closed loop has a first part (23, 24, 25, 26, 27) which extends in a first plane (30) and comprises a second part (28, 29) which extends in a second plane (31), which first plane and second plane define an angle (62) of value between 60 and 120 degrees.  4. Machine according to any one of claims 1 to 3 comprising four pulleys (9, 10, 11, 12) for guiding said cable in a first plane (30), further comprising two pulleys (17, 18) for deflection and a pulley (21) driving and guiding said cable (7) in a second plane (31), and in which the axis (61) of intersection of said second plane with said first plane is parallel to the axis (4) pivoting a pivoting structure (3) which receives said pulleys, drive, guide and return.  5. Machine according to any one of claims 1 to 4, comprising a main structure (2), capable of being immobilized relative to the tube to be cut by articulated fingers (36, 37) along a hinge axis (42 , 43) parallel to the longitudinal axis (6) of the tube to be cut.  6. Machine according to any one of claims 1 to 5, comprising a fixed or main structure (2, 44) provided with means for suspending said machine from slings (68) for handling under the surface of the water of said machine by a lifting device or other means of handling in situ.  7. Machine according to any one of claims 1 to 6, comprising means (34, 35) for controlling and / or adjusting the tension of the tool or cable, by moving at least one of said pulleys.  8. Machine (1) for cutting a submerged tube (5) using an elongated abrasive tool (7) forming an endless loop, which comprises  - a fixed main structure (1) capable of being immobilized with respect to said tube by articulated arms or fingers (36, 37) enclosing a portion of said tube, which fingers or arms (36, 37) are articulated along an axis of articulation (42, 43) parallel to the longitudinal axis (6) of said tube to be cut,  - a secondary structure (3) articulated with respect to said fixed main structure (1) along an axis (4) of articulation which is perpendicular to the longitudinal axis (6) of said tube (5), which secondary structure (3) articulated carries pulleys (9, 10, 11, 12, 17, 18, 21) for guiding and driving said abrasive tool which extends substantially in two planes (30, 31) forming an angle (62) between them between 60 and 120 '.  9. Machine according to any one of claims 1 to 8, comprising a driving pulley (21) driven by a hydraulic motor integrated into said machine, which motor is supplied with pressurized fluid by a flexible pipe (67).  10. Machine according to any one of claims 3 to 9, wherein said angle (62) has a value close to 90 '.