Abstract:
A hydraulic coupling for use in undersea drilling and production operations is disclosed, having a male member with radially extending projections or fins configured to be received in a female member having corresponding grooves in its receiving chamber. Relative rotation of the members urges the male member inwardly and preferably compresses axially a metal seal between the leading face of the male member and an internal shoulder. This preloads the seal before the coupling is pressured up with hydraulic fluid. The rotation of the male member may be done manually or by remote actuation.

Description:
This application is a continuation of Ser. No. 08/308,116 filed Sep. 16, 1994, abn. 
    
    
     BACKGROUND OF THE INVENTION 
     1. FIELD OF THE INVENTION 
     This invention relates in general to hydraulic couplings, and specifically to hydraulic couplings used in undersea drilling and production applications. More particularly, this invention involves a hydraulic coupling configured to urge the members together and axially compress a ring-shaped seal in the female member upon connection of the members. 
     2. DESCRIPTION OF THE RELATED ART 
     Subsea hydraulic couplings are old in the art. The couplings generally consist of a male member and a female member with sealed fluid passageways connected therebetween. The female member generally is a cylindrical body with a relatively large diameter longitudinal bore at one end and a relatively small diameter longitudinal bore at the other. The small bore facilitates connections to hydraulic lines, while the large bore seals and slidingly engages the male member of the coupling. The male member includes a cylindrical portion at one end having an outer diameter approximately equal to the diameter of the large bore of the female member of the coupling. The male member also includes a connection at its other end to facilitate connection to hydraulic lines. When the cylindrical portion of the male member is inserted into the large bore of the female member, according to various embodiments of the device, fluid flow is established between the male and female members. 
     In the past, various types of seals have been used between the male and female members of the coupling. For example, U.S. Pat. No. 4,694,859 discloses an undersea hydraulic coupling with a hollow, ring-shaped metal seal that is pressure energized to seal radially between the female member and the outer surface of the male member. Similarly, in U.S. Pat. No. 4,754,470 two metal seals are positioned between the circumference of the male member and central bore of the female member. 
     Another type of seal in an undersea hydraulic coupling is disclosed in U.S. Pat. No. 4,637,470. This patent shows a seal that is V-shaped in cross section and is compressed axially between the end or leading face of the male member and a shoulder in the bore of the female member. Belleville washers are used to provide a force between the members to maintain the seals in tight contact. This force is necessary to avoid leakage of hydraulic fluid if the members are slightly separated. 
     During use of hydraulic couplings, fluid pressure is exerted between the male and female members in such a way as to tend to separate them. The male and female members are typically attached to opposing manifold plates which are held together by bolts or hydraulic members attached to the plates. The male members are commonly attached to one plate while the female members are attached to an opposing plate so as to face the male members and align with them. Typically, groups of 10 or more coupling members are attached to each manifold plate. The manifold plates tend to warp or rock when coupling members are pressured up, thus causing the coupling members to separate slightly. 
     In the prior art, various approaches have been suggested to secure the male and female members of the coupling together. For example, lock sleeves have been used in so-called quick release couplings. In those type of couplings, a sleeve is pulled back from one member of the coupling to lock or release the coupling members together. Typically a ball and groove configuration is used. 
     Another approach, as disclosed in U.S. Pat. No. 4,637,470, uses Belleville washers to provide a force urging the numbers together. 
     Still another approach is that of U.S. Pat. No. 4,915,419 to Robert E. Smith III. This patent shows an apparatus for locking together simultaneously one or more male and female coupling members using a sliding lock plate. In the locked position, passages in the lock plate are configured to engage the circumference of the male and female coupling members and restrict axial movement of the members. 
     SUMMARY OF THE INVENTION 
     The present invention resides in a hydraulic coupling of the foregoing type, including male and female members for fluid communication therebetween and a ring-shaped seal for sealing the junction between the coupling members. To lock the members together, and ensure that the seal is axially compressed to form a fluid tight seal between the members, the male member is cammed axially inwardly into the female member bore by rotation of the male member with respect to the female member. At least two fins or projections extend radially outwardly from the body of the male member and are captured in a groove in the female member bore which, during relative rotation of the members, urges the male member inwardly and axially compresses a ring-shaped seal in the bore. Preferably, the seal is a metal seal with a V-shaped cross section which is axially compressible between the face of the male member and a shoulder in the bore of the female member. 
     The male member contacts the seal before it is rotated, and then as it is rotated approximately 90 degrees, the male is brought further into the female member bore to slightly press against the metal seal and compress it. The male member may be rotated manually or actuated by mechanical means such as a cam. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a section view of a male member of a coupling according to a preferred embodiment of the present invention. 
     FIG. 2 is a section view of a female member of a coupling in a preferred embodiment of the invention. 
     FIG. 3 is a section view of a male member partially inserted into the female member of a coupling, before it is rotated to compress the seal. 
     FIG. 4 is a section view of a male member fully inserted into the female member with the seal compressed according to a preferred embodiment of the present invention. 
     FIG. 5 is a cross-section view of the coupling shown in FIG. 3 before the camming surfaces are rotated. 
     FIG. 6 is a cross-section view of the coupling shown in FIG. 4 after the camming surfaces are rotated. 
     FIG. 7 is a perspective view of the male and female members of the coupling. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The coupling of the present invention includes a male member  10  and a female member  20 . As shown in FIG. 1, the male member  10  comprises a handle or flange  42 , a tapered shoulder  43  and a cylindrical probe wall  44 . In a preferred embodiment, the probe wall further includes a first shoulder  46 , a reduced diameter probe wall  47 , a second tapered shoulder  48  and a leading face  45 . 
     The male member includes an internal bore  32  extending therethrough. At one end of the bore is a threaded passage  50  for connection to a hydraulic line. Adjacent and inboard of the threaded section is a cylindrical passageway  51  extending longitudinally within the male member body and terminating at valve seat  62  which is an inclined shoulder. Adjacent the valve seat is cylindrical passage  66  having a reduced diameter. 
     As shown in FIG. 1, valve assembly  61  is slidably received within the central bore  32  of the male member. The various parts of the valve assembly of the male member are valve head  60  with apertures  63  extending therethrough, and valve face  64  which is conical in shape and dimensioned to seat within the valve seat  62  at the end of the male member bore. Extending from the valve face  64  is a valve actuator  65  which is cylindrical in shape and extends along the longitudinal axis of the male member. The valve actuator  65  is located at the apex of the conical valve face. Helical valve spring  71  is used to urge the valve face  64  into a closed position against valve seat  62 . The helical valve spring is located within the cylindrical passageway  51  and anchored at hollow spring collar  72  which is held in place by collar clip at the inner surface of the cylindrical passageway  51 . The opposite end of the helical valve spring  71  is in contact with the valve assembly, urging it into a closed position against the valve seat. 
     Extending radially outwardly form the probe wall  44  are projections or fins  49  and  52 . In a preferred embodiment, two projections or fins are used. However, as will be apparent to those skilled in the art, additional projections or fins may be used to cam the male member axially into the female member bore or receiving chamber, as will be described in more detail below. Preferably, projection  49  is 180 degrees removed from projection  52 , although the projections may be aligned or spaced as desired. As shown in FIG. 1, a rod  40  may be inserted into the handle  42  on each side of the handle with threads  41  or other attachment means. Such means may be used to manually rotate the male member when it is inserted into the female member. Other means for rotation may be used, such as mechanical means or cams. 
     Now turning to FIG. 2, a preferred embodiment of the female member of the present invention is shown. The female member  20  is attached to a manifold plate  21  so as to face the male member and align with it. The female member may be attached to the manifold plate using various means, such as set screws or threads. Techniques for attaching the member to a manifold plate are well known to those skilled in the art. The female member  20  comprises a handle  80 , central bore  87  and a valve assembly  82 . The handle  80  is optionally threaded to the manifold plate with threads  90 . The female member also includes a shoulder  91  which is adjacent the threaded portion of the handle are the main cylindrical body  110 , which terminates at female member face  93 . 
     Central bore  87  has several variations in its diameter, as it extends through the body of the female member  20 . At a first or outer end of the central bore is a threaded internal passageway  95  for connection to a threaded hydraulic line. The threaded portion  95  of the central bore terminates at cylindrical passageway  96  slidably receiving valve assembly  82 . Cylindrical passageway  96  terminates internally at valve seat  97  for seating the valve face  86 . Inboard of the valve seat  97  is narrowed bore  98 . 
     The valve assembly  82  of the female member is substantially similar to the valve assembly of the male member and comprises a hollow valve body or head  85 , with apertures  112  extending therethrough. Adjacent the cylindrical body is valve face  86  which is generally conical in shape for seating at the valve seat  97 . Valve actuator  115  extends from the apex of the conical valve face and extends through passageway  98 . To urge the female member valve assembly into the closed position, a helical valve spring  119  is mounted between the shoulder of the valve head  85  and spring collar  120  having collar clip  121  within passageway  96 . The valve assembly  82  of the female member and valve assembly  61  of the male member are generally identical in components and function. When each valve is an open position wherein the mutually opposed faces of the valve actuators  65  and  115  are in contact with each other, the helical valve springs exert insufficient force to keep the check valves in the closed position. The passageways for fluid communication between the male and female members then open to allow fluid flow between the members. 
     The female member, as shown in FIG. 2, further comprises a receiving chamber  107  configured to receive the male member therein. In a preferred embodiment, the receiving chamber  107  includes several variations in its diameter. Adjacent the face  93  of the female member, the first end  100  of the receiving chamber has its largest diameter. Positioned on each side of the first end  100  of the receiving chamber are axially slots  84  and  88  configured to receive the radial projections  49  and  52  of the male member. Slots  84  and  88  extend between the channel  83  in the female member and the face  93 . Projections  49  and  52 , as well as the groove  83  may be the same or similar to an interrupted stub acme type thread. The receiving chamber  107  further includes a shoulder  102  and a second diameter  103  which is preferably narrower than the first diameter  100 . In a preferred embodiment, the second section  103  includes a circumferential groove  109  for receiving a seal therein, which preferably is an elastomeric  0 -ring  108 . This seal serves as a back up seal to the metal seal  106  as will be described below. 
     The receiving chamber further includes shoulders  99  and  106  for annular ring-shaped seal  105 . Annular seal  105  preferably is metal seal having a V-shaped cross section which is axially compressible. As shown in FIG. 2, one leg of the V-shaped seal seats against shoulder  99  and the opposing leg is configured to seal against the leading face  45  of the male member. In a preferred embodiment, the seal is retained in the female member bore with use of retainer  104  which optionally may be threaded to the second diameter  103  of the female member receiving chamber. However, other means of retaining the seal in the female bore may be used, such as a lock ring captured in an internal groove in the receiving chamber. 
     Although a metal seal with a V-shaped cross section is shown in a preferred embodiment, it will be recognized to those skilled in the art that other types of axially compressible seals may be used. For example, a C-ring seal may be used to seal axially by compression against the face  45  of the male member, or against another surface such as a shoulder on the male member body. Alternatively, elastomeric seals may be used to seal against the leading face of the male member. The seal should be compressible axially to enhance its sealing effect. Therefore, seals having an internal cavity which may be pressure energized and compressible axially are preferred. 
     Now referring to FIG. 3, the male member is shown partially inserted into the female member according to a preferred embodiment of the present invention. In FIG. 3, radial projection or fin  49  has been fully inserted down axial slot  84  and radial projection or fin  52  has been inserted down slot  88 . At this point, the male member may be rotated 90 degrees while the projections  49  and  52  are within groove  83 . In FIG. 3, the end of the male member, leading face  45 , has touched seal  105 . 
     Now referring to FIG. 4, the male member has been rotated 90 degrees while projections  49  and  52  are within groove  83 . At this point, the leading face  45  of the male member has compressed the seal  105  axially to preload the seal. The seal is compressed between the leading face  45  of the male member and the shoulder  99  in the female receiving bore. 
     In FIG. 5, a cross section of the male and female members is shown is the same position as FIG.  3 . Prior to rotation of the male member, projection  49  is within slot  84 , and projection  52  is within slot  88 . At this point, the male member may be rotated with both projections in groove  83 . In FIG. 6, the members have been rotated 90 degrees relative to each other. This locks the male member to the female member, and axially compresses the seal  105  as described above. 
     In FIG. 7, a perspective view of the male and female members is shown. The male member  10  may be inserted into the female member receiving chamber  107  so that fins or radial projections  49  and  52  align with slots  84  and  88 , respectively. Then, when the projections reach groove  83 , the male member may be rotated to secure it to the female member and axially compress seal  105 . 
     Although variations in the embodiment of present invention may not each realize all of the advantages of the invention, certain features may become more important than others in various applications of the device. The invention, accordingly, should be understood to be limited only by the scope of the appended claims.