Patent Application
20230415861
The present invention is concerned with means for reducing fluid flow through a hole in a hull structure of a marine vessel or in a storage tank. Specifically, the invention is concerned with a novel salvage bag, a portable salvage system and a method of using the portable salvage system.
Holes in a hull structure of a marine vessel or in a storage tank may occur due to collisions, due to constructional failures, due to impact from a projectile or an explosion or simply due to material fatigue. A marine vessel, such as a ship or a floating structure, may, for instance, collide with another vessel, with a fixed structure or with nearshore rocks. In each case, a hole below or at the waterline may occur, allowing water to flow freely into the marine vessel, thereby threatening the floating capability of the vessel.
A storage tank for fluid or granular materials, such as a tank on a transport vehicle or a land-based tank, may similarly experience damage resulting in a hole in a wall of the storage tank. The fluid or granular contents of the storage tank may, consequently, freely flow out of the tank and into the outside environment, causing loss of the stored material and possibly, environmental damage or personal injuries.
Emergency salvaging equipment for reducing flow through a hole in a marine vessel or in a storage tank is known in the art. The purpose of such emergency salvaging equipment is to reduce or stop the inflow of water into a marine vessel or the outflow of fluid or granular material from a damaged storage tank. Such emergency salvaging equipment usually comprises a set of wood- or polymer-based plugs of different sizes, together with a hammering implement, such as a brass hammer. In use, an operator or a damage control crew selects a plug with an appropriate diameter and hammers the plug into the hole. The plug, if inserted properly, may stop, or partially stop, the flow through the hole. In marine environments, reducing the flow through the hole by 70% is considered a successful result.
A disadvantage of the known wood- or polymer-based plugs is that a large set with different plug diameters is required, in order to handle holes of different sizes. Such a large set of plugs is both heavy and voluminous, having a negative impact on handling and on storage requirements. Especially during, for instance, a post-collision emergency, cumbersome handling may critically slow down the emergency salvaging operation. Another disadvantage is that significant force is required to hammer the wood- or polymer-based plug into the hole. Such force is required as the hole is likely to have an irregular geometry, not matching that of the plug. Furthermore, force is required to insert the plug against the fluid or granular material pressure acting opposite to the direction of insertion of the plug. Especially for larger holes this may mean that several persons are required to perform the emergency salvaging operation, in order to hold the plug in-place and when hammering. A further disadvantage is that, due to a likely irregular geometry of the hole, the wood- or polymer-based plug may never be completely form-fittingly inserted into the hole. Consequently, the hole is not satisfactorily closed-off and the flow through the hole may not be reduced sufficiently.
Consequently, there is a clear need for an improved emergency salvaging means, which is portable, having a small weight and volume, which allows for improved handling, also in an emergency situation and when handled by a single operator, and which has an improved ability to reliably reduce the flow through holes of different sizes and geometries in a hull structure of a damaged marine vessel or in a storage tank.
The present invention concerns an inflatable salvage bag according to claim 1. The present invention also concerns a portable salvage system according to claim 13. Finally, the present invention also concerns the use of a salvage system according to claim 16 and a method for producing an inflatable salvage bag according to claim 17.
The inflatable salvage bag, the portable salvage system and use of the portable salvage system according to the present invention are applicable to marine vessels and to storage tanks. Advantageously, the inflatable salvage bag and portable salvage system of the present invention are easy to handle, require less force to apply than conventional systems and provide improved capacity for reducing fluid flow through a hole in a hull structure. A further advantage is that the speed of deployment of the portable salvage system of the present invention is significantly increased as compared conventional systems.
The outer surface of the inflatable salvage bag 1 is formed by an outer bag 2. In the deflated state, the outer bag 2 may have a generally rectangular shape, with a transversal leading side 3 and a transversal trailing side 4 and two longitudinal sides extending from the transversal trailing side 4 to the transversal leading side 3. Other shapes may also be possible for the outer bag 2 in the deflated state, such as an oval, triangular or multisided shape. The dimension of the inflatable salvage bag 1 along the trailing side 4, may be up to about 150 cm, preferably up to 100 cm, most preferably up to about 50 cm. The dimension of the inflatable salvage bag 1 along the longitudinal sides may range from about 20-150 cm, preferably from about 30-100 cm. The inflated volume of the inflatable salvage bag 1 is preferably less than about 2000 liters, more preferably less than about 500 liters, most preferably less than about 100 liters. Advantageously, portability of the portable salvage system, detailed below, in which the inflatable salvage bag is included is thereby maintained.
Protruding from the surface of the outer bag 2 is a valve 5. The valve 5 allows the inflatable salvage bag 1 to be inflated or deflated, as detailed below. One or more friction bands 6, detailed below, may be fixed onto the surface on one or either side of the outer bag 2. An elongated sleeve 7, detailed below, may optionally be fixed onto the surface of the outer bag 2. At the leading side 4, the outer bag 2 may optionally have a tapered shape. The tapered shape may facilitate easier insertion of the inflatable savage bag 1 into a hole in a hull structure, as detailed below. Finally, the outer bag 2 may be provided with an eyelet 8. The eyelet 8 may allow the inflatable salvage bag 1 to be releasably attached to an attachment line or clip, for attaching the inflatable salvage bag 1 to another element or to a fixed structure. The eyelet is preferably a plastic or metal ring, such as a D-ring, which may be attached to the outer bag 2 by means of a fabric attachment loop.
Surrounding the inner bag 9 is the reinforcing bag 10, as shown in
With further reference to
Referring to
Referring to
The valve 5 is schematically shown in a cross-section in
The inflatable salvage bag 1 may optionally be provided with a light source, not shown, such as a battery-operated light or a chemiluminescence-based glowstick. The light source may releasably be attached to the eyelet 8. By activating the light source, the inflatable salvage bag 1 can securely be used in a dark environment.
A method for producing an inflatable salvage bag 1 includes providing an inner bag 9, arranging a reinforcing bag 10 around the inner bag 9 and arranging an outer bag 2 around the reinforcing bag 10 to provide an initial bag and attaching a valve 5 to the initial bag. Arranging the reinforcing bag 10 around the inner bag 9 may include gluing, sewing, or welding the reinforcing bag 10 around the inner bag 9. Arranging the outer bag 2 around the reinforcing bag 10 may include gluing, sewing, or welding the outer bag 2 around the reinforcing bag 10. In each case, welding may include ultrasonic welding or heat welding. Attaching the valve 5 includes fitting the valve 5 through dedicated apertures in the inner bag 9, the reinforcing bag 10 and the outer bag 2 and attaching the valve 5 thereto.
A portable salvage system 16 is schematically shown in
The portable salvage system 16 includes one or more inflatable salvage bags 1, preferably two to ten inflatable salvage bags 1. For the sake of legibility only one inflatable salvage bag 1 is shown in
The portable salvage system may include a holding plate 17, serving as an organizing and handling element, from which each of the one or more inflatable salvage bags 1 may be suspended. Thereto, the portable salvage system 16 preferably includes one or more attachment lines 20. Each attachment line 20 may be provided with a quick-release clip at both ends thereof. Thereby, an inflatable salvage bag 1 may be quickly attached to, or released from, the holding plate 17. A quick release and attachment improve handling, for instance, when choosing the right inflatable salvage bag 1 during an emergency salvaging operation or when moving around the one or more inflatable salvage bags 1 at the emergency salvaging site.
The holding plate 17 includes one or more apertures 25 for attaching of one or more inflatable salvage bags 1 by means of attachment lines 20. The holding pate 17 also includes a central aperture 26, allowing an operator to grab the holding plate 17. The holding plate 17 further includes one or more apertures 27 for suspending the holding plate 17 from a fixed point. Such a suspension of the holding plate 17 may, for instance, be desirable when an operator needs to work hands-free during an emergency salvaging operation. The holding plate 17 preferably comprises a lightweight material of sufficient strength, such as a lightweight metal material or a reinforced polymer composite material.
The portable salvage system 16 includes a pressurized gas source 19, such as a tank, a cylinder or a canister, preferably a lightweight composite cylinder. The pressurized gas source 19 may have a volume of up to about 12 liters, preferably about 1-5 liters, most preferably about 3 liters. The gas comprised in the pressurized gas source 19 is preferably air or a mixture including air. When filled, the pressurized gas source 19 may comprise a pressurized gas with a pressure of about 100-300 bar, preferably about 200-300 bar, most preferably about 300 bar. The pressurized gas source 19 may, for example, have a volume of 3 liters and comprise pressurized air at 300 bars, equating to about 900 liters of air. The pressurized gas source 19 may be provided with carrying straps. Alternatively, the pressurized gas source 19 may be releasably held in the carrying bag, which may be a backpack. Advantageously, the pressurized gas source 19 can easily be carried on the back of an operator, thereby allowing the operator freedom of movement during an emergency salvaging operation.
The pressurized gas source 19 includes a valve 22, releasably attached to the pressurized gas source 19 and schematically shown in
The flexible tube 18 includes first and second connection pieces 21A and 21B, fixed at the opposite ends thereof. The first connection piece 21A is configured to form a releasable gas tight connection with the coupling 13 of the valve 5 on the inflatable salvage bag 1. The second connection piece 21B is configured to form a releasable gas tight connection with the coupling of the valve 22 of the pressurized gas source 19. The flexible tube 18 thereby allows the pressurized gas source 19 to be connected to an inflatable salvage bag 1. When not in use, the flexible tube 18 may remain connected to the valve 22 of the pressurized gas source 19 by means of the second connection piece 21B, with the first connection piece 21A of the flexible tube 18 remaining un-connected. The second connection piece 21B includes a second release lever 23, configured to open the inner passage of the flexible tube 18 to the outside environment. When the pressurized gas source 19 is connected to an inflatable salvage bag 1, the second release lever 23 can be operated to release pressurized gas from the inflatable salvage bag 1. Advantageously, the second release lever 23 may be activated by an operator positioned close to, or carrying, the pressurized gas source 19. Advantageously, the first release lever may be operated by another or the same operator, positioned close by the hole in a hull structure, in which the inflatable salvage bag 1 is inserted.
The portable salvage system 16 may further include a stiffening element. The stiffening element may comprise multiple sections and may preferably be collapsible, for ease of transportation and handling. At least one section is configured to be inserted into the elongated sleeve 7. The multiple sections may comprise telescoping tube-elements. The telescoping tube elements can manually be retracted or extended in a telescoping manner. The telescoping tube elements may comprise a locking mechanism, to prevent accidental collapse of the tube during use. The tube-element with the smallest diameter is configured to be inserted in the elongated sleeve 7. Alternatively, the multiple sections may be hinged sections, which can be unfolded to extend the stiffening element. The hinges may comprise a locking mechanism, to prevent accidental collapse of the stiffening element during use. Yet alternatively, the multiple sections may be connectable by screw connections, snap connections, or shock-cord connections. Advantageously, by utilizing a stiffening element, an operator may insert an inflatable salvage bag into a hole in a hull structure from a safe distance, thereby remaining out of reach from the flow through the hole. This is especially advantageous when the flow comprises a hazardous material.
Use of a portable salvage system 16 is detailed below. An inflatable salvage bag 1 is selected from the one or more inflatable salvage bags 1 in the portable salvage system 16. Preferably the selected inflatable salvage bag 1 matches or approximately matches the size of the hole in a hull structure.
Next, the inflatable salvage bag 1 is inserted into the hole. During insertion, the leading side 3 of the inflatable salvage bag 1 is passed through the hole. The inflatable salvage bag 1 is preferably in the deflated state during insertion. Preferably, a part of the stiffening element is inserted into the elongated sleeve 7, before the inflatable salvage bag 1 is inserted into the hole in a hull structure. Thereby the insertion of the inflatable salvage bag 1 against the pressure of fluid flowing through the hole is improved. Preferably, two friction bands 6 arranged in an X shape serve as a visual guide to align the lengthwise middle of the inflatable salvage bag 1 with the perimeter of the hole during insertion. Before or after insertion of the inflatable salvage bag 1, the valve 5 is connected to the first connection piece 21A of the flexible tube 18 and the valve 22 is or remains connected to the second connection piece 21B of the flexible tube 18.
Next, the inflatable salvage bag 1 is inflated, by letting gas flow from the pressurized gas source 19 into the inflatable salvage bag 1. The inflatable salvage bag 1 expands, preferably within a few seconds. During inflation, the outer surface of the inflatable salvage bag 1 expands, restrained by the perimeter of the hole in a hull structure. Therefore, the inflatable salvage bag 1 forms a secure fit with the perimeter of the hole in a hull structure. The parts of the inflatable salvage bag 1 protruding from either side of the hole preferably expand to a larger diameter than the part restrained by the perimeter of the hole. Thereby a secure placement of the inflatable salvage bag 1 is achieved. The securely placed and expanded inflatable salvage bag 1 reduces the fluid flow through the hole in a hull structure. Preferably the inflatable salvage bag 1 reduces at least 90% of the fluid flow through the hole, more preferably at least 95% of the fluid flow. Thereby the inflatable salvage bag 1 achieves an improved reducing of fluid flow through a hole in a hull structure of a marine vessel or a moveable storage tank. As the expansion is driven by pressurized gas, no operator force is required other than the force needed to hold the inflatable salvage bag 1 in place during expansion. Thereby a much-improved handling is achieved. Advantageously, the speed of deployment of the portable salvage system according to the invention is much improved over conventional systems. The application of wooden plugs may, for instance, take minutes, as opposed to the few seconds needed for expanding the inflatable salvage bag of the invention. This is an important advantage during emergency salvaging operations when time is a critical factor.
Gas can be released from the inflatable salvage bag 1 in the inflated state, by activating the first release lever 15 or the second release lever 23. Either of the release levers 15, 23 may be activated in order to prevent overfilling of the inflatable salvage bag, or to partially or fully deflate an inflatable salvage bag 1. Advantageously, deflating can thereby be performed by an operator positioned close to the inflatable salvage bag 1 inserted in the hole in a hull structure or by an operator carrying the pressurized gas source 19, possibly at a distance from the hole. Overfilling of the inflatable salvage bag 1 is further prevented by over pressure valve 24. Thereby, possible failure of the inflatable salvage bag 1 due to overfilling may securely be prevented. During or after expansion, the stiffening element may be removed from the elongated sleeve 7. Alternatively, a section of the stiffening element may be left in place in the elongated sleeve 7.
Once the inflatable salvage bag 1 is securely expanded in place, the flexible tube 18 can be disconnected from the expanded inflatable salvage bag 1. Should the hole have an elongated or irregular shape, it may be necessary to apply two or more inflatable salvage bags 1 to the hole, in order to reliably reduce the flow therethrough. Finally, in an emergency salvaging operation with little or no ambient light, the optional light source on the inflatable salvage bag 1 may have to be activated by an operator.
After use, the inflatable salvage bag 1 can be deflated, retrieved from the hole, optionally washed, dried, checked for damage and preferably reattached to the holding plate 17. Furthermore, the pressurized gas source 19 may be refilled. Refilling can be performed at any filling station comprising a source for compressed gas, where the gas preferably is air or a mixture including air. The optional light source may have to be replaced or refitted with batteries. The portable salvage system 16 can then be reassembled and preferably stored in the carrying bag, ready for renewed use.
The portable salvage system 16 may be used for reducing flow through a hole in a hull structure of a marine vessel or in a storage tank. Alternatively, or additionally, the portable salvage system 16 may be used to reduce flow through man-holes in an industrial structure or in a vessel. Thereby, ingress of seawater may, for instance, be limited to a lower deck of a ship only. Further alternatively, the portable salvage system 16 may be used to reduce or prevent flow through storm drain inlets or sewer inlets, such as found in streets or other public spaces. For instance, water in a sewer system may be prevented from exiting through a sewer inlet and flooding a street.
| Number | Date | Country | Kind |
|---|---|---|---|
| 20201247 | Nov 2020 | NO | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/NO2021/050199 | 10/1/2021 | WO |
