Patent Description:
The present invention further concerns to a method for coupling an offshore floating structure to a pre-laid mooring system by using a quick connector.

Conventionally, floating offshore platforms, and in particular, floating wind turbine platforms are linked to the seabed by means of a plurality of mooring lines which limit the displacement and rotation of the structure. That is to provide station-keeping, required for the wind turbine to operate and maintain position. Also, conventionally, floating platforms with the wind turbines are transported to the installation site completely assembled, towed by tugboats. However, installation and tensioning of mooring lines requires the use of multiple vessels and can be complicated to execute, requiring the use of specialized teams, vessels, and good weather conditions. It is expected that floating wind turbine platforms may need to be towed to port multiple times during their <NUM> - <NUM>-year lifetime to conduct maintenance on the turbine or the platform itself. Hence, it is highly desirable to have a means for safely and quickly disconnect and reconnect the platform.

The present invention therefore seeks to provide an apparatus for the connection and disconnection of the offshore floating platform to a pre-laid mooring system that makes this operation fast, easy, and not requiring complex planning such as multiple specialized vessels.

Document <CIT> describes an offshore structure consisting of a frame and multiple wind turbines, installed on a floating platform connected to a vertical axis in a way that allows weathervaning of the structure. The axis is kept stationary by means of an anchoring system. Its connection with the frame of the rotatable structure is designed to support it in multiple planes, keeping the wind turbines upright and steady.

In some other designs the floating structure is rotatable around a single mooring point, as it is described in the case of document <CIT> system. This invention further comprises means to disconnect the floating platform from a permanently moored structure by moving the lower and upper body with respect to each other using a semi-submersible barge. Furthermore, centring means consisting of a cone and a counter-cone pair guide the connection-disconnection manoeuvre.

In the last decades, many quick connectors were developed in the oil and gas offshore extraction industry to facilitate connection and disconnection of a vessel from a semi-submerged buoy. The buoy is conventionally anchored to the seabed, features a plurality of risers and drilling equipment, and is capable of withstanding sea waves and currents acting on the vessel so it can be kept in place even without a dynamic positioning system. The quick connector is usually located in the vessel below any kind of yaw system which allows the free rotation of the vessel around the buoy, allowing the alignment of the vessel to the direction of the wind.

Document <CIT> document discloses a disconnectable mooring system for production vessels. It includes a turret having a yaw system with a top bearing and a bottom bearing, and a quick connector progressing below the ship so it can weathervane and align to the wind, currents, or wave directions, and be driven to the harbour when fierce storms occur, or ice floes are present. The quick connector consists of a plurality of bear locks which are forced to interfere in an annular cavity machined on the buoy top interface by means of a collet driven by hydraulic cylinders.

Similarly, Document <CIT> patent describes a disconnectable mooring system that features a receiving member rotatably connected to the floating structure. The structural connection between the mooring buoy and the receiving member is made using a ring-shaped actuation member that engages circumferentially arranged latching members. Centring means used only allow the receiving member and mooring buoy to connect in a certain rotational position.

Document <CIT> describes a mooring method that allows a vessel to weathervane about a submerged buoy. The bearing assembly of the buoy has an inner hub coupled to an outer ring fixed to the buoy. The structural connector attached to the vessel is arranged to be releasably connectable to the inner hub. The connector comprises a plurality of collet segments which engage the inner hub to dog it securely to the connector. The radial load involved in the process of receiving the inner hub is transmitted between the vessel and the buoy through a radial bushing seat defined by the perimeter of a circular recess formed in the buoy.

Document <CIT> relates to a method of mounting wind turbines, wave machines and tidal stream turbines offshore, using mechanical guiding which only requires self-propelled barges. The method comprises the use of a socket and an intermediate supporting part which provide an internal guiding surface for the conically shaped end part of a structure being installed. The structure is initially held in the reclined position by clamps attached to a barge. Then, the end part of the structure is led into the mounting socket using the guiding wire, lowered by adjusting removable alignment means until the geometrical alignment of the mounting surfaces is achieved, and released out of the clamps. Grout injection is used afterwards to secure the mounting.

Document <CIT> discloses a connector used to connect pressure vessels that features toroidal members sliding parallel to motion of locking segments. One of the toroidal members, an actuating torus, engages an inner piston, moving it down and thus rocking a plurality of circumferentially arranged locking segments onto the hubs on the surface of the pressure vessel.

Document <CIT> discloses a quick connector coupling a floating offshore wind turbine to a pre-laid mooring system and comprising a base structure coupled to an upper body of the offshore floating structure; a mooring interface attached to a lower body of the pre-laid mooring system; and locking mechanism fluid-dynamically actuated to couple and decouple the base structure from the mooring interface.

The present invention comprises a quick connector configured to couple an upper body of an offshore floating structure to a lower body of a pre-laid mooring system. In some embodiments, the offshore floating structure may be a weathervaning floating offshore wind turbine (FOWT) platform, for example, and the pre-laid mooring system may be a Tension Leg Platform (TLP) type, for example, but the device could find use in other type of floating systems. The offshore floating structure and the pre-laid mooring system may be arranged aligned along a longitudinal axis. The quick connector may be configured to couple (preferably, coaxially couple) the offshore floating structure to the pre-laid mooring structure along the longitudinal axis. The longitudinal axis may be a geometrical longitudinal axis, not corresponding to a physical part of the quick connector.

The quick connector comprises a base structure configured to be coupled to an upper body of an offshore floating structure, a mooring interface configured to be attached to a lower body of a pre-laid mooring system, and a locking mechanism fluid-dynamically (hydraulically or pneumatically) actuated configured to couple and decouple the base structure from the mooring interface.

Preferably, the mooring interface is shaped as an outer female member designed to receive the base structure of the quick connector as an inner male member and matches it geometrically. However, the technical solution provided by the invention may also be applicable for configurations in which the mooring interface is configured as an inner male member and the base structure is configured as an outer male member. The base structure of the quick connector may be attached to a floating upper body of a FOWT platform or other type of offshore platform with the aim of securing it to the mooring system. The base structure and the mooring interface are configured to be connected (e.g., coaxially connected) to each other along a longitudinal axis. In preferred embodiments, the longitudinal axis, in an operative position, is configured as a vertical axis.

Once the base structure of the quick connector is guided until connection with the mooring interface is achieved, a plurality of peripherally or perimetrically (e.g., circumferentially) arranged locking claws (i.e., the locking claws may be arranged at a radial distance from the longitudinal axis) embedded into the base structure are aligned with a grooved surface of a ring-shaped portion of the mooring interface. In preferred embodiments, the grooved surface may be configured as an inner grooved surface of the ring-shaped portion of the mooring interface (e.g., the grooved surface may be configured as an inner surface of the ring-shaped portion).

Multiple hydraulic or pneumatic pistons may be mounted on the base structure and operatively connected to move the locking claws between a release position in which the locking claws are withdrawn (i.e., disconnected) from the grooved surface of the mooring interface and a lock position in which the locking claws are meshed (i.e., connected) with the grooved surface of the mooring interface.

According to a first aspect of the present invention, each locking claw is included in a locking assembly guided to slide perpendicular, or at least partially perpendicular, to the longitudinal axis. In the context of the current invention, "partially perpendicular" must be interpreted as representing a movement in which a first component of the movement is perpendicular to the longitudinal axis, and a second component of the movement is parallel to the longitudinal axis, wherein "mainly (or mostly) perpendicular" is interpreted as a partially perpendicular movement in which the movement is predominantly perpendicular (i.e., the parallel component of the movement is smaller than the perpendicular component). A plurality of wedges are mounted to the base structure to move parallel (or partially parallel or mainly parallel; wherein the descriptions of "partially parallel" and "mainly parallel" are based on the descriptions of "partially perpendicular" and "mainly perpendicular" provided above) to the longitudinal axis and the hydraulic or pneumatic pistons may be operatively connected to lower down and raise up the wedges. Each wedge has wedge surfaces configured and arranged to interact with inclined surfaces of the locking assembly to move outwards and inwards the locking claws between the lock and release positions.

According to the first aspect of the invention, each wedge comprises at least one expansion wedge surface and at least one retraction wedge surface, wherein each locking assembly comprises at least one expansion inclined surface and at least one retraction inclined surface. The at least one expansion wedge surface is configured and arranged to interact with the at least one expansion inclined surface of the locking assembly, and the at least one retraction wedge surface is configured and arranged to interact with the at least one retraction inclined surface so as to move the locking claws outwards and inwards.

In some embodiments, each wedge may be configured as a part comprising a main wedge body and a base plate. The base plate may be configured to protrude laterally from the main wedge body, thereby forming one or two lateral wings. The main wedge body may be arranged in a central position with respect to two lateral wings, or may be arranged laterally (if there is only one lateral wing). The expansion and retraction wedge surfaces may be respectively configured as opposing faces of the base plate, wherein preferably the expansion wedge surfaces are parallel to the expansion wedge surfaces. The main wedge body may further comprise a guide surface arranged at an angle to the expansion and retraction wedge surfaces, wherein said guide surface may be configured such that, when the wedge slides into the inclined passage, the guide surface is pressed against a surface of the base structure, so that the pressing force is transmitted from the wedge to the locking claw to move the locking claw towards the grooved surface.

The expansion and retraction inclined surfaces of each locking assembly may be configured to form an inclined passage configured to receive the base plate of a respective wedge. The expansion and retraction inclined surfaces may be arranged mutually parallel. The inclined passage is also referred to as a slot (although lateral surfaces arranged to connect the respective expansion and retraction inclined surfaces are optional). The inclined passage may be open (i.e., it is not closed, but has an opening) on the retraction inclined surface, thereby allowing the movement of the main wedge body when the base plate slides within the inclined passage and limiting lateral displacement (i.e., in a direction transversal to the direction along which the base plate slides within the inclined passage) of the main wedge body when the base plate slides within the inclined passage.

According to some embodiments, the intermediate actuator may comprise one or more intermediate elastic elements. The one or more intermediate elastic elements may be at least partially housed in a respective cavity of the corresponding locking claw. The intermediate actuator may comprise at least one of the one or more expansion inclined surfaces of the locking assembly, wherein said at least one expansion inclined surface may be configured as a protruding expansion inclined surface. The at least one protruding expansion inclined surface may be configured to protrude from the cavity to come into contact with the at least one expansion wedge surface of the wedge. Thus, the at least one protruding expansion wedge surface may be configured to protrude into the inclined passage such that, when a wedge (or the base plate of a wedge) is inserted into the inclined passage, the expansion wedge surface of the wedge comes into contact with the protruding expansion inclined surface, therefore pushing the respective locking claw towards the respective grooved surface.

The intermediate actuators may be arranged with an angle of inclination with respect to a direction perpendicular to the longitudinal axis. The angle of inclination may be configured such that, when the intermediate actuator receives a compression force from the respective wedge, then intermediate actuator transmits a primary part (i.e., more than the <NUM>% of the force) of the force in a direction perpendicular to the longitudinal axis and secondary part (i.e., less than the <NUM>% of the force) of the force in a direction parallel to the longitudinal axis according to (i.e., aligned with) the movement of the wedge. The angle of inclination is an optional feature that ensures that the locking claws engage with the respective grooved surface in the locking position, while simultaneously a transversal force (i.e., parallel to the longitudinal axis) is provided, thereby generating a pretensioning force in the connection between the base structure and the mooring interface. Further, the transversal force helps to connect the locking ribs of the locking claws with the grooved surface. This last effect is especially important when the locking ribs are configured in a tooth-shaped pattern, and is even more especially important when said tooth-shaped pattern has an angle leaning towards a direction contrary to a direction of connection of the base structure with the mooring interface along the longitudinal axis. The angle of inclination may be in the range <NUM> to <NUM> degrees, preferably <NUM> to <NUM> degrees and, more preferably, <NUM> to <NUM> degrees. In other embodiments, the intermediate actuators may be arranged perpendicular to the longitudinal axis.

The protruding expansion inclined surface of the intermediate actuator may be arranged on the at least one intermediate elastic element. Optionally, the intermediate actuator may further comprise a push element connected to an end of the at least one intermediate elastic element, such that the protruding expansion inclined surface of the intermediate actuator is arranged on the push element. In preferred embodiments, the push element may be configured to have a wider cross-section area than the at least one intermediate elastic element. The cavity of the respective locking claw in which the intermediate actuator is housed comprises a lateral wall surrounding the cavity. Preferably, at least a part of said lateral wall may be configured to provide sliding contact with the push element and to remain separated from the intermediate elastic element. This may be achieved by providing a straight wall dimension to receive the wider cross-section of the push element. Thereby, a space is created between the intermediate elastic element and the part of the lateral wall configured to provide sliding contact with the push element, such that the friction between the cavity the lateral wall of the cavity and the intermediate elastic element is notably reduced.

To secure the alignment, the plurality of wedges may be, for example, peripherally or perimetrically (e.g., circumferentially) arranged on an optional actuator ring that is lowered down and raised up by means of the multiple hydraulic or pneumatic pistons which may have a first end connected to an optional collet arranged on top of the base structure and a second end connected to the actuator ring. In a coupling manoeuvre according to some embodiments, the actuator ring may be lowered down by the hydraulic or pneumatic pistons and each wedge may push out one of the corresponding locking claws to the lock position through the interaction with an intermediate actuator comprising one or more intermediate elastic elements, such as rubber mounts, of the locking assembly.

In the lock position, each claw is configured to press against the grooved surface of the mooring interface and is locked in place by its alignment with the grooves of the ring-shaped cavity. The intermediate elastic elements are located behind each locking claw and are used to ensure that the claws are pressed against the grooves with a known force, coming from the known stiffness of the intermediate elastic element, which remains preloaded once the coupling is engaged. This makes it so the locking force in the device is almost independent to manufacturing tolerance or in the presence of wear, which may otherwise lead to very large and difficult to estimate variations in the force exerted by each individual claw.

Decoupling manoeuvre is the exact same of the coupling manoeuvre described above but in reverse. In the decoupling manoeuvre, the hydraulic or pneumatic pistons are actuated to raise up the actuator ring thereby the wedges pull in the locking claws, preload on the intermediate elastic elements is released and thus the locking claws are moved to the release position and withdrawn from the grooved surface of the mooring interface. The base structure of the quick connector can be then taken out of the mooring interface attached to the mooring system and thereby the offshore floating structure is decoupled from the pre-laid mooring system.

In an alternative embodiment, the wedges may be configured and arranged so that the wedges push out the locking claws to the lock position when the actuator ring is raised up and the wedges pull in the locking claws to the release position when the actuator ring is lowered down.

According to a second aspect of the invention, the locking claws are guided with respect to the base structure to slide perpendicular (or at least partially perpendicular or mainly perpendicular) to the longitudinal axis, and an intermediate elastic element is interposed between each locking claw and the base structure. In the second aspect of the invention, the intermediate elastic elements are fluid-dynamically expansible and retractable and the fluid-dynamic device comprises a source of pressurized fluid, a valve arrangement and a fluid conduit. Each intermediate elastic element has an inner cavity which is in fluid communication with the source of pressurized fluid through the fluid conduit and through the valve arrangement.

With this construction, when pressurized fluid is injected into the inner cavity of the intermediate elastic element by the fluid-dynamic device, the intermediate elastic element expands and makes the corresponding locking claw to move outwards to the lock position. Inversely, when pressurized fluid is drawn out from the inner cavity of the intermediate elastic element by the fluid-dynamic device, the intermediate elastic element retracts thus making the corresponding locking claw to move inwards to the release position.

Another alternative embodiment is envisaged wherein the base structure of the quick connector may be shaped as the outer female member and the mooring interface is shaped as the inner male member, so that the base structure is configured to receive therein the mooring interface and to match it geometrically. Typically, these can be a conical geometry, spherical, or a combination of these.

Preferred embodiments of the quick connector are described below with reference to the attached drawings, in which:.

Referring first to <FIG>, reference sign <NUM> designates a quick connector for coupling an offshore floating structure <NUM> to a pre-laid mooring system <NUM> according to an embodiment of the present invention.

In the shown embodiment, the offshore floating structure <NUM> is configured as a weathervaning structure that supports a floating offshore wind turbine <NUM> and that comprises an upper body <NUM> partially submerged with respect to the mean water level <NUM>, and the pre-laid mooring system <NUM> is configured as a tension leg platform type comprising a submerged floating lower body <NUM> linked to the seabed <NUM> by means of a plurality of mooring lines <NUM>. However, it is noted that the particular configurations for the floating structure <NUM> and for the pre-laid mooring <NUM> system are merely illustrative and not limiting, since other configurations for the floating structure <NUM> and for the pre-laid mooring system <NUM> are compatible with the quick connector <NUM> of <FIG>.

Referring to <FIG>, the quick connector <NUM> comprises a base structure <NUM> configured to be coupled to the upper body <NUM> of the offshore floating structure <NUM>. In embodiments compatible with the embodiment of <FIG> the base structure may be coupled (preferably, rotatably coupled) by means of a yaw member <NUM> and a mooring interface <NUM> attached to the lower body <NUM> of the pre-laid mooring system. The quick connector <NUM> further comprises a locking mechanism which is fluid-dynamically actuated to couple and decouple the base structure <NUM> from the mooring interface <NUM> thereby the offshore floating structure <NUM> may be quickly coupled and decoupled from the pre-laid mooring system <NUM>. For example, the locking mechanism is hydraulically or pneumatically actuated.

The base structure <NUM> is designed as an inner male member having a longitudinal axis <NUM> aligned with an axis about which the offshore floating structure <NUM> may weathervane, and the mooring interface <NUM> is configured as an outer female member configured to receive in a fit manner the base structure <NUM> therein. However, in some embodiments of the invention, this solution may be adapted to be used with base structure <NUM> configured as an outer female member configured to receive in a fit manner the mooring interface <NUM> configured as an inner male.

As better shown in <FIG>, the base structure <NUM> is coupled to an optional yaw member <NUM> which is in turn rotatably coupled to a pass-through passage <NUM> of the upper body <NUM> of the offshore floating structure by bearings <NUM> coaxial to the longitudinal axis <NUM>. The yaw member <NUM>, the base structure <NUM> and the mooring interface <NUM> have a hollow interior, and the lower body <NUM> of the pre-laid mooring system has a pass-through passage <NUM> aligned with the longitudinal axis <NUM>. An electric conductor line <NUM> (shown in <FIG>) conducting electricity generated by the floating offshore wind turbine <NUM> is installed through the passage <NUM> of the lower body <NUM> and through the hollow interior of the yaw member <NUM>, the base structure <NUM> and the mooring interface <NUM>.

As shown in <FIG>, an optional collet <NUM> is arranged on top of the base structure <NUM> and connected thereto by screws <NUM>. The yaw member <NUM> has a cylindrical portion coaxially arranged inside a cylindrical portion of the base structure <NUM> and elastic coupling elements <NUM>, <NUM> are arranged between the yaw member <NUM> and the base structure <NUM>, and also between the yaw member <NUM> and the collet <NUM>. The elastic coupling elements <NUM>, <NUM> include upper elastic coupling elements <NUM> and lower elastic coupling elements <NUM>. The upper elastic coupling elements <NUM> are located between upper outer conical surfaces <NUM> of the yaw member <NUM> and upper inner conical surfaces <NUM> of the collet <NUM>. The lower elastic coupling elements <NUM> are located between lower outer conical surfaces <NUM> of the yaw member <NUM> and lower inner conical surfaces <NUM> of the base structure <NUM>. The upper outer and inner conical surfaces <NUM>, <NUM> and the lower outer and inner conical surfaces <NUM>, <NUM> are coaxial to the longitudinal axis <NUM> of the base structure <NUM> and have opposite cone or sphere angles.

Alternatively, upper outer and inner spherical surfaces and lower outer and inner spherical surfaces may be provided instead of the upper outer and inner conical surfaces <NUM>, <NUM> and lower outer and inner conical surfaces <NUM>, <NUM>.

The locking mechanism comprises a plurality of locking assemblies <NUM> movably mounted on the base structure <NUM>, radially arranged and distributed around the longitudinal axis <NUM>. Each locking assembly <NUM> is guided to slide perpendicular (although in some compatible embodiments the sliding may be at least partially perpendicular) to the longitudinal axis <NUM> and includes a locking claw <NUM> having a plurality of locking ribs 10a facing outwards, wherein the locking ribs 10a are preferably configured as horizontal locking ribs 10a. The mooring interface <NUM> has a ring-shaped portion sized to receive therein a region of the base structure <NUM> where the locking assemblies <NUM> are mounted, and a grooved surface <NUM> having circumferential grooves is formed on an inner surface of the ring-shaped portion of the mooring interface <NUM>.

The base structure <NUM> and the mooring interface <NUM> are configured so that once coupled together the locking assemblies <NUM> are arranged at a set height in which the locking ribs 10a of the locking claws <NUM> are facing the circumferential grooves of the grooved surface <NUM> formed in the mooring interface <NUM>.

The locking mechanism further comprises a plurality of wedges <NUM> attached to an actuator ring <NUM> arranged around the base structure <NUM> and guided to move parallel (or at least partially parallel) to the longitudinal axis <NUM> and a plurality of hydraulic pistons <NUM> mounted on the base structure <NUM> and operatively connected to lower down and raise up the actuator ring <NUM> together with the wedges <NUM> attached thereto. In the shown embodiment, each hydraulic piston <NUM> has a first end 8a connected to the collet <NUM> and a second end 8b connected to the actuator ring <NUM>.

Alternatively, the first end 8a of each wedge <NUM> may be connected to any other element of the base structure <NUM> and/or the second end 8b of each wedge <NUM> may be directly connected to one of the wedges <NUM> and the actuator ring <NUM> may be omitted.

Anyway, the hydraulic pistons <NUM> are operatively connected to lower down and raise up the wedges <NUM>, and each wedge <NUM> has wedge surfaces <NUM>, <NUM> configured and arranged to interact with inclined surfaces <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> of one of the locking assemblies <NUM> so as to move outwards and inwards the locking claws <NUM> included in the locking assemblies <NUM> between a release position (shown in <FIG>) in which the locking claws <NUM> are withdrawn from the grooved surface <NUM> of the mooring interface <NUM> and a lock position (shown in <FIG>) in which the locking claws <NUM> are meshed with the grooved surface <NUM> of the mooring interface <NUM>.

An intermediate actuator comprising an intermediate elastic element <NUM> is interposed between each wedge <NUM> and the locking claw <NUM> of the corresponding locking assembly <NUM>. The intermediate elastic elements <NUM> may be selected with a given stiffness suitable to ensure that the locking claws <NUM> are pressed against the grooved surface <NUM> with a known force.

<FIG> shows an isolated view of one of the wedges <NUM> according to several embodiments of the invention for the sake of clarity in the drawing. The wedge <NUM> has an expansion wedge surface <NUM> facing outwards and a retraction wedge surface <NUM> facing inwards. The expansion wedge surface <NUM> and the retraction wedge surface <NUM> are mutually parallel. Optional lugs <NUM> are provided on top of the wedge <NUM> for connection to the second end 8b of the corresponding hydraulic piston <NUM> and a vertical guide surface <NUM> is formed on an inner side of the wedge <NUM>.

<FIG> depicts a wedge configured as part comprising a main wedge body and a base plate. The base plate is configured to protrude laterally from the main wedge body, thereby forming two lateral wings. The expansion wedge surface <NUM> and the retraction wedge surface <NUM> are formed on the base plate (i.e., they are integral parts of the base plate), preferably as being mutually parallel. In preferred embodiments, the wedge is configured as a monobloc part comprising both the main wedge body and the base plate. The base plate of <FIG> is shown as comprising two lateral wings, so that the main wedge body is arranged centrally with respect to both wings. However, according to other embodiments, the base plate may comprise a single lateral wing, so that the main wedge body may be arranged laterally with respect to said single lateral wing.

<FIG> and <FIG> show one of the locking assemblies <NUM> which comprises a locking claw <NUM> and an intermediate actuator comprising an intermediate elastic element <NUM>. Indeed, in this particular configuration, the intermediate actuator only comprises an intermediate elastic element <NUM> (although the intermediate actuator may comprise one or more intermediate elastic elements <NUM>), so that the intermediate actuator is configured as an intermediate elastic element <NUM>. The locking assembly <NUM> comprises locking claw <NUM> with horizontal locking ribs 10a on an outer side thereof, expansion inclined surfaces <NUM>, <NUM> and a retraction inclined surface <NUM> near an inner side. The expansion inclined surfaces <NUM>, <NUM> and the retraction inclined surface are configured to form an inclined passage near an inner side. The inclined passage is configured to receive the expansion wedge surface <NUM> and the retraction wedge surface <NUM> of a wedge <NUM>, preferably when these surfaces <NUM>, <NUM> are formed on a base plate. The inclined passage may be configured as a slot. A cavity is formed in the locking claw <NUM> open in an outer side of the inclined passage and a retraction inclined surface <NUM> is formed on an inner side of the inclined passage. The cavity is formed in the locking claw <NUM> such that the cavity is accessible from the inclined passage. The inclined passage is open inwards in front of the cavity to allow the movement of the main wedge body when the base plate of the wedge slides within the inclined passage. The intermediate actuator comprising an intermediate elastic element <NUM> is housed in the cavity and has an expansion inclined surface <NUM> protruding into the inclined passage. Thus, it is noted that at least one of the expansion inclined surfaces <NUM> may be configured as an expansion inclined surface (or protruding expansion inclined surface <NUM>) formed in the intermediate actuator. In particular, the protruding expansion inclined surface <NUM> may be configured to protrude into the inclined passage such that, when a wedge <NUM> is inserted into the inclined passage, the expansion wedge surface <NUM> of the wedge <NUM> comes into contact with the protruding expansion inclined surface <NUM>.

The expansion inclined surface <NUM> and the retraction inclined surface <NUM> are preferably mutually parallel and parallel to the expansion wedge surface <NUM> and the retraction wedge surface <NUM> of the wedge <NUM>. Further, the locking assembly <NUM> is shown as comprising an optional expansion inclined surface <NUM> (also referred to as secondary expansion inclined surface), which is configured such that, when the expansion wedge surface <NUM> interacts with the protruding expansion inclined surface <NUM> so that the intermediate elastic element <NUM> receives a predetermined compression force, then the secondary expansion inclined surface <NUM> comes into contact with the expansion wedge surface <NUM>, the secondary expansion inclined surface <NUM> being preferably located on the locking claw <NUM>. The secondary expansion inclined surface <NUM> may be configured as a surface arranged to at least partially surround the protruding expansion inclined surface <NUM>. In some embodiments, the predetermined compression force may be selected to be greater than a range of operating compression forces of the quick connector under standard operating conditions. Thus, in such cases, the locking assembly <NUM> may be configured such that, contact between the secondary inclined surface <NUM> and the expansion wedge surface <NUM> may take place only when an extraordinary compression force is generated (e.g., due to a non-standard operation, such as in a failure situation), or when the intermediate actuator (e.g., the intermediate elastic element <NUM>) is deteriorated. In these cases, the contact of the expansion wedge surface <NUM> with the inclined secondary surface <NUM> provides a distribution of forces over a larger surface area, thus reducing the stress concentration.

It is noted that the retraction inclined surface <NUM> shown in <FIG> may be interpreted as comprising two surfaces arranged on a same single plane, wherein each of these surfaces are arranged on a respective side of the inclined. The same duplicity may be applicable to the retraction wedge surface <NUM> shown in <FIG>, wherein the said surface may be interpreted as comprising two independent surfaces. Therefore, in compatible embodiments, a wedge <NUM> may comprise one or more expansion wedge surfaces <NUM> and one or more retraction inclined surfaces <NUM>, and a locking assembly <NUM> may comprise one or more expansion inclined surfaces <NUM>, <NUM>, <NUM>, <NUM> and one or more retraction inclined surfaces <NUM>, <NUM>.

<FIG> shows a wedge <NUM> inserted into a locking assembly <NUM> compatible with any of the embodiments shown in <FIG>, <FIG> depicts a wedge <NUM> inserted in the inclined passage of the locking claw <NUM>. The expansion wedge surface <NUM> of the wedge <NUM> is configured and arranged to interact with one or more of the expansion inclined surfaces <NUM>, <NUM>, <NUM>, and the retraction wedge surface <NUM> of the wedge <NUM> is configured and arranged to interact with the retraction inclined surface <NUM> of the locking claw <NUM>.

The inclined surfaces <NUM>, <NUM>, <NUM> and the wedge surfaces <NUM>, <NUM> are configured so that when the wedge <NUM> is impelled by the hydraulic piston <NUM> to perform a vertical movement towards an expansion direction, which in this embodiment is a downwards movement, the wedge <NUM> makes the intermediate elastic element <NUM> together with the locking claw <NUM> to move outwards to the lock position, and when the wedge <NUM> is impelled by the hydraulic piston <NUM> to perform a vertical movement towards a retraction direction, which in this embodiment is an upwards movement, the wedge <NUM> makes the locking claw <NUM> together with the intermediate elastic element <NUM> to move outwards to the lock position.

<FIG> shows a locking assembly <NUM> according to another embodiment which only differs from the one described above with reference to <FIG> and <FIG> in that the intermediate actuator further comprises a push element <NUM> coupled to the intermediate elastic element <NUM> at an inner side thereof, such that the protruding expansion inclined surface <NUM> is now included in the push element <NUM>. Thus, the push element <NUM> has an expansion inclined surface <NUM> protruding into the inclined passage of the locking claw <NUM>. In this embodiment, the wedge <NUM> interacts with the locking assembly <NUM> as explained above with reference to <FIG> with the difference that here the expansion wedge surface <NUM> of the wedge <NUM> is configured and arranged to interact with the expansion inclined surface <NUM> of the push element <NUM>.

The embodiment of <FIG> further shows that the push element <NUM> is configured to have a wider cross-section area than the intermediate elastic element <NUM>, such that the push element <NUM> is configured to embrace a first end of the intermediate elastic element <NUM>, and wherein the cavity of the respective locking claw <NUM> in which the intermediate actuator is housed comprises a lateral wall, wherein at least a part of said lateral wall is configured to provide sliding contact with the push element <NUM> but not with the at least one intermediate elastic element <NUM> (i.e., the referred part of the wall is spaced apart from the elastic element <NUM>). This is an optional feature of the embodiment. Thereby, a space is created between the intermediate elastic element and the part of the lateral wall configured to provide sliding contact with the push element, such that the friction between the cavity the lateral wall of the cavity and the intermediate elastic element is notably reduced. In the embodiment of <FIG>, the intermediate elastic element <NUM> is configured with optional lateral ribs, which provide an additional structural rigidity to the intermediate elastic element, thereby ensuring a stable lineal compression of this element, even on those areas of the intermediate elastic element <NUM> that are spaced apart from the lateral wall of the cavity, therefore lacking lateral contact during the compression of the intermediate elastic element <NUM>.

Further, the embodiments shown in <FIG> show respective intermediate actuators arranged with an angle of inclination with respect to a direction perpendicular to the longitudinal axis <NUM>, said angle of inclination being configured such that, when the intermediate actuator receives a compression force from the respective wedge <NUM>, the intermediate actuator transmits a primary part (i.e. more than the <NUM>% of the force) of the force in a direction perpendicular to the longitudinal axis <NUM> and secondary part (i.e., less than the <NUM>% of the force) of the force in a direction parallel to the longitudinal axis <NUM> according to (i.e., aligned with) the movement of the wedge <NUM>. The angle of inclination is an optional feature that ensures that the locking claws <NUM> engage with the respective grooved surface <NUM> in the locking position, while providing a transversal force (i.e., parallel to the longitudinal axis <NUM>) that provides a pretensioning force in the connection between the base structure <NUM> and the mooring interface, while helping to connect the locking ribs 10a of the locking claws <NUM> with the grooved surface <NUM>. This last effect is especially important when the locking ribs 10a are configured in a tooth-shaped pattern, and is even more especially important when said tooth-shaped pattern having a leaning towards a direction contrary to a direction of connection of the base structure <NUM> with the mooring interface <NUM> along the longitudinal axis <NUM>. In other embodiments, the intermediate actuators may be arranged perpendicular to the longitudinal axis.

It is noted that the embodiment of <FIG> is also representative of the configuration shown in <FIG> when the reference sign <NUM> is replaced by the reference sign <NUM>, and when the reference sign <NUM> is replaced by the reference sign <NUM>. Thus, the protruding expansion inclined surface <NUM> of <FIG> may be interpreted as being representative of the protruding expansion inclined surface <NUM> of <FIG>, while the intermediate elastic element <NUM> shown in <FIG> may be interpreted as being representative of the push element <NUM> of <FIG> (the intermediate elastic element would be behind the push element <NUM> in this view, thereby not being visible).

<FIG> show a locking assembly <NUM> according to still another embodiment which comprises the locking claw <NUM>, the intermediate actuator with the intermediate elastic element <NUM> and an inner support <NUM>, wherein the locking claw <NUM> is linked at the inner side thereof to the inner support <NUM> and the intermediate actuator having the intermediate elastic elements <NUM> is interposed between the locking claw <NUM> and the inner support <NUM>. In this embodiment, the at least one expansion inclined surface <NUM> and the at least one retraction inclined surface <NUM> are arranged on the inner support forming an inclined passage near an inner side thereof. The inclined passage is open inwards with respect to the base structure <NUM> (in the same way as disclosed for the embodiment of <FIG>) and defines an expansion inclined surface <NUM> and a retraction inclined surface <NUM>.

The locking assembly <NUM> of <FIG> is configured to interact with the wedge <NUM> of <FIG>. The expansion inclined surface <NUM> and the retraction inclined surface <NUM> are mutually parallel and parallel to the expansion wedge surface <NUM> and the retraction wedge surface <NUM> of the wedge <NUM>. The expansion wedge surface <NUM> of the wedge <NUM> is configured and arranged to interact with the expansion inclined surface <NUM> of the inner support <NUM> in order to cause an outwards movement of the locking assembly <NUM> to the lock position and the retraction wedge surface <NUM> of the wedge <NUM> is configured and arranged to interact with the retraction inclined surface <NUM> of the inner support in order to cause an inwards movement of the locking assembly <NUM> to the release position.

<FIG> show a fluid-dynamically actuated locking mechanism and a locking assembly <NUM> according to still another embodiment. Each locking assembly <NUM> is guided with respect to the base structure <NUM> to slide perpendicular, or at least partially perpendicular, to the longitudinal axis <NUM> and comprises a locking claw <NUM> and an intermediate elastic element <NUM> which in this embodiment is interposed between each locking claw <NUM> and the base structure <NUM>. Each intermediate elastic element <NUM> is fluid-dynamically expansible and retractable by actuation of the fluid-dynamic device.

More specifically, as shown in <FIG>, the intermediate elastic element <NUM> has an inner cavity <NUM> and the fluid-dynamic device comprises a source of pressurized fluid <NUM>, a valve arrangement <NUM>, and a fluid conduit <NUM>. The inner cavity <NUM> of the intermediate elastic element <NUM> is in fluid communication with the source of pressurized fluid <NUM> through the fluid conduit <NUM> and through the valve arrangement <NUM>.

In the situation shown in <FIG>, the valve arrangement <NUM> is set to allow pressurized fluid to be exhausted from the inner cavity <NUM> of the intermediate elastic element <NUM> through the fluid conduit <NUM> (as shown by an arrow) thereby the intermediate elastic element <NUM> retracts and pulls the locking claw <NUM> inwards to the release position.

In the situation shown in <FIG>, the valve arrangement <NUM> is set to allow pressurized fluid from the source of pressurized fluid <NUM> to be injected to the inner cavity <NUM> of the intermediate elastic element <NUM> through the fluid conduit <NUM> (as shown by an arrow) thereby the intermediate elastic element <NUM> expands and pushes the locking claw <NUM> outwards to the lock position.

In summary, in one embodiment of the present invention shown in <FIG>, the quick connector <NUM> coupling an offshore floating structure to a pre-laid mooring system comprises the base structure <NUM>, being preferably configured as a cone that holds the circumferentially arranged locking assemblies <NUM>, and a cylinder that configured to keep the locking mechanism at a set height. A collet <NUM> preferably sits on top of the base structure <NUM> cylinder and is attached to the hydraulic pistons <NUM> of the fluid-dynamic device that connect the collet <NUM> to the actuator ring <NUM>, which is located outside of the base structure <NUM> cylinder. The elastic coupling elements <NUM> serve as an intermediate element between inner walls of the base structure <NUM> cylinder and the collet <NUM> and the yaw member <NUM> that is designed to be inserted into the base structure <NUM> of the quick connector. The main purpose of the elastic coupling elements <NUM> is to allow a limited relative motion and rotation between the yaw member <NUM> and the mooring interface <NUM>, resisting all other load components. It is also there to improve the self-alignment of the structure and protect it from possible impacts during the installation process.

The locking assemblies <NUM> sit within the base structure <NUM> cone and each consists of several parts such as: in one embodiment, a locking claw <NUM> and an intermediate elastic element <NUM>; in another embodiment, a locking claw <NUM>, an intermediate elastic element <NUM> and a push element <NUM>; in still another embodiment, a locking claw <NUM>, an intermediate elastic element <NUM> and an inner support <NUM>. Since the two or three parts fit together geometrically as described with reference to <FIG>, they are held together tightly at all times.

The actuator ring <NUM> has a set of wedges <NUM>, with each of them piercing the corresponding intermediate elastic element <NUM> or inner support <NUM> through the socket designed to match its shape. The released state of the quick connector, described with reference to <FIG>, shows the wedges <NUM> of the actuator ring <NUM> only partially inserted into the inner supports <NUM> to keep the locking claws retracted.

Once the base structure <NUM> of the quick connector <NUM> is guided into the receiving portion of the mooring interface <NUM>, with the longitudinal axis <NUM> of the base structure <NUM> in alignment with the vertical axis of the mooring interface <NUM>, and the base structure <NUM> is located at the set height in the mooring interface <NUM>, pistons <NUM> are actuated until lowering down the actuator ring <NUM>, thereby inserting the wedges <NUM> attached to the actuator ring <NUM> all the way down into the locking claws <NUM> or into the inner supports <NUM> linked to the locking claws <NUM>, depending on the embodiment. In so doing, the wedges <NUM> are pressed down on the intermediate elastic elements <NUM> or on the push elements connected to the intermediate elastic elements <NUM>, depending on the embodiment, thus driving the locking claws <NUM> away from the longitudinal axis <NUM> and out of the base structure <NUM> to the lock position. This makes the locking claws <NUM> to press against the inner grooved surface <NUM> of the mooring interface <NUM>, as described above with reference to <FIG>, thereby coupling the male portion of base structure <NUM> to the female portion of the mooring interface <NUM> and thus connecting the upper body <NUM> of the offshore floating structure to the lower body <NUM> of the pre-laid mooring system.

It is worth noting that, in the embodiment shown in <FIG>, <FIG>, only two of the hydraulic pistons <NUM> are strictly required to actuate the locking mechanism of the quick connector <NUM>. Thus, when more than two pistons are included, it is firstly to provide a more equally distributed force in the collet <NUM> and in the actuator ring <NUM>, and secondly as a redundancy measure, where for example the system has four or more pistons in two independent hydraulic systems, if one of the hydraulic systems fails there is still another fully operative hydraulic system to provide even loading to the collet and to the actuator ring <NUM>.

Different stages in a coupling method or manoeuvre for coupling an offshore floating structure to a pre-laid mooring system by using the quick connector according to the embodiment of the present invention shown in Figs. <NUM> to <NUM> are as follows:.

A decoupling method or manoeuvre for decoupling the offshore floating structure from the pre-laid mooring system by using the quick connector of the present invention comprises performing the stages above in a reverse manner.

In another embodiment of the present invention shown in <FIG>, the quick connector <NUM> coupling an offshore floating structure to a pre-laid mooring system comprises locking assemblies <NUM> guided with respect to the base structure <NUM> to slide perpendicular to the longitudinal axis <NUM>, and each locking assembly <NUM> comprises a locking claw <NUM> and a fluid-dynamically expansible and retractable intermediate elastic element <NUM> interposed between the locking claw <NUM> and the base structure <NUM>. The fluid-dynamic device is configured to inject pressurized fluid to an inner cavity <NUM> of each intermediate elastic element <NUM> so as to expand it and move the corresponding locking claw <NUM> outwards to the lock position, or to draw out pressurized fluid from the inner cavity <NUM> of each intermediate elastic element <NUM> so as to retract it and move the corresponding locking claw <NUM> inwards to the release position.

Claim 1:
A quick connector (<NUM>) for coupling, in alignment with a longitudinal axis (<NUM>), an offshore floating structure (<NUM>) to a pre-laid mooring system (<NUM>), the quick connector (<NUM>) comprising:
a base structure (<NUM>) configured to be coupled to an upper body (<NUM>) of the offshore floating structure (<NUM>);
a mooring interface (<NUM>) configured to be attached to a lower body (<NUM>) of the pre-laid mooring system (<NUM>); and
a locking mechanism fluid-dynamically actuated to couple and decouple the base structure (<NUM>) from the mooring interface (<NUM>),
wherein the locking mechanism comprises: a grooved surface (<NUM>) formed in the mooring interface (<NUM>);
locking claws (<NUM>) movably mounted on the base structure (<NUM>); and
a fluid-dynamic device associated to the base structure (<NUM>) and operatively connected to move the locking claws (<NUM>) between a release position in which the locking claws (<NUM>) are withdrawn from the grooved surface (<NUM>) of the mooring interface (<NUM>) and a lock position in which the locking claws (<NUM>) are meshed with the grooved surface (<NUM>) of the mooring interface (<NUM>);
characterized in that each locking claw (<NUM>) is included in a locking assembly (<NUM>) and is guided to slide at least partially perpendicular to the longitudinal axis (<NUM>), wherein the quick connector (<NUM>) further comprises wedges (<NUM>) configured to be mounted to the base structure (<NUM>) so as to move at least partially parallel to the longitudinal axis (<NUM>), wherein the fluid-dynamic device is operatively connected to lower down and raise up the wedges (<NUM>), wherein each wedge (<NUM>) comprises at least one expansion wedge surface (<NUM>) and at least one retraction wedge surface (<NUM>), wherein each locking assembly (<NUM>) comprises at least one expansion inclined surface (<NUM>, <NUM>, <NUM>, <NUM>) and at least one retraction inclined surface (<NUM>, <NUM>), wherein the at least one expansion wedge surface (<NUM>) is configured and arranged to interact with the at least one expansion inclined surface (<NUM>, <NUM>, <NUM>, <NUM>) of the locking assembly (<NUM>) and the at least one retraction wedge surface (<NUM>) is configured and arranged to interact with the at least one retraction inclined surface (<NUM>, <NUM>) so as to move the locking claws (<NUM>) outwards and inwards.