Swivel-based mooring device and system

Abstract

A swivel-based mooring device is disclosed for use with marine energy devices, aquaculture systems, and port or harbor infrastructure, the device being configured to simplify deployment and improve long-term operational reliability in dynamic marine environments. In some embodiments, the device integrates an electrical slip-ring and a fluid rotary-union or swivel-joint within a single axial structure to enable continuous transmission of electrical power and fluids while permitting relative rotation between mooring components through up to 360 degrees. In some embodiments, an integrated spring or damper mechanism is provided to absorb axial loads and dynamic tension in electrical and fluid lines without materially extracting useful energy from the coupled marine device.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to, and the benefit of, co-pending U.S. provisional application no: 63 / 763,414, filed on Feb. 26, 2025 the entire contents of which are hereby incorporated by reference in their entirety.BACKGROUND OF THE INVENTION

[0002] Marine and offshore installations such as marine energy systems, aquaculture facilities, and port or harbor infrastructure commonly rely on mooring systems to maintain positional stability while accommodating environmental forces including waves, currents, and tides. These mooring systems often incorporate electrical and fluid connections to enable power transmission, data communication, or fluid transfer between a floating structure and a fixed or remote location. Conventional approaches typically employ separate components to manage mechanical loading, electrical transmission, and fluid conveyance, which can increase system complexity and installation time.

[0003] Existing mooring and connection architectures may also be susceptible to reliability challenges arising from torsional loading, axial motion, and cyclic fatigue induced by marine environments. In particular, twisting of electrical cables or fluid lines, as well as axial loads transmitted through these connections, can contribute to wear, leakage, or failure over time. Additionally, some systems rely on multiple anchors or secondary restraint structures, which can increase deployment costs and complicate maintenance operations, especially in offshore or remote settings.BRIEF SUMMARY OF THE INVENTION

[0004] A swivel-based mooring device is disclosed for use with marine energy devices, aquaculture systems, and port or harbor infrastructure, the device being configured to simplify deployment and improve long-term operational reliability in dynamic marine environments. In some embodiments, the device integrates an electrical slip-ring and a fluid rotary-union or swivel-joint within a single axial structure to enable continuous transmission of electrical power and fluids while permitting relative rotation between mooring components through up to 360 degrees. In some embodiments, an integrated spring or damper mechanism is provided to absorb axial loads and dynamic tension in electrical and fluid lines without materially extracting useful energy from the coupled marine device.BRIEF DESCRIPTION OF THE DRAWINGS

[0005] FIG. 1 illustrates the system block diagram showing an example swivel-based mooring device connected to a Wave Energy Converter (WEC) or Marine Energy Device device and a mooring line within an ocean.

[0006] FIG. 2 shows a cross-sectional view of one example of a swivel-based mooring device.

[0007] FIG. 3 shows a cross-sectional view of one example swivel-based mooring device.

[0008] FIG. 4 shows a cross-sectional view of one example swivel-based mooring device.

[0009] FIG. 5 shows a cross-sectional view of one example swivel-based mooring device.DETAILED DESCRIPTION AND BEST MODE OF IMPLEMENTATION

[0010] The present invention now will be described more fully hereinafter in the following detailed description of the invention, in which some, but not all embodiments of the invention are described. Indeed, this invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements.

[0011] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. As used herein, the singular forms “a,”“an,” and “the” are intended to include the plural forms as well as the singular forms, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and / or “comprising,” when used in this specification, specify the presence of stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof.

[0012] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one having ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0013] In describing the invention, it will be understood that a number of techniques and steps are disclosed. Each of these has individual benefit and each can also be used in conjunction with one or more, or in some cases all, of the other disclosed techniques. Accordingly, for the sake of clarity, this description will refrain from repeating every possible combination of the individual steps in an unnecessary fashion. Nevertheless, the specification and claims should be read with the understanding that such combinations are entirely within the scope of the invention and the claims. In some embodiments, a swivel-based mooring device is configured to provide a combined mechanical, electrical, and fluid interface between a marine energy device, aquaculture installation, or port or harbor infrastructure and a seabed anchoring or fixed reference structure. The device is intended to simplify deployment and improve long-term reliability by integrating rotational, load-absorbing, electrical transmission, and fluid conveyance functions within a single modular assembly. The device may be used in offshore, nearshore, or sheltered marine environments and may be adapted for permanent or semi-permanent installations.

[0014] In some embodiments, the swivel-based mooring device includes a central structural housing that supports axial load transfer between an upper connection interface and a lower connection interface. The housing may be fabricated from corrosion-resistant materials such as stainless steel, duplex steel, titanium alloys, or composite materials suitable for prolonged exposure to seawater. The housing may be dimensioned to accommodate internal components including slip rings, rotary unions, and spring or damper elements while maintaining structural integrity under cyclic loading conditions.

[0015] In some embodiments, the upper connection interface is configured to couple directly to a marine energy device, such as a wave energy converter (300), or to an intermediate tether or structural member associated with such a device. The upper connection interface may include mechanical attachment features such as flanges, threaded couplings, clevis pins, or shackles designed to transmit tensile and compressive loads. The upper connection interface may also provide entry points for electrical conductors (500) and fluid conduits (600) originating from the marine energy device or associated systems.

[0016] In some embodiments, the lower connection interface is configured to couple to a seabed anchor, foundation pile, gravity base, or other fixed or semi-fixed reference structure. The lower connection interface may be designed to transmit axial loads directly to the anchoring system without requiring a secondary anchor. By eliminating the need for a secondary anchor, deployment complexity and seabed footprint may be reduced, and installation operations may be simplified.

[0017] In some embodiments, the swivel-based mooring device includes an integrated slip-ring assembly (103, 152) configured to transmit electrical power, control signals, or data across a rotating interface. The slip-ring assembly may include multiple conductive channels to support single-phase or multi-phase electrical power transmission, as well as low-voltage signal transmission. The slip-ring assembly may be sealed to prevent ingress of seawater or particulates and may incorporate materials selected to minimize electrical resistance and wear over extended operational lifetimes.

[0018] In some embodiments, the integrated slip-ring assembly (103, 152) is arranged concentrically within the housing such that rotational motion between the upper and lower connection interfaces does not induce torsional stress in the electrical conductors (500). The slip-ring assembly may allow continuous 360-degree rotation in either direction, thereby accommodating changes in heading or orientation of the marine energy device due to wave action, currents, or tidal forces.

[0019] In some embodiments, the swivel-based mooring device further includes an integrated rotary-union or swivel-joint assembly (104, 152) configured to transmit fluid through one or more internal flow paths while permitting relative rotation between the upper and lower connection interfaces. The fluid may include desalinated water, pressurized hydraulic fluid, cooling fluid, or other liquids produced or consumed by the marine energy device. The rotary-union assembly may include seals, bearings, and internal channels designed to maintain fluid integrity under pressure and rotational motion.

[0020] In some embodiments, the integrated rotary-union or swivel-joint assembly (104, 152) is co-axially aligned with the slip-ring assembly (103, 152), enabling both electrical and fluid transmission through a common rotational axis. This co-axial arrangement may reduce overall device size and complexity while improving alignment and load distribution. The rotary-union assembly may be designed to support multiple independent fluid channels, each isolated from the others to prevent cross-contamination.

[0021] In some embodiments, the swivel-based mooring device includes an integrated spring or damper mechanism (105, 155) configured to absorb axial loads transmitted through the electrical conductors (500) and fluid conduits (600). The spring or damper mechanism may include mechanical springs, elastomeric elements, hydraulic dampers, or combinations thereof. The mechanism may be arranged such that axial loads induced by wave motion or device heave are absorbed locally within the mooring device rather than being transmitted directly to the electrical or fluid connections.

[0022] In some embodiments, the integrated spring or damper mechanism (105, 155) is configured to operate independently of the primary energy conversion mechanism of the marine energy device, such that potential energy is not diverted away from the energy harvesting process. For example, when used with a wave energy converter (300), the spring or damper mechanism may absorb high-frequency or transient axial loads while allowing the primary power take-off system of the wave energy converter to operate as intended.

[0023] In some embodiments, the spring or damper mechanism (105, 155) is positioned between the slip-ring assembly (103, 152) and the rotary-union assembly (104, 152) or between one of these assemblies and the structural housing. This positioning may allow axial compliance while maintaining electrical and fluid continuity. The stiffness and damping characteristics of the mechanism may be selected based on expected environmental loads, device mass, and operational conditions.

[0024] In some embodiments, the swivel-based mooring device is configured to accommodate combined axial, torsional, and bending loads. Internal bearings may be provided to support rotational motion while maintaining alignment of internal components. These bearings may include roller bearings, thrust bearings, or journal bearings fabricated from materials selected for corrosion resistance and low friction under marine conditions.

[0025] In some embodiments, the electrical conductors (500) entering the swivel-based mooring device from the marine energy device are routed through strain relief features before engaging the slip-ring assembly (103, 152). These strain relief features may include clamps, flexible sections, or compliant mounts that reduce stress concentrations and improve fatigue life. Similarly, the fluid conduits (600) may be routed through compliant interfaces before engaging the rotary-union assembly (104, 152).

[0026] In some embodiments, the swivel-based mooring device is modular, allowing individual components such as the slip-ring assembly (103, 152), rotary-union assembly (104, 152), or spring or damper mechanism (105, 155) to be replaced or serviced independently. This modularity may reduce maintenance costs and downtime, particularly in offshore installations where access is limited.

[0027] In some embodiments, the device may include internal pressure compensation, marine dielectric grease, or oil-filled cavities to balance internal and external pressures and protect sensitive components from seawater ingress. Pressure compensation systems may include flexible bladders, pistons, or diaphragms that respond to changes in ambient pressure with depth.

[0028] In some embodiments, the swivel-based mooring device may be configured for use with multiple types of marine installations beyond wave energy converters. For example, the device may be used to support aquaculture cages requiring electrical power and freshwater supply, or port infrastructure requiring power and fluid connections to floating platforms. The integrated nature of the device may reduce the number of discrete components required in such installations.

[0029] In some embodiments, the device may be scaled in size and capacity depending on application requirements. Larger embodiments may support higher power transmission and fluid flow rates, while smaller embodiments may be used for low-power sensing platforms or auxiliary systems. Scaling may involve adjusting housing dimensions, conductor sizes, seal ratings, and spring or damper characteristics.

[0030] In some embodiments, the swivel-based mooring device may be installed as part of a single-point mooring configuration, allowing the connected marine structure to freely weathervane about the mooring axis. This capability may reduce mooring line loads and improve survivability in changing environmental conditions.

[0031] In some embodiments, installation of the swivel-based mooring device may involve pre-assembling the device onshore, connecting the electrical conductors (500) and fluid conduits (600) to the marine energy device, and lowering the assembly into position using a vessel or crane. The lower connection interface may then be secured to the seabed anchor or foundation without the need for additional anchors or complex alignment procedures.

[0032] In some embodiments, the integrated design of the swivel-based mooring device may reduce failure modes associated with twisting, kinking, or over-tensioning of electrical and fluid lines. By allowing continuous axial rotation and providing axial compliance, the device may extend the service life of these connections under cyclic marine loading.

[0033] In some embodiments, the swivel-based mooring device may incorporate sensors to monitor parameters such as load, rotation angle, temperature, or leakage. These sensors may be used for condition monitoring and predictive maintenance. Sensor data may be transmitted through the electrical conductors (500) to a remote monitoring system.

[0034] In some embodiments, the device may include external protective coatings or sacrificial anodes to mitigate corrosion. The selection of coatings and cathodic protection systems may be tailored to the expected deployment environment and service life requirements.

[0035] In some embodiments, the swivel-based mooring device may be integrated into a broader marine energy system architecture, serving as a critical interface between energy generation, transmission, and anchoring subsystems. By consolidating multiple functions into a single device, overall system complexity may be reduced, and deployment timelines may be shortened.

[0036] In some embodiments, the swivel-based mooring device described herein may be adapted to future marine technologies that require combined mechanical, electrical, and fluid interfaces. The described embodiments are intended to illustrate representative configurations, and variations in form, materials, and arrangement may be implemented without departing from the scope of the appended claims.

[0037] In some embodiments, a swivel-based mooring device 100 is provided for mooring marine device installations including marine energy devices, aquaculture systems, and port or harbor infrastructure, wherein the swivel-based mooring device 100 is configured to simplify deployment and improve operational reliability. The swivel-based mooring device 100 includes a structural housing 101 defining an upper connection interface 102 configured to couple to a marine device 300 and a lower connection interface 151 configured to couple to a seabed anchor or fixed reference structure without the use of a secondary anchor. The swivel-based mooring device 100 further includes an integrated slip-ring assembly 103 configured to transmit electrical power and signals 500 through the swivel-based mooring device 100 while permitting relative axial rotation, and an integrated rotary-union or swivel-joint assembly 104 configured to transmit one or more fluids 600 through the swivel-based mooring device 100 while permitting relative axial rotation. In some embodiments, the slip-ring assembly 103 and the rotary-union or swivel-joint assembly 104 are co-axially aligned within the structural housing 101 to allow continuous 360-degree rotation between the upper connection interface 102 and the lower connection interface 151 without inducing torsional stress in electrical conductors 500 or fluid conduits 600.

[0038] In some embodiments, the swivel-based mooring device 100 further includes an integrated spring or damper mechanism 155 positioned within the structural housing 101 and configured to absorb axial loads transmitted through the electrical conductors 500 and the fluid conduits 600 while remaining mechanically decoupled from a primary energy conversion mechanism of an associated marine energy device 300. The integrated spring or damper mechanism 155 may include mechanical springs, elastomeric elements, hydraulic dampers, or combinations thereof, and may be configured to attenuate transient or cyclic axial loads induced by wave motion, ocean currents, or tidal forces. In some embodiments, the swivel-based mooring device 100 further includes one or more bearing assemblies 106 configured to support combined axial and rotational loads, strain relief features 107 associated with the electrical conductors 500 and the fluid conduits 600, and sealed or pressure-compensated internal cavities configured to protect internal components from seawater ingress and corrosion.

[0039] In some embodiments, the swivel-based mooring device 100 is configured as a modular assembly in which the slip-ring assembly 103, the rotary-union or swivel-joint assembly 104, and the integrated spring or damper mechanism 155 may be independently accessed, serviced, or replaced without removal of the entire swivel-based mooring device 100 from service. The swivel-based mooring device 100 may be scaled to accommodate different electrical power transmission levels and fluid flow capacities, and may be deployed as part of a single-point mooring system configured to permit free rotational alignment of a connected marine structure about a vertical mooring axis. In some embodiments, the swivel-based mooring device 100 reduces failure modes associated with twisting, kinking, fatigue, or over-tensioning of electrical conductors 500 and fluid conduits 600, thereby improving operational reliability and extending service life in harsh marine environments. While certain embodiments have been described herein, variations in structure, materials, and component arrangement may be implemented without departing from the scope of the appended claims.Part No. Part Name100 Swivel-Based Mooring Device: Shell-Loaded Topology

[0041] 101 Outer Shell

[0042] 102 Inner Shell

[0043] 103 Slip Ring

[0044] 104 Rotary Union

[0045] 105 Spring / Damper Element

[0046] 106 Chain Attachment

[0047] 107 Bearing / Seal

[0048] 150 Swivel-Based Mooring Device: Through-Bore Topology

[0049] 151 Shell

[0050] 152 Rotary Union / Slip Ring

[0051] 153 Line Channels

[0052] 154 Bearing / Seal

[0053] 155 Spring / Damper Element

[0054] 200 Water Surface

[0055] 300 Wave Energy Converter

[0056] 400 Mooring Line

[0057] 500 Electrical Conductor

[0058] 600 Fluid Conduit

[0059] 700 Mooring Anchor

Claims

1. A swivel-based mooring device for a marine energy device, the device comprising:a housing configured for placement along a primary mooring line of a marine energy device;a slip ring disposed within the housing and configured to transmit electrical power through the mooring device while permitting relative rotational motion between an upper portion and a lower portion of the mooring device;a rotary union swivel joint disposed within the housing and configured to transmit fluid through the mooring device while permitting relative rotational motion between the upper portion and the lower portion of the mooring device;wherein the slip ring and the rotary union swivel joint are coaxially arranged to allow continuous rotation of electrical conductors and fluid lines through at least 360 degrees about a longitudinal axis of the mooring device;an integrated spring damper mechanism positioned within the housing and operatively coupled to the electrical conductors and the fluid lines;wherein the integrated spring damper mechanism is configured to absorb axial loads applied to the electrical conductors and the fluid lines without absorbing mechanical energy from the marine energy device; andwherein the swivel-based mooring device is configured to reduce twisting, fatigue, and axial loading of the electrical conductors and the fluid lines during operation.

2. The swivel-based mooring device of claim 1, wherein the slip ring comprises a multi-channel electrical slip ring configured to transmit three-phase electrical power and control signals between the marine energy device and an external power distribution system.

3. The swivel-based mooring device of claim 1, wherein the rotary union swivel joint comprises a sealed fluid rotary union configured to transmit pressurized desalinated water from the marine energy device to an external fluid conduit.

4. The swivel-based mooring device of claim 1, wherein the integrated spring damper mechanism comprises a compression spring arranged in series with the electrical conductors and the fluid lines to accommodate axial displacement caused by wave-induced motion.

5. The swivel-based mooring device of claim 1, wherein the housing is configured to be installed inline with a single primary mooring line such that the swivel-based mooring device supports both electrical transmission and fluid transmission without requiring a secondary anchor.

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