Abstract:
A system for temporarily joining two pipe ends securely in a reversible manner, where the joined pipe will carry fluids or mixed fluids and solids under high pressure and volume. Two clamshell clamps each grip a pipe near its end where two pipes are to be joined and. The clamshell clamps have two mating bodies of semicircular cross-section, pivoting around a hinged edge, so that interlaced flanges on the bodies&#39; other edges meet and between which mated flanges a conical pin is inserted to bias the mating clamp bodies together gripping the pipe inside the tubular enclosure formed by the mating clamp elements. The conical pins are connected so that if the pipes&#39; ends are urged apart, the connected pins are urged between the clamps&#39; flanges forcing the clamps&#39; gripping faces together on the pipes. The clamps may have included gripping elements adjacent on its inner face.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims priority under 35 U.S.C. §119(e) to U.S. provisional patent application No. 61/187,545 filed Jun. 16, 2010. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to clamps for rigid pipes and more particularly to a system and method for tethering the ends of rigid pipes together. 
       BACKGROUND OF THE INVENTION 
       [0003]    Temporarily joining two rigid pieces of pipe is necessary in a number of industries. These joins can be made by using hammer unions, other types of joins, etc. However, because these joins are only meant to be temporary, they are often not as strong as joins made to permanently connect the ends of two pipes, such as by simply welding the pipes together or coupling them in a more permanent manner. In many cases, especially when the joined pipes are going to be used to convey a highly pressurized fluid, it is often desirable to connect or tether the ends of the pipes together in addition to using the temporary join. In this manner, if the highly pressurized fluid passing through the pipes causes the temporary join to fail (i.e. a blowout), the tethering of the ends of the pipes can keep the ends of the pipes from moving too far. These pipes often also convey gases and solids in addition to or instead of fluids and can be subjected to abrasion and blowouts can release gas into surroundings. 
         [0004]    Previously, a number of measures have been taken to attempt to tether the ends of the two pipes together in the event that a temporary coupling fails and the pressurized fluid inside causes the two pipes to blow apart. However, many of these measures have not been all that successful and/or easy to use. 
       SUMMARY OF THE INVENTION 
       [0005]    It is to be understood that other aspects of the present invention will become readily apparent to those skilled in the art from the following detailed description, wherein various embodiments of the invention are shown and described by way for illustration. As will be realized, the invention is capable for other and different embodiments and is several its several details are capable of modification in various other respects, all without departing from the spirit and scope of the present invention. Accordingly the drawings and detailed description are to be regarded as illustrative in nature and not as restrictive. 
         [0006]    The invention is of a pipeline joining clamp system for holding two rigid pipes&#39; ends together in a reversible or temporary manner, comprising:
       a. Two clamshell clamps, each comprising:
           i. A first half comprising
               1. a half-pipe of semicircular cross-section the inner surface of which is sized to match and mate with the outer surface of a pipe to be joined near the joint   2. a loop attached to a straight edge of the half-pipe   3. a finger attached to the opposite edge of the half-pipe   
               ii. a second half comprising
               1. a second half-pipe of similar diameter to the first   2. a loop attached to a straight edge of the second half-pipe   3. a finger attached to the opposite edge of the second half-pipe   
               iii. a pin which inserted into the loops of the two half-pipes forms a hinge, constraining the half-pipes to rotate about the hinge to form a tube when closed   iv. the tube when closed having the fingers of the first and second half-pipes interleaved form an approximately cylindrical space between the interleaved fingers to receive a second pin   v. the second pin or the space between the fingers or both being conical in shape, tapered along the length of the tube with the small end of the taper closest to a second clamshell clamp   
           b. a similar second clamshell clamp, formed to receive a third pin to form a hinge and a fourth pin to hold the half-pipes together, with the taper of the conical fourth pin or space for the fourth pin having its small end closest to the first clamp   c. the second and fourth pins joined together such that if the clamps are moved apart along the pipes upon which they are deployed, those pins are held immovable with respect to each other and the spaces between the fingers of the clamps are forced such that the clamps are further tightened about the pipes.       
 
         [0021]    The invention also provides for a method of joining and holding two pipes of similar diameter butted end to end, comprising the steps of:
       a. applying a clamshell clamp to one pipe near the joint with its tapered fingers, if any, aligned small end toward the pipe joint   b. applying the other clamshell clamp to the other pipe near the joint with its tapered fingers, if any, aligned small end toward the pipe joint   c. inserting the second pin into the first clamshell clamp   d. inserting the connected fourth pin into the second clamshell clamp   e. sliding each clamshell clamp away from the other, roughly equidistant from the pipe joint until the connection between the second and fourth pins is taut and those pins engage the clamshell clamps&#39; half-pipes closing them to clamp each pipe where applying a clamp comprises the steps of:   f. placing one half-pipe of a clamp on the pipes   g. placing the other half-pipe on the opposite side of the pipe so that the fingers interleave, forming a pin-receiving space   h. inserting a tightening pin (the second pin of the apparatus) to temporarily hold the half-pipes over the pipe   i. inserting a hinge pin (the first pin of the apparatus) in the loops of the two half-pipes to form a hinge   j. loosening or removing the tightening pin (the second pin)   k. sliding the clamp to a desired location along the pipe   l. moving the tightening pin and clamps to force the two half-pipes to clamp the pipe.       
 
         [0034]    The method may include the additional step: performing the steps f. through l. on the second pipe where the desired location of each clamp is roughly equidistant from the pipes&#39; joint with the pin connector taut and the tightening pins causing both clamps to exert sufficient clamping force to hold their respective clamped pipe. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0035]    Referring to the drawings wherein like reference numerals indicate similar parts throughout the several views, several aspects of the present invention are illustrated by way of example, and not by way of limitation, in detail in the figures, wherein: 
           [0036]      FIG. 1  is a perspective view of a pipe clamp; 
           [0037]      FIG. 2  is a perspective view of a first clamp member; 
           [0038]      FIG. 3  is a side view of the first clamp member of  FIG. 2 ; 
           [0039]      FIG. 4  is an end view of the first clamp member of  FIG. 2 ; 
           [0040]      FIG. 5  is a perspective view of a second clamp member; 
           [0041]      FIG. 6  is a side view of the second clamp member of  FIG. 5 ; 
           [0042]      FIG. 7  is an end view of the second clamp member of  FIG. 5 ; 
           [0043]      FIG. 8  is a perspective view of the pipe clamp of  FIG. 1  with a pin inserted through joining members on the pipe clamp; and 
           [0044]      FIG. 9  is schematic illustration of a pipe clamping system. 
       
    
    
     DETAILED DESCRIPTION 
       [0045]    The detailed description set forth below in connection with the appended drawings is intended as a description of various embodiments of the present invention and is not intended to represent the only embodiments contemplated by the inventor. The detailed description includes specific details for the purpose of providing a comprehensive understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention may be practiced without these specific details. 
         [0046]      FIG. 1  illustrates a pipe clamp  10  in one aspect. The pipe clamp  10  is adapted to be placed around a tubular pipe (not shown) and secured in place over the pipe. The pipe clamp  10  can have a first clamp member  100  and a second clamp member  200  that are configured to curve around and enclose a rigid pipe (not shown) in a passage  16  formed by the first clamp member  100  and the second clamp member  200 . The first clamp member  100  and the second clamp member  200  each have a number of joining members or fingers  110  and  210  attached to top edges  120  and  220  of the first clamp member  100  and the second clamp member  200  respectively, and a number of loop members  130 ,  230  attached to bottom edges  140 ,  240  of the first clamp member  100  and the second clamp member  200 , respectively. 
         [0047]    Referring to  FIGS. 2 ,  3  and  4 , each joining member  110  can be connected to the top edge  120  of the first clamp  100  can be separated from an adjacent joining member  110  by a spacing  118 . Each joining member  110  can also be made up of a connecting portion  112  and a flange  114  such that the flange  114  connects the connecting portion  112  to the top edge  120  of the first clamp member  100 . The connecting portion  112  and the top edge  120  of the first clamp member  100  can define a slot  115  that is open at a first end at a spacing  118 . The slot  115  can end at an other end by the flange  114 . 
         [0048]    Referring to  FIG. 4 , in a preferred embodiment, each of the connecting portions  112  of the joining members or fingers  110  can be curved in a direction that is opposite to the direction of curvature of the first clamp member  100 . 
         [0049]    Referring again to  FIGS. 2 ,  3  and  4 , in a preferred embodiment, loop members  130  connected to the bottom edge  140  of the first clamp members  100  can be separated from adjacent loop members  130  by spacings  138 . Each loop member  130  can also have an aperture  132  passing through the loop member  130 . 
         [0050]    Referring to  FIGS. 5 ,  6  and  7  the second clamp member  200  can be configured similar to the first clamp member  100  with the joining members  210  attached to the top edge  220  of the second clamp member  200  and separated from adjacent joining members  210  by spacings  218 . Each joining member  210  can have a connecting portion  212  that is attached to the top edge  220  of the second clamp  200  by a flange  214 . Slots  215  can be defined between the connecting portion  212  and the top edge  220  of the second clamp member  200 . 
         [0051]    Referring to  FIG. 7 , the connecting portion  212  of the joining members  212  can be curved with the direction of curvature of the connecting portion  212  of the joining member  212  being opposite to the direction of curvature of the second clamp member  200 . 
         [0052]    Referring again to  FIGS. 5 ,  6  and  7 , loop members  230  can be provided on the bottom edge  240  of the second clamp member  200 . The loop members  230  can be separated from adjacent loop members  230  by spacings  238 . Each loop member  230  can have an aperture  232  passing through it. 
         [0053]    Referring again to  FIG. 1 , the spacings  118  between the connecting portions  112  of the joining members  110  attached to the first clamp member  100  can be sized to allow the flanges  214  of the joining members  210  attached to the second clamp member  200  to pass between these spacings  118 . In this manner, the flanges  214  of the joining members  210  attached to the second clamp member  200  can be slid through the spacings  118  until the flanges  214  lie adjacent to the top edge  120  of the first clamp member  100 . The first clamp member  100  and the second clamp member  200  can then be slid relative to each other so that each flange  214  of the joining members  210  slides through the corresponding slot  115  defined by the joining members  110  and the top edge  120  of the first clamp member  100  until the joining members  110  attached to the first clamp member  100  align with the joining members  210  attached to the second clamp member  200 , as shown in  FIG. 1 , thereby interlocking the joining members  110  attached to the first clamp member  100  and the joining members  210  attached to the second clamp member  200 . 
         [0054]    With the joining members  110  and the joining members  210  interlocked, the joining members  110  attached to the first clamp member  100  may lie across from the joining members  210  attached to the second clamp member  200  with the joining members  110  attached to the first clamp member  100  and the joining members  210  attached to the second clamp member  200  corresponding to form a generally cylindrical passage  50  running between the joining members  110 ,  210 . In one aspect, the generally cylindrical passage  50  can be slightly tapered as it runs from a first end  12  to a second end  14  of the pipe clamp  10 . 
         [0055]    Alternatively or additionally, the spacings  218  between the connecting portions  212  of the joining members  210  attached to the second clamp member  200  can be sized to allow the flanges  114  of the joining members  110  attached to the first clamp member  100  to pass through these spacings  218 . This allows the joining members  110 ,  210  to be interlocked by sliding the flanges  114  of the joining members  110  through the spacings  218 . 
         [0056]    The slots  115 ,  215  defined between the connecting portion  112 ,  212  of the joining members  110 ,  210  and the top edges  120 ,  220  of the first and second clamp members  100 ,  200  can be sized large enough so that the first clamp member  100  and the second clamp member  200  can pivot at the top edges  120 ,  220  allowing the bottom edges  140 ,  240  of the first clamp member  100  and the second clamp member  200  to be moved towards and away from each other. 
         [0057]    With the joining members  110 ,  210  interlocked, the first clamp member  100  and the second clamp member  200  can be pivoted relative to one another, around the top edges  120 ,  220  of the first clamp member  100  and the second clamp member  200 , respectively, so that the loop members  130  attached to the bottom edge  140  of the first clamp member  100  and the loop members  230  attached to the bottom edge  240  of the second clamp member  200  align with one another. Typically, the loop members  130  attached to the bottom end  140  of the first clamp member  100  will have the spacings  138  between adjacent loop members  130  positioned to correspond with the loop members  230  attached to the bottom end  240  of the second clamp member  200  and the spacings  238  between the adjacent loop members  230  on the bottom end  240  of the second clamp member  200  can be positioned to correspond to the loop members  130  on the bottom edge  140  of the first clamp member  100 . In this manner, the apertures  132 ,  232  in the loop members  130 ,  230  can align coaxially, forming a passage  60  running through the apertures  132 ,  232  of the loop members  130 ,  230  from the first end  12  of the pipe clamp  10  to the second end  14 . 
         [0058]    With the loop members  130 ,  230  aligned and forming the passage  60  with the apertures  132 ,  232  in the loop members  130 ,  230 , a shaft  70  can be inserted through the passage  60  and secured in place, thereby securing the bottom edges  140 ,  240  of the first clamp member  100  and the second clamp member  200  relative to one another. 
         [0059]      FIG. 8  illustrates the clamp  10  with a pin  80  inserted through the passage  50  formed by the joining members  110 ,  210 . With the shaft  70  inserted through the loop members  130 ,  230  and holding the bottom edges  140 ,  240  relative to one another, a pin  80  can be inserted through the passage  50  formed by the joining members  110 ,  210  to secure the top ends  120 ,  220  of the first clamp member  100  and the second clamp member  200  relative to one another. The pin  80  can force the joining members  110 ,  210  outwards and away from each other, which will thereby force the first clamp member  100  and the second clamp member  200  towards each other. 
         [0060]    In a preferred embodiment, the pin  80  is slightly tapered along its length. In another aspect, the passage  50  might be slightly tapered along its length. In yet another aspect, both the pin  80  and the passage  50  might be slightly tapered along their lengths. 
         [0061]    In one aspect, the inner surfaces of the pipe clamps may be smooth along the full length In another aspect, the inner surfaces of the pipe clamps may be concentrically ridged along the full length. Or in yet another aspect, the surface may have raised protrusions along the full length. In other aspects not limited to the descriptions above, the inner surface of the pipe clamp may be configured to enhance grip or friction with the pipe&#39;s outer surface. 
         [0062]    In operation, the pipe clamp  10  can be installed around a rigid pipe (not shown) and then clamped to the pipe. The first clamp member  100  and the second clamp member  200  can be provided on either side of the pipe so that the pipe passes through the passage  16  formed by the first clamp member  100  and the second clamp member  200 . The joining members  110  attached to the top edge  120  of the first clamp member  100  can then be connected to the joining members  210  attached to the top edge  220  of the second clamp member  200  by sliding the flanges  114  through the spacings  218  or the flanges  214  through the spacings  118 . The first clamp member  100  can then be slid relative to the second clamp member  200  so that the joining members  110  on the first clamp member  100  and the joining members  210  on the second clamp member  200  can be aligned. The first clamp member  100  and the second clamp member  200  can then be pivoted relative to one another and around the pipe so that the loop members  130  on the bottom end  140  of the first clamp member  100  and the loop members  230  on the bottom end  240  of the second clamp member  200  can align with their apertures  132 ,  232  forming the passage  60 . The shaft  70  can then be slid through the passage  60  securing the bottom edges  140 ,  240  of the first clamp member  100  and the second clamp member  200  relative to each other. The first clamp member  100  and second clamp member  200  will at this point be surrounding the pipe. The pin  80  can be inserted in the passage  50 , formed by the joining members  110 ,  210 , which can force the joining members  110 ,  210  away from each other and thereby forcing the first clamp member  100  towards the second clamp member  200  and around the pipe. 
         [0063]      FIG. 9  shows a first pipe clamp  10 A and a second pipe clamp  10 B for use in tethering the ends of two pipes  300 A and  300 B together that are temporarily joined, such as with a hammer union, to prevent the ends of the pipes  300 A and  300 B from moving apart in the event that the joint fails, such as when the pressure of the fluid passing through the pipes  300 A and  300 B causes a blowout at the joint. 
         [0064]    In a preferred method, to tether the two pipes  300 A and  300 B together, the first pipe clamp  10 A can be positioned around an end of the first pipe  300 A with the first clamp member  100 A and the second clamp member  200 A provided on either side of the first pipe  300 A. The joining members  110 A,  210 A on the first pipe clamp  10 A can then be interlocked. The first clamp member  100 A and the second clamp member  200 A can then be pivoted to enclose the first pipe  300 A until the loop members  130 A and  230 A are aligned. A shaft  70 A can then be inserted through the passage  60 A formed by the aligned apertures  132 A and  232 A of the loop members  130 A and  230 A. 
         [0065]    The second clamp  10 B can be installed on the second pipe  300 B, by placing the first clamp member  100 B and the second clamp member  200 B around the end of the second pipe  300 B and interlocking the joining members  110 B and  210 B together. The first clamp member  100 B and the second clamp member  200 B can then be pivoted relative to one another until the loop members  130 B and  230 B align and form the passage  60 B. The shaft  70 B can then be inserted through the passage  60 B securing the bottom edges  140 B and  240 B of the first clamp member  100 B and the second clamp member  200 B relative to one another. 
         [0066]    A tether  350  having a first end pin  355 A and a second end pin  355 B with a cable  352  connected between the first end pin  355 A and the second end pin  355 B can be provided. In one aspect, the first end pin  355 A and the second end pin  355 B may be tapered, increasing in diameter away from the cable  352 . The tether  350  can be used to secure the first clamp  10 A and the second clamp  10 B to the respective pipes  300 A and  300 B and to hold the ends of the two pipes  300 A and  300 B in the event of a blowout. 
         [0067]    In one aspect, the tether  350  can be used to secure the first pipe clamp  10 A and the second pipe clamp  10 B in place by sliding the cable  352  of tether  350  between the tops of the joining members  110 A,  210 A of the first pipe clamp  10 A and the joining members  110 B,  210 B of the second pipe clamp  10 B, where a space is formed. By passing the cable  352  through these spaces, the cable  352  can run through the passage  50 A formed by the joining members  110 A,  210 A of the first pipe clamp  10 A, and the passage  50 B formed by the joining members  110 B,  210 B of the second pipe clamp  10 B. The first pipe clamp  10 A and the second pipe clamp  10 B can then be slid away from each other along the first pipe  300 A and the second pipe  300 B respectively, until the larger first end pin  355 A is moved into the passage  60 A and the second end pin  355 B is moved into the passage  60 B, causing the pipe clamps  10 A,  10 B to clamp onto their respective pipes  300 A,  300 B with the cable  352  securing the ends of the pipes  300 A,  300 B relative to one another in the event of a failure of the temporary join. 
         [0068]    The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to those embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein, but is to be accorded the full scope consistent with the claims, wherein reference to an element in the singular, such as by use of the article “a” or “an” is not intended to mean “one and only one” unless specifically so stated, but rather “one or more”. All structural and functional equivalents to the elements of the various embodiments described throughout the disclosure that are known or later come to be known to those of ordinary skill in the art are intended to be encompassed by the elements of the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claim.