VALVE

Abstract

A valve arrangement for a hose end coupler of a transfer hose for the offloading of hydrocarbons from an offshore floating production storage and offloading vessel (FPSO) to a shuttle tanker is described. The valve arrangement comprises a linear valve comprising a linear valve actuator movable between a first position whereat the valve is closed and a second position whereat the valve is open; a secondary valve comprising a secondary valve actuator movable between a first position whereat the valve is closed and a second position whereat the valve is open; wherein the linear valve actuator and the secondary valve actuator are operatively coupled such that movement of the linear valve actuator between the first position and the second position effects a corresponding movement of the secondary valve actuator between the first position and the second position. A hose end coupler with such a valve arrangement, and a transfer hose and transfer system and method incorporating such a hose end coupler with such a valve arrangement are also described.

Claims

1. A valve arrangement for a hose end coupler of a transfer hose for the offloading of hydrocarbons from an offshore floating production storage and offloading vessel (FPSO) to a shuttle tanker comprising: a linear valve comprising a linear valve actuator movable between a first position whereat the valve is closed and a second position whereat the valve is open; a secondary valve comprising a secondary valve actuator movable between a first position whereat the valve is closed and a second position whereat the valve is open; wherein the linear valve actuator and the secondary valve actuator are operatively coupled such that movement of the linear valve actuator between the first position and the second position effects a corresponding movement of the secondary valve actuator between the first position and the second position.

2. The valve arrangement in accordance with claim 1 wherein the secondary valve comprises a rotating valve having a secondary rotating valve actuator carried within a valve housing that is mounted to be rotatable between a first position whereat the valve is closed and a second position whereat the valve is open.

3. The valve arrangement in accordance with claim 2 wherein the secondary rotating valve actuator is mounted to be rotatable between the first position whereat the secondary valve actuator is in sealing engagement with a portion of a valve housing and the second position whereat the valve is not in sealing engagement with a portion of the valve housing.

4. The valve arrangement in accordance with claim 2 wherein the linear valve actuator and the secondary valve actuator are operatively coupled such that linear movement of the linear valve actuator causes rotation of the secondary rotating valve actuator.

5. The valve arrangement in accordance with claim 2 wherein the secondary valve comprises a rotating butterfly valve.

6. The valve arrangement in accordance with claim 5 wherein the secondary valve comprises a rotating valve in which the valve actuator comprises a disc carried within a valve housing and mounted to rotate between a first position whereat an edge portion of the disc is in sealing engagement with a portion of a valve housing and a second position whereat the edge portion of the disc is not in sealing engagement with a portion of the valve housing.

7. The valve arrangement in accordance with claim 1 combined with a coupling arrangement to comprise a hose end coupler, wherein the linear valve is adapted to be actuated to the open position by a coupling mechanism on a shuttle tanker when the hose end coupler is coupled to such a coupling mechanism in use.

8. The valve arrangement in accordance with claim 1 mounted into a product transfer hose end such that the linear valve actuator is translatable in a hose axial direction.

9. The valve arrangement in accordance with claim 1 wherein the linear valve actuator is contained within a valve housing and mounted to be translatable between a first position whereat the linear valve actuator is in a face to face sealing engagement with a portion of the valve housing and a second position whereat the linear valve actuator is not in a face to face sealing engagement with the said portion of the valve housing.

10. The valve arrangement in accordance with claim 9 wherein a distal portion of the linear valve actuator and an engagement portion of the valve housing are adapted to provide mutually engageable sealing surfaces when the linear valve actuator is in the first position.

11. The valve arrangement in accordance with claim 9 wherein the linear valve actuator comprises a linearly translatable piston formation carried by and translatable relative to a holding formation so as to be movable between the first position and the second position.

12. The valve arrangement in accordance with claim 11 wherein the piston formation is biased to return the first position.

13. The valve arrangement in accordance with claim 12 wherein the piston formation is spring biased to return the first position.

14. The valve arrangement in accordance with claim 12 or claim 13 wherein the bias is damped by provision of a hydraulic or pneumatic damper.

15. The valve arrangement in accordance with claim 1 wherein the linear valve and the secondary valve are operatively coupled by an actuating connection such that movement of the linear valve actuator between the first position and the second position causes via the actuating connection a corresponding movement of the secondary valve actuator between the first position and the second position.

16. The valve arrangement in accordance with claim 15 wherein the actuating connection comprises a direct physical link between the linear valve actuator and the secondary valve actuator.

17. The valve arrangement in accordance with claim 16 wherein the direct physical link comprises a mechanical link and/or a hydraulic link.

18. The valve arrangement in accordance with claim 17 wherein the linear valve actuator is a rotating valve having a rotating valve actuator comprising a disc actuator and the linear valve actuator is a translatable actuator and a direct mechanical link is provided between the linear valve actuator and the disc actuator such that translation of the linear valve actuator acts directly to cause rotation of the disc actuator.

19. The valve arrangement in accordance with claim 1 disposed as a hose end valve in a transfer hose for use in the offloading of hydrocarbons from an offshore floating production storage and offloading vessel (FPSO) to a shuttle tanker.

20. A product transfer hose for the offloading of hydrocarbons from an offshore floating production storage and offloading vessel (FPSO) to a shuttle tanker comprising an elongate hose defining a conduit for the passage of hydrocarbons between a first end and a second end and having at one of the said ends a valve arrangement in accordance with claim 1.

21. The product transfer hose in accordance with claim 20 wherein the valve arrangement is provided at the said one end of the elongate hose arranged such that the linear valve is positioned at the hose outlet and the secondary valve is positioned behind the linear valve, spaced away from the hose outlet.

22. The product transfer hose in accordance with one of claim 20 wherein the said one of the ends of the transfer hose includes a coupling formation that is adapted to engage with a complementary coupling arrangement on an off shore shuttle tanker, with the valve arrangement carried in the said end of the transfer hose being configured such that the action of effecting such a coupling causes the linear and secondary valves to move from the closed to the open position.

23. The product transfer hose in accordance with claim 20 supplied in combination with an offshore floating production storage and offloading vessel (FPSO) having a fluid reservoir, the said other of the said ends being in fluid communication with the fluid reservoir.

24. An off-loading system for the off-loading of hydrocarbons from an offshore floating production storage and offloading vessel (FPSO) to a shuttle tanker comprising: an FPSO, a shuttle tanker, and a transfer hose fluidly coupled to the FPSO and selectively fluidly coupleable to the shuttle tanker, said transfer hose comprising a transfer hose in accordance with claim 20.

25. A method for the off-loading of hydrocarbons from an offshore floating production storage and offloading vessel (FPSO) to a shuttle tanker comprising: providing a hose defining a conduit for the passage of hydrocarbons between a first end and a second end and having at one of the said ends a valve arrangement; fluidly connecting the other end of the hose to an FPSO so as to be in fluid communication with a fluid reservoir therein; coupling the first end of the hose to a shuttle tanker and thereby causing the valve arrangement to open, and to effect a fluid connection between a fluid storage on the shuttle tanker and the fluid storage on the FPSO; transferring fluid from the fluid storage on the FPSO to the fluid storage on the shuttle tanker.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0067] FIG. 1 shows a simple prior art hose end coupler linear valve of the design commonly called a North Sea Type Hose End Valve or Offloading Hose Termination Piece;

[0068] FIGS. 2 to 4 illustrate an embodiment of the dual valve system of the invention as it is progressively opened;

[0069] FIG. 5 shows the embodiment in cross-section;

[0070] FIG. 6 shows a system deployed for offloading from an FPSO to a shuttle tanker.

DETAILED DESCRIPTION

[0071] FIG. 1 has been discussed above in the context of the prior art.

[0072] Nevertheless, since it is a particular advantageous feature of the dual valve arrangement of the present invention that the linear valve part of the dual valve is fully compatible with existing off-loading platforms and standards, it is consequently advantageous for the linear valve of the dual valve of the invention to be of conventional design, and the valve of FIG. 1 is therefore additionally illustrative of features of the linear valve part of the embodiment of the present invention.

[0073] FIG. 1 shows the valve in a closed configuration on the left hand side and in an open configuration on the right hand side. As is familiar the valve is typically used to effect a connection during a transfer operation between a transfer hose extending from and fluidly in communication with an offshore floating production storage and offloading vessel (FPSO) and a suitable inlet to a shuttle tanker. In each case as illustrated, the valve is shown with a shuttle tanker side on the right hand side and a transfer hose/FPSO side on the left hand side of the drawings. In each case, a connection would be made to a shuttle tanker during a transfer operation via the flange on the right hand, tanker connection, side in the drawings, and a transfer hose would extend to the FPSO from the left hand side of the drawings.

[0074] In use, as the transfer valve with the hose end coupler illustrated in FIG. 1 is brought across to and coupled to the bow loading system of a shuttle tanker, a coupling mechanism on the shuttle tanker will engage with the flange 3 on the valve housing, causing actuation means within the coupling arrangement on the shuttle tanker to bear upon a piston-type linear actuator 4 within the valve, and cause it to move in the direction of the arrows to cause the valve to open. In this configuration, crude oil may be offloaded from the storage tanks in the FPSO via the transfer hose and through the valve into suitable storage volumes within the shuttle tanker in conventional manner.

[0075] The piston-type actuation member of the linear valve in FIG. 1 is biased closed by the spring 5, with the biasing force modified by an axially mounted hydraulic damper. The net effect of this arrangement is that once the coupling is removed, the valve closes in a controlled manner, with the piston-type actuator moving to the closed configuration shown in the left hand side of FIG. 1. A suitable sealing engagement is thereby made between a forward sealing surface of the piston formation and a complementary surface of the valve housing. One or both surfaces may be provided with a sealing element.

[0076] The enlarged detail shows the sealing engagement being effected in the particular example of FIG. 1 between an o-ring seal 1 inset into a forward outer edge of the piston formation and a complementary surface 2 of the valve housing. Other designs of sealing element may be appropriate.

[0077] The modification of this principle to arrive at a dual valve embodiment of the first aspect of the invention, and its mode of operation, is shown schematically by the open frame perspective views of FIGS. 2 to 4.

[0078] A linear primary valve 6, which may be of suitable form to be compatible with existing systems, and is for example of the type illustrated in FIG. 1, is provided in conjunction with and operatively coupled to a secondary rotating valve 7. The rotating valve is a butterfly valve with a butterfly disc actuation formation 8. The arrangement is shown FIGS. 2 to 4 respectively and successively in a closed, partly open and fully open configuration.

[0079] The linear primary valve 6 is operated in conventional manner as above as a transfer hose incorporating the dual valve arrangement as an end valve is deployed for coupling, and the flange portion is engaged upon and coupled to a bow loading system of a shuttle tanker. The embodiment of the invention is distinctly characterised however by the provision of the secondary rotating valve, and of a direct operational coupling between the two valves, which in the particular example embodiment is offered by the mechanical arm 9 that provides a direct functional mechanical link between a rearward face of the translatable piston formation 10 of the primary valve 6 and an off-centre mounting on the rotatable disc actuator 8 of the secondary valve 7.

[0080] The effect of this during use, as illustrated in FIGS. 2 to 4, is that linear translation of the primary valve in an axial direction under the action of the coupling mechanism of the shuttle tanker is mechanically coupled to cause rotation of the disc actuator 8 out of its closed position and into open position.

[0081] The valve actuators are operatively coupled, such that the action of opening the primary valve opens the secondary valve, and the closure of the primary valve also effects closure of the secondary valve. Thus, the action of coupling to the bow loading system opens the primary valve and consequently the secondary valve and the act of decoupling causes the primary valve to close and consequently closes the secondary valve.

[0082] A particular advantage in accordance with the embodiment illustrated of the use of a secondary valve based on a butterfly principle with a disc actuator 8 is that the different functions of the two valves may produce different and potentially complementary effects, in particular in that their different sealing arrangements may advantageously give a synergistic degree of functionality. This is illustrated in the cross section in FIG. 5 showing the linear reciprocation in an axial direction of the translatable piston formation 10 relative to its sealing faces 12, and the rotational motion of the disk formation 8 relative to its sealing faces 11. The latter may produce a sweeping action which can be particularly effective at clearing debris from the valve, mitigating the risk of fouling and leakage, especially in an emergency shutdown situation.

[0083] An example of the deployment of the invention in use is shown in FIG. 6. The figure shows a simplified FPSO 18 and offloading shuttle tanker 20, where the tanker 20 is moored to the FPSO 18 via a hawser 14, and the hose string 16 provides a fluid connection between the FPSO 18 and the tanker 20 allowing, for example, crude oil to be transferred from the FPSO to the tanker. A dual valve in accordance with the principles of the invention is provided at the distal end of the hose string 16 where it is coupled to the Bow Loading System or BLS of the tanker and is actuated in the manner illustrated in FIGS. 2 to 4 by the action of such a coupling.