Marine craft for transporting heavy or voluminous objects to and from deep submergence

Abstract

A method of and apparatus for transporting heavy or voluminous objects to and from shallow or deep submergence including providing a plurality of elongated handling columns (21) detachably connectable to spaced connectors on the cargo (15); providing at least one control device enabling control of the plurality of elongated handling columns; Connecting at least one towing device (41) Use of cargo as part of marine vessel; Requirement to only tow back part of the marine vessel after leaving cargo (15) in location and in particular towing back plurality of elongated handling columns (21) when detachably disconnected from the cargo. Thereby in a first mode, the towing device (41) is able to tow the elongated handling columns (21) when attached to the cargo (15) and in a second mode the control of the plurality of elongated handling columns allows controlled movement by the control device engaging with a towing vessel to manoeuvre the cargo container in the required submerged position.

Description

Marine craft for transporting heavy or voluminous objects to and from deep submergence

[0001] Field of the Invention

[0002] The present invention relates to a marine craft for transporting heavy or voluminous objects to and from shallow or deep submergence and despite significant time-varying loads due to wave, current and wind.

[0003] Throughout this document “to and from shallow or deep submergence” means between land and underwater or subsea locations or between different underwater locations and includes between port berth and predetermined seabed locations.

[0004] The invention has been developed primarily for use in / with container cargo and will be described hereinafter with reference to this application. However, it will be appreciated that the invention is not limited to this particular field of use.

[0005] Throughout this document “container” or “cargo” includes purpose-built modules or reconfigured shipping containers or the like.

[0006] This invention is also aimed at contributing to unlocking submerged lands for purposes of infrastructural development in ways that are currently not feasible. One such example of submerged land infrastructural development would be large-scale, repeatable and relatively inexpensively reversible modular construction at in-shore locations adjacent to congested coastal cities. At present, development of offshore oil and gas facilities by way of subsea lifting in remote, relatively calm and deeply submerged seabed locations represents the cutting edge of modular infrastructural development of submerged lands, though subsea lifting is a medium-scale and an exceptionally expensive enterprise.

[0007] Background of the Invention

[0008] There has never been a need for back-and-forth access between ports and seabed locations for very large and heavy objects. However, emerging sectors of the maritime industry and some existing sectors would stand to gain significantly if this were to become reality. It is possible to achieve this by developing a new type ofmarine craft that uses its large cargo fulfilling some of the basic functional requirements of a marine craft, expanding the definition of “ship” and revolutionising marine construction.

[0009] Every time a wholly new type of industrial marine craft has been developed, a new sector of the maritime industry has come of age by taking advantage of its unique capabilities, also creating other new areas of activity. Perhaps the Mobile Offshore Drilling Unit is the most obvious example of this because drilling in deep and treacherous waters, and subsequently Offshore Oil and Gas, did not exist before its development. There are other examples too; Jack-ups, Ice-Breakers, Submarines, etc. and despite distinctiveness of their defining features, one of their commonalities is that once the corresponding need or enterprise opportunity presented itself, the new type of craft was born and the industry revolutionised in at least one way.

[0010] Providing reliable back-and-forth access between ports and seabed locations for very heavy and large objects is a new maritime enterprise opportunity. Ability to industrialise such an enterprise could have broad cost-saving applications in various existing and emerging sectors of the maritime industry; some of which are Offshore Oil and Gas and Marine Construction together with Marine Renewable Energies and Seabed Mining respectively. Currently, objects no heavier than a few hundred tonnes are routinely installed at pre-determined seabed locations (excluding structures sufficiently tall to reach bottom while piercing the water surface). In cases of Seabed Mining and Offshore Oil and Gas, processing and market delivery of the produced materials is finalised using an expensive combination of surface assets, in the form of platforms or floating vessels, with subsea pipelines. Some extreme examples of each of these elements include: a) Nearly 5,500 tonnes of topsides – atop 45,000 tonnes of bottom-supported structure at Bullwinkle Offshore Platform – has towered 529m above the seabed in waters more than 400m deep, since 1996; b) Nearly 900km long Ichthys subsea pipeline – delivering gas from a production facility at the offshore field to Darwin in Australia for processing and export – was made in 2015 using 700,000 tonnes of steel and 550,000 tonnes of concrete coating to make it sufficiently heavy to resist dislodgment by environmental forces;c) More than 20,000 tonnes of steel – for Nautilus Mineral’s 227m long Production Support Vessel to receive, process, store and offload seabed mining material onto market-bound Bulk Carriers – is intended to float above a seabed mine with only thrusters to keep it from drifting in any weather condition at the site4; and d) Prelude Floating Liquefied Natural Gas facility – the world’s largest floating man-made structure using 260,000 tonnes of steel to receive, process, liquefy, store and offload LNG onto market-bound Tankers – is permanently moored in cyclone-prone waters around 250m deep, since August 2017.

[0011] Various subsea electro-hydraulic and mechanical equipment such as well- heads, manifolds, Remotely Operated Vehicles, etc. have operated commercially for decades and the automation industry continues to replace direct human intervention in industrial settings. Assuming all-subsea facilities could be operated and if a new type of marine craft, better described as a system, could be designed to facilitate reliable back-and-forth access between ports and seabed locations for very heavy and large objects, the maritime industry, and by extension society, could benefit significantly.

[0012] The applicant aims to introduce this new type of industrial marine craft

[0013] It can be seen that known prior art marine craft for transporting heavy or voluminous objects to and from deep submergence has the problems of: a) Being large marine craft in order to handle large cargo b) Not being versatile c) Not optimizing energy and mass movement d) Being overly complex and cumbersome handling solutions e) Not allowing simpler equipment return after transport f) Requiring precision results that is only useable for precise limited uses. g) Need to consider small waterplane area so transportable in non- calm water

[0014] The present invention seeks to Marine craft for transporting heavy or voluminous objects to and from submergence, which will overcome or substantially ameliorate at least one or more of the deficiencies of the prior art, or to at least provide an alternative.

[0015] It is to be understood that, if any prior art information is referred to herein, such reference does not constitute an admission that the information forms part of the common general knowledge in the art, in Australia or any other country.

[0016] Summary of the Invention

[0017] According to the present invention there is provided a marine craft for transporting heavy or voluminous objects as cargo to and from submergence comprising a plurality of elongated handling columns detachably connectable to spaced connectors on the cargo.

[0018] The marine craft for transporting heavy or voluminous objects as cargo to and from submergence can comprise a plurality of elongated handling columns detachably connectable to spaced connectors on the cargo, at least one control device enabling control of the plurality of elongated handling columns, at least one towing connection device for allowing effective connection of a towing vessel to the cargo and / or at least one elongated handling columns, wherein towing connection to the cargo allows substantial towing movement and the connection to the elongated handling columns when attached to the cargo allows fine controlled movement of the cargo.

[0019] The cargo is self-contained and the plurality of elongated handling columns can include an interactive ballast for assisting submersion and emersion of the cargo to and from the submergence.

[0020] At least one control device enables control of the plurality of elongated handling columns. At least one towing connection device allows effective connection of a towing vessel to at least one elongated handling columns. In this way the elongated handling columns when attached to the cargo allows control movement by the control device engaging with a towing vessel.

[0021] The marine craft can be for transporting to and from submergence including between port berth and a predetermined seabed location.

[0022] Preferably there is an effective by a framework interconnecting with the plurality of elongated handling

[0023] The plurality of elongated handling columns each includes a powered drive to allow coordinated assistance to towing and positioning of the cargo despite time- varying disturbances caused by environmental forces acting upon the craft and cargo. Each of the plurality of elongated handling columns each includes a powered drive to allow coordinated assistance to transporting the cargo in a submerged state. Powering can be by an electrically driven azimuth thruster or can be a water-jet.

[0024] The cargo and the plurality of elongated handling columns each includes a ballast compartment to allow controlled raising or lowering in a submerged state of the cargo. The cargo ballast compartment is adapted to provide controlled ballasting and de-ballasting capability powered by hydraulic pumps onboard each elongated handling column and connected to an inbuilt hydraulic circuit.

[0025] The at least one towing connection device connecting to the plurality of elongated handling columns includes direct or indirect connection to towing chains or tow wire with piggy-backing electrical cabling having connection terminals.

[0026] The marine craft can be fitted with a robotic arm to plug and / or unplug hydraulic adaptor into cargo receptacles.

[0027] In a form of the invention there is provided a handling column, for use in combination to form a marine craft. Each handling column has an elongated body for use in a submerged state in a substantially vertical orientation; the elongated body having at an upper end a protruding mast for assisting vertical orientation in submerged state and allowing for connection to a towing connection and towing vessel and at a lower end one or more connectors for connecting to spaced connectors of a cargo. A motor is positioned between the upper end and the lower end and in use orientable to effect movement in a horizontal plane and protected by an apron having circumference greater than the vertical circumference of the motor.

[0028] The protruding masts of a plurality of handling columns are receivable in a framework to maintain the plurality of handling columns in fixed special configuration and in parallel vertical orientation wherein they form a single marine craft for connection and transporting of connected cargo to and from a required submerged location.

[0029] The one or more connectors able to spread out to connect to spaced locations on the cargo container and strength of connection.

[0030] Preferably the one or more connectors are connectable to larger versions of “elephant feet” used as universal connectors on shipping containers. Handling column connection points can lock into the cargo.

[0031] Also the invention provides a method of transporting heavy or voluminous objects to and from shallow or deep submergence including the steps of: a) Providing a plurality of elongated handling columns detachably connectable to spaced connectors on the cargo; b) Providing at least one control device enabling control of the plurality of elongated handling columns; c) Connecting at least one towing device for allowing display of an output to each of the plurality; d) Use of cargo as part of marine vessel e) Requirement to only tow back part of the marine vessel after leaving cargo in location. f) In particular towing back plurality of elongated handling columns when detachably disconnected from the cargo. Thereby in a first mode, the towing device is able to tow the elongated handling columns when attached to the cargo and in a second mode the control of the plurality of elongated handling columns allows controlled movement by the control device engaging with a towing vessel to manoeuvre the cargo container in the required submerged position.

[0032] Manoeuvring of the cargo can includes one or more of: i) Controlled towing of cargo in a floating arrangement by connection to towing device ii) Controlled submerged lateral movement of the cargo container to or from the lateral position of the required submerged location by the plurality of elongated handling columns.iii) Raising or lowering the cargo or from the vertical position of the required submerged location by the of elongated handling columns and the controlled ballast iv) Controlled submerged vertical movement of the cargo container to or from the required submerged location by the plurality of elongated handling columns.

[0033] A towing vessel is preferably fitted with a purpose-built machine to do / undo piggy-backing of electrical cabling onto its Tow Wire as well as electrical generation required to power handling columns. Also, the towing vessel can be fitted with towing winch with motion compensation ability and a piggy-backing machine

[0034] The system can include a suspending module which includes a plurality of main winches fitted with passive heave compensation and pulley systems, wherein the winches and pulley systems are connected to a plurality of the elongated handling columns which can be detachably connectable to spaced connectors on the cargo container to enable controlled lowering or raising of the submerged spaced connectors and the cargo container by the suspending module floating on the water surface.

[0035] The suspending module is fitted with towing winch with motion compensation ability and a piggy backing machine.

[0036] The passive heave compensation uses an adjustable stiffness pneumatic spring-damper system as a shock-absorber fitted to the tow tug or suspending module to limit considerable wave-induced motions at the time of lifting.

[0037] It can be seen that the handling columns ballasting system, as well as thrusters working together in dynamic positioning mode to counter wind, current and waves, position handling columns connection points at cargo connection points. Handling column connection points lock into cargo and each handling columns has a robotic arm to work to establish hydraulic connection by exposing Hot Stab Receptacles before inserting Hot Stabs.

[0038] The invention in its various forms provides one or a combination of one or more of the following benefits of: ^ improvements in structure and assembly including construction in order to minimise equipment needed to transport large cargo^ Improvements in versatility ^ Improvements in drive and control of large cargo to and from shallow or deep submergence.

[0039] Some concepts used in various combinations are: 1) Deconstructed concept of offshore construction vessel 2) Relies on cargo and other craft 3) Long distance relies on tug to get to location 4) Navigation and control able to be undertaken by master on tug with common controls 5) Buoyancy includes relies on cargo buoyancy and active ballast 6) Configuration provides a small water plane area 7) Accuracy of Steerage in a controlled manner and with reduced effects due to configuration allows install of very large cargo in high energy waters and very close to each other

[0040] The system unlike the prior art does not require the cargo to be dismantled and returned in pieces but instead can be reinstated in movable format with handling columns to be transported back to shore in a complete format.

[0041]

[0042]

[0043] Brief Description of the Drawings

[0044] Notwithstanding any other forms which may fall within the scope of the present invention, preferred embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which: Fig. 1 is a diagrammatic view of a marine craft for transporting heavy or voluminous objects as cargo to and from submergence with handling columns in accordance with a preferred embodiment of the present invention that can be used with towing vessel to move cargo to and from a submergence; Fig 2 is a diagrammatic view of the effect of small waterplane area on different shaped bodies in the water; Fig 3 is a diagrammatic view of use of shock absorption and passive heave compensation to aid control of movement in non-calm waters; Fig.4 is a diagrammatic view of a handling column in accordance with a preferred embodiment of the present invention that can be used with cargo and towing vessel to move cargo to and from a submergence; andFigs.5 and 6 are diagrammatic of lightweight and heavyweight frameworks that can provide shallow collar or deep submergence collar respectively for connecting multiple handling columns of Fig 4 to provide a marine craft with the cargo in accordance with another preferred embodiment of the present invention; Figs 7 and 8 are diagrammatic views of use of a plurality of handling columns such as shown in Fig 4 for transporting cargo to submergence and allowing return only of handling columns in accordance with another preferred embodiment of the present invention; Figs 9 and 10 are diagrammatic views of use of a plurality of handling columns such as shown in Fig 4 with lightweight framework of Fig 5 for transporting cargo to submergence and allowing return only of handling columns and lightweight framework in accordance with another preferred embodiment of the present invention; Figs 11, 12 and 13 are diagrammatic views of use of a plurality of handling columns such as shown in Fig 4 with heavyweight framework of Fig 6 together with a suspending vehicle of Fig 17 for transporting cargo to submergence and suspending to deep submergence by the suspending vehicle and allowing return only of handling columns and heavy weight framework and suspending vehicle in accordance with another preferred embodiment of the present Figs 14 and 15 are diagrammatic views of use of a plurality of handling columns such as shown in Fig 4 with heavyweight framework of Fig 6 and suspending vehicle of Fig 17 for transporting cargo to deep submergence and allowing return only of handling columns and heavyweight framework in accordance with another preferred embodiment of the present invention; Fig 16 is a diagrammatic view of a towing vehicle usable to tow the marine craft of the invention Fig 17 is a diagrammatic view of a suspending vehicle usable to suspend cargo in deep submergence in accordance with the invention. Fig 18 is a diagrammatic flow diagram of methods of undertaking transport of heavy or voluminous objects as cargo to and from shallow or deep submergence in accordance with the invention.

[0045] Description of Preferred

[0046] It should be noted in the following description that like or the same reference numerals in different embodiments denote the same or similar features.

[0047] Referring to the drawings there is shown a marine craft for transporting heavy or voluminous objects as cargo to and from submergence.

[0048] A plurality of elongated handling columns 21 detachably connectable to spaced connectors on the cargo 15 with at least one control device enabling control of the plurality of elongated handling columns.

[0049] There is at least one towing connection device of tow lines 42, or lightweight or heavyweight framework for shallow or deep submergence collar 31, 36 respectively and for allowing effective connection of a towing vessel 41 to at least one elongated handling columns 21 wherein the elongated handling columns when attached to the cargo allows controlled movement by the control device engaging with a towing vessel.

[0050] The marine craft 11 is then able to transport the cargo 15 to and from submergence including between port berth and a predetermined seabed location.

[0051] System Components a) CARGO b) HANDLING COLUMN c) BALLASTING d) PIERCING WATER SURFACE e) SHOCK ABSORPTION AND PASSIVE HEAVE COMPENSATION f) SHALLOW-SUBMERGENCE COLLAR g) DEEP-SUBMERGENCE COLLAR h) TOW UMBILICAL i) TOW VESSEL j) SUSPENDING MODULE

[0052] A. - CARGO

[0053] The cargo 15 is generally a massive and voluminous object (e.g. Figure 7 and 9) with at least the following defining features: ^ Its mass is roughly equal to its volume multiplied by density of water; ^ Receives and releases connection with handling columns 21 such as through “handling feet”. Connection points to handling columns can be in the form of “Elephant Feet” already in universal use for securing shipping containers to ships and together. ^ Hot stab into cargo to create connection. Hot Stabs and Receptacles underwater to power hydraulic tools, transfer fluid, perform chemical injections, and to monitor hydraulic system pressure ^ Hydraulic circuitry in cargo to receive controls ^ Controlled ballasting and de-ballasting capability powered by hydraulic pumps connected to an inbuilt hydraulic circuit.

[0054] B. - HANDLING COLUMN

[0055] The handling column 21 is a floating steel structures (e.g. Figure 4) with at least the following defining features: a) Elongated top cylindrical body 23 which is slender, especially at the top and connects at the bottom to a frustoconical collar 24; b) By the height of the Elongated top cylindrical body 23, attachment to the load and elongation and protrusion out of the water to minimize waterplane area effect, it provides a stabilizing effect of the load 15 so it can be transported in non-calm waters. c) Fitted with an electrically driven azimuth thruster 27 sitting below the frustoconical collar 24 and within protective struts 25, the thruster 27 is able to be activated and coordinated with other handling columns 21 to provide fine tune horizontal location of the load to precisely submerge in location and to aid safe retrieval; d) Fitted with devices to connect to cargo connection points in the form of “Elephant Feet” already in universal use for securing shipping containers to ships and together. The points of connection 28 match the elephant feet. e) By its modularity of a plurality of handling columns and connectability to variouspreviously defined connection points on load 15, the system can be scaled to the particular load size, volume and f) Controlled ballasting and de-ballasting is available including in the lower chamber 26 that can include hydraulic, control systems and ballast systems or can interact with a ballast chamber 22 in the load (as shown in Fig.1; g) Fitted with electrically driven hydraulic pump and manifold to energise cargo ballasting system; h) Fitted with a robotic arm 29 to plug / unplug hydraulic adaptor into / from cargo hot-stab receptacles; i) Fitted with towing chains 42 piggy-backing electrical cabling with connection terminals to enable connection to towingvesseland other handling columns; and

[0056] A preferred range of azipod / waterjet power rating is 26kW to 8MW for azipods and 100kw to 6.4MW for waterjets per a Thrust Master of Texas Inc. or with an ABB providing 75kWto 7.5MWazipods as well. It can be seen that devices with moderate power are capable ofprecise handling when devisedin this configuration.

[0057] C. - BALLASTING

[0058] In a calculation of ballast for a particular load of a rectangular prism cargo and that 4 Handling Columns 21 of a certain type are required where there is:

[0059]

[0060] 14

[0061] MakeFraction ofΔ contributed ParameterDescriptionMin.Max.C Thaelcfuollalotwioinngs:underlined values can be used in conjunction with Tables 1, 3 and 4 to determine ballast amounts: Cargo's ∇ (m3) = L∙W∙H = 23625.0 HCs' ∇ (m3) = QTcB∙π / 4∙∑(D2∙Hsub.) = 931.5 Cargo's Δ (t) = ∇Cargo∙ρw = 24215.6 HCs' Δ (t) = ∇HCs∙ρw = 954.8

[0064] Table 3: Sum of cargo's permanent and adjustable ballast as a function of lightship and payload PBT+ABT as PDT as Fraction of Δ 50.15 0.80 0.75 0.70 0.60 0.55 0.50 0.45 0.40 0.35 0.300.20 0.75 0.70 0.65 0.55 0.50 0.45 0.40 0.35 0.30 0.25 025 070 065 060 055 050 045 040 035 030 025 020 50 5ABT as LDT as Fraction of Δ Fraction of Δ 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50 0.55 0.60 0.65 5 0 5 0 5

[0066] D. - PIERCING WATER SURFACE

[0067] Referring to Fig 2 there is shown the waterplane area on various shaped articles. This includes a usual large barge which has a waterplane area of its entire horizontal cross section. Therefore, this maximum perimetral amount and maximum volume interacts with the non-calm seas and is unstable. The AW(or waterplane area) forms a maximum baseline. Even when such barge has a central opening it still has maximum perimeter and maximum volume. The AW is still similar to the baseline without the central opening. In semi submersibles having openings between vertical structures there is a small waterplane AW. However the

[0068] The tether 55 to the handling columns is under tension to give vertical restraint. However, piercing the water surface by the handling column is important. As is shown in Fig 2 when the different shapes pierce the water there are different waterplane areas as shown by horizontal cross-sections.

[0069] The smaller the ratio of waterplane area to total weight of a floating object, the less forcefully the object is moved about by the passing waves. That is the smaller the waterplane area, the smaller compared to volume submerged so that there is effective less movement out of control. Overall, the transported weight is “less lively” and more readily towable even in non-calm waters.

[0070] It can be seen that the use of an elongated vertical cylinder of the SPAR or handling column 21 is the most effective approach.

[0071] Another limiting factor on the column is its height. This needs to be at least equal to the water depth at time of or construction plus consideration of the elevation of the biggest water to be encountered. Therefore handling columns need to be taller to cater for high seas in the North Sea but could be shorter in calmer waters in Sydney Harbour. Also, the depth of the cargo is a consideration of the handling column height.

[0072] (i) Shallow Submergence

[0073] In shallow submergence version, therefore the handling columns attached to the load must always protrude above the water for stability. Therefore the size of the handling column for a particular load at a particular shallow submergence the handling column height is: HC height ≥ (depth of water + average size of waves) - load height.

[0074] In this way, with the handling columns attached to the top of the load there is a combined marine craft integral with the load and with selective multiples of handling columns that can be stable even in rough waters due to the handling columns piercing the top of the water and effecting stability.

[0075] (ii) Deep Submergence

[0076] In deep submergence version, as shown in Figs 11, 12, 13, 14 and 15, the suspending cable or tether 55 is kept under relatively little tension and breaks the water surface. The same benefits of a small waterplane area achieved by the shallow submergence version are replicated by the combination of the handling columns 21 and passively heave-compensated tethers 55 despite much larger waterplane area of suspending module 51. The load suspended from the suspending module 51 is ballasted to be negatively buoyant to only a slight extent and passive heave compensation is pre-tuned so as to limit the tension in the tethers 55 despite significant wave action.

[0077] E. - SHOCK ABSORPTION AND PASSIVE HEAVE COMPENSATION

[0078] Particularly for this deep submergence, shock absorbing units are the solution for passive shock absorption and reduction of dynamic forces in offshore lifting operations. They are spring-damper units based on cylinders and accumulators. Whena piston rod is extended, hydraulic fluid through orifices, causing a floating piston to compress gas. The spring effect is by the compressed gas, while the dampening effect is caused by restricted flow through the orifices. Key parameters are: ^ Max possible extension of the piston rod (max stroke) ^ Spring stiffness (The force versus stroke characteristics) ^ Dampening characteristics (different for in- and out stroke) ^ The dampening and stiffness characteristics are optimized for each operation by setting the hydraulic fluid volume and gas pressure. ^ A typical unit has a safe working load (SWL) of 150 Tonne (Te) and a 4500 mm stroke range. The main application areas are splash zone crossing as well as passive heave compensation and resonance elimination at deep and shallow water. It is also well suited for transfer lifts, subsea retrieval and overload protection.

[0079] F. - SHALLOW-SUBMERGENCE COLLAR

[0080] The shallow submergence collar 31 is a watertight and stiffened steel frame 32(e.g. Figure 5) made from modular components and made extra stiff without significantly increasing self-weight by post-tensioning with Kevlar strands 34.

[0081] They are with locking ring mechanisms 33 to enable rigid connection with and disconnection from handling columns 21. They are also fitted with cabling and connection terminals to enable electrical connectivity between handling columns;

[0082] G. - DEEP-SUBMERGENCE COLLAR

[0083] The heavy duty framework acts as a deep submergence collar 36 which is a watertight and stiffened steel frame (e.g. Figure 6) made from modular components. They fitted with a) braces and locking mechanisms to enable rigid connection / disconnection to / from handling columns b) cabling and connection terminals to enable electrical connectivity between handling columns;c) trussed receptacles to receive tow rigging for re-routing purposes;

[0084] Optionally, they are fitted with fold-out horizontal fins to increase vertical added mass in water; and made extra stiff without significantly increasing self-weight by post- tensioning with Kevlar strands

[0085] H. - TOW UMBILICAL

[0086] The tow umbilical 42 has Electrical and communications cabling piggy-backed onto towing vessel’s Tow Wire or towing chain to convey electrical current without being subjected to tensile strain. The piggy-backing has to be done / undone after / before wire / chain is wound on / off a winch drum, which can be performed by a machine fitted to the towing vessel’s back deck.

[0087] An alternative to piggy-backing electrical and communications cabling onto towing vessel’s Tow Wire or towing chain 42 is using a constant tension winch arrangement to run the cabling independently of the Tow Wire. Such an arrangement is necessary to create electrical and communications link between Suspending Module and handling columns.

[0088] Another alternative to piggy-packing electrical and communications cabling onto towing vessel’s Tow Wire is to replace it with a Tow Wire with these cabling built into its core, somewhat similar to overhead high-voltage transmission lines except with insulation at the core, not on the exterior. ore, not on the exterior.

[0089] I. - TOW VESSEL

[0090] Referring to Fig 16, the primary towing vessel 41 used is a tow tug which can be an existing Anchor Handling Tug (AHT) having tow winch 43 connected to tow lines 42 through tow pins 46 at rear of vessel. Electrical generation and cabling storage 44 is on deck. It is also fitted with a purpose-built machine 45 to do / undo piggy-backing of electrical cabling onto its Tow Wire 42 as well as electrical generation and piggy back connections required to power handling columns 21.

[0091] J. - SUSPENDING MODULE

[0092] The suspending module 51 is a barge-shaped steel ship (e.g. Figure 17) with electrically powered azimuth thrusters; electrical generators; fuel storage. There are adjustable trussed outriggers 57 with fairleads for feeding the tethers 55 to the top of the submerged handling columns connected to the load 15.

[0093] Four main winches 53, 58 can fitted with Passive Heave Compensation (handling column) and pulley systems; towing winch 53 can include motion compensation ability and a Piggy-Backing machine 54 similar to that of towing vessel 41.

[0094] The system is fitted with towing chains piggy-backing electrical cabling with connection terminals to enable connection to towing vessel; fitted with stern roller box 56 and tugger winches 58 for handling of Tow wire 55 on back deck; and have a knuckle-boom crane 52 atop a central bridge, which can be used to move the boom outriggers 57 up and down as required. Trussed outrigger with fairleads is able to be raised / boomed up while not under load to facilitate transiting as well as connection / disconnection of winch wires to and from the handling columns 21.

[0095] Passive Heave Compensation is achieved with adjustable stiffness pneumatic spring-damper system used in offshore engineering as a shock-absorber during lifting of large and / or heavy objects by a crane fitted to a ship with considerable wave- induced motions at the time of lifting.

[0096] In use

[0097] In option 1 the cargo is built, assembled and / or prepared on Slipway; handling columns are fitted to cargo by crane and all connections are made; cargo is launched in the same way as a ship would be launched; and towing vessel is connected to handling columns’ pre-fitted Tow Bridle by way of Tow Wire, ready to sail away.

[0098] In option 2 the cargo is built, assembled and / or prepared quay-side on stands; handling columns are fitted to cargo by crane and all connections are made; cargo is put onto a Floating-Dock or Synchro-Lift using SPMTs or Skidded Load-Out method; Floating-Dock / SynchroLift is submerged to float cargo off; and towing vessel is connected to handling columns’ pre-fitted tow bridle by way of Tow Wire, ready to sail away.

[0099] In option 3 the cargo is built, assembled and / or prepared in a Dry-Dock; handling columns are fitted to cargo by crane and all connections are made; Dry-Dock is flooded; and towing vessel is connected to handling columns’ pre-fitted tow bridle by way of Tow Wire, ready to sail away.

[0100] Transportation of cargo Destination on Seabed or Underwater is achieved by cargo being towed to site by towing vessel 41 in the same way a barge would be towed by a tug at sea; and handling column thrusters are used to assist if and when necessary.

[0101] However the cargo can be propelled to installation / delivery site by handling column thrusters; and towing vessel provides electrical power only (small towing vessels can be used for short journeys).

[0102] Lowering cargo onto Position on Seabed or Underwater is achieved Once cargo arrives at its position, handling column thrusters are used in Dynamic Positioning mode to hold station against actions of wind, current and waves; Ballasting operations within handling columns and / or cargo result in controlled lowering of cargo onto its position on the seabed or underwater; and Hydraulic motors within handling columns are used to actuate any necessary operations to secure cargo in position, including flooding of compartments or clamping foundations.

[0103] Leaving cargo in Position at Sea and Returning SDS to Port includes the handling columns’ robotic arms retrieving hydraulic Hot Stabs and, if cargo is intended for future recovery, cover receptacles to prevent corrosion and marine growth; handling columns are ballasted / deballasted to ensure tension at connection points to cargo is conducive to release of connections and immediate raising of each handling column upon disconnection from the cargo; One leg of tow bridle is remotely released from its connection to a handling column; handling columns are all remotely disconnected from the cargo; towing vessel tows handling columns back to port where they are lifted out of the water by crane for maintenance / reuse; and towing vessel is demobilised as required.

[0104] Example of How to Use shallow submergence recovery system (SRC)

[0105] Handling columns are assembled quay-side; SC is fitted to handling columns by crane and all mechanical / electrical connections are made; handling columns and SC are out onto Floating- Dock / Synchro-Lift using Suspending ModulePTs for lowering into water or lifted into water by quayside crane or crane barge; and towing vessel is connected to handling columns’ pre-fitted tow bridle by way of Tow Wire, ready to sail away.

[0106] In another form handling are assembled on Slipway; SC is fitted to handling columns by crane and all connections are made; handling columns and SC are launched / pulled into water; and towing vessel is connected to handling columns’ pre-fitted Tow Bridle by way of Tow Wire, ready to sail away.

[0107] Transporting shallow submergence recovery system (SRS) to cargo Location has handling columns and SC are towed to cargo location by towing vessel in the same way a barge would be towed by a tug at sea; and handling column thrusters are used to assist if and when necessary. Alternatively handling columns and SC are propelled to cargo by handling column thrusters; and towing vessel provides electrical power only (small towing vessels can be used for short journeys).

[0108] Installing shallow submergence recovery system (SRS) onto cargo on Seabed or Underwater Position is by handling columns’ ballasting system, as well as thrusters working together in Dynamic Positioning mode to counter wind, current and waves, position handling columns’ connection points at cargo’s connection points; and handling columns’ connection points lock into cargo and handling columns’ robotic arms work to establish hydraulic connection by exposing Hot Stab Receptacles before inserting Hot Stabs.

[0109] Cargo has to have been fitted with receptacle guides in the form of funnels at connection points to handling columns. Also, handling columns have to have been fitted with small waterjets to blow these connection points clean of sand / sediment and excess marine growth before / during the process of locking handling columns into cargo. Ensuring such a process performs well and with sufficient reliably is a matter of applying existing best practices in subsea engineering and incorporation of redundancy. As an example, connection points on cargo could be designed in such a way that upon release of handling columns at the time of installation, they are filled with sand by adjacent reservoirs incorporated for this purpose, preventing any marine growth from forming.

[0110] Raising cargo from seabed or underwater positon is by hydraulic pumps on handling columns are used to operate hydraulic circuits intended for preparing cargo before raising from seabed (e.g. releasing foundation clamps); cargo de- ballasting system is operated to ultimately raise cargo from seabed or underwaterposition; and After raising cargo from seabed, vertical position of cargo in water is adjusted for transportation to port by ballasting / de-ballasting cargo and / or handling columns.

[0111] Transporting cargo to Port is by cargo is towed to port by towing vessel in the same way a barge would be towed by a tug at sea; and handling column thrusters are used to assist if and when necessary. However cargo can be propelled to port by handling column thrusters; and towing vessel provides electrical power only (small towing vessels can be used for short journeys).

[0112] Recovering cargo to land and demobilising shallow submergence recovery system (SRS) is in one form achieved with a. cargo is positioned at bottom of Slipway using a combination of its ballasting system, handling columns’ ballasting systems, handling columns’ thrusters working together in Dynamic Positioning mode and mooring facilities available at the Slipway; b. towing vessel is demobilised; cargo is pulled ashore using winches or strand-jacks; SC is lifted away after all connections handling columns are undone; handling columns are lifted away by crane after all connections to cargo are undone; handling columns and SC are demobilised; and cargo is used and / or worked upon as intended.

[0113] In another form cargo is positioned on submerged deck of Floating- Dock / Synchro-Lift using a suitable combination of its ballasting system, handling columns’ ballasting systems and handling columns thrusters working together in Dynamic Positioning mode and mooring facilities available aboard Floating- Dock / Synchro-Lift; b. towing vessel is demobilised; cargo is lifted out of water by Floating-Dock / Synchro-Lift; cargo is transported from Floating-Dock / Synchro-Lift to a suitable location on land using SPMTs or Skidded Load-Out method; e. SC is lifted away after all connections handling columns are undone; handling columns are lifted away by crane after all connections to cargo are undone; handling columns and SC are demobilised; and cargo is used and / or worked upon as intended.

[0114] In still a further form a. cargo is positioned at bottom of flooded Dry-Dock using a combination of its ballasting system, handling columns’ ballasting systems, handling columns’ thrusters working together in Dynamic Positioning mode and mooring facilities available at the Dry-Dock; b. towing vessel is demobilised; Dry-Dock is closed and all water is pumped out to expose cargo; SC is lifted away after allconnections handling columns are handling columns are lifted away by crane after all connections to cargo are handling columns and SC are demobilised; and cargo is used and / or worked upon as intended.

[0115] Example of How to Use DEEP-SUBMERGENCE DELIVERY SYSTEM

[0116] Cargo is built, assembled and / or prepared on Slipway; handling columns and Deep Submergence Collar are fitted to cargo by crane and all connections are made; cargo is launched in the same way as a ship would be launched; Suspending Module is connected to handling columns’ pre-fitted Tow Bridle by way of Tow Wire; and towing vessel is connected to Suspending Module’s pre-fitted Tow Bridle by way of Tow Wire, ready to sail away.

[0117] In another form the cargo is built, assembled and / or prepared quay-side on stands; handling columns and Deep Submergence Collar are fitted to cargo by crane and all connections are made; cargo is put onto a Floating-Dock or Synchro-Lift using SPMTs or Skidded Load-Out method; Floating-Dock / SynchroLift is submerged to float cargo off; Suspending Module is connected to handling columns’ pre-fitted Tow Bridle by way of Tow Wire; and towing vessel is connected to Suspending Module’s pre-fitted Tow Bridle by way of Tow Wire, ready to sail away.

[0118] Still further cargo is built, assembled and / or prepared in a Dry-Dock; handling columns and Deep Submergence Collar are fitted to cargo by crane and all connections are made; Dry-Dock is flooded; Suspending Module is connected to handling columns’ pre-fitted Tow Bridle by way of Tow Wire; and towing vessel is connected to Suspending Module’s pre-fitted Tow Bridle by way of Tow Wire, ready to sail away.

[0119] Transportation of cargo to Destination on Seabed or Underwater is achieved by cargo and Suspending Module are towed to installation / delivery site by Suspending Module and Towing Vessel in the same way a barge would be towed by a tug at sea; and hydraulic column / Suspending Module thrusters are used to assist if and when necessary.

[0120] In another form cargo / Suspending Module is propelled to installation / delivery site by hydraulic column / Suspending Module thrusters; and Towing Vessel provides electrical power or emergency response capability only (small Towing Vessels can be used for short journeys).

[0121] It is also feasible to utilise Towing Vessels for very large cargos; Towing Vessels could be connected separately as well as in opposing configuration if needed.

[0122] Preparing to Lower cargo onto Position on Seabed or Underwater is undertaken by Once cargo arrives at its position, hydraulic column and Suspending Module thrusters are used in Dynamic Positioning mode to hold station against actions of wind, current and waves; Suspending Module’s TU winch is operated in constant tension mode; Ballasting operations within hydraulic columns, Deep Submergence Collar and / or cargo result in controlled lowering of cargo to a position where moving it under Suspending Module will not result in a clash between hydraulic columns and Suspending Module outriggers in raised configuration; hydraulic column and Suspending Module thrusters are used to position the cargo under the Suspending Module and hold station; Hoisting wires from Suspending Module winches, routed through outriggers, are connected to top of hydraulic columns; and Suspending Module outriggers are put into operational configuration (only configuration shown graphically in this document).

[0123] TU between Suspending Module and hydraulic columns is secured into the receptacle on Deep Submergence Collar during positioning of cargo under Suspending Module. Also, wave induced motions of Suspending Module and cargo will need to be accommodated by a sufficiently large vertical airgap between top of hydraulic columns and bottom of Suspending Module outriggers, as well as horizontal clearance between Suspending Module and hydraulic columns.

[0124] Lowering cargo onto Position on Seabed or Underwater is undertaken Once cargo is prepared for lowering, hydraulic column and Suspending Module thrusters are continued to be used in Dynamic Positioning mode to hold station against actions of wind, current and waves; Ballasting operations within hydraulic columns and / or cargo, together with operation of passively heave-compensated hoisting winches and operation of TU winch in constant tension mode, result in controlled lowering of cargo onto its position on the seabed or underwater; After touch-down, Suspending Module’s passively heave compensated hoisting winches are set to low stiffness mode; and Hydraulic motors within hydraulic columns are used to actuate any necessary operations to secure cargo in position, including flooding ofcompartments or clamping foundations.

[0125] Once cargo is prepared for lowering, hydraulic column and Suspending Module thrusters are continued to be used in Dynamic Positioning mode to hold station against actions of wind, current and waves; Ballasting operations within hydraulic columns and / or cargo, together with operation of passively heave-compensated hoisting winches and operation of TU winch in constant tension mode, result in controlled lowering of cargo onto its position on the seabed or underwater, with ties installed between Suspending Module’s TU and adjacent hoisting wires as required to present clashing between these parts; After touch-down, Suspending Module’s passively heave compensated hoisting winches are set to low stiffness mode; and Hydraulic motors within hydraulic columns are used to actuate any necessary operations to secure cargo in position, including flooding of compartments or clamping foundations.

[0126] Any cargo with integrated foundation system would be placed directly onto the seabed. Otherwise, cargo would be placed onto foundations previously constructed. Foundation construction may be carried out using purpose-built cargo that would be removed from site upon completion of its tasks. Also, fold-out fins could be optionally incorporated into Deep Submergence Collar to increase it horizontal projected area at time of disconnection from cargo, reducing hydraulic column and Deep Submergence Collar motions induced by fluctuations in tension within hoisting wires due to Suspending Module’s wave-induced motions.

[0127] Leaving cargo in Position at Sea and Returning DDS to Port is achieved by hydraulic columns’ robotic arms retrieve hydraulic Hot Stabs and, if cargo is intended for future recovery, cover receptacles to prevent corrosion and marine growth; hydraulic columns and / or Deep Submergence Collar are ballasted / de- ballasted, together with paying out wire on Suspending Module’s passively heave- compensated winches and TU winch, to ensure level of compression at connection points to cargo is conducive to release of these connections without any immediately resulting movements of hydraulic columns;

[0128] Hydraulic columns and / or Deep Submergence Collar are deballasted, together with paying in of wire on Suspending Module’s passively heave compensated winches and TU winch, to raise hydraulic columns and Deep Submergence Collar tosurface where hydraulic column and Module thrusters are used to position hydraulic columns and Deep Collar under the Suspending Module and hold station; Suspending Module’s outriggers are raised from load bearing position and hoisting wires are disconnected from top of hydraulic columns; hydraulic columns and Deep Submergence Collar are moved astern of Suspending Module while Suspending Module’s TU is released from Deep Submergence Collar’s receptacle; hydraulic columns and / or Deep Submergence Collar are deballasted to suit tow; Towing Vessel tows Suspending Module and Suspending Module in turn tows hydraulic columns back to port; Deep Submergence Collar and hydraulic columns are slipped or lifted out of the water by crane for maintenance / reuse; and Suspending Module and Towing Vessel are demobilised as required.

[0129] Example of How to Use DEEP-SUBMERGENCE RECOVERY SYSTEM

[0130] Hydraulic columns are assembled quay-side; Deep Submergence Collar is fitted to hydraulic columns by crane and all mechanical / electrical connections are made; hydraulic columns and Deep Submergence Collar are out onto Floating- Dock / Synchro-Lift using Suspending ModulePTs for lowering into water or lifted into water by quayside crane or crane barge; Suspending Module is connected to hydraulic columns’ pre-fitted Tow Bridle by way of Tow Wire; and Towing Vessel is connected to Suspending Module’s pre-fitted tow bridle by way of Tow Wire, ready to sail away.

[0131] Alternatively hydraulic columns are assembled on Slipway; Deep Submergence Collar is fitted to hydraulic columns by crane and all mechanical / electrical connections are made; hydraulic columns and Deep Submergence Collar are launched / pulled into water; Suspending Module is connected to hydraulic columns’ pre-fitted Tow Bridle by way of Tow Wire; and Towing Vessel is connected to hydraulic columns’ pre-fitted Tow Bridle by way of Tow Wire, ready to sail away.

[0132] Other options are also feasible from a technical standpoint; however, economic feasibility is generally limited to the options presented due to scarcity of DryDocks and the relatively lightweight nature of the Shallow Water Recovery System compared to ships of similar overall dimensions, making lifting / lowering / launching more attractive.

[0133] Transporting DRS to cargo Location includes hydraulic columns, DeepSubmergence Collar and are towed to cargo location by Suspending Module and Towing the same way a barge would be towed by a tug at sea; and hydraulic column / Suspending Module thrusters are used to assist if and when necessary.

[0134] Hydraulic columns, Deep Submergence Collar and Suspending Module are propelled to cargo by hydraulic column and Suspending Module thrusters; and Towing Vessel provides electrical power only (small Towing Vessels can be used for short journeys).

[0135] It is also feasible to utilise multiple Towing Vessels for very large DRSs; Towing Vessels could be connected in tandem, separately as well as in opposing configuration if needed.

[0136] Preparing to Lower DRS onto cargo on Seabed or Underwater Position comprises Once hydraulic columns, Deep Submergence Collar and Suspending Module arrive at cargo’s position, hydraulic column and Suspending Module thrusters are used in Dynamic Positioning mode to hold station against actions of wind, current and waves; Suspending Module’s TU winch is switched to operate in constant tension mode; Ballasting operations within hydraulic columns and / or Deep Submergence Collar result in controlled lowering of hydraulic columns and Deep Submergence Collar to a position where moving them under Suspending Module will not result in a clash between hydraulic columns and Suspending Module outriggers in raised configuration; hydraulic column and Suspending Module thrusters are used to position the hydraulic columns and Deep Submergence Collar under Suspending Module and hold station; Hoisting wires from Suspending Module winches, routed through outriggers, are connected to top of hydraulic columns; and Suspending Module outriggers are put into operational configuration (only configuration shown graphically in this document).

[0137] TU between Suspending Module and hydraulic columns is secured into the receptacle on Deep Submergence Collar during positioning of hydraulic columns and Deep Submergence Collar under Suspending Module. Also, wave induced motions of Suspending Module and cargo will need to be accommodated by a sufficiently large vertical airgap between top of hydraulic columns and bottom of Suspending Module outriggers, as well as horizontal clearance between SuspendingModule and hydraulic columns.

[0138] Installing DRS onto cargo on Seabed or Underwater Position includes hydraulic columns’ and / or Deep Submergence Collar’s ballasting system, together with Suspending Module’s passively heave compensated hoisting winches (in low stiffness mode) and TU winch in constant tension mode, as well as Suspending Module’s and hydraulic columns’ thrusters working together in Dynamic Positioning mode to counter wind, current and waves, position hydraulic columns’ connection points at cargo’s connection points; and hydraulic columns’ connection points lock into cargo and hydraulic columns’ robotic arms work to establish hydraulic connection by exposing Hot Stab Receptacles before inserting Hot Stabs.

[0139] Hydraulic columns’ and / or Deep Submergence Collar’s ballasting system, together with Suspending Module’s passively heave compensated hoisting winches (in low-stiffness mode) and TU winch in constant tension mode, as well as Suspending Module’s and hydraulic columns’ thrusters working together in Dynamic Positioning mode to counter wind, current and waves, position hydraulic columns’ connection points at cargo’s connection points, with ties being installed between Suspending Module’s TU and adjacent hoisting wires as required to present clashing between these parts; and hydraulic columns’ connection points lock into cargo and hydraulic columns’ robotic arms work to establish hydraulic connection by exposing Hot Stab Receptacles before inserting Hot Stabs.

[0140] Cargo has to have been fitted with receptacle guides in the form of funnels at connection points to hydraulic columns. Also, hydraulic columns have to have been fitted with small waterjets to blow these connection points clean of sand / sediment and excess marine growth before / during the process of locking hydraulic columns into cargo. Ensuring such a process performs well and with sufficient reliably is a matter of applying existing best practices in subsea engineering and incorporation of redundancy. As an example, connection points on cargo could be designed in such a way that upon release of hydraulic columns at the time of installation, they are filled with sand by adjacent reservoirs incorporated for this purpose, preventing any marine growth from forming.

[0141] Raising cargo from Seabed or Underwater Position has Hydraulic pumps on hydraulic columns used to operate hydraulic circuits intended for preparing cargobefore raising from seabed (e.g. foundation clamps); cargo’s, hydraulic column’s and / or Deep Submergence de-ballasting systems are operated to ultimately raise cargo from seabed or underwater position to surface with assistance from Suspending Module’s passively heave-compensated winches in normal stiffness mode, while Suspending Module’s TU winch continues to operate in constant tension mode; and During and raising cargo to surface, hydraulic column and Suspending Module thrusters are used to horizontally position the cargo under the Suspending Module and hold station.

[0142] Cargo has to be purpose-designed to ensure reliably at the time of rising after being in-situ underwater for a long period of time. Also, once cargo is raised to surface, wave induced motions of Suspending Module and cargo will need to be accommodated by a sufficiently large vertical airgap between top of hydraulic columns and bottom of Suspending Module outriggers, as well as horizontal clearance between Suspending Module and hydraulic columns.

[0143] Transporting cargo to Port uses Suspending Module’s outriggers are raised from load bearing position and hoisting wires are disconnected from top of hydraulic columns; cargo is moved astern of Suspending Module while Suspending Module’s TU is released from Deep Submergence Collar’s receptacle; cargo, hydraulic columns and / or Deep Submergence Collar are de-ballasted to suit tow; cargo and Suspending Module are towed to port by Suspending Module and Towing Vessel in the same way a barge would be towed by a tug at sea; and hydraulic column / Suspending Module thrusters are used to assist if and when necessary.

[0144] Alternatively Suspending Module’s outriggers are raised from load bearing position and hoisting wires are disconnected from top of hydraulic columns; cargo is moved astern of Suspending Module while Suspending Module’s TU is released from Deep Submergence Collar’s receptacle; cargo, hydraulic columns and / or Deep Submergence Collar are de-ballasted to suit tow; cargo / Suspending Module is propelled to port by hydraulic column / Suspending Module thrusters; and Towing Vessel provides electrical power or emergency response capability only (small Towing Vessels can be used for short journeys).

[0145] It is also feasible to utilise multiple Towing Vessels for very large cargos; Towing Vessels could be connected in tandem, separately as well as in opposingconfiguration if needed.

[0146] Recovering cargo to Land and Demobilising DRS under option 1 has a) cargo is positioned at bottom of Slipway using a combination of its ballasting system, hydraulic columns’ ballasting systems, hydraulic columns’ thrusters working together in Dynamic Positioning mode and mooring facilities available at the Slipway; b) Suspending Module and Towing Vessel are demobilised; c) cargo is pulled ashore using winches or strand-jacks; d) Deep Submergence Collar is lifted away after all connections hydraulic columns are undone; e) hydraulic columns are lifted away by crane after all connections to cargo are undone; f) hydraulic columns and Deep Submergence Collar are demobilised; and g) cargo is used and / or worked upon as intended.

[0147] In option 2 a) cargo is positioned on submerged deck of Floating-Dock / Synchro-Lift using a suitable combination of its ballasting system, hydraulic columns’ ballasting systems and hydraulic columns thrusters working together in Dynamic Positioning mode and mooring facilities available aboard Floating-Dock / Synchro-Lift; b) Suspending Module and Towing Vessel are demobilised; c) cargo is lifted out of water by Floating-Dock / Synchro-Lift; d) cargo is transported from Floating-Dock / Synchro-Lift to a suitable location on land using SPMTs or Skidded Load-Out method; e) Deep Submergence Collar is lifted away after all connections hydraulic columns are undone; f) hydraulic columns are lifted away by crane after all connections to cargo are undone; g) hydraulic columns and Deep Submergence Collar are demobilised; and h) cargo is used and / or worked upon as intended.

[0148] In option 3 a) cargo is positioned at bottom of flooded Dry-Dock using a combination of its ballasting system, hydraulic columns’ ballasting systems, hydraulic columns’ thrusters working together in Dynamic Positioning mode and mooring facilities available at the Dry-Dock; b) Suspending Module and Towing Vessel are demobilised; c) Dry-Dock is closed and all water is pumped out to expose cargo; d) Deep Submergence Collar is lifted away after all connections hydraulic columns are undone; e) hydraulic columns are lifted away by crane after all connections to cargo are undone; f) hydraulic columns and Deep Submergence Collar are demobilised; and g) cargo is used and / or worked upon as intended.

[0149] Other options are also feasible depending on mass, volume and de- ballasting capability of cargo together with availability of port infrastructure (e.g. large gantry cranes) cargo could be redeployed or recycled depending on its enterprise.

[0150] Differences

[0151] Key points of difference between wet-towing and Deep-Submergence Delivery System (DDS) as well as with Shallow-Submergence Delivery System (SDS) are explored.

[0152] A summary of these key points of difference is provided below:

[0153] 1. Wet-towing is a method of only transporting a cargo; however, DDS and SDS would both be methods of transport as well as of accurate, predictable and highly repeatable installation ^, by using thrusters attached to CARGO to counter with actions of waves and current;

[0154] 2. Unlike DDS and SDS, methods of installation that could follow a wet- tow afford little ability to counter effect of waves and / or current on the horizontal position of the CARGO; and

[0155] 3. Unlike DDS and SDS, towing does not provide a high degree of manoeuvrability, requiring much and rigorous contingency planning to mitigate the risk of being unable, due to weather conditions at sea, to hold course, or station. Table 3-1: Comparative performance of Qualitative Performance conventional and proposed technology Parameter to ) 0 ed

[0156] Other novel features include Reversibility. Prior systems do not have anything pertaining to transporting to and from submergence including between port berth and a predetermined seabed location or concerned with any total reversibility ofa cargo from a seabed installation at after the first or subsequent instances of installation.

[0157] It was found in the early 1970s that although very large reinforced concrete structures could be constructed underwater in-situ (so as to circumvent the impossibility of installing them due to their great size and weight), their feasibility was severely limited because they could never be repaired in-situ for common concrete defects that were inevitable to occur. Recalling that such structures were simply too large and heavy to be installed in the first place, it is clear that they could also not be removed for repairs or reinstalled after repairs.

[0158] Total reversibility of a cargo's seabed installation at any time is a substantial benefit provided by the system of the present invention. That is, because not only is it intertwined with at least a few fundamental and unparalleled design features of the invention, it also means cargoes can be recovered and redeployed multiple times with relative ease, unlike D1's or D2's cargoes. Such easy reversibility of cargoes' seabed installation allows previously unfeasible projects to proceed.

[0159] Other benefits provided by the invention will be understood by persons skilled in the art ands are included within the scope of this invention.

[0160] Interpretation Embodiments:

[0161] Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment, but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments.

[0162] Similarly, it should be appreciated that in the above description of example embodiments of the invention, various features of the invention aresometimes grouped together in a figure, or description thereof for the purpose of streamlining the and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the Detailed Description of Specific Embodiments are hereby expressly incorporated into this Detailed Description of Specific Embodiments, with each claim standing on its own as a separate embodiment of this invention.

[0163] Furthermore, while some embodiments described herein include some but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form different embodiments, as would be understood by those in the art. For example, in the following claims, any of the claimed embodiments can be used in any combination. Different Instances of Objects

[0164] As used herein, unless otherwise specified the use of the ordinal adjectives “first”, “second”, “third”, etc., to describe a common object, merely indicate that different instances of like objects are being referred to, and are not intended to imply that the objects so described must be in a given sequence, either temporally, spatially, in ranking, or in any other manner. Specific Details

[0165] In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the invention may be practiced without these specific details. In other instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description. Terminology

[0166] In describing the preferred embodiment of the invention illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, theinvention is not intended to be limited specific terms so selected, and it is to be understood that each specific term all technical equivalents which operate in a similar manner to accomplish a similar technical purpose. Terms such as "forward", "rearward", "radially", "peripherally", "upwardly", "downwardly", and the like are used as words of convenience to provide reference points and are not to be construed as limiting terms. Comprising and Including

[0167] In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” are used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

[0168] Any one of the terms: including or which includes or that includes as used herein is also an open term that also means including at least the elements / features that follow the term, but not excluding others. Thus, including is synonymous with and means comprising. Scope of Invention

[0169] Thus, while there has been described what are believed to be the preferred embodiments of the invention, those skilled in the art will recognize that other and further modifications may be made thereto without departing from the spirit of the invention, and it is intended to claim all such changes and modifications as fall within the scope of the invention. For example, any formulas given above are merely representative of procedures that may be used. Functionality may be added or deleted from the block diagrams and operations may be interchanged among functional blocks. Steps may be added or deleted to methods described within the scope of the present invention.

[0170] Although the invention been described with reference to specific examples, it will be appreciated by skilled in the art that the invention may be embodied in many other forms.

[0171] Definitions Nomenclature Description Abbreviationto connect to disconnect from cargo (Section 4.2).TOW UMBILICAL To be TU T Wir St l ir r nd nt min inh f TW

[0172] Industrial Applicability

[0173] It is apparent from the above, that the arrangements described are applicable to the marine cargo, marine construction and marine transport industries.

Claims

[00174] Claims The claims defining the invention are as follows:

1. A marine craft for transporting heavy or voluminous objects as cargo to and from a submergence location comprising a. a plurality of elongated handling columns each having i. a connector detachably connectable to spaced connectors on a self-contained cargo to allow each handling column to submerge and ascend with the self-contained cargo; ii. a controllable ballast allowing for controlling the handling column to effect depth control of the self-contained cargo; iii. a controllable powered drive for controlling the handling column to effect lateral control of the self-contained cargo b. At least one control device enabling simultaneous control of a matrix of the plurality of elongated handling columns connected to the self- contained cargo; c. At least one towing connection device for allowing effective connection of a towing vessel to the cargo and / or at least one elongated handling columns wherein towing connection to the cargo allows substantial towing movement to the general required location d. and wherein the connection to the elongated handling columns when attached to the cargo and control of each respective ballast and each respective powered drives control fine controlled movement of the cargo to the submergence location e. and wherein the connection to the elongated handling columns when attached to the cargo and control of each respective ballast and each respective powered drives control fine controlled movement of the cargo from the submergence location.

2. A marine craft according to claim 1 wherein each handling column, includes a. An elongated body for use in a submerged state in a substantially vertical orientation; the elongated body having: i. At an upper end a protruding mast for assisting vertical orientation in submerged state and allowing for connection to a towing connection and towing vesselii. At a lower end one more connectors for connecting to spaced connectors of a cargo b. A motor positioned between the upper end and the lower end and in use orientatable to effect movement in a horizontal plane and protected by an apron having circumference greater than the vertical circumference of the motor.

3. A marine craft according to claim 2 wherein the protruding masts of a plurality of handling columns are receivable in a framework to maintain the plurality of handling columns a. In fixed special configuration b. In parallel vertical orientation wherein they form a single marine craft for connection and transporting of connected cargo to and from a required submerged location.

4. A marine craft according to claim 3 wherein the one or more connectors are able to spread out to connect to spaced locations on the cargo container and increase strength of connection.

5. A marine craft according to claim 4 wherein the handling column has the one or more connectors which are connectable to larger versions of “elephant feet” used as universal connectors on shipping containers.

6. A marine craft according to claim 5 wherein the wherein handling column connection points lock into the cargo.

7. A marine craft according to claim 1 wherein the effective connection of a towing vessel to at least one elongated handling columns is to allow towing of the at least one elongated handling columns.

8. A marine craft according to claim 1 wherein the effective connection of a towing vessel to at least one elongated handling columns is to allow control of towing of the at least one elongated handling columns.

9. A marine craft according to claim 1 wherein the effective connection of a towing vessel to at least one elongated handling columns is to allow towing of the cargo.

10. A marine craft according to claim the effective connection of a towing vessel to at least one columns is to allow control of the towing of the cargo.

11. A marine craft according to claim 1 for transporting to and from submergence including between port berth and a predetermined seabed location.

12. A marine craft according to claim 1 including effective connection by a framework interconnecting with the plurality of elongated handling columns.

13. A marine craft according to claim 1 wherein the plurality of elongated handling columns each includes a powered drive to allow coordinated assistance to transporting the cargo in a submerged state.

14. A marine craft according to claim 1 wherein the plurality of elongated handling columns each includes a powered drive to allow coordinated assistance to towing and positioning of the cargo despite time-varying disturbances caused by environmental forces acting upon the craft and cargo.

15. A marine craft according to claim 1 wherein the powered drive is an electrically driven azimuth thruster.

16. A marine craft according to claim 1 wherein the powered drive is a water-jet.

17. A marine craft according to claim 1 wherein the cargo and the plurality of elongated handling columns each includes a ballast compartment to allow controlled raising or lowering in a submerged state of the cargo.

18. A marine craft according to claim 1 wherein the cargo ballast compartment is adapted to provide controlled ballasting and de-ballasting capability powered by hydraulic pumps onboard each elongated handling column and connected to an inbuilt hydraulic circuit.

19. A marine craft according to claim 1 wherein the at least one towing connection device connecting to the plurality of elongated handling columns includes direct or indirect connection to towing chains or tow wire with piggy-backing electrical cabling having connection terminals.

20. A marine craft according to claim 1 fitted with a robotic arm to plug and / or unplug hydraulic adaptor into cargo receptacles.

21. A handling column, for use in to form a marine craft according to claim 1, including a. An elongated body for use in a submerged state in a substantially vertical orientation; the elongated body having: i. At an upper end a protruding mast for assisting vertical orientation in submerged state and allowing for connection to a towing connection and towing vessel ii. At a lower end one or more connectors for connecting to spaced connectors of a cargo b. A motor positioned between the upper end and the lower end and in use orientatable to effect movement in a horizontal plane and protected by an apron having circumference greater than the vertical circumference of the motor.

22. A handling column according to claim 21 wherein the protruding masts of a plurality of handling columns are receivable in a framework to maintain the plurality of handling columns a. In fixed special configuration b. In parallel vertical orientation wherein they form a single marine craft for connection and transporting of connected cargo to and from a required submerged location.

23. A handling column according to claim 21 wherein the one or more connectors are able to spread out to connect to spaced locations on the cargo container and increase strength of connection.

24. A handling column according to claim 23 wherein the one or more connectors are connectable to larger versions of “elephant feet” used as universal connectors on shipping containers.

25. A handling column according to claim 23 wherein handling column connection points lock into the cargo.

26. A method of transporting heavy or voluminous objects to and from shallow or deep submergence including the steps of:a. Providing a plurality handling columns detachably connectable to spaced connectors on the cargo; b. Providing at least one control device enabling control of the plurality of elongated handling columns; c. Connecting at least one towing device for allowing display of an output to each of the plurality; d. wherein i. in a first mode towing device is able to tow the elongated handling columns when attached to the cargo ii. in a second mode the control of the plurality of elongated handling columns allows controlled movement by the control device engaging with a towing vessel to manoeuvre the cargo container in the required submerged position.

27. A method of transporting heavy or voluminous objects to and from submergence according to claim 26 wherein manoeuvring of the cargo includes one or more of: a. Controlled submerged lateral movement of the cargo container to or from the lateral position of the required submerged location b. Raising or lowering the cargo to or from the vertical position of the required submerged location.

28. A method according to claim 26 or 27 wherein to and from submergence includes between port berth and accurately predetermined seabed locations.

29. A method according to claim 26 wherein a towing vessel is fitted with a purpose- built machine to do / undo piggy-backing of electrical cabling onto its Tow Wire as well as electrical generation required to power handling columns 30. A method according to claim 26 wherein a towing vessel is fitted with towing winch with motion compensation ability and a piggy-backing machine 31. A method according to claim 26 wherein a suspending module includes a plurality of main winches fitted with passive heave compensation and pulley systems, wherein the winches and pulley systems are connected to a pluralityof the elongated handling which can be detachably connectable to spaced connectors on the cargo to enable controlled lowering or raising of the submerged spaced connectors and the cargo container by the suspending module floating on the water surface.

32. A method according to claim 26 wherein a suspending module is fitted with towing winch with motion compensation ability and a piggy backing machine 33. A method according to claim 26 wherein passive heave compensation uses an adjustable stiffness pneumatic spring-damper system as a shock-absorber fitted to the tow tug or suspending module to limit considerable wave-induced motions at the time of lifting.

34. A method according to claim 26 wherein handling columns ballasting system, as well as thrusters working together in dynamic positioning mode to counter wind, current and waves, position handling columns connection points at cargo connection points.

35. A method according to claim 26 wherein handling column connection points lock into cargo and each handling columns has a robotic arm to work to establish hydraulic connection by exposing Hot Stab Receptacles before inserting Hot Stabs.

36. A marine craft for transporting heavy or voluminous objects as cargo to and from submergence comprising a. a plurality of elongated handling columns detachably connectable to spaced connectors on a self-contained cargo; b. At least one control device enabling control of the plurality of elongated handling columns; c. At least one towing connection device for allowing effective connection of a towing vessel to the cargo and / or at least one elongated handling columns; d. A controllable ballast associated with the cargo and / or the plurality of elongated handling columnse. wherein towing to the cargo allows substantial towing movement to the general location and the connection to the elongated handling columns when attached to the cargo and control of the ballast allows fine controlled movement of the cargo to the submergence location.

37. A marine craft according to claim 36 wherein the effective connection of a towing vessel to at least one elongated handling columns is to allow towing of the at least one elongated handling columns.

38. A marine craft according to claim 36 wherein the effective connection of a towing vessel to at least one elongated handling columns is to allow control of towing of the at least one elongated handling columns.

39. A marine craft according to claim 36 wherein the effective connection of a towing vessel to at least one elongated handling columns is to allow towing of the cargo.

40. A marine craft according to claim 36 wherein the effective connection of a towing vessel to at least one elongated handling columns is to allow control of the towing of the cargo.

41. A marine craft according to claim 36 for transporting to and from submergence including between port berth and a predetermined seabed location.

42. A marine craft according to claim 36 including effective connection by a framework interconnecting with the plurality of elongated handling columns.

43. A marine craft according to claim 36 wherein the plurality of elongated handling columns each includes a powered drive to allow coordinated assistance to transporting the cargo in a submerged state.

44. A marine craft according to claim 36 wherein the plurality of elongated handling columns each includes a powered drive to allow coordinated assistance to towing and positioning of the cargo despite time-varying disturbances caused by environmental forces acting upon the craft and cargo.

45. A marine craft according to claim 36 wherein the powered drive is an electrically driven azimuth thruster.

46. A marine craft according to wherein the powered drive is a water-jet.

47. A marine craft according to claim 36 wherein the cargo and the plurality of elongated handling columns each includes a ballast compartment to allow controlled raising or lowering in a submerged state of the cargo.

48. A marine craft according to claim 36 wherein the cargo ballast compartment is adapted to provide controlled ballasting and de-ballasting capability powered by hydraulic pumps onboard each elongated handling column and connected to an inbuilt hydraulic circuit.

49. A marine craft according to claim 36 wherein the at least one towing connection device connecting to the plurality of elongated handling columns includes direct or indirect connection to towing chains or tow wire with piggy-backing electrical cabling having connection terminals.

50. A marine craft according to claim 36 fitted with a robotic arm to plug and / or unplug hydraulic adaptor into cargo receptacles.

51. A handling column, for use in combination to form a marine craft according to claim 1, including a. An elongated body for use in a submerged state in a substantially vertical orientation; the elongated body having: i. At an upper end a protruding mast for assisting vertical orientation in submerged state and allowing for connection to a towing connection and towing vessel ii. At a lower end one or more connectors for connecting to spaced connectors of a cargo b. A motor positioned between the upper end and the lower end and in use orientatable to effect movement in a horizontal plane and protected by an apron having circumference greater than the vertical circumference of the motor.

52. A handling column according to claim 51 wherein the protruding masts of a plurality of handling columns are receivable in a framework to maintain the plurality of handling columnsa. In fixed special b. In parallel vertical orientation wherein they form a single marine craft for connection and transporting of connected cargo to and from a required submerged location.

53. A handling column according to claim 51 wherein the one or more connectors are able to spread out to connect to spaced locations on the cargo container and increase strength of connection.

54. A handling column according to claim 53 wherein the one or more connectors are connectable to larger versions of “elephant feet” used as universal connectors on shipping containers.

55. A handling column according to claim 53 wherein handling column connection points lock into the cargo.

56. A method of transporting heavy or voluminous objects to and from shallow or deep submergence including the steps of: a. Providing a plurality of elongated handling columns detachably connectable to spaced connectors on the cargo; b. Providing at least one control device enabling control of the plurality of elongated handling columns; c. Connecting at least one towing device for allowing display of an output to each of the plurality; d. wherein i. in a first mode towing device is able to tow the elongated handling columns when attached to the cargo ii. in a second mode the control of the plurality of elongated handling columns allows controlled movement by the control device engaging with a towing vessel to manoeuvre the cargo container in the required submerged position.

57. A method of transporting heavy or voluminous objects to and from submergence according to claim 51 wherein manoeuvring of the cargo includes one or more of:a. Controlled submerged movement of the cargo container to or from the lateral position of the submerged location b. Raising or lowering the cargo to or from the vertical position of the required submerged location.

58. A method according to claim 51 or 52 wherein to and from submergence includes between port berth and accurately predetermined seabed locations.

59. A method according to claim 51 wherein a towing vessel is fitted with a purpose- built machine to do / undo piggy-backing of electrical cabling onto its Tow Wire as well as electrical generation required to power handling columns 60. A method according to claim 51 wherein a towing vessel is fitted with towing winch with motion compensation ability and a piggy-backing machine 61. A method according to claim 51 wherein a suspending module includes a plurality of main winches fitted with passive heave compensation and pulley systems, wherein the winches and pulley systems are connected to a plurality of the elongated handling columns which can be detachably connectable to spaced connectors on the cargo container to enable controlled lowering or raising of the submerged spaced connectors and the cargo container by the suspending module floating on the water surface.

62. A method according to claim 51 wherein a suspending module is fitted with towing winch with motion compensation ability and a piggy backing machine 63. A method according to claim 51 wherein passive heave compensation uses an adjustable stiffness pneumatic spring-damper system as a shock-absorber fitted to the tow tug or suspending module to limit considerable wave-induced motions at the time of lifting.

64. A method according to claim 51 wherein handling columns ballasting system, as well as thrusters working together in dynamic positioning mode to counter wind, current and waves, position handling columns connection points at cargo connection points.

65. A method according to claim 51 wherein handling column connection points lock into cargo and each handling columns has a robotic arm to work toestablish hydraulic connection exposing Hot Stab Receptacles before inserting Hot Stabs.

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