Abstract:
The present invention relates to device for preventing fouling of marine piles and the like. There is provided a marine pile antifouling device including a buoyant, substantially annular body for installation about a pile or the like, and having a working clearance about said pile or the like, wherein at least the outer surface of said body may be constructed of polymer foam or closed surface plastic. In one embodiment a marine pile antifouling device including a buoyant, resilient, unitary and substantially annular body, openable against said resilience for installation about a pile, and having a working clearance about said pile is provided. It has been surprisingly determined that a body of quite soft material representing no risk to the integrity of the pile surface is capable of maintaining the pile surface substantially free of marine fouling and growth.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to device for preventing fouling of marine piles and the like. 
         [0003]    This invention has particular application to inhibiting the growth of marine organisms on the surface of marine piles and the like, and for illustrative purposes the invention will be described hereinafter with reference to this application. However, it will be appreciated that this invention may find use in alternate applications, such as prevention of waterline fouling of floating objects such as buoys and moorings. 
         [0004]    2. Definitions 
         [0005]    In the specification and claims the term “comprising” shall be understood to have a broad meaning similar to the term “including” and will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps. This definition also applies to variations on the term “comprising” such as “comprise” and “comprises”. 
         [0006]    The reference to any prior art in this specification is not, and should not be taken as an acknowledgement or any form of suggestion that the referenced prior art forms part of the common general knowledge. 
         [0007]    Immersed marine structures including pylons, piles and pier supports are a substrate for a wide variety of fouling marine organisms. Mollusks and other shell forming organisms such as oysters, barnacles, mussels and the like may colonize immersed structures, including immersed concrete, coated metal surfaces, timber and PVC coated piles. Hard colonial deposits such as coralline algae and true corals, as well as soft fouling by algal species, seaweed, sludge and the like, may contribute to fouling of immersed surfaces. Fouling may damage vessels coming alongside, and in the case of marina piles, increase the rate of wear of the rollers. In the case of coated piling, fouling or its removal may damage the coating, leading to corrosion. 
         [0008]    The increased roughness of the surface of the support allows other attaching organisms to better avoid removal by waves, wind and tides, obscuring visibility and development of an unsightly build up on the support, particularly just above and just below the water level. 
         [0009]    Traditional methods of cleaning such supports include intermittently actively scraping the organisms from the support. Such methods use quite strong brushes or scrapers which can and often do damage the support itself. In many instances such cleaning requires a diver to enter the water and manually scrape the shells from the support surface. 
         [0010]    Other methods aim to deal with the problem by inhibiting growth of the organisms rather than removing the shells etc once formed. Such methods include using copper-containing antifouling paints on the support to deter attachment or “wrapping” the support in a material such as copper which will not allow interaction between the organisms and the underlying support. However, copper and its salts are toxic to most marine life and are subject to environmental recovery rules when redone. This is difficult or impossible in situ. 
         [0011]    Various apparatus exist which interact with the support itself to aim to deter growth of marine organisms. Many include strong brushes or scrapers which may damage the support, while others must be applied to the support during construction. Yet others are incredibly cumbersome and their installation and maintenance is quite labor intensive. 
         [0012]    These methods have many disadvantages; they are labor intensive, expensive and potentially quite harmful to the environment. Thus, it would be advantageous if an apparatus could be devised which would inhibit attachment of marine organisms and the like, while being easy to use, fit and maintain. 
       SUMMARY OF THE INVENTION 
       [0013]    According to a first aspect of the present invention there is provided a marine pile antifouling device including a buoyant, resilient, unitary and substantially annular body, openable against said resilience for installation about a pile or the like, and having a working clearance about said pile or the like. 
         [0014]    It has been surprisingly determined that a body of quite soft material representing no risk to the integrity of the pile surface is capable of maintaining the pile surface substantially free of marine fouling and growth. This effect even occurs in respect of hard fouling organisms. It is theorized that the hard fouling organisms are disrupted in colonizing the surface before the organism can lay down calcium salts as shell or the like. 
         [0015]    In one embodiment the device may be constructed at least partially of an appropriate polymer foam or closed-surface plastic. 
         [0016]    In one embodiment the invention provides a marine pile antifouling device including a buoyant, substantially annular body for installation about a pile or the like, and having a working clearance about said pile or the like, wherein at least the outer surface of said body may be constructed of polymer foam or closed surface plastic. In such an embodiment the body may be assembled from two or more individual segments. 
         [0017]    In a preferred embodiment the device may be constructed at least partially of low density polyethylene foam. 
         [0018]    In one embodiment the device may also include closure means to allow the device to be closed about the pile. In a preferred embodiment the closure means releasably closes the device. Suitable closure means may include, but are not limited to, interaction between opposing ends of the body of the device, presence of extensions positioned at ends of said body which associate to close said device, presence of one or more fasteners to aid in preparing and maintaining the device in a closed position, or a combination of any of the above. 
         [0019]    The closure means may include an outer casing which is applied to at least a part of the outer surface of said body. While the casing may be attached to the body of the device, in a preferred embodiment the casing may be independent of the body of the device. In a preferred embodiment the casing may be a C-shaped casing. 
         [0020]    Where one or more fasteners is/are present, it/they may or may not be integral with the body of the device. Appropriate fasteners may include but are not limited to strapping, rope, belt and buckle, zip tie, clips, butterfly clips, loops, hooks, mating male (hook) and female (loop) strips, best known as VELCRO-type strips (VELCRO being a trademark of Velcro Industries B.V. Ltd. Liab. Co.), or other hook-pile fastening and studs, or any combination thereof. 
         [0021]    The body may comprise a monolithic foamed structure of open or closed cell polymer material. The closed cell material may include a closed surface. The open celled material may be formed in situ in a hollow sleeve or the like, which may also be of polymer or may be of any other suitable material. Preferably the material is relatively soft in order to avoid damage to the piling. 
         [0022]    The body member may comprise a hollow body, again preferably of plastics material or the like. The plastics material may be advantageously selected from thermoplastic materials that are readily injection blow or rotary molded, such as polyolefins. For example the body member may be formed of polyethylene or polypropylene. The body may be a combination of an inner body of plastics materials and an outer surface of polymer material. 
         [0023]    In one embodiment the device may be of a material that deforms in shape upon contact with the marine pile or the like. 
         [0024]    In another embodiment the invention provides a method of inhibiting attachment of matter to a marine pile or the like, wherein the method includes placing a device as discussed above around said pile or the like, such that said device floats on the waters surface and capable of movement about said pile in response to ocean forces. In a preferred embodiment the device is placed around said pile or the like after the pile or the like which was previously in position. 
         [0025]    In one embodiment the invention advantageously provides a device which cleans at and/or above the water line or the so-called splash-zone. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0026]    The present invention will now be described by way of the following description having reference to the figures, wherein: 
           [0027]      FIG. 1  is one embodiment of a marine pile anti-fouling device in accordance with the current invention; 
           [0028]      FIGS. 2 and 3  depict a cross section of one embodiment of the device in place around a pile; 
           [0029]      FIGS. 4 to 8  display various embodiments of the optional closure means for closing a marine pile anti-fouling device in accordance with the invention around a pile; 
           [0030]      FIGS. 9 to 13  depict one embodiment of an optional closure means, including a C-shaped casing in accordance with the current invention; 
           [0031]      FIGS. 14 and 15  depict an embodiment including a C-shaped casing in use about a pontoon strut; and 
           [0032]      FIGS. 16 and 17  depict two other embodiments of a marine pile anti-fouling device in accordance with the current invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0033]    In  FIG. 1  a marine pile anti-fouling device ( 10 ) in accordance with the invention is depicted. The device is designed to prevent marine organisms attaching to a marine pile or similar marine structure including pylons, pontoons, piers and jetties. In this way it not only deters organisms like seaweed becoming wrapped around the pile and algal like organisms from attaching and growing on the pile, it also stops opportunistic shell forming organisms from attaching to the pile and forming shells which can be quite dangerous as well as unsightly. The device may inhibit the attachment of organisms such as oysters, mollusks, barnacles and other shell forming organisms, algal and mould species and seaweed and other plant material. 
         [0034]    Advantageously the device may be applied to an existing structure, including structures where uninterrupted access is not possible from the top of the structure (for example pontoon struts where a device may not be slid down from the top of the strut due to the horizontal landing of the pontoon itself restricting access). 
         [0035]    The depicted embodiment is circular, however it should be noted that any substantially annular shape may be used. For example the device may be substantially oval, or it may be pentagonal, hexagonal or any other suitable multi- sided shape. The shape may vary depending upon the shape of the support it is designed to fit, however it should be noted that the shape of the support and the device do not need to be the same. 
         [0036]    The device is formed of a buoyant material such that the apparatus will float on the surface of the water. 
         [0037]    The device is designed to move about the pile with the marine forces including waves, tides and currents. 
         [0038]    As depicted in  FIGS. 2 and 3 , to allow movement of the device about the pile, the body ( 20 ) of the device is sized such that there is a working clearance ( 22 ) between the pile ( 24 ) and the device itself when in place around the pile ( 24 ). A working clearance exists when there is sufficient clearance between the device ( 20 ) and the pile ( 24 ) such that the device ( 20 ) is able to move about the pile to an adequate degree to allow the device to intermittently collide with the pile ( 24 ) at random locations as the device is actuated by the marine forces. The action of the device colliding with the pile inhibits the attachment of organisms to the pile. The working clearance ( 22 ) will vary depending upon the shape and size of the pile. 
         [0039]    In one embodiment the body of the device ( 20 ) may be composed of any appropriate buoyant and resilient material. Preferably the material also has a low inertia to allow the device to move with the ocean forces. Suitable materials in this regard include, but are not limited to, low density polyethylenes and closed surface plastics. 
         [0040]    The body may be hollow or may be solid. 
         [0041]    The body may be formed of a material that deforms upon contact with the pile or the like. For example the body may be composed of a soft and deformable plastics material, rubber or silicon. In such embodiments the body is preferably hollow and may be weighted to avoid displacement from the pile and to aid in facilitating anti-fouling, for example the body may be at least partially filled with liquid. 
         [0042]    In one embodiment at least the outer surface of the body may be composed of material that is relatively soft. For instance the material may resiliently deform when it comes into contact with the pile or a marine organism. In one embodiment the entire body may be formed from such a material. Alternatively only the outer surface of the body may be composed of this material while the inside portion of the body may be composed of a material which is at least resilient and buoyant. The advantage of using a material that is relatively soft is that damage to the pile due to contact with the device would be minimal. Suitable materials in this regard include, but are not limited to, low density polyethylenes and closed surface plastics. 
         [0043]    The body may be a foamed structure of open or closed cell polymer material. The closed cell material may include a closed surface. The open celled material may be formed in situ in a hollow sleeve or the like, which may also be of polymer or may be of any other suitable material. Preferably the material is relatively soft in order to avoid damage to the piling. The body member may comprise a hollow body, again preferably of plastics material or the like. The plastics material may be advantageously selected from thermoplastic materials that are readily injection blow or rotary molded, such as polyolefins. For example the body member may be formed of polyethylene or polypropylene. The body may be a combination of an inner body of plastics materials and an outer surface of polymer material. 
         [0044]    In one embodiment of the invention the body of the device may be unitary in nature. The resilience of the body allows the body to be manipulated such that its installation around a pile (and removal therefrom if necessary) is allowed. 
         [0045]    In another embodiment the body of the device may be an assembled body composed of two or more individual segments. The segments may be assembled by any suitable means to form a substantially annular body. For example the segments may be associated by a linking material connecting the segments or a casing may be applied to a part of the outer surface of the body to effectively assemble the segments in an annular arrangement. 
         [0046]    The device need not fully surround the pile, however it must surround the support such that it is not easily removed without interference from a user. For example the device should sufficiently surround the support such that wave force will not force the apparatus to be removed from the support. 
         [0047]      FIGS. 2 and 3  depict one embodiment of the device ( 20 ) in place about a marine pile ( 30 ). In  FIG. 2  the device ( 20 ) is in a position such that it is not in contact with the marine pile ( 24 ) due to the equal spread of the working clearance ( 22 ). In  FIG. 3 , marine forces such as waves, tide etc have pushed the device ( 20 ) in a particular direction (arrow A) such that a portion of the device comes into contact with the marine pile ( 24 ) at position B. As marine forces are constant and direction variable the device ( 20 ) is moved randomly and comes into contact with the marine pile ( 24 ) at random locations. The contact between the device ( 20 ) and the pile ( 24 ) deters attachment of marine organisms (including shell forming creatures, algae, seaweed etc) and thus diminishes fouling of the pile itself. 
         [0048]    The working clearance ( 22 ) required will be proportional to the size of the pile. For example piles with a large circumference will require a greater working clearance than those with smaller circumferences. 
         [0049]    In the embodiment depicted in  FIG. 1 , the device consists of the body itself only. The body in  FIG. 1  is designed such that the body is discontinuous due to the presence of a “cut” ( 12 ). A user may simply pull opposite parts of the body ( 10 ) apart, widening the “cut” ( 12 ) to allow for placement around a pile. Once in place, the user will release the body and due to its resilience it will reform the original shape in its place around the pile. 
         [0050]    In most marine environments, the body alone (i.e. without additional closure means) would withstand marine forces and not be forced from the pile without user interference. However, in some situations, for example where very strong tidal, current or wave forces exist, the need may exist for a closure means. 
         [0051]    The closure means may include any means capable of closing the body. Preferably the closure means allows releasable closure of the body, although permanent closure may also be suitable. The body itself may provide the closure means, for example, the opposite ends of the body may associate as a male/female relationship or the ends may include opposing interconnecting appendages. Alternatively the closure means may be separate to the body itself, for example one end of the body may include a hook while the other end may include an appropriate loop for receiving the hook, or in another example the ends may be bound together by suitable means (e.g., zip ties, rope, buckles, etc.) once in place. The body itself may include extensions at each end which interact to form the closure means, for example one such extension may have a loop which extends over the second extension. Other closure means may include a closure strip fed through the body (either introduced during manufacture or fed through a hollow formed body) and extending out at either end may be connected to close the body, for example by tying, clipping, buckling or the like. 
         [0052]    Possible closure means are depicted in  FIGS. 4 to 8 . These are not intended to represent an exclusive list of appropriate closure means but rather examples of closure means that may be useful if necessary. Any other appropriate closure means may be used. 
         [0053]    In  FIGS. 4 and 5  the ends of the body (( 40  &amp;  42 ) and ( 44  &amp;  46 ) include extensions (( 48  &amp;  50 ) and ( 52  &amp;  54 )). The extensions may be vertical as in  FIG. 4  ( 48  &amp;  50 ) or horizontal as in  FIG. 5  ( 52  &amp;  54 ). Once the device is in place around a pile the extensions may be brought into close proximity to allow the device to be closed around the pile to lessen the likelihood of unintentional removal. The extensions may be held together by any appropriate fastening means including a zip tie ( 58 ), buckle, rope etc. The fastening means may be separate from the device itself or it may be integral with the device. For example the fastening means may be a hook integrally associated with a first extension, which when the extensions are brought into close proximity the hook may be placed over the second extension to secure them together. Alternatively, the fastening means may be for example a belt and buckle that are applied to the device once in place around a pile and the extensions brought into close proximity. Examples of suitable fastening means which may or may not be integral to the device include strapping, rope, belt and buckle, zip tie, clips, butterfly clips, loops, hooks, mating male (hook) and female (loop) strips, or other hook-pile fastening, studs, any other suitable fastening means, or any combination thereof. 
         [0054]    In another embodiment the body itself may be arranged to facilitate closure of the device about a pile. For example, in  FIG. 6  the opposing ends ( 60  &amp;  62 ) of the body of the device ( 10 ) are arranged to interlock to allow closure. One end of the body ( 60 ) is designed to accept the second end ( 62 ). A user will easily be able to interlock the opposing ends, however unintentional removal due, for example, to strong waves or very strong currents, will be reduced. 
         [0055]    In another embodiment fastening means may be used to hold the two opposing ends of the body themselves in close proximity. For example a pin or clip may hold the two ends in close proximity.  FIGS. 7 and 8  depict an example of this embodiment. The opposing ends ( 70  &amp;  72 ) of the body are designed to overlap when brought into contact. For example, in the depicted embodiment the opposing ends have been finished with an opposing gradient such that the ends overlap when brought together rather than simply abutting against each other. One or more pins, clips or the like may be placed through the two ends to join them together to affect closure of the device. In  FIGS. 7 and 8  two pins ( 74  &amp;  76 ) are used to close the device. Although two pins are depicted, it is possible that only one pin may be used, or alternatively that more than two pins may be used. The pin or clip may pass completely through one end of the device and only partially through the second end as is depicted in  FIGS. 7 and 8 . Alternatively the pin or clip may pass completely through both ends of the device. Examples of suitable fastening means which may or may not be integral to the device include strapping, rope, belt and buckle, zip tie, dips, butterfly clips, loops, hooks, mating male (hook) and female (loop) strips, or other hook-pile fastening, studs, any other suitable fastening means, or any combination thereof. 
         [0056]    In one embodiment the closure means may be a casing that is applied to at least a part of the outer surface of the body. A casing offers a number of advantages including protection of the device from the elements and from animals including birds, it may be used as a template for the application of signage or it may be coated in glow-in-the-dark paint to act as an identification marker. The casing may be used with embodiments of the invention where the body is unitary or is composed of individual segments. The casing may be integral with the body of the device or it may be separate. For example, where the casing is integral with the body it may be attached to one end of the body and may be pulled around the outer side of the outer surface of the body once it is in place around the pile, or it may aid in placement of the body about the pile. 
         [0057]    While the casing may be applied to embodiments wherein the body is composed of a single unitary body, in embodiments where the body is composed of individual segments the casing may be used to assist in assembly and retention of the segments in a substantially annular arrangement about the pile or the like. To allow the device to function as a marine anti-fouling device, it is important that the casing allows the body to contact the pile (or the like). For example the body may protrude from the inside of the casing or the casing may be shaped to allow part of the inner wall or the body to contact the pile (or the like), e.g. the casing may be C-shaped with an open section on the inner wall of the casing. 
         [0058]    In an embodiment depicted in  FIG. 9 , the casing may be a C-shaped casing ( 78 ) which is applied to the outer wall of the outer surface of at least a segment of the body ( 79 ) of the device such that at least the wall/s of the body that would ordinarily come into contact with the pile or the like during use would still be free to access the pile. 
         [0059]    As exemplified in the embodiment depicted in  FIG. 9 , the body may be composed of two separate segments ( 80  and  82 ), and the casing also may be composed of two separate parts ( 84  and  86 ). Each part ( 84  and  86 ) of the casing being applied to the outer wall of the outer surface of an individual body segment ( 80  and  82 ). 
         [0060]    The inner surface of the body segments ( 80  and  82 ) are able to contact the pile (or the like) as the casing is C-shaped and the body is able to access the pile from inside the casing. This is depicted in  FIGS. 10 and 11 , wherein part of the body segment ( 80 ) is able to access the pile from the open side of the C-shaped casing part ( 84 ). 
         [0061]    The casing parts ( 84  and  86 ) may include one or more fastening means ( 88  and  90 ) to allow closure of the casing and thus assembly of the body segments about the pile or the like. A close up view of an appropriate fastening means is depicted in  FIG. 12 . The fastening means ( 100 ) in this embodiment is comprised of two interlocking pieces, wherein one piece ( 102 ) includes a hole ( 104 ) adapted to receive a projection ( 108 ). In the depicted embodiment the hole ( 104 ) is slightly larger than the projection diameter although this is not necessary. One of the pieces of the fastening means may be recessed such that when the pieces interact the side opposite the interlocking pieces sits flush. This is also demonstrated in the embodiment depicted in  FIG. 13 . As depicted in  FIG. 12 , the fastening means may also include a securing means ( 110 ) for securing the casing parts together. For example, the projection ( 108 ) may include a hole through which a tie may be passed and secured to limit separation of the casing parts. While this is not essential it may be advantageous where conditions are particularly unstable, for example during storms, high winds, extreme tides or where there is high local boat activity. 
         [0062]    A casing may aid in positioning and retention of the device about a pile or the like. In particular such casing would be useful for embodiments wherein the body of the device is composed of more than one segment. In such an embodiment the body segments of the device may be placed within a corresponding casing part and the casing parts then assembled about a pile or the like. Such an embodiment is depicted in use in  FIGS. 14 and 15 . In this embodiment the device ( 120 ) has been placed about a pontoon strut ( 122 ). As the tide and/or ocean forces cause the water level to rise, the device ( 120 ) also rises up the strut ( 122 ). Similarly, as the tide and/or ocean forces cause the water level to fall, the device ( 120 ) lowers with down the strut ( 122 ). As the body of the device contacts the pontoon strut attachment of marine organisms (including shell forming creatures, algae, seaweed etc.) is deterred and thus fouling of the strut itself is diminished. Similarly to embodiments without casings discussed above, a working clearance between the body and the strut allows such movement. 
         [0063]    Such a casing may be made of any suitable plastics material. In preferred embodiments the casing may be constructed from medium density plastics material, polyethylene, or any other marine suitable plastic. 
         [0064]    The device may be formed by any suitable method. For example where a suitable material is used the device may be formed by foam extrusion. 
         [0065]    The device may be formed as a single unit or alternatively may be formed as separate pieces and assembled into a unitary device. For example the body of the device may include more than one partial body units which can be assembled to form a unitary body in use. The device may also be formed such that the inside of the body may be formed separately from a relatively hard buoyant, resilient material, which is subsequently coated in a polyethylene outer formed by foam extrusion. 
         [0066]    Due to the soft nature of at least the outer surface of the body, the device may also act as a buffer between the pile and any floating body, for example a boat or floating pontoon or the like. The annular body itself may be sufficient to provide some protection to both the pile and the floating body. Alternatively the body may include one or more impact buffers on the outward facing surface/s of the body. Impact buffers may be composed of the same material as the remainder of the body of the device, alternatively any other suitable material may be used. In one embodiment it/they may be inflatable. 
         [0067]    The embodiment depicted in  FIG. 16  is one embodiment which may act dually as an anti-fouling device and an impact buffer. I n this embodiment the body ( 80 ) of the device is conical, in this case the outer diameter of the bottom of the body is wider than the top. The inner diameter of this embodiment may be uniform throughout the length of the body. 
         [0068]    In addition to functioning as an anti-fouling device, the device may also carry out other advantageous roles. For example the device may be shaped to allow signage to be applied to the outer surface, for example the outward facing portion of the outer surface of the body at least may include a flat surface to allow the application of signage; for example advertising, location/direction markers, warnings.  FIG. 17  displays an embodiment which may be suitable for the application of signage. The body of the device may be produced from or have affixed thereto material that glows in the dark or is reflective. This would allow the pile to be located at night by people on land or water, providing additional safety measures. 
         [0069]    Although the foregoing description of the present invention has been shown and described with reference to particular embodiments and applications thereof, it has been presented for purposes of illustration and description and is not intended to be exhaustive or to limit the invention to the particular embodiments and applications disclosed. It will be apparent to those having ordinary skill in the art that a number of changes, modifications, variations, or alterations to the invention as described herein may be made, none of which depart from the spirit or scope of the present invention. The particular embodiments and applications were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such changes, modifications, variations, and alterations should therefore be seen as being within the scope of the present invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled.