Abstract:
A method for coupling a conduit to a fitting. The method includes providing a fitting having a body and a passageway extending through the fitting body, inserting at least a portion of the fitting body within at least a portion of a collar, and compressing at least a portion of the collar around at least a portion of the fitting body such that the fitting body is not internally supported from within the passageway.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    This invention relates generally to fittings, and more specifically to methods and apparatus for coupling a conduit to a fitting.  
           [0002]    At least some known conduit fitting assemblies include a collar coupled to an end fitting. The end of the conduit end is received within a portion of the collar, and a portion of the end fitting is received within the conduit end. More specifically, the portion of the collar that includes the conduit end is then compressed radially inwardly such that the conduit end is compressed between the end fitting and the collar. When compressed, friction created between the collar and an outer surface of the conduit end, and friction created between an inner surface of the conduit end and the end fitting retains the conduit end within the collar.  
           [0003]    At least some known collars are threadably coupled to the conduit end fitting, while other known collars include an offset that mates with a reduced diameter portion of the end fitting when compressed to secure the collar to the end fitting. However, such conduit fitting assemblies may require an extended length to ensure a secure connection is created between the collar and the conduit end fitting. Accordingly, the cost and overall weight of the conduit fitting assembly may be increased. Furthermore, known end fitting assemblies may not include a generally uniform end fitting nipple portion outer diameter, which may increase difficulty of inserting the fitting nipple portion within the conduit end.  
           [0004]    Other known conduit end fitting assemblies include a mandrel that is inserted within a passageway defined in the end fitting to support the end fitting and to prevent partial, or complete, collapse of the passageway. Typically, a mandrel is a rigid metallic tool that is received within the end fitting. However, for complex conduit geometries, a mandrel may be an eutectic compound that is inserted within the end fitting. Mandrels may increase the labor and tooling required to produce such fitting assemblies. In addition, when the mandrel is a eutectic compound, the eutectic compound may contaminate fluid flowing through the fitting assembly.  
         BRIEF DESCRIPTION OF THE INVENTION  
         [0005]    A method is provided for coupling a conduit to a fitting. The method includes providing a fitting having a body and a passageway extending through the fitting body, inserting at least a portion of the fitting body within at least a portion of a collar, and compressing at least a portion of the collar around at least a portion of the fitting body such that the fitting body is not internally supported from within the passageway.  
           [0006]    A fitting is provided for a fitting assembly. The fitting includes a body extending between a first end and a second end. The fitting body is configured to be at least partially received within a collar. The collar is configured to be compressed around the portion of the fitting body received within the collar such that the collar is fixedly secured to the fitting. The fitting also includes a passageway extending through the body. The passageway is configured to substantially resist radial deformation when the collar is compressed radially around the fitting body such that the fitting body is not internally supported from within the passageway.  
           [0007]    A fitting assembly is provided including a conduit having a body extending between a first end and a second end, and a fitting including a body extending between a first end and a second end. The fitting body includes a passageway extending through the fitting body. The fitting first end includes a nipple portion. In addition, the fitting assembly includes a collar having a body extending between a first end and a second end. The fitting body nipple portion is at least partially received within the conduit first end. The conduit first end is at least partially received within the collar body. The collar body is compressed around the conduit first end and a portion of the fitting body such that the conduit first end is compressed between the collar body and at least a portion of the fitting body nipple portion. The passageway is configured to substantially resist radial deformation during compression of the collar body and the first conduit end such that the fitting body is not internally supported within the passageway. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]    [0008]FIG. 1 is a side view of an exemplary end fitting for use with a conduit fitting assembly;  
         [0009]    [0009]FIG. 2 is a cross-sectional view of an exemplary collar for use with a conduit fitting assembly;  
         [0010]    [0010]FIG. 3 is a cross-sectional view of a conduit fitting assembly including the end fitting shown in FIG. 1, and the collar shown in FIG. 2; and  
         [0011]    [0011]FIG. 4 is a side view of an alternative embodiment of an end fitting that may be used with the fitting assembly shown in FIG. 3. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0012]    As used herein, the term “conduit” may include any apparatus through which a fluid may be conveyed. For example, a conduit may include a tube, a pipe, a duct, a flexible hose, and/or a non-flexible hose. The above examples are intended as exemplary only, and thus are not intended to limit in any way the definition and/or meaning of the term “conduit”.  
         [0013]    [0013]FIG. 1 is a side view of an exemplary end fitting  10  for use with a conduit fitting assembly (not shown in FIG. 1). End fitting  10  includes a first end  12 , a second end  14 , a fitting portion  16 , and a nipple portion  18 . End fitting  10  also includes a first annular portion  20  having a first diameter  21 , a second annular portion  22  having second diameter  23 , a third annular portion  24  having a third diameter  25 , a fourth annular portion  26  having a fourth diameter  27 , and a fifth annular portion  28  having a fifth diameter  29 . In one embodiment, fourth diameter  27  is substantially equal to second diameter  23 .  
         [0014]    End fitting  10  has an overall length  30  measured between first end  12  and second end  14 . A central axis  32  extends through end fitting  10  from first end  12  to second end  14 . A substantially cylindrical passageway  34  extends through end fitting  10  from second end  14  to fitting portion  16  for a length  36 . In the exemplary embodiment, passageway  34  has a substantially constant diameter  38  that is smaller than first diameter  21 , second diameter  23 , third diameter  25 , fourth diameter  27 , and fifth diameter  29 . Fitting portion  16  is a distance  40  from end fitting first end  12 , and is configured to couple with a second end fitting (not shown) such that passageway  34  is in coupled fluid communication with a passageway (not shown) extending through the second fitting.  
         [0015]    End fitting first annular portion  20  has a width  42  extending between end fitting second annular portion  22  and fitting portion  16 . End fitting second annular portion  22  has a width  44  extending between first annular portion  20  and end fitting third annular portion  24 . A groove  47 , hereinafter referred to as flange groove  47 , is defined between end fitting second annular portion  22  and third annular portion  24 . Nipple portion  18  is adjacent end fitting second end  14  and extends a distance  46  from end fitting second end  14  to end fitting third annular portion  24 . Accordingly, nipple portion  18  includes fourth annular portion  26  and fifth annular portion  28 . Fifth annular portion  28  extends a distance  48  from end fitting second end  14  to fourth annular portion  26 , and fourth annular portion  26  extends a width  50  between fifth annular portion  28  and third annular portion  24 . End fitting third annular portion  24  has a width  52  extending between end fitting second annular portion  22  and fourth annular portion  26 . Nipple fifth annular portion  28  includes a plurality of projections  54  that extend outwardly therefrom and define nipple fifth diameter  29 . As will be discussed in greater detail below, projections  54  facilitate retaining end fitting nipple portion  18  within a conduit end (not shown in FIG. 1).  
         [0016]    [0016]FIG. 2 is a cross-sectional view of an exemplary collar  60  for use with a conduit fitting assembly (not shown in FIG. 2). Collar  60  includes a first end  62 , a second end  64 , a flange  66 , a radially inner surface  68 , and a radially outer surface  70 . Collar  60  extends a length  72  between collar ends  62  and  64 . In the exemplary embodiment, collar  60  is substantially cylindrical. An inner diameter  74  of collar  50  is defined by collar radially inner surface  68 , and an outer diameter  76  of collar  60  is defined by collar radially outer surface  70 . Collar  60  also includes a central axis  78  that extends through collar length  72 . Flange  66  extends generally radially inwardly from collar first end  62  for a length  79 , towards collar second end  64 . In the exemplary embodiment, flange length  79  is smaller than end fitting second annular portion width  44 , such that flange  79  can be received within flange groove  47 . Accordingly, flange  66  extends outwardly from collar first end  62  at an angle  80  relative to collar radially inner surface  68  such that flange  66  is obliquely aligned with respect to collar radially inner surface  68 . In one embodiment, angle  80  is approximately equal to 9.5° relative to radially inner surface  68 . In another embodiment, angle  80  may be between approximately 9° and 10° relative to radially inner surface  68 .  
         [0017]    Flange  66  includes a radially inner surface  82  and a radially outer surface  84 . Flange radially inner surface  82  defines an inner diameter  86  of flange  66  that is larger than end fitting second diameter  23 . In addition, flange  66  includes a flange gap  90  that is defined by flange radially outer surface  84  and collar radially inner surface  68 , and more specifically, by flange angle  80 .  
         [0018]    [0018]FIG. 3 is a cross-sectional view of a conduit fitting assembly  100  including end fitting  10 , collar  60 , and a conduit  102 . Conduit  102  includes a first end  104 , a second end (not shown), a radially outer surface  106 , and a liner  108 . A central axis  109  extends through conduit  102  between conduit first end  104  and the conduit second end. A radially inner surface  110  of conduit liner  108  defines an inner diameter  112  of conduit  102 . Conduit liner inner surface  110  also defines a passageway  114  that extends substantially through the length of conduit  102  between conduit first end  104  and the conduit second end. Conduit radially outer surface  106  defines an outer diameter  116  of conduit  102 . Conduit  102  is received within a portion of collar  60 , and end fitting nipple portion  18  is received within a portion of conduit  102 , such that conduit passageway  114  is coupled in fluid communication with end fitting passageway  34 . In the exemplary embodiment, conduit inner diameter  112  is smaller than nipple fourth diameter  27  and nipple fifth diameter  29 . In addition, in the exemplary embodiment, conduit outer diameter  116  is smaller than collar inner diameter  74 .  
         [0019]    To assemble conduit fitting assembly  100 , conduit first end  104  is inserted within a portion of collar  60  such that conduit  102  and collar  60  are substantially concentrically aligned, and such that conduit central axis  109  is substantially co-linearly aligned with collar central axis  78 . End fitting nipple portion  18  is then inserted within conduit first end  104  such that flange  66  is at least partially received in flange groove  47 , and such that end fitting  10  is generally concentrically aligned with conduit  102  and collar  60 . More specifically, end fitting central axis  32  is substantially co-linearly aligned with collar central axis  78  and conduit central axis  109 . Compressive force is then applied around at least a portion of collar radially outer surface  70  such that conduit  102  is compressed radially inwardly between end fitting nipple portion  18  and collar  60 . More specifically, a portion of conduit  102  is compressed radially inwardly between nipple fifth annular portion  28  and collar radially inner surface  68 , and a portion of conduit  102  is compressed between collar radially inner surface  68  and nipple fourth annular portion  26 .  
         [0020]    Compression of collar  60  also forces flange  66  within flange groove  47 , such that flange radially inner surface  82  contacts an outer surface  118  of end fitting second diameter portion  22 , and such that flange  66  is compressed. Compression of flange  66  causes flange gap  90  to substantially close such that flange radially outer surface  84  contacts collar radially inner surface  68 . Accordingly, when compressed, flange  66  is substantially parallel with collar radially inner surface  68 . In addition, when flange  66  is compressed flange  66  extends a length  120  from collar first end  62  towards collar second end  64 . In the exemplary embodiment, flange length  120  is approximately equal to end fitting second annular portion width  44 , such that flange  66  fits securely within flange groove  47  when compressed.  
         [0021]    Once collar  60  has been compressed, friction between collar radially inner surface  68  and conduit radially outer surface  106  facilitates retaining conduit first end  104  within collar  60  such that first end  104  is fixedly secured to collar  60 . In one embodiment, conduit radially outer surface  106  includes a wirebraid (not shown) that facilitates retaining conduit first end  104  within collar  60  such that first end  104  is fixedly secured to collar  60 . In addition, friction between projections  54  and conduit liner inner surface  110  facilitates retaining end fitting nipple portion  18  within conduit first end  104  such that end fitting nipple portion  18  is fixedly secured within conduit first end  104 . Furthermore, when collar  60  has been compressed, flange  66  facilitates retaining a portion of end fitting  10  within collar  60  such that end fitting  10  is fixedly secured to collar  60 . Once conduit fitting assembly has been assembled, conduit passageway  114  is coupled in fluid communication with end fitting passageway  34  and is substantially sealed with respect to end fitting passageway  34 , such that fluid does not leak from conduit fitting assembly  100 . More specifically, compression of conduit  102  between fourth annular portion  26  and collar radially inner surface  68  facilitates sealing conduit fitting assembly  100  to facilitate preventing fluid flow and/or leakage between conduit liner inner surface  110  and the radially outer surfaces of fitting nipple portion  18 .  
         [0022]    [0022]FIG. 4 is side view of an alternative embodiment of an end fitting  200  that may be used with a conduit fitting assembly, such as conduit fitting assembly  100  (shown in FIG. 3). End fitting  200  includes a first end  202 , a second end  204 , a fitting portion  206 , and a nipple portion  208 . End fitting  10  also includes a first annular portion  210  having a first diameter  212 , a second annular portion  214  having second diameter  216 , a third, annular portion  218 , and a fourth annular portion  220  having a fourth diameter  222 .  
         [0023]    End fitting  200  has an overall length  224  measured between first end  202  and second end  204 . A central axis  226  extends through end fitting  200  from first end  202  to second end  204 . A substantially cylindrical passageway  228  extends through end fitting  200  from second end  204  to fitting portion  206  for a length  230 . Fitting portion  206  is a distance  232  from end fitting first end  202 , and is configured to couple with a second end fitting (not shown) such that passageway  228  is in coupled fluid communication with a passageway (not shown) extending through the second fitting.  
         [0024]    First annular portion  210  has a width  234  extending between end fitting second annular portion  214  and fitting portion  206 . End fitting second annular portion  214  has a width  236  extending between first annular portion  210  and end fitting third annular portion  218 . End fitting third annular portion  218  has a width  238  extending between second annular portion  214  and end fitting fourth annular portion  220 . End fitting third annular portion  218  has a third-diameter  240  adjacent second annular portion  214  that decreases along third annular portion width  238  as third annular portion  218  approaches fourth annular portion  220 . The diameter of third annular portion  218  is substantially equal to fourth diameter  222  at the intersection of third annular portion  218  and fourth annular portion  220 . End fitting fourth annular portion  220  extends a distance  240  from third annular portion  218  to end fitting second end  204 .  
         [0025]    End fitting nipple portion  208  is adjacent end fitting second end  204  and extends a distance  242  from end fitting second end  204  to end fitting third annular portion  218 . Accordingly, nipple portion  208  includes fourth annular portion  220 . End fitting nipple portion  208  is configured to be received within a conduit end, as described above in reference to end fitting  10  (shown in FIG. 1) and conduit fitting assembly  100  (shown in FIG. 3). Nipple fourth annular portion  220  includes a plurality of projections  244  that extend outwardly therefrom and define nipple fourth diameter  222 . Projections  244  facilitate retaining end fitting nipple portion  208  within the conduit end.  
         [0026]    Compressive force is applied radially inwardly to a collar (not shown) to secure end fitting  200  to the collar. Unlike collar  60  (shown in FIG. 2) the collar is a substantially right cylinder, and is known as a straight collar. The compressive force may cause deformation to at least some known end fittings such that a fluid passageway, such as passageway  228 , within the end fitting may partially collapse, thereby possibly restricting fluid flow through the passageway. End fitting  200  includes a minimum thickness  248  between end fitting radially inner wall  229  and second diameter  216 , between end fitting radially inner wall  229  and an outer surface  250  of third annular portion  218 , and between end fitting radially inner wall  229  and fourth diameter  222 . More specifically, a thickness of at least minimum thickness  248  extends along second annular portion fifth length  236 , third annular portion sixth length  238 , and fourth annular portion seventh length  240 . When compressive force is applied radially inwardly along second annular portion fifth length  236 , third annular portion sixth length  238 , and fourth annular portion seventh length  240 , minimum thickness  248  provides sufficient strength to support passageway  228  such that passageway  228  substantially resists radial deformation beyond design requirements, and such that end fitting  200  is not supported from within passageway  228 . In addition, in one embodiment minimum thickness  248  facilitates preventing radial deformation of passageway  228  greater than 0.002 inches. In another embodiment, thickness  248  facilitates preventing radial deformation of passageway  228  greater than 0.0005 inches. In yet another embodiment, minimum thickness  248  facilitates preventing radial deformation of passageway  228  greater than 0.001 inches.  
         [0027]    The above-described conduit fitting assembly is cost-effective and highly reliable for coupling a conduit to a fitting. The assembly permits a lightweight and low-cost collar to be precision mated to an end fitting without the use of a threaded connection. More specifically, the assembly allows the use of an end fitting that is shorter, thereby decreasing the assemblies weight and cost, and increasing the amount of conduit that is flexible. The assembly may also facilitate coupling a conduit to a fitting without using a mandrel. As a result, the assembly facilitates coupling a conduit to a fitting in a cost-effective and reliable manner.  
         [0028]    Exemplary embodiments of conduit fitting assemblies are described above in detail. The assemblies are not limited to the specific embodiments described herein, but rather, components of each assembly may be utilized independently and separately from other components described herein. Each fitting assembly component can also be used in combination with other fitting assembly components.  
         [0029]    While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims.