BACKGROUND OF THE INVENTION : Currently, single hull marine vessels of adequate quality and seaworthiness that are approaching forced retirement age are being acquired and converted for special service applications in the offshore oil field development and construction industry. In the offshore oil field development industry, such vessels are converted into storage vessels or floating production storage and offloading vessels (FPSO's). In the construction industry, such vessels are converted into pipe-lay vessels, craneships or specialized lifting vessels. In both industries, the vessel conversion requires extensive and significant modifications to the existing or originally designed cargo systems and internal spaces.

In certain circumstances, the forebody or cargo carrying portions of the vessel are completely removed and disposed of as scrap. The remaining section with the propulsion plant is typically fitted to a new forebody and thereafter enters service as a new vessel. In other circumstances, original material handling systems, such as the piping and pumping systems, are totally or partially removed or rendered inoperably in

the conversion. Similar alterations are carried out to the internal spaces which significantly alter or destroy the original functionality.

Vessels which are not acquired or selected for conversion, but face forced retirement due to legislation or regulations (such as the requirement for double skinned hulls) are typically scrapped. A significant number of these vessels are of a high structural and operational quality, but for legislation or regulations, are being scrapped or at least forced out of the originally intended service.

Previous usages or conversions of existing marine vessels are disclosed in a number of references. A few exemplars are set forth below. U. S. Patent No.

3,919,960 issued to Amoss in 1975 discloses a ship and method of construction for converting two ships into a single wider hulled ship by utilizing a pair of juxtapositioned stern sections. More specifically, each stern section (with its own machinery) is joined to a common and wider forebody. This conversion transforms existing conventional vessels, which are economically obsolete because of their limited cargo carrying capacity, into vessels of increased load carrying and power capacities.

However, the disclosure does not contemplate exploitation of the existing payload characteristics and quality of the discarded forebodies.

U. S. Patent No. 5,899,162 issued to Beaupre et al. in 1999 discloses a tanker reconstruction method whereby a new outer hull is constructed around the existing hull to form a double hull vessel. This disclosure seeks to extend or at least maintain the usefulness of the original tanker and its cargo carrying capacity but at great cost and with an increase in the vessel's molded depth and molded beam. An increase

which may prohibit the converted vessel from transiting the Suez and/or Panama Canals.

In U. S. Patent No. 4,846,088 issued to Fanse et al. in 1989, an over-water compressed gas transport system having a storage vessel disposed on or above the deck of a vessel is disclosed. This disclosure contemplates only on or above deck storage and transportation of compressed gases in storage elements formed from standard oil field pipeline type pipes. A major drawback of this disclosure is the failure to: exploit the vessel's existing internal spaces and piping systems for the carriage of cargoes/ballast ; and extend the operational life of an existing vessel by allowing a variety of payloads to be carried above deck.

DISCLOSURE OF THE INVENTION : The present invention in its several disclosed embodiments alleviates the drawbacks described above with respect to conventional vessel conversions and the carriage of payloads on or above a deck. Furthermore the present invention as disclosed incorporates several additionally beneficial features further enhances the conversion and re-use of existing vessels.

The present invention generally contemplates a low-cost conversion and novel re-use of existing marine vessels by controlling and exploiting the buoyant force of the vessel's internal space to allow a substantial amount of a payload to be supported in a seaworthy manner above the main deck. Furthermore the present invention is intended to provide:

(a) a vessel fitted with an interface system to support, in a seaworthy manner, a substantial portion of a payload in a marine environment through the control and manipulation of the vessel's buoyant force and stability; (b) a novel conversion of an existing vessel by performing low-cost modifications which strengthen locally and globally the hull to support, in a seaworthy fashion, a payload in a marine environment; (c) a novel conversion of an existing vessel with at least one internal space by installing an interface system to support a payload above a deck and constructing at least one void in the hull to form a double skinned vessel to allow the carriage of valuable material in the at least one internal space; (d) a method for re-using a seaworthy vessel to support payloads above deck with an installed interface system and below deck carriage of valuable material with at least one existing internal space (like a cargo tank or hold) and at least one existing material handling system (like a liquid cargo piping/pumping system or crane); (e) a method for re-classifying a vessel to support, in a seaworthy fashion, a payload above and/or on a deck without significant changes (or modifications) to the functionality of the existing internal space (s) or the existing material handling system (s).

(f) a novel conversion of an existing vessel to carry, in a seaworthy fashion, loads above deck without significant changes to the functionality of the existing internal space (s) or the existing material handling system (s); and

(g) a novel low-cost method of decommissioning an existing vessel with at least one internal space from one service and commissioning it in another service which includes the transportation of a payload at and/or above a deck.

In general, the interface system is a network of structural members configured to support, in a seaworthy manner, a payload ; strengthen globally and locally the vessel's hull ; and transfer load forces to the vessel's hull. The payload support region of the interface system is adapted to receive a wide variety of permanently or removably fixed payloads, such as compressed natural gas storage modules (or containers), intermodal containers, extremely large bulky cargoes (like preassembled subsections of a refinery) or even seating, accommodations or a hotel. The foundation region of the interface system is configured to be permanently or removably fixed to the vessel. As can be appreciated, the payload support region (or a portion thereof) can be in a permanently fixed, removable fixed or moveable fixed relationship to the foundation region.

The beneficial effects described above apply generally to the exemplary devices and mechanisms disclosed herein. The specific structures and methods through which these benefits are delivered will be described in detail herein below.

BRIEF DESCRIPTION OF THE DRAWINGS : The invention will now be described in greater detail in the following way of example only and with reference to the attached drawings, in which: FIG. 1 A depicts a side view of an interface module fixed to a deck of a vessel with internal spaces supporting a compressed natural gas module payload.

FIG. 1 B is a cross sectional view through the vessel of FIG. 1 A.

FIG. 2A shows a side view of an interface module fixed to a deck of a vessel with a double hull supporting a compressed natural gas module payload above deck and supporting a fluid payload below deck.

FIG. 2B is a cross sectional view through the vessel of FIG. 2A.

FIG. 3A depicts a side view of an interface module fixed to a deck of a vessel with internal spaces supporting a payload of intermodal containers.

FIG. 3B is a cross sectional view through the vessel of FIG. 3A.

FIG. 4A shows a side view of an interface module fixed to a deck of a vessel with a double hull supporting a payload of intermodal containers above deck and supporting a fluid payload below deck.

FIG 4B is a cross sectional view through the vessel of FIG. 4A.

FIG. 5A depicts a side view of an interface module fixed to a deck of a vessel with internal spaces supporting a payload of continuous pipes wound in plural layers, each layer having plural loops.

FIG. 5B is a cross sectional view through the vessel of FIG. 5A.

FIG. 6A depicts a side view of an interface module fixed to a deck of a vessel with a double hull supporting a payload of continuous pipes wound in plural layers, each layer having plural loops above deck and supporting a fluid payload below deck.

FIG. 6B is a cross sectional view through the vessel of FIG. 6A.

MODE (S) FOR CARRYING OUT THE INVENTION : As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale, some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention.

Referring to the drawings in general but Figs. 1 A & B, 3 A & B and 5 A & B in particular, a vessel 10 fitted with an interface system 30 supporting a payload 40 above a deck 20 is shown. The vessel 10 depicted has at least one internal space 50 adapted to receive material (not shown) and accessible by at least one material handling system (not shown). As can be appreciated, most vessels 10 will have more than one internal space 50.

As described above, the interface system 30 may be configured to receive and support, in a seaworthy manner, a compressed natural gas (CNG) module 42 (Fig. 1 A & B), an intermodal container 44 (Fig. 3 A & B), a CNG coselle 46 (Fig. 5 A & B) and/or accommodations (not shown). In each of these embodiments, the internal space 50 may take the form of a liquid petroleum cargo tank, a liquid cargo tank, ballast tank, bulk cargo hold or a combination thereof as found in ore/bulk/oil (OBO) vessels.

In each of these embodiments, the vessel 10 is limited to the carriage of material (like ballast) or cargo which does not require a double hull vessel.

In a preferred embodiment, the interface module 30 is securely attached to a single hull tanker converted into a double hull tanker (Fig 2 A & B, 4 A & B, 6 A & B).

The single hull tanker is converted to a double hull vessel 10 by creating a void 60 between the internal space 50 and the marine environment. In another embodiment, the interface module 30 is securing attached to an existing double hull vessel. In both embodiments, the internal space 50 retains its original functionality as a cargo hold or liquid tank. Likewise, the material handling system (s), if fitted, retain (s) its original functionality to convey material in or out of the internal space (s) 50. The internal space (s) 50 and void (s) 60 may be used to control the seaworthiness, buoyancy and/or stability of the double hull vessel 10.

In yet another embodiment, the interface system 30 is removably fixed to an existing vessel 10 in the form of a double hull bulk, ore or OBO type ship. In this embodiment, the internal space 50 is in the form of a hold or tank/hold adapted to receive material (not shown) in bulk form through a hatch (not shown). The material handling system, if fitted, is in the form of a mast and boom combination, crane, gantry crane or similar lifting apparatus. That portion of the interface system 30 which obstructs the functionality of the internal space (s) 50 is (are) further configured to be removable by the vessel's material handling system, if fitted, or a material handling system located off the vessel 10.

The interface system 30 is a network of structural members (not shown) configured to support, in a seaworthy manner, a payload 40; strengthen globally and locally the hull of a vessel 10; and transfer load forces (such as the payload weight and/or dynamic loading from the marine environment) to the hull of the vessel 10. The payload support region (not shown) of the interface system 30 is adapted to receive a wide variety of permanently or removably fixed payloads 40, such as compressed natural gas storage modules 42 and 46, intermodal containers 44, extremely large bulky cargoes (like preassembled subsections of a refinery) or even passenger accommodations (not shown). The foundation region (not shown) of the interface system 30 is configured to be permanently or removably fixed to the vessel 10. As can be appreciated, the payload support region (or a portion thereof) can be in a permanently fixed or moveable fixed relationship to the foundation region to encourage or promote the handling of the payload 40. For example, if the CNG module 42 is supported by a moveably fixed payload support region, then the payload support region can be tilted at one end to change or maintain the attitude of the CNG module independent of the vessel's trim or list.

In another embodiment, a plurality of substantially vertical stanchions (not shown) covers a significant portion of the deck 20. Each stanchion is securely fixed near one end to and extends away from the deck 20 to form the foundation region (not shown) of the interface system 30. The foundation region may also include bracing and/or web frames attached to a significant number of the stanchions to encourage a unitary foundation region.

A network of substantially co-planar interconnected longitudinal and transverse beams to form at least one payload region of the interface system 30. In one embodiment, at least one payload region is permanently fixed to the distal end of a significant number of stanchions. In another embodiment, at least one payload region is permanently fixed to a substantially mid-portion of a significant number of stanchions so that the distal ends extend above the substantially horizontal plane defined by the interconnected beams. In another embodiment, a significant portion of at least one payload region can be removably or slidably mounted to the foundation region at a number of predetermined planes which are substantially parallel to and above the deck 20. In another embodiment, a significant portion of at least one payload region can be removably or slidably mounted to the foundation region at an infinite number of planes which may or may not be substantially parallel to the deck 20. This ability to articulate about at least three degrees of freedom enhances the ability to accommodate and support irregular shaped payloads 40 or enhance cargo operations. The articulation described above allows for inclining the interface system 30 in relation to the deck 20. Where a slidable mounting is utilized, a preferred embodiment includes adequate articulation between critical interconnections of the elements which make up the interface system 30 thereby eliminating or at least significantly reducing binding forces upon the interface system 30. Removable and/or slidable mounting may be achieved with securing pins and receivers arrangements; rack and pinion assemblies and/or jacking screw mechanisms.

The lower portion of the interface system 30 is fixed to the vessel 10 and adapted to transfer forces from the interface system 30 to the vessel 10 via stanchions pads (not shown) and/or deck inserts (not shown).

As can be appreciated by one skilled in the art, the vessel 10 may be a self- propelled marine vessel or a marine vessel adapted to be moved by a self-propelled vessel. Furthermore, it will be apparent to one skilled in the art that modifications may be made to the illustrated embodiments without departing from the spirit and scope of the invention as hereinafter defined in the claims.

INDUSTRIAL APPLICABILITY The present invention finds particular applicability in the marine transportation industries, but may be utilized in any marine environment in which an existing vessel can be modified and re-used to support a payload above a deck in a marine environment.