UNDERWATER PIPELINE SUPPORT, AND SYSTEM AND METHOD FOR SETTING UP SUCH A SUPPORT

Abstract

A support for an underwater pipeline, in particular configured to elevate an underwater pipeline on a bed of a body of water, with a connecting frame configured to fit to a portion of underwater pipeline extending along a longitudinal axis; and at least two legs, which are hinged to the connecting frame, and movable between a contracted configuration and an extended configuration in which they extend crosswise to the underwater pipeline to rest on the bed of the body of water.

Claims

1-24. (canceled)

25: An underwater pipeline support for an underwater pipeline comprising: a connecting frame extending along a first axis, said connecting frame configured to fit to a portion of a pipeline extending along a longitudinal axis, wherein when fitted, the first axis is substantially parallel to the longitudinal axis of the pipeline; and a leg moveably connected to the connecting frame about a second axis, said leg being movable from a contracted configuration to an extended configuration in which said leg extends crosswise to the pipeline to rest on a bed of a body of water.

26: The underwater pipeline support of claim 25, wherein the second axis is crosswise to the first axis such that, in the contracted configuration, the leg is substantially parallel to the underwater pipeline.

27: The underwater pipeline support of claim 25, wherein the connecting frame comprises a gripping member and a hub configured to support the leg and mounted to rotate relative to the gripping member.

28: The underwater pipeline support of claim 25, further comprising a foot configured to rest on the bed of the body of water, wherein said foot is moveably connected to an end of the leg about a third axis, and said foot is movable from a contracted position in which said foot is substantially parallel to the leg to an operational position in which said foot extends crosswise to the leg.

29: The underwater pipeline support of claim 25, wherein a length of the leg is adjustable.

30: The underwater pipeline support of claim 29, wherein the leg comprises an adjusting mechanism configured to cause an adjustment of the length of said leg.

31: The underwater pipeline support of claim 30, wherein the adjusting mechanism comprises a power take-off connection.

32: The underwater pipeline support of claim 30, further comprising at least one sensor configured to detect a signal related to a load applied along said leg.

33: The underwater pipeline support of claim 25, further comprising a stop device configured to arrest the leg in the extended configuration.

34: The underwater pipeline support of claim 33, wherein the stop device comprises: a guide; a runner movable along the guide; an arm hinged to the runner and to the leg; and a non-return mechanism located along the guide and configured to form a coupling with the runner.

35: The underwater pipeline support of claim 25, wherein said leg is moveably connected to the connecting frame such that a transition from the contracted configuration to the extended configuration occurs by gravity following a release of a free end of said leg.

36: The underwater pipeline support of claim 25, further comprising an opening mechanism configured to move the leg from the contracted configuration to the extended configuration.

37: The underwater pipeline support of claim 36, wherein the opening mechanism comprises a screw and a nut screw movable along the screw and connected to the leg.

38: The underwater pipeline support of claim 37, wherein the opening mechanism comprises a hydraulic cylinder comprising a rod connected to the leg.

39: The underwater pipeline support of claim 38, wherein the opening mechanism comprising an automatic device configured to activate the hydraulic cylinder based on a pressure in the body of water.

40: The underwater pipeline support of claim 39, wherein the opening mechanism comprises: a reservoir; a valve between the reservoir and the hydraulic cylinder; a pressure sensor; and a transducer configured to open the valve based on a pressure value.

41: The underwater pipeline support of claim 25, wherein the leg is hinged to the connecting frame about the second axis.

42: The underwater pipeline support of claim 25, further comprising at least two legs moveably connected to the connecting frame about at least two respective second axes, each leg being movable from a contracted configuration to an extended configuration in which said leg extends crosswise to the pipeline to rest on the bed of the body of water.

43: The underwater pipeline support of claim 42, further comprising at least two feet, each foot being configured to rest on the bed of the body of water, wherein each foot is moveably connected to an end of a respective leg about a third axis, and each foot is movable between a contracted position in which said foot is substantially parallel to the respective leg, and an operational position in which said foot extends crosswise to the respective leg.

44: An underwater pipeline laying system comprising: a laying vessel; and a crane configured to, within a predetermined area on a bed of a body of water, fit a support to a designated portion of an underwater pipeline on the laying vessel, said support comprising: a connecting frame extending along a first axis, said connecting frame configured to fit to the designated portion of the underwater pipeline extending along a longitudinal axis, wherein when fitted, the first axis is substantially parallel to the longitudinal axis of the pipeline; and a leg moveably connected to the connecting frame about a second axis, said leg being movable from a contracted configuration to an extended configuration in which said leg extends crosswise to the pipeline to rest on the bed of the body of water.

45: The underwater pipeline laying system of claim 44, further comprising a lock member configured to keep the support in the contracted configuration, wherein the lock member is selectively removable to enable the support to assume the extended configuration.

46: The underwater pipeline laying system of claim 44, further comprising an underwater vehicle configured to, at least one of, assist laying of the support and/supply power to the support.

47: The underwater pipeline laying system of claim 44, wherein the leg is hinged to the connecting frame about the second axis.

48: The underwater pipeline laying system of claim 44, wherein the support comprises at least two legs moveably connected to the connecting frame about at least two respective second axes, each leg being movable from a contracted configuration to an extended configuration in which said leg extends crosswise to the pipeline to rest on the bed of the body of water.

49: A method of setting up an underwater pipeline support comprising: fitting a support to a designated portion of an underwater pipeline on a laying vessel, wherein said support comprises a connecting frame extending along a first axis, said connecting frame configured to fit to the designated portion of the underwater pipeline extending along a longitudinal axis fitting a lock member configured to keep the support in a contracted configuration, wherein when the lock member is fitted, the first axis is substantially parallel to the longitudinal axis of the underwater pipeline; launching the underwater pipeline and the support from the laying vessel into a body of water; and laying the support on a predetermined area of a bed of the body of water, wherein the support comprises a leg moveably connected to the connecting frame of the support about a second axis, wherein when the support is laid on the predetermined area of the bed of the body of water, said leg has assumed an extended configuration in which said leg extends crosswise to the underwater pipeline to rest on the bed of the body of water.

50: The method of claim 49, further comprising releasing the lock member after the support is in the body of water to enable the support to assume the extended configuration.

51: The method of claim 49, further comprising adjusting a height of the support after the support is laid on the bed of the body of water.

52: The method of claim 51, further comprising: acquiring at least one signal related to a load exchanged between the underwater pipeline and the bed of the body of water, and adjusting the height of the support based on said acquired signal.

53: The method of claim 52, further comprising: acquiring a signal related to a load on the leg, and adjusting a length of the leg based on the acquired signals.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Further characteristics and advantages of the present disclosure will become clear from the description below of certain embodiments, with reference to the figures in the accompanying drawings, in which:

[0044] FIG. 1 is an elevation view, with parts shown schematically and parts removed for clarity, of a system configured to lay an underwater pipeline and supports of the underwater pipeline on a bed of the body of water;

[0045] FIG. 2 is a perspective view, with parts removed for clarity and on an enlarged scale, of a support in FIG. 1 in an extended configuration;

[0046] FIG. 3 is an elevation view, with parts removed for clarity, of a variant of the support shown in FIG. 2;

[0047] FIG. 4 is an elevation view, with parts removed for clarity and on an enlarged scale, of a support in FIG. 1 in a contracted configuration;

[0048] FIG. 5 is an elevation view, with parts removed for clarity, parts in section and on an enlarged scale, of the support in FIG. 1 in an extended configuration;

[0049] FIG. 6 is an elevation view, with parts removed for clarity, parts in section and on an enlarged scale, of the support in FIG. 1 in a contracted configuration;

[0050] FIG. 7 is an elevation view, with parts removed for clarity, parts in section and on an enlarged scale, of the support in FIG. 1 in an extended configuration;

[0051] FIG. 8 is an elevation view, with parts removed for clarity and parts in section, of a second embodiment of the support in FIG. 1;

[0052] FIG. 9 is an elevation view, with parts removed for clarity and parts in section, of a third embodiment of the support in FIG. 1;

[0053] FIG. 10 is an elevation view, with parts removed for clarity and parts indicated schematically, of a third embodiment of the present disclosure; and

[0054] FIGS. 11 and 12 are elevation views, with parts removed for clarity and parts shown schematically, of two variants of the supports in FIG. 1.

DETAILED DESCRIPTION

[0055] Referring now to the example embodiments of the present disclosure illustrated in FIGS. 1 to 12, referring to FIG. 1, a system 1 is shown, as a whole, for laying an underwater pipeline 2 on a bed 3 of a body of water 4.

[0056] The system 1 comprises a laying vessel 5 assigned to launching and laying the underwater pipeline 2; and an underwater vehicle 6 mainly assigned to controlling the steps of launching and/or laying the underwater pipeline 2.

[0057] The underwater pipeline 2 extends along a longitudinal axis A, is made by joining steel tubes assembled together on board the laying vessel 5, and is covered by at least a layer of polymer material.

[0058] The laying vessel 5 comprises a floating structure 7; a launching ramp 8 hinged to the floating structure 7; a crane 9 arranged along the floating structure 7; and a braking device 10 configured to control the release of the underwater pipeline 2.

[0059] The system 1 also has the function of laying at least one support 11 configured to support the underwater pipeline 2 in an elevated position with respect to the bed 3 of the body of water 4.

[0060] In the case shown in FIG. 1, the bed 3 of the body of water 4 comprises an irregular bathymetric profile with ridges 12 and depressions 13. In general, the morphology of the part of the bed 3 shown is characterized by abrupt bathymetric variations.

[0061] The system 1 envisages fitting one or more supports 11 on the underwater pipeline 2 via the crane 9 on board the laying vessel 5 and laying the support 11 on the bed 3 through the controlled release of the underwater pipeline 2. In other words, the underwater pipeline 2 is the tool through which the correct positioning of the supports 11 is controlled. The quantity or number of supports 11 fitted on the underwater pipeline 2 depends on the span of the depressions and the structural characteristics of the underwater pipeline 2.

[0062] The support 11 has a variable configuration and is able to pass from a contracted configuration (FIGS. 4 and 6) to an extended configuration (FIGS. 5 and 7). The contracted configuration enables the support 11 to be easily stored and transported, especially along the launching ramp 8. The extended configuration is the operational configuration in which the support 11, resting on the bed 3, sustains the underwater pipeline 2.

[0063] The transition from the contracted configuration to the extended configuration occurs along the spanned portion of the underwater pipeline 2 between the launching ramp 8 and the bed 3 of the body of water 4.

[0064] Referring to FIG. 2, each support 11 is shaped like a foldable trestle and comprises a connecting frame 14 configured to be fitted to a portion of the underwater pipeline 2; and two legs 16, which are hinged to the connecting frame 14 and movable between a contracted configuration and an extended configuration in which they extend crosswise to the underwater pipeline 2 to rest on the bed 3 of the body of water 4 (FIG. 1).

[0065] In particular, the connecting frame 14 comprises a gripping member 15A, which extends around an axis A1 and can be coupled to the underwater pipeline 2 so as to substantially align axes A and A1, and a hub 15B, which is coupled to the gripping member 15A in a rotatable manner about axis A1 and supports the legs 16. In consequence, the hub 15B and the legs 16 can rotate about the longitudinal axis A of the underwater pipeline 2.

[0066] Each leg 16 has one end hinged to the hub 15B about an axis A2 crosswise to longitudinal axis A and to axis A1, such that in the contracted configuration (FIG. 4), each leg 16 can be arranged parallel to the underwater pipeline 2. Axis A1 and each axis A2 lie on respective mutually perpendicular planes, such that in the contracted position, each leg 16 can be arranged substantially parallel to axis A1, while in the extended configuration, the leg extends mainly in the radial direction with respect to axis A1.

[0067] Each leg 16 has another end hinged to a foot 17 about an axis A3 substantially parallel to axis A2. In the contracted position (FIG. 4), each supporting foot 17 is arranged substantially parallel to the respective leg 16, while in the extended position, each supporting foot extends crosswise to the respective leg 16. When the support 11, in the extended configuration, is rested on the bed 3 (FIG. 1), each foot 17 turns about axis A3, so as to adapt itself to the configuration of the bed 3.

[0068] Referring to the variant in FIG. 3, the support 11 comprises four legs 16 subdivided into two pairs of legs 16. Each pair of legs 16 is hinged to the hub 15B and to a supporting foot 17 and, together with the hub 15B and the supporting foot 17, forma an articulated quadrilateral.

[0069] Referring to FIG. 1, each support 11 is fitted on the underwater pipeline 2 upstream of the launching ramp 8 in the contracted configuration and with the legs 16 arranged along the upper part of the underwater pipeline 2 so as not to obstruct the passage of the underwater pipeline 2 along the launching ramp 8. In this step and with reference to FIG. 4, the rotation of the hub 15B about axis A1, the rotation of the legs 16 about axes A2, and the rotation of the supporting feet 17 about axes A3 are prevented by a lock member 18, which in the case shown is defined by a releasable band wrapped around the feet 17 and the legs 16, and which is released once the support 11 is downstream of the launching ramp 8 (FIG. 1). The release of the lock member 18 is controlled by the underwater vehicle 6 (FIG. 1).

[0070] Referring to FIG. 5, the support 11 has a stop device 19 to arrest the legs 16 in the extended configuration. In the case shown, the stop device 19 comprises, for each leg 16, a guide 20 integral with the hub 15B and parallel to axis A1; a runner 21 sliding in the guide 20 parallel to axis A1 an arm 22 having one end hinged to the leg 16 about an axis A4 parallel to axis A2 and the other end hinged to the runner 21; and a non-return mechanism 23 that enables stopping runner 21 in a certain position when resting the support 11 on the bed 3.

[0071] In the case shown, the non-return mechanism 23 is defined by a catch-like mechanical mechanism that, by engaging in a specially provided seat, prevents the runner 21 from returning towards the closed position.

[0072] In accordance with a first embodiment, once the lock member 18 shown in FIG. 4 is removed, the support 11 is able to pass from the contracted configuration to the extended configuration simply under the action of the force of gravity. The removal of the lock member 18 enables the rotation of the hub 15B about axis A1 until the legs 16 are arranged beneath the underwater pipeline 2 (FIG. 5). This rotation is facilitated by the asymmetry of the support 11 about axis A1, even when the support 11 is arranged in the contracted configuration. When the legs 16 and feet 17 are arranged beneath the underwater pipeline 2, their weight causes rotation about axes A3 and A4. The legs 16 will assume a substantially vertical position, while the supporting feet 17, which are hinged at their midpoints, will assume a substantially horizontal position.

[0073] As the portion of underwater pipeline 2 equipped with a support 11 approaches the bed 3, the underwater pipeline 2 reduces its inclination to the horizontal, the legs 16 increase their inclination with respect to the hub 15B, and the runner 21 moves nearer to the non-return mechanism 23 (FIG. 5). Once the runner 21 has engaged the non-return mechanism 23, the legs 16 are arrested in the extended position.

[0074] Referring to the embodiment in FIG. 8, the support 11 comprises an opening mechanism 24 to move the legs 16 from the contracted position to the extended position.

[0075] The opening mechanism 24 comprises a screw 25 and a nut screw 26 connected to the screw 25 and to the runner 21 so that nut screw 26 performs linear movements together with the runner 21 based on the rotation of the screw 25.

[0076] In the case in point, the screw 25 is connected to a reducer 27 equipped with a power take-off connection 28 connectable to the underwater vehicle 6 (FIG. 1), which operates the screw 25 to open the support 11.

[0077] Referring to the embodiment in FIG. 9, the support 11 comprises an opening mechanism 29 that comprises a hydraulic cylinder 30 comprising a rod 31, the free end of which is connected to the runner 21. The hydraulic cylinder 30 is mechanically irreversible and comprises a non-return mechanism integrated in the hydraulic cylinder 30 (not shown in the accompanying figures). In this case, operation of the hydraulic cylinder 30 is also performed by the underwater vehicle 6 (FIG. 1), after setting up a hydraulic connection between the underwater vehicle 6 (FIG. 1) and the hydraulic cylinder 30.

[0078] Referring to the embodiment in FIG. 10, in addition to the opening mechanism 29, the support 11 comprises an automatic device 32 capable of providing the hydraulic cylinder 30 with the pressurized fluid necessary to cause operation of the rod 31.

[0079] In the case shown, the automatic device 32 comprises a reservoir 33 configured to hold a pressurized fluid and hydraulically connectable to the hydraulic cylinder 30; an on-off valve 34; a pressure sensor 35; and a mechanical transducer 36 to operate the valve 34 based on the pressure acting on the sensor 35.

[0080] In practice, the automatic device 32 is able to hydraulically connect the reservoir 33 to the hydraulic cylinder 30 based on the depth of the support 11 in the body of water 4 (FIG. 1) and, therefore, on the pressure of the body of water 4 that acts on the automatic device 32.

[0081] Referring to the variants in FIGS. 11 and 12, each leg 16 is adjustable in length. In fact, each leg 16 comprises two elongated members 37 and 38 telescopically coupled together and an adjusting mechanism 39 connected to both the elongated members 37 and 38.

[0082] In FIG. 11, the adjusting mechanism 39 comprises a screw 40; a nut screw 41; a reducer 42; and a power take-off connection 43 to create a connection with an underwater vehicle 6 (FIG. 1).

[0083] In FIG. 12, the adjusting mechanism 40 comprises a hydraulic cylinder 44, which has a hydraulic connector (not shown in the accompanying figures) configured for connecting to the underwater vehicle 6 in FIG. 1 and of the irreversible type.

[0084] The height adjustment of the legs 16 enables adjusting the height of the support 11 so that the support 11 effectively supports the underwater pipeline 2. Furthermore, adjustment of the length of the legs 16 enables distributing the load of the underwater pipeline 2 between the legs 16 in a balanced manner.

[0085] To this end, the legs 16 are provided with sensors 45 to acquire signals related to the load along the legs 16. In practice, each leg 16 comprises a sensor 45 configured to output a signal related to the load transmitted along the respective leg 16.

[0086] The load-related signals of the respective legs 16 are transmitted to the underwater vehicle 6 (FIG. 1), where a control unit 46 (FIG. 1) compares the signals and outputs control signals to lengthen or shorten one or both of the legs 16 so that the acquired signals fall within a predetermined range.

[0087] Finally, it is evident that variants can be made to the present disclosure with respect to the embodiments described with reference to the accompanying drawings without departing from the scope of the appended claims. Accordingly, various changes and modifications to the presently disclosed embodiments will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present subject matter and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.