Patent Publication Number: US-9409305-B2

Title: Cutting apparatus and method

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to cutters and, more particularly, to a cutter comprising interlocking, articulating cutting bushings adapted to actuate in a back and forth saw-like motion to cut a desired structure. 
     BACKGROUND OF THE INVENTION 
     In conventional marine salvage operations, given the size of some structures, it is sometimes necessary to remove the structure in a piecemeal fashion. Thus, various cutting methods have been employed. One such method involves the use of a wire having a plurality of loose bushings slidable along the wire. The wire is actuated in a back and forth saw-like motion to cut the desired structure. Another method involves the use of a chain which is actuated back and forth to cut the structure. 
     These methods have a variety of disadvantages. In the first method, the bushings are not attached to one another. Therefore, in instances when the wire breaks during operations, bushings simply slide off the wire into the surrounding water. As a result, costly retrieval operations must be conducted, or bushings have to be replaced. In methods employing the chain, cutting operations are extremely violent since the chain really does not cut the structure, but rather “tears” it, resulting in a very jagged “cut” and a dangerous working environment. In addition, since adjacent links in the chain are oriented along planes which are perpendicular to one another, every other link bears the majority of the cutting stresses, resulting in a less efficient cutting operation with greater safety risk to personnel and equipment. 
     Accordingly, there is a need in the art for a cutter having interlocking, articulating bushings, therefore providing a means to achieve a safer, efficient, and cost-effective marine salvage operation. 
     SUMMARY OF THE INVENTION 
     The present invention provides apparatuses and methods for a cutting apparatus comprising interlocking, articulating cutting bushings. A plurality of bushings is coupled to one another via a series of bolts. The bolts have a cylindrical end and a convex end. The convex ends are seated inside a concave socket coupled to the interior bore of the bushings. The cylindrical ends are threaded to a convex nut which seats inside another concave socket coupled to the bore of an adjacent bushing. The convex ends of the bolts are configured to articulate inside the seat of the concave sockets, thereby allowing the bushings to articulate in relation to one another. A hardened or flexible washer may be placed between the bushings to provide a desired amount of flexibility and/or rigidity. The outer surface of the bushing comprises a cutting structure, such as a milled or clad cutting structure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a sectional view of a cutter according to an exemplary embodiment of the present invention; 
         FIG. 1B  is an alternate view of the cutter illustrated in  FIG. 1A ; 
         FIG. 2  illustrates a clad bushing of a cutter according to an exemplary embodiment of the present invention; 
         FIG. 3A  is an expanded view of a cutter according to an exemplary embodiment of the present invention; 
         FIG. 3B  is an alternate view of the cutter illustrated in  FIG. 3A ; 
         FIG. 4A  illustrates the vertical operation of the cutter according to an exemplary embodiment of the present invention; and  4 B the horizontal operation of the cutter according to an exemplary embodiment of the present invention. 
         FIG. 5A  illustrates an isometric view of a cutter according to an embodiment of the current invention;  FIG. 5B  shows a cutter with a flexible washer;  FIG. 5C  depicts a cutter with a rigid washer;  FIG. 5D  illustrates a cutter without any washers.  FIG. 5E  depicts a cutter with a mixture of rigid and flexible washers; and  FIG. 5F  illustrates a cutter with a mixture of flexible, rigid and no washers. 
     
    
    
     DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 
     Illustrative embodiments and methodologies of the present invention are described below as they might be employed in a cutter or method employing the cutter. In the interest of clarity, not all features of an actual implementation are described in this specification. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the developers&#39; specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure. Further aspects and advantages of the various embodiments and methodologies of the invention will become apparent from consideration of the following description and drawings. 
       FIG. 1A  illustrates a cutter according to an exemplary embodiment of the present invention. Cutter  10  includes a plurality of bushings  12  having milled cutting surfaces along the outer diameter. In this exemplary embodiment, bushings  12  are approximately 60 mm long by 80 mm in diameter, however, those ordinarily skilled in the art having the benefit of this disclosure realize the dimensions of bushings  12  may be varied. Threads  14  are present along inner bore  16  of bushings  12  at each end of bushings  12 . An interior concave socket  18  having a threaded outer diameter is threadingly coupled to threads  14  of bushings  12 . 
     A convex shouldered bolt  20  is positioned inside interior concave socket  18 . At one end of convex shouldered bolt  20  is a cylindrical end  22 , while the other end comprises the convex end  24 . Convex end  24  seats inside concave interior socket  18  such that convex shouldered bolt  20  is allowed to articulate a certain degree, as will be discussed later. End  22  of convex shouldered bolt  20  comprises threads  30  along its outer diameter. A convex nut  32  is threadingly coupled to convex shoulder bolt  20  via threads  30 . Convex nut  32  seats inside concave interior socket  18  of the adjacent bushing  12 . Accordingly, any number of bushings  12  may be coupled to each other in such manner. 
     Further referring to the exemplary embodiment of  FIG. 1A , once positioned inside bore  16  of bushing  12 , the outer end of concave interior socket  18  rests substantially flush with the end of bushing  12 . A washer  26  is positioned around convex shouldered bolt  20  between adjacent bushings  12  in order to provide rigidity to cutter  10 . Washer  26  may be made of metallic or non-metallic material, such as, for example, rubber, neoprene, or polyethylene. In this exemplary embodiment, washer  26  is approximately 8 mm thick by 40 mm in diameter. Depending on the width of washer  26 , the outer ends of concave interior sockets  18  of adjacent bushings  12  either rest against or are adjacent to the ends of washer  26  when cutter  10  is in a substantially straight position. 
     In embodiments utilizing a hardened washer  26 , cutter  10  will be more rigid and, thus, will flex less, or not at all, during cutting. However, in embodiments utilizing a flexible washer  26 , cutter  10  will be flexible and have more ability to articulate. Those ordinarily skilled in the art having the benefit of this disclosure realize the material used in washer  26  and/or the size of washer  26  may be varied to accomplish a variety of angles of curvature or rigidity within cutter  10 . Moreover, in order to provide maximum flexibility, an alternate exemplary embodiment of the present invention omits washer  26  altogether. In addition, cutter  10  may comprise a combination of hardened, flexible, and omitted washers in order to achieve the desired cutter characteristics. 
     The exemplary cutter  10  of  FIG. 1A  comprises a milled outer surface composed of teeth  28  which are circumferentially placed around the outer surface of bushing  12 . The respective teeth  28  of adjacent bushings  12  are oriented in opposing directions of each other. As illustrated in  FIG. 1 , the cutting surfaces of teeth  28  along the left bushing  12  are all oriented toward the left, while teeth  28  along adjacent right bushing  12  are oriented in the right direction. As such, cutter  10  cuts in both directions as it is actuated.  FIG. 1B  is an alternative view of  FIG. 1A . In the alternative exemplary embodiment of  FIG. 2 , bushing  12  may comprise a variety of clad cutting surfaces, such as tungsten carbide, polycrystalline diamond compact, diamond, or other cutting surfaces, or some combination of cutting surfaces. In yet another exemplary alternate embodiment, teeth  28  of a single bushing may be oriented in opposing directions as well. 
     Assembly of cutter  10  will now be described in relation to an exemplary embodiment of the present invention. When assembling cutter  10 , convex interior socket  18  is threadingly coupled to threads  14  of a first bushing  12 . Concave interior socket  18  comprises pin holes  34  in its outer surface. A pin wrench, as known in the art, is utilized to screw concave interior socket  18  into threads  14 . Thereafter, convex shouldered bolt  20  is seated inside concave interior socket  18 . A washer  26 , if desired, followed by a second concave interior socket  18  are slid over end  22  of shouldered bolt  20 . Convex nut  32  is then threaded onto end  22  via thread  30  and then inserted into the second bushing. The second concave interior socket  18  is then coupled to the second bushing  12  into threads  14 . 
     Now two bushings  12  have been coupled to each other, and each bushing has an open end ready to receive further sockets  18  and bolts  20 . Thus, a second convex shouldered bolt  20  is seated in a concave interior socket  18  and, then, threaded (via pin holes  34  and pin wrench) into one of the open ends of the first or second bushings  12 . Any number of bushings may be added to cutter  10  in like manner. Disassembly of cutter  10  would be achieved in a reverse manner, as would be apparent to one ordinarily skilled in the art having the benefit of this disclosure. Although not shown, end  24  of convex shouldered bolt  20 , as well as the inner end of convex nut  32 , also comprise pin holes  34  which are utilized with the pin wrench in assembly/disassembly. 
       FIGS. 3A &amp; 3B  illustrate expanded views of cutter  10  according to an exemplary embodiment of the present invention. Here, cutter  10  comprises the same components previously described in relation to  FIGS. 1A &amp; 1B . Moreover, any number of bushings  12  may comprise cutter  10 , as desired. At each end of cutter  10 , the outermost bushings  12  comprise convex shouldered bolt  20  having cylindrical end  22  and convex end  24 . In this exemplary embodiment, however, unlike the other convex shouldered bolts  20 , cylindrical end  22  of the outermost convex shouldered bolt  20  is threadingly coupled to a threaded pad eye receiver  36  and a shackle or clevis  38 . An exemplary shackle is disclosed in U.S. Pat. No. 7,654,594, entitled “SHACKLE,” issued Feb. 2, 2010, owned by the Assignee of the present invention, Bisso Marine Co., Inc. of Houston, Tex., which is hereby incorporated by reference in its entirety. An actuator  40  is coupled to shackle  38 . Actuator  40  may be a hydraulic unit operated by a programmable power unit, such as a constant tension winch or hydraulic ram, or any other means known in the art. 
     Referring to  FIGS. 3A, 3B, 4A, and 4B , operation of the cutter will now be described in relation to a salvage operation to remove submersed shipwreck  42 .  FIG. 4A  illustrates vertical operation of the cutter, while  FIG. 4B  illustrates horizontal operation of the cutter. A liftboat having an actuator  40  is coupled to cutter  10  via shackle  38  and tether  44 , or any other means known in the art. Cutter  10  has been deployed underneath shipwreck  42 , as illustrated in  FIG. 4 , and will accomplish the cutting in the upward direction. In the alternative, cutter  10  may be placed atop a desired structure, such as when the structure is floating atop the water surface or located on land, and cutting is accomplished downwardly. Those ordinarily skilled in the art having the benefit of this disclosure realized a variety of objects may be cut in a variety of directions utilizing the present invention. Accordingly, the cutter of the present invention is omnidirectional and may also be employed below mudline or topside. 
     In yet another alternate embodiment, cutter  10  may be placed around a desired structure  54 , and cutting will be achieved in a horizontal direction, as illustrated in  FIG. 4B . Referring to  FIG. 4B , lines  44  are attached to a barge  50  on one end and a liftboat, as previously described, on the other end. An anchor or clump weight  48  is positioned underwater and fitted with a sheave to make the system cut in a horizontal direction, as illustrated. 
     Further referring to  FIGS. 3A, 3B, 4A, and 4B , actuator  40  actuates cutter  10  in a back and forth saw-like motion to effect cutting of shipwreck  42 . During cutting, bushings  12  articulate in relation to one another, thus allowing cutter  10  to bend around the body of shipwreck  42 . As cutter  10  is actuated, it begins to cut into, and eventually through, shipwreck  42 . Those ordinarily skilled in the art having the benefit of this disclosure realize the actuation speed and/or dimensions or cutting surface of bushings  12  may be varied to effect varying cutting efficiencies. 
     As shown in the exemplary embodiment of  FIG. 3A , washers  26  are comprised of a flexible material which compresses as bushings  12  bend toward one another, thereby allowing bushings  12  to articulate up to an angle Φ in relation to each other. In this exemplary embodiment, Φ=12°, therefore illustrating a total cutter angle of 60°. However, those ordinarily skilled in the art having the benefit of this disclosure realize Φ may be larger or smaller dependent upon whether washer  26  is utilized and, if so, what material comprises washer  26 . In addition, the dimensions of bushings  12 , convex shouldered bolt  10 , and concave interior socket  18  may be varied to effect varying ranges of articulation, as would also be understood by one of ordinary skill in the art having the benefit of this disclosure. 
     Accordingly, an exemplary embodiment of the present invention provides a cutting apparatus comprising a plurality of bushings, each bushing having a bore therethrough; a concave interior socket coupled to both ends of the bores of each of the plurality of bushings; and a bolt joining adjacent bushings, the bolt having a concave shouldered end and a cylindrical end, the concave shouldered end being seated inside the concave interior socket while the cylindrical end of the bolt is coupled to a convex nut, the convex nut being seated inside the concave interior socket of the adjacent bushing, wherein the plurality of bushing are configured to articulate in relation to one another. In another embodiment, the cutting apparatus further comprising a washer placed between the plurality of bushings, the washer located around the bolt joining adjacent bushings. In yet another exemplary embodiment, at least one of the washers is rigid and at least one of the washers is flexible. In another exemplary embodiment, the cutting apparatus comprises a washer placed between less than all of the plurality of bushings. 
     An exemplary cutter may further comprise pin holes located on an outer surface of the concave interior socket. In the alternative, teeth are located on an outer surface of the bushings. In yet another embodiment, the teeth of adjacent bushings are oriented in opposing directions. The outer surface of the cutting apparatus may be comprised of tungsten carbide, diamond, or polycrystalline diamond compact cutting structure. In yet another exemplary embodiment, the cutting apparatus further comprises an outermost bushing on each end of the cutting apparatus, each outermost bushing comprising a convex shouldered bolt extending outwardly from the cutting apparatus, a cylindrical end of the convex shouldered bolt being coupled to a mechanism which actuates the cutting apparatus in a back and forth saw-like motion. 
     Another exemplary embodiment of the present invention provides a cutting apparatus comprising a plurality of bushings, each bushing having a bore therethrough; and a bolt joining adjacent bushings, the bolt extending into a portion of the bore of the adjacent bushings, wherein the plurality of bushing are configured to articulate in relation to one another. In another exemplary embodiment, the cutting apparatus further comprises a washer placed between the plurality of bushings or a washer placed between less than all of the plurality of bushings. In yet another embodiment, an outer surface of the plurality of bushings comprises a milled or clad structure. 
     An exemplary methodology of the present invention provides a method for cutting a structure, the method comprising the steps of bringing a cutting apparatus into contact with the structure, the cutting apparatus comprising a plurality of bushings, each bushing having a bore therethrough, and a bolt joining adjacent bushings, the bolt extending into a portion of the bore of the adjacent bushings; actuating the cutting apparatus along the structure; and cutting the structure using the cutting apparatus. In another exemplary methodology, the step of actuating the cutting apparatus comprises the step of articulating the plurality of bushings in relation to one another. In yet another methodology, the step of bringing the cutting apparatus into contact with the structure further comprises the step of placing a washer between the plurality of bushings. In yet another exemplary methodology, at least one of the washers is flexible and at least one of the washers is rigid. 
     In another exemplary methodology, the step of bringing the cutting apparatus into contact with the structure further comprises the step of placing a washer between less than all of the plurality of bushings. In another methodology, the step of bringing the apparatus into contact with the structure comprises the step of providing teeth on an outer surface of the plurality of bushings, the teeth on adjacent bushings being oriented in opposing directions, and the step of actuating the cutter further comprises the step of actuating the cutting apparatus in a back and forth saw-like motion, the cutting apparatus cutting the structure in both the back and forth motion. In yet another exemplary methodology, the step of bringing the cutting apparatus into contact with the structure further comprises the step of providing a clad outer surface on the plurality of bushings. 
     Accordingly, various embodiments of the present invention provide a cutter having interlocking, articulating bushings. In instances where the cutter breaks during operation, the bushings will not be lost in the sea or require costly retrieval operations since they are interlocked. Moreover, the cutter can be quickly reassembled using the pin holes of the present invention. Furthermore, unlike the conventional chain cutters, the present invention allows for precision cutting of a structure. 
     Although various embodiments have been shown and described, the invention is not limited to such embodiments and will be understood to include all modifications and variations as would be apparent to one skilled in the art. For example, although described only in relation to marine salvage operations, the cutter of the present invention may be used to cut a variety of other structures and objects. Therefore, it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the invention as defined by the appended claims.