CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application claims priority from Italian patent application no . 102020000021859 filed on 16/ 09/2020 , the entire disclosure of which is incorporated herein by reference .

TECHNICAL FIELD

The present invention relates to a machine for applying at least one cable to a pipeline , in particular in a body of water .

BACKGROUND ART

In the oil sector, a cable coupled to a pipeline , generally underwater, finds various applications .

In underwater oil fields , hydrocarbons are trans ferred from the field along metal pipes laid on the seabed and rising ("risers" ) towards a surface plant which has the function of managing production and processing the product so that it can be trans ferred at greater distances to a refinery, but also of unloading the product onto oil tankers or gas tankers .

In this context , a first application of the cable involves the trans fer of monitoring signals from sensors in order to monitor the dynamic behaviour, i . e . , the oscillations at various frequencies of the riser, generally induced by the motion of a floating plant ( FPSO) to which the riser is connected .

A second application involves the monitoring of the deformation of span pipe sections subj ect to vibrations induced by the current or by the transported fluid .

A third application involves the installation of heating power cables for heating underwater pipes or sections of underwater pipes .

According to the prior art , the cable is applied to the pipeline during the launching phase (piggy back cable ) on board a laying vessel and j ust before the pipeline is launched . The space available for carrying out these operations on board a laying ves sel is generally limited, sometimes the type of launch itsel f makes it di fficult to apply the cable around the pipeline before the laying ( the J-lay launching method) , and i f the operations are carried out by personnel , these operations involve risks . Moreover, when the launching operations comprise j oining individual sections of the pipeline , it is also necessary to j oin the individual sections of the cable , as happens for example in the J-lay launching method .

DISCLOSURE OF INVENTION One obj ect of the present invention is to provide a machine for applying at least one cable to a pipeline , which is free from the drawbacks of the prior art .

According to the present invention, a machine is provided for applying at least one cable to a pipel ine , the machine comprising :

- a frame extending along a longitudinal axis ;

- a gripping and moving device mounted on the frame and configured to couple the machine around the pipeline and move the machine along the pipeline in a travel direction parallel to the longitudinal axis ;

- a cable application equipment comprising a rotating open ring structure , which is configured to rotate with respect to the frame and around the pipeline when the machine is gripping the pipeline ; and an unwinding device for the controlled unwinding of a reel of cable ; said unwinding device being mounted on said rotating open ring structure ;

- a strapping apparatus mounted on the frame for applying straps around the cable and the pipe .

The present invention allows the cable to be applied to the pipeline in the body of water and in a completely automatic way .

In particular, the gripping and moving device comprises a plurality of gripping members , two of which articulated to the frame and movable between an open position to allow the insertion of the pipeline between the gripping members , and a closed position to tighten the pipeline between the gripping members .

This allows the machine to be coupled to the pipeline so that the machine is integral with the pipeline and runs in a determined travel direction with respect to the pipeline .

In particular, each gripping member is motori zed to move the machine along the pipeline , in particular each gripping member is a motori zed track .

This allows the travel of the machine along the pipeline to be controlled in a simple way .

In particular, the machine comprises a plural ity of unwinding devices for the controlled unwinding of respective cables from respective reels , the said unwinding devices being supported by the rotating open ring structure so as to rotate together with the rotating open ring structure .

In particular, the machine comprises at least one thrust module coupled to the frame so as to provide the machine with a given hydrostatic thrust to facilitate the installation of the machine on the pipeline .

In particular, the cable application equipment is mounted at the head of the frame and the strapping apparatus is mounted at the rear of the frame with respect to the direction of travel of the machine .

In this way, from the operational point of view, the cable application equipment winds the cable in a helical manner around the pipeline as the machine advances and the strapping apparatus applies a succession of straps around the pipeline and the cable wound around the pipeline during a machine stop .

In particular, the strapping apparatus comprises :

- a support element fixed to the frame ;

- a strap feeding device ;

- two arms movable with respect to the support element and configured to guide a strap around the pipeline and the cable ;

- a clamping device configured to hold an end portion of the strap ; an advancing device configured to advance and tighten the strap around the pipeline and the cable ;

- a j unction device configured to j oin two overlapping portions of the strap so as to close the strap around the pipeline and the cable ; and

- a cutting device configured to separate the strap upstream of the j oined portion . In this way, a strap can be guided and applied in the body of water around a selected zone of the pipeline in an inexpensive and reliable manner .

A further obj ect of the present invention is to provide a system for applying at least one cable to a pipeline in a body of water, which allows the drawbacks of the prior art to be overcome or at least mitigated .

According to the present invention, a system is thus provided for applying at least one cable to a pipeline , the system comprising :

- the machine for applying at least one cable to a pipeline as claimed in any one of the foregoing Claims ; and two clamps , each of which is configured to be mounted around the pipeline and comprises at least one connector configured to be connected to one end of the cable , so as to secure the two ends of the cable to the pipeline .

In particular, the system comprises an ROV for installing the machine on the pipeline , closing the said clamps around the pipeline , and optionally attending to the operation of said machine .

In this way, the ROV supports the cable application operations , optionally supplying the machine with electrical and/or hydraulic power, a control unit , and a system for communicating with the surface of the body of water .

A further obj ect of the present invention is to provide a method for applying at least one cable to a pipeline in a body of water, which allows the drawbacks of the prior art to be at least partly mitigated .

According to the present invention, a method is thus provided for applying at least one cable to a pipel ine in a body of water, the method comprising :

- coupling a frame of a machine to apply the at least one cable around the pipeline ;

- attaching one end of the cable of a reel supported by the machine to the outer surface of the pipeline ;

- moving the machine in a determined travel direction along the pipeline using the pipeline as a guide for the machine so as to unwind the cable from the reel ; rotating the reel with respect to the frame and around the pipeline as the machine advances so as to wind the cable in a helical manner around the pipeline ; and

- applying a succession of straps around the pipeline and the cable laid around the pipeline .

This method allows the cable to be applied to the pipeline in a completely automatic way by means of the cable application machine . A further obj ect of the present invention is to provide a computer program which mitigates the drawbacks of the prior art described herein .

In accordance with the present invention, a computer program is provided, which is configured to control a machine and can be directly loaded into a memory of the computer to carry out the steps of the method as described above , when the program is implemented by the computer .

The program allows the method to be implemented in a simple and economical way .

Furthermore , the present invention relates to a program product comprising a readable medium on which the program is stored .

BRIEF DESCRIPTION OF THE DRAWINGS

Further features and advantages of the present invention will be apparent from the following description of a non-limiting embodiment thereof , with reference to the Figures of the accompanying drawings , wherein :

- Figure 1 is a perspective view, with parts removed for clarity and schemati zed parts , of a system for applying at least one cable to a pipeline provided in accordance with the present invention;

- Figure 2 is a perspective view, with parts removed for clarity, of a machine for applying at least one cable of the system of Figure 1 ; - Figure 3 is a front view, with schemati zed parts and parts removed for clarity, of the machine of Figure 2 ;

- Figure 4 is a front view, with parts removed for clarity and parts on an enlarged scale , of a detai l of Figure 3 ;

Figure 5 is a side elevation view, with parts removed for clarity, of a strapping apparatus of the machine of Figure 2 ; and

- Figure 6 is a schematic view, with parts removed for clarity, of a control device of the system of Figure 1 .

BEST MODE FOR CARRYING OUT THE INVENTION

With reference to Figure 1 , reference numeral 1 indicates , as a whole , a system for applying at least one cable 2 - two cables 2 in the example shown herein - to a pipeline 3 in a body of water 4 . The system 1 comprises a machine 5 for applying the cable 2 ; two clamps 6 ( only one of which is shown in Figure 1 ) configured to be clamped around the pipeline 3 and provided with respective connectors 7 configured to be connected to one end of the cables 2 ; an ROV 8 ; and a control station 9 , which, in the non-limiting example of the present invention shown herein, is arranged on the surface of the body of water 4 .

The machine 5 i s configured to be coupled to the pipeline 3 ; move along the pipeline 3 using the pipeline 3 as a guide ; unwind the cables 2 from respective reels 10 along the pipeline 3 ; wind each cable 2 in a helical manner around the pipeline 3 ; and attach each cable 2 to the pipeline 3 .

The machine 5 comprises a plurality of thrust modules 11 which make the machine 5 particularly suitable for underwater use .

The ROV 8 is configured to install the machine 5 on the pipeline 3 , close the clamps 6 around the pipeline 3 , and optionally attend to the operation of the machine 5 .

In accordance with a variant of the present invention, not shown in the accompanying drawings , the ROV 8 is configured to transmit electrical and/or hydraulic power to the machine 5 and control the machine 5 .

With reference to Figure 2 , in which the thrust modules 11 have been removed, the machine 5 comprises a frame 12 extending along a longitudinal axis Al ; a gripping and moving device 13 mounted on the frame 12 and configured to couple the machine 5 around the pipeline 3 and move the machine 5 along the pipeline 3 ( Figure 1 ) in a travel direction DI parallel to the longitudinal axis Al ; a cable 2 application equipment 14 ; and a strapping apparatus 15 for applying straps 16 ( Figure 1 ) around the cables 2 and the pipeline 3 ( Figure 1 ) .

The frame 12 extends mainly along the longitudinal axis Al and supports , at its opposite ends along the longitudinal axis Al , the cable application equipment 14 and the strapping apparatus 15 in succession with reference to the travel direction DI .

The frame 12 also supports , between the cable application equipment 14 and the strapping apparatus 15 , a plurality of gripping members 17 configured to be arranged in contact with the pipeline 3 ( Figure 1 ) .

Two gripping members 17 are articulated to the frame 12 and selectively movable with respect to the frame 12 by means of actuators 18 in order to allow the gripping members 17 to move between an open position and a closed position . Four gripping members 17 are mounted integral with the frame 12 . This al lows the pipeline 3 to be clamped between the gripping members 17 and the machine 5 to be integral with the pipeline 3 ( Figure 1 ) .

At least one gripping member 17 is motori zed to ensure the movement of the machine 5 along the pipeline 3 ( Figure 1 ) . In the example shown herein, all the gripping members 17 are motori zed so as to prevent the machine 5 from being subj ected to unbalanced forces . In particular, each gripping member 17 comprises a carriage 19 and a track 20 such that the contact area between the gripping member 17 and the pipeline 3 can be extended .

The cable application equipment 14 comprises a rotating open ring structure 21 , which is configured to rotate with respect to the frame 12 around the pipeline 3 when the machine 5 is gripping the pipeline 3 ( Figure 1 ) ; and two unwinding devices 22 for the controlled unwinding of the respective cables 2 from the respective reels 10 .

The frame 12 includes an open ring structure 23 to house and guide the rotating open ring structure 21 .

With reference to Figures 3 and 4 , the open ring structure 23 comprises an open ring crown wheel 24 and supports two motors 25 and respective pinions 26 in mesh with the open ring crown wheel 24 . The open ring crown wheel 24 has an extension greater than 180 ° and the pinions 26 are arranged such that the open ring crown wheel 24 is always in mesh with at least one of the two pinions 26 .

With reference to Figure 2 , each unwinding device 22 is mounted on the rotating open ring structure 21 and comprises a support 27 for supporting a spool 28 on which a reel 10 of cable 2 is wound; and a pulley 29 , which has the function of returning the cable 2 in the vicinity of the pipeline 3 ( Figure 1 ) .

Each spool 28 is configured to rotate about a respective axis of rotation A2 , so as to unwind the respective cable 2 from the respective reel 10 . In particular, the rotation of each spool 28 about the respective axis of rotation A2 is braked by a respective braking device , not shown in the attached figures , so as to keep the respective cable 2 taut during the application of the cables 2 around the pipeline 3 ( Figure 1 ) .

In accordance with a variant of the present invention, each spool 28 is motori zed so as to control the rotation speed of each spool 28 about the respective axis of rotation A2 and keep the respective cable 2 taut .

With reference to Figure 5 , the strapping apparatus 15 comprises : a support element 30 fixed to the frame 12 ( Figure 2 ) ; a feeding device 31 for feeding a band 32 from which the straps 16 are cut ( Figure 1 ) ; two arms 33 selectively movable with respect to the frame 12 between an open position and a closed position by respective actuators 34 and configured to guide the band 32 around the pipeline 3 and the cables 2 ; a clamping device 35 configured to hold an end portion of the band 32 ; an advancing device 36 configured to advance and tighten the band 32 around the pipeline 3 and the cables 2 ; a j unction device 37 configured to j oin two overlapping portions of the band 32 so as to close the band 32 around the pipeline 3 and the cables 2 ; and a cutting device 38 configured to separate the band 32 from the j unction area .

With reference to Figure 6 , the system 1 comprises a control device 39 for controlling the machine 5 . The control device 39 comprises a control unit 40 , which can be arranged on board the machine 5 itsel f or on board the ROV 8 or in the control station 9 floating on the surface of the body of water 4 . The control device further comprises a sensor 41 configured to detect the position of the rotating open ring structure 21 with respect to the frame 12 ( Figure 2 ) ; at least one sensor 42 for detecting the position of the gripping members 17 ; a sensor 43 for detecting whether the arms 33 are in the closed position or in the open position; and a sensor 44 for detecting whether the band 32 has two overlapping portions downstream of the j unction device 37 .

The control unit 40 is configured to control the two motors 25 according to the position of the rotating open ring structure 21 detected by the sensor 41 and to control the gripping members 17 and the actuators 18 according to the position detected by the sensor 42 .

Moreover, the control unit 40 is configured to control the feeding device 31 , the actuators 34 of the two arms 33 , the clamping device 35 , the advancing device 36 , the j unction device 37 and the cutting device 38 according to the signals detected by the sensors 43 and 44 .

In addition, the control device 39 comprises a computer 45 , which comprises a memory containing a program for controlling the system 1 and i s configured to implement said program .

The computer 45 can be programmed directly or is configured to read program media through special interfaces .

In use and with reference to Figure 1 , the machine 5 is coupled around the pipeline 3 and clamped to the pipeline 3 by the closing of the gripping members 17 ( Figure 2 ) around the pipeline 3 .

The ROV 8 tightens the clamp 6 - not shown in the attached figures - to which the starting ends of the cables 2 are fastened, around the pipeline 3 .

At this point , with reference to Figure 2 , the machine 5 moves along the pipeline 3 by means of the tracks 20 of the gripping and moving device 13 and using the pipeline 3 as a guide .

At the same time , the motors 25 ( Figures 3 and 4 ) rotate the rotating open ring structure 21 around the pipeline 3 , and the two unwinding devices 22 unwind in a controlled manner the respective cables 2 from the respective reels 10 , so as to wind the cables 2 in a helical manner around the pipeline 3 as the machine 5 advances .

In greater detail , as each cable 2 unwinds from the respective reel 10 , the rotation o f each spool 28 about the respective axis of rotation A2 is braked by a braking device , not shown in the attached figures .

At regular or predetermined intervals , the movement of the machine 5 along the pipeline 3 is stopped so as to alternate between forward and stop phases , during which the strapping apparatus 15 applies a strap 16 ( Figure 1 ) around the pipeline 3 and the cables 2 .

With reference to Figure 5 , during this stop phase , the arms 33 are moved from the open position to the closed position, and the sensor 43 monitors the relative positions of the two arms 33 and supplies the relevant signal s to the control unit 40 .

When the arms 33 are in the closed position, the advancing device 36 feeds the band 32 inside the arms 33 .

The sensor 44 detects the presence of the band 32 inside the arms 33 in a given position and provides the relevant signals to the control unit 40 .

After receiving the consent from the sensor 44 , the control unit 40 actuates the clamping device 35 so as to hold the band 32 .

Next , the advancing device 36 tightens the band 32 around the pipeline 3 and the cables 2 , extracting the band 32 from the arms 33 . Once the band 32 is tightened around the pipeline 3 and the cables 2 , the j unction device 37 j oins the two overlapping portions of the band 32 , so as to close the band 32 around the pipeline 3 and the cables 2 . The sensor 44 monitors the outcome of the j oining operation and supplies relevant signals to the control unit 40 . Subsequently, the cutting device 38 separates the band 32 upstream of the j oined portion .

With reference to a non-limiting embodiment of the present invention, all the steps of the operations for applying the strap 16 ( Figure 1 ) around the pipeline 3 and the cables 2 are controlled by the control unit 40 .

With reference to Figure 1 , when the operations for applying the cables 2 around the pipeline 3 are completed, the ROV 8 tightens the clamp 6 , to which the terminal ends of the cables 2 are fastened, around the pipeline 3 .

At this point , the gripping members 17 are moved from the closed position to the open position so as to uncouple the machine 5 from the pipeline 3 .

In accordance with one embodiment , during the operations for applying the cables 2 around the pipeline 3 , the ROV 8 assists the machine 5 in said operations . In particular, the ROV 8 transmits electrical and/or hydraulic power to the machine 5 and also controls the machine 5 visually by means of a video camera not shown in the attached figures .

Lastly, it is clear that the present invention can be subj ect to variations with respect to the embodiment described above without however departing from the scope of the following claims .