CROSS-REFERENCE TO RELATED APPLICATIONS

This Patent Application claims priority from Italian Patent Application No . 102022000019623 fi led on September 23 , 2022 , the entire disclosure of which is incorporated herein by reference .

TECHNICAL FIELD

The present invention relates to a cooling system and method for dissipating heat from an annular portion of a pipeline .

In particular, the present invention relates to a cooling system and method for dissipating heat from a j oint portion comprised between two adj acent pipe sections of the pipeline during the installation operations of said pipeline , however without limiting the wide range of possible applications of the present invention .

BACKGROUND ART

As is known, in the oil & gas sector, pipelines for transporting hydrocarbons must be installed in an installation site , such as the bed of a body of water or on dry land . Typically, during the installation operations , a plurality of pipe sections of standard si ze are j oined to one another so as to form a continuous pipeline . In particular, said pipe sections have a standard length of 12 metres and are made of a metallic material .

Generally, the pipe sections are j oined to one another by welding and subsequently the welded j oint portions are covered with a heat-shrinkable sleeve applied using heat supplied, for example , by means of a flame or special lamps . In particular, the sleeve provides protection from corrosion and can thermally insulate the pipeline from the outside environment . The heat supplied to shrink the sleeve is generally characterised by a high power and intensity, also determining heating of the metallic material of the pipeline .

Due to its mass and its thermal inertia, the pipeline can remain hot at length . Moreover, within a given range of operating temperatures , the sleeve guarantees suitable mechanical performance and properties , while outside said operating range , the sleeve can deteriorate , for example as a result of the pressure exerted on the conveyor rollers of the production lines .

Consequently, the cooling times of the pipeline , required to guarantee the correct temperature of the sleeve , are typically long and hence incompatible with the fast pace of the installation operations of the pipeline .

In order to accelerate the installation operations of the pipeline , the inner surfaces o f the j oint portions of the pipeline must be cooled, without waiting for the sleeve to dissipate heat naturally . In particular, adequate cooling of the j oint portion of the pipeline prevents damage to the sleeve during laying, limiting the ri sk of deterioration of the protective and/or insulating characteristics of the sleeve .

Generally, the sleeves can be cooled internally and/or externally by delivering water onto the respective j oint portions . However, this prior art technique requires the provision of a water delivery system of complex implementation distributed along the whole of the production line of the pipeline for collection and recirculation of the cooling water .

A further prior art technique consists in cooling each sleeve internally by means of a cooling device disposed within the pipeline and conf igured to exchange heat through conduction with each j oint portion during installation of the pipeline .

By way of example , the document US 2015/ 0273636 describes a cooling device comprising a motori zed cart and a cooling section, which is guided by the motori zed cart within the pipeline and is provided with a plurality of movable cooling fins . In particular, the cooling section comprises a central support element and an actuating mechanism configured to radially expand/retract each cooling fin from the central support element . Each cooling f in comprises a rigid hollow element to allow a cooling fluid to flow inside it so as to dissipate heat from the j oint portion of the pipeline when it contacts said j oint portion .

However, pipelines have geometric imprecisions in their actual construction, such as out of roundness of the circumferential profile of the pipeline or stepping due to welds , which compromise the theoretical cylindrical shape . Said imprecisions are various and are characteristics of the manufacturing process and hence of the site of origin of the pipeline . In particular, said imprecisions cause non-optimal adhesion of the cooling fins on the j oint portion to be cooled, considerably limiting the ef ficiency of the cooling process and lengthening its times . In other words , heat exchange through contact between the j oint portion and the cooling fins is highly inef ficient .

Moreover, the actuating mechanism of the cooling fins is heavy and bulky and, consequently, increases the weights , volumes and, in general , the complexity of the cooling device .

SUBJECT MATTER OF THE INVENTION

An obj ect of the present invention is to produce a cooling system for dissipating heat from an annular portion of a pipeline that overcomes the problems of the prior art .

In particular, an obj ect of the present invention i s to produce a cooling system that increases the ef ficiency of the cooling process of an annular portion of a pipeline and that , at the same time , is simple to set up and use . In accordance with the present invention there is produced a cooling system for dissipating heat from an annular portion of a pipeline , preferably from a j oint portion comprised between two adj acent pipe sections of the pipeline , the cooling system comprising :

- at least one motori zed cart configured to advance within the pipeline ; and

- a cooling device , which is carried by the cart and comprises an expandable tank, configured to contain a cooling fluid under pressure and to expand as the pressure of the cooling fluid within it increases so as to contact an inner surface of the annular portion of the pipeline .

Due to the present invention, it i s possible to guarantee optimal adhesion between the cooling tank and the inner surface of the pipeline to be cooled . In this way, it is possible to ef fectively and rapidly cool the annular portion of the pipeline . Moreover, the fact that the cooling fluid is contained within the expandable tank eliminates the need to recover the cooling fluid within the pipel ine in order to dispose of or recirculate the cooling fluid and allows mechanical cooling members to be eliminated, reducing the footprint of the machine .

In practice , the cooling fluid performs the dual function of expanding the expandable tank and of determining forced cooling of the annular portion of the pipeline .

In particular, the expandable tank comprises at least one inlet opening for the cooling fluid and at least one outlet opening for the cooling fluid so as to allow the recirculation of the cooling fluid within the expandable tank .

In this way, it is possible to further increase the heat exchange ef ficacy between the annular portion and the cooling fluid . In practice , the heat exchange between the annular portion of the pipeline and the cooling device takes place both by conduction, which is determined by the contact between the expandable tank and the inner surface of the annular portion of the pipeline , and by forced convection, which is promoted by the circulation of the cooling fluid within the expandable tank .

In particular, the expandable tank can consist o f an elastic membrane , so as to adapt the shape of the expandable tank to the annular portion to be cooled and follow any irregularities thereof .

In more detail , the elastic membrane is made of a polymeric material ; preferably the elastic membrane being made of glass fibre and polytetrafluoroethylene ( PTFE ) or of a silicone material .

In practice , the elastic membrane is characterised by di f ferent properties , such as thermal resistance , thermal conductivity and mechanical resistance , which allow optimal performance to be obtained, for example in terms of heat exchange , duration and flexibility in di f ferent operating situations .

In this way, it i s possible to provide the elastic membrane with an adequate mechanical resistance to support the internal pressure of the cooling fluid and at the same time promote cooling of the annular portion of the pipeline .

In particular, the expandable tank is substantially annular in shape and extends around a longitudinal axis .

In practice , the expandable tank extends in a ring so as to follow the inner surface of the annular portion of the pipeline to be cooled, in this way limiting the volume of the tank .

In particular, the expandable tank can be divided into a plurality of annular sectors , each of which comprises at least one respective inlet opening for the cooling fluid and at least one respective outlet opening for the cooling fluid so as to allow the recirculation of the cooling fluid within each annular sector .

In this way, it is possible to control the temperature and the pressure of the cooling fluid in each annular sector independently to optimise the cooling process of the annular portion of the pipeline .

In particular, the cooling system comprises a supply circuit configured to supply the cooling fluid to the expandable tank .

In this way, it is possible to control the pressure within the expandable tank and allow the recirculation of the supply fluid .

In particular, the supply circuit comprises a supply valve configured to adj ust a supply flow of the cooling fluid to the expandable tank, and a return valve configured to adj ust an outlet flow of the cooling fluid from the expandable tank .

By separately controlling the supply valve and the return valve , it is possible to adj ust with precision the pres sure and the flow of the cooling fluid within the expandable tank .

In particular, the supply circuit comprises a supply pump configured to be disposed outside the pipeline .

In this way, it is possible to reduce the footprints of the portions of the cooling system to be disposed within the pipeline .

In particular, the supply circuit comprises an external tank, which is disposed outside the pipeline and is configured to contain the cooling fluid; and a heat exchanger, which is disposed outside the pipeline and is configured to cool the cooling fluid .

In this way, it is possible to limit weights and dimensions of the cooling device and hence increase its performance .

A further obj ect of the present invention is to provide a cooling method for dissipating heat from an annular portion of a pipeline that overcomes the problems of the prior art .

In accordance with the present invention, there is provided a cooling method for dissipating heat from an annular portion of a pipeline , preferably from a j oint portion comprised between two adj acent pipe sections o f the pipeline , the method comprising the steps of :

- advancing a cooling device within the pipeline ;

- containing a cooling fluid under pressure within an expandable tank of the cooling device ; and increasing the pressure of the cooling fluid within the expandable tank to expand the expandable tank so that the expandable tank contacts an inner surface of the annular portion of the pipeline .

Due to the present method, it is possible to increase the ef ficiency of the cooling process of the annular portion of the pipeline .

BRIEF DESCRIPTION OF THE DRAWINGS

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

- Fig . 1 is a side elevation view, with parts schemati zed and parts removed for clarity, o f a cooling system produced in accordance with the present invention;

- Fig . 2 is a sectional view, with parts schemati zed and parts removed for clarity, of the cooling system of Fig . 1 ; - Fig . 3 is a perspective view of an expandable tank of the cooling system of Fig . 1 ; and

- Fig . 4 is a perspective view of a further embodiment of the expandable tank of the cooling system of Fig . 1 .

DETAILED DESCRIPTION OF THE DRAWINGS

With reference to Figs . 1 and 2 , the number 1 indicates as a whole a cooling system for dissipating heat from an annular portion 2 of a pipeline 3 . In particular, the pipeline 3 extends along a longitudinal axis Al , comprises a plurality of pipe sections 4 j oined to one another, and has an inner surface 5 and an outer surface 6 . In more detail , the annular portion 2 comprises a j oint portion 7 compri sed between two adj acent pipe sections 4 .

In accordance with a non-limiting embodiment of the present invention, the cooling system 1 is configured to dissipate heat from the j oint portion 7 during the installation operations of the pipeline 3 .

It is understood that , in accordance with further embodiments of the present invention, not shown in the accompanying figures , the cooling system 1 can be used for dissipating heat from any further portion of the pipeline 3 .

In particular, the cooling system 1 is used in a prefabrication area of a plant for producing and laying the pipeline 3 .

In accordance with an embodiment , the cooling system 1 can be used in all high production work areas for welding and handling pipelines , for example in the prefabrication areas of pipe sections with a length greater than 12 metres . Prefabrication can be carried out in a site on dry land or on board a laying vessel .

In the case described and illustrated herein, each pipe section 4 is made of a metallic material and is welded to a further adj acent pipe section 4 along the respective j oint portion 7 .

In particular, each pipe section 4 has a length measured along the longitudinal axis Al of around 12 metres .

In accordance with an embodiment , the j oint portion 7 is covered by a sleeve 8 , preferably heat-shrinkable and applied to the j oint portion 7 using heat . In particular, the sleeve 8 is made of an anti-corrosion and/or thermally insulating material .

The cooling system 1 comprises a motori zed cart 9 configured to advance along the longitudinal axis Al within the pipeline 3 ; and a cooling device 10 , which is carried by the cart 9 and comprises an expandable tank 11 , configured to contain a cooling fluid under pressure and to expand as the pressure of the cooling fluid within it increases so as to contact the inner surface 5 of the annular portion 2 of the pipeline 3 .

In accordance with a non-limiting embodiment of the present invention, the cooling fluid is a liquid, for example water .

In accordance with an alternative embodiment, the cooling fluid is a gas , for example air .

Moreover, the cooling system 1 comprises a supply circuit 12 configured to supply the cooling fluid to the expandable tank 11 .

In particular, the supply circuit 12 comprises a supply valve 13 configured to adj ust a supply flow of the cooling fluid to the expandable tank 11 , and a return valve 14 configured to adj ust an outlet flow of the cooling fluid from the expandable tank 11 .

In more detail , the supply valve 13 comprises a plug 15 movable between an open position, in which the supply flow of the cooling fluid is delivered to the expandable tank 11 , and a closed position, in which the supply f low of the cool ing fluid is interrupted . The return valve 14 comprises a plug 16 movable between an open position, in which the outlet flow of the cooling fluid is delivered from the expandable tank 11 , and a closed position, in which the outlet f low of the cool ing fluid is interrupted .

In particular, the supply circuit 12 comprises a supply pump 17 configured to be disposed outside the pipeline 3 and a plurality of supply conduits 18 , each of which connects fluidically the supply pump 17 to the expandable tank 11 so as to allow the circulation of the cooling fluid in the expandable tank 11 and in the supply circuit 12 .

Moreover, the supply circuit 12 comprises an external tank 19 , which is disposed outside the pipeline 3 and is configured to contain the cool ing fluid; and a heat exchanger 20 , which is disposed outside the pipeline 3 and is configured to cool the cooling fluid .

In the non-limiting case of the present invention described and illustrated herein, the supply circuit 12 comprises a cooling circuit 21 , which is provided with the heat exchanger 20 and with a pump 22 configured to supply the cooling fluid to the cooling circuit 21 .

In particular, the external tank 19 comprises a chamber 23 configured to contain the cooling fluid at a first temperature , and a chamber 24 configured to contain the cooling fluid at a second temperature lower than the first temperature .

In more detail , the chamber 23 i s connected fluidically to an outlet of the expandable tank 11 and to an inlet of the cooling circuit 21 . The chamber 24 is connected fluidically to an inlet of the expandable tank 11 and to an outlet of the cooling circuit

21 .

In accordance with a non-limiting embodiment of the present invention, the supply valve 13 , the return valve 14 , the supply pump 17 and the cooling circuit 21 are configured to be disposed outside the pipeline 3 .

In the case described and illustrated herein, the cooling system 1 comprises two lateral carts 9 aligned along a longitudinal axis A2 , and a central body 25 , which is connected to the two carts 9 and is disposed between the two carts 9 . In particular, the central body 25 is cylindrical in shape and houses externally the expandable tank 11 .

Moreover, the cooling system 1 comprises a sensor assembly 26 , which is coupled to the cooling device 10 or to at least one of the carts 9 and is configured to detect the position of the cooling device 10 within the pipeline 3 and to emit a position signal indicative of said detected position . In particular, the sensor assembly 26 is configured to detect the relative position between the cool ing device 10 and the j oint portion 7 . In more detail , the sensor assembly 26 comprises an optical sensor, for example a video camera or camera or a laser sensor .

The cooling system 1 further comprises a control unit 27 configured to receive the position signal emitted by the sensor assembly 26 and to control the advancement of the carts 9 along the pipeline 3 as a function of said position signal so as to position the cooling device 10 at said j oint portion 7 .

In accordance with an embodiment , the control unit 27 is configured to send the position signal to a remote control site and to receive control signals from said remote control site . In this way, it is possible to remotely control the position of the cooling device 10 within the pipeline 3 . With reference to Fig . 3 , the expandable tank 11 is substantially annular in shape and extends around the longitudinal axis A2 .

The expandable tank 11 comprises two inlet openings 28 for the cooling fluid and two outlet openings 29 for the cooling fluid so as to allow the recirculation of the cooling fluid within the expandable tank 11 .

In particular, each inlet opening 28 is provided with a connector 30 for the connection with the respective supply conduit 18 , and each outlet opening 29 is provided with a connector 31 for the connection with the respective supply conduit 18 .

In particular, the expandable tank 11 extends along the longitudinal axis A2 for a length comprised between 500 millimetres and 700 millimetres . Preferably, said length is of around 600 millimetres .

In accordance with an embodiment , the expandable tank 11 is delimited by an elastic membrane 32 made of a polymeric material .

In particular, the elastic membrane 32 is made of glass fibre and polytetrafluoroethylene ( PTFE ) . Preferably, the elastic membrane 32 is made of two layers of glass fibre fabric coated with polytetrafluoroethylene ( PTFE ) .

In particular, the elastic membrane 32 has a thickness comprised between 1 millimetre and 3 millimetres . In more detail , each layer of glass fibre fabric has a thickness of less than 1 millimetre . Preferably, said thickness is comprised between 0 . 1 millimetre and 0 . 5 millimetres .

In accordance with an alternative embodiment , the elastic membrane 32 is made of a silicone material . With reference to Fig . 4 , a further embodiment of the present invention is shown, wherein the expandable tank 11 is divided into a plurality of annular sectors 33 .

In the case described and illustrated herein, each annular sector 33 comprises two inlet openings 28 provided with respective connectors 30 , and two outlet openings 29 provided with respective connectors 31 so as to allow the recirculation of the cooling fluid within each annular sector 33 .

In use and with reference to Figs . 1 and 2 , after the adj acent pipe sections 4 have been welded at the j oint portion 7 , the sleeve 8 is applied to the j oint portion 7 using heat .

Subsequently, the carts 9 advance the cooling device 10 along the pipeline 3 towards the j oint portion 7 . In particular, during said advancement , the sensor assembly 26 detects the position of the cooling device 10 within the pipeline 3 and emits the position signal . The control unit 27 receives the position signal from the sensor assembly 26 and controls the advancement of the carts 9 along the pipeline 3 as a function of said position signal so as to position the cooling device 10 at said j oint portion 7 .

Once the cooling device 10 is positioned in the correct position, the supply pump 17 supplies the cooling fluid to the expandable tank 11 through the supply circuit 12 . The supply valve 13 and the return valve 14 control the flow of the cooling fluid through the supply circuit 12 and through the expandable tank 11 .

In particular, the supply valve 13 and the return valve 14 are controlled so as to adj ust the pressure of the cooling fluid within the expandable tank 11 . By way of example , by opening the supply valve 13 and maintaining the return valve 14 closed, the pressure within the expandable tank 11 is increased . The increase of the pressure of the cooling fluid within the expandable tank 11 determines an expansion of the elastic membrane 32 , which contacts the inner surface 5 of the j oint portion 7 .

The cooling of the j oint portion 7 is determined by heat exchange by conduction due to the contact between the elastic membrane 32 and the inner surface 5 of the j oint portion 7 and by heat exchange by convection due to the circulation of the cool ing fluid within the expandable tank 11 .

It is evident that variations can be made to the present invention without however departing from the scope of protection of the appended claims .