Abstract:
A quick connector fitting assembly is provided which includes a fitting which releasably connects to a well casing for providing an interface for the attachment of various types of well related equipment. The quick connector fitting connects using fasteners to a lip or groove formed on the casing. The fasteners can easily connect or disconnect from the groove or lip facilitating the quick connection and disconnection of the fitting from the casing.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     More than one reissue application has been filed for the reissue of U.S. Pat. No. 6,199,914. The reissue applications are reissue application Ser. No. 10/325,047 filed on Dec. 20, 2002 and the present reissue application which is a divisional of reissue application Ser. No. 10/325,047. 
     This application claims priority and is based on Provisional Application 60/088,586 filed on Jun. 9, 1998. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention relates to quick connect assemblies including quick connector fittings which quickly and releasably connect to a well casing for providing an interface for attaching well related equipment such as blowout preventors to the casing. 
     Fittings, such as drilling flanges, are currently used to provide an interface to well casings for mounting various equipment such as blowout preventors. A conventional fitting, such as a drilling flange, is threaded onto the casing until a shoulder within the drilling flange makes contact with the casing mouth. An elastomeric O-ring seals the drilling flange/casing interface. Once such a drilling flange is mounted on a casing, it is difficult to remove. Consequently, in many instances, the drilling flange remains permanently on the casing. As a result, on the field where multiple drilling operations may be going on at once, a separate drilling flange is required for each casing. This can be expensive. 
     Another problem with these flanges is that their orientation with respect to the casing cannot be accurately predetermined. The orientation depends on how tight the flange is threaded on the casing. This shortcoming poses a problem in situations where the equipment to be attached requires a specific orientation relative to the casing. 
     As such, a quick connect assembly is needed which provides for the easy installation and removal of a quick connector fitting so as to allow the fitting to be used on multiple casings in the field and which allows the fitting to be oriented to any desired position relative to the casing. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to quick connect assemblies allowing for the quick and releasable connection of a quick connector fitting to a well casing for providing an interface for the attachment of well related drilling equipment such as blowout preventors. In a first embodiment, a male receiver is coupled to the casing. The receiver has an annular lip formed on its outer surface near its upper open end or mouth. The annular lip has a lower surface which slopes upward in a radially outward direction. A quick connector fitting has a first cylindrical section which tapers to a smaller second cylindrical section. A flange extends radially from an upper end of the smaller cylindrical section. The flange provides the interface for attaching well related equipment. The larger cylindrical section of the fitting is slid over the mouth of the male receivers. Threaded openings are formed radially through the larger section of the fitting and are arranged circumferentially around the fitting. Lock screws are threaded through the openings to engage the lower sloping surface of the annular lip male receiver. As the lock screws are tightened, the lip sloping surface guides them downward thereby causing the fitting to seat and lock on the male receiver mouth. To remove the fitting, the lock screws are loosened. 
     In another embodiment, a quick connector fitting is used having an annular lip formed on its inner surface. A flange extends from an upper end of the fitting to provide the interface for attachment of the various well related equipment. The fitting lower end is slid over the casing head such that a lower surface of the annular lip is seated on the mouth of the casing. An annular groove is formed circumferentially around the outer surface of the fitting near the fitting lower end. The annular groove has a lower surface that slopes downward in a radially outward direction. A retainer slip, preferably a four piece retainer slip, having an upper and a lower annular lip is used to secure the fitting to the casing. The upper lip engages the groove, while the lower lip engages the outer surface of the casing. Teeth are formed on the face of the lower retainer slip lip that engages the casing. A clamp surrounds the retainer slip. As the clamp is tightened, it provides radial forces on the retainer slip causing the teeth formed on the lower lip to engage the casing outer surface and thus fix the position of the retainer slip relative to the casing. As the clamp is further tightened, the retainer slip upper lip engages the lower sloping surface of the groove formed on the outer surface of the fitting and causes the fitting to move downward against the casing. As a result, the annular lip formed on the inner surface of the fitting sits tightly against the casing mouth. 
     In yet a further embodiment, an annular bushing is threaded on the outer threads formed on the casing. Preferably the bushing is threaded downward about ¼ inch±⅛ inch from the casing mouth. An annular groove is formed on the outer surface of the bushing. The groove has an upper surface which slopes upward in a radially outward direction. A fitting is then fitted over the casing and the bushing. The fitting has an inner shoulder which sits on the mouth of the casing. On its opposite end, the fitting forms a flange for providing an interface for the well related equipment. Fasteners are threaded radially through the fitting to engage the upper surface annular groove. The sloping upper surface guides the fasteners downward thereby causing the fitting to tightly seat on the mouth of the casing and to lock on the bushing and thereby on the casing. Lock nuts may be threaded on the fasteners from the ends opposite the ends engaging the groove on the bushing. These lock nuts are threaded until they engage the outer surface of the fitting providing a radially outward force on the fasteners preventing them from loosening from the fitting. 
     In another embodiment an annular casing head is coupled to the casing. The casing head can be threaded directly to the casing or may be coupled to the casing using a coupling. An annular groove is formed on the outer surface of the casing head. The annular groove has an annular upper surface and an annular base. 
     A quick connector fitting is mated to the casing head. The quick connector fitting has a flange that extends from an upper end of the fitting for providing an interface for connecting well related equipment. 
     An annular drilling flange nut is threaded on the lower outer surface of the quick connector fitting. Load key bolts are fitted through radial openings formed on the flange nut. A retainer is used to retain each bolt on the flange nut. A preferably arc-shaped load key located inside the flange nut is threadedly engaged by each load key bolt. As a load key bolt is turned it causes its corresponding load key to translate radially and into the groove formed on the outer surface of the casing head. The flange nut is then further torqued causing the load keys to contact and apply a force against the upper surface of the annular groove on the casing head. As result, a downward force is applied by the flange nut on the quick connector fitting causing the quick connector to further sit on the mouth of the casing head forming a tight connection. 
     With any of the above described embodiments, a wear bushing may be fitted such that it provides a protecting lining to the inner surface of the casing head and a portion of the quick connector inner surface extending above the casing head. Moreover, with all of these embodiments, the quick connector fittings are preferably fastened to a groove. As a result, the fittings can be oriented to any position over the casing mouth prior to being quickly and releasably connected to the casing. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is an exploded cross-sectional view of a quick connector assembly including a male receiver coupled to a well casing and a quick connector fitting. 
         FIG. 1B  is a cross-sectional view of the assembled quick connector assembly shown in  FIG. 1A . 
         FIG. 2A  is a partial cross-sectional view of an alternate embodiment quick connector. 
         FIG. 2B  is a partial cross-sectional view of the quick connector shown in  FIG. 2A  prior to the tightening of a slip retainer clamp. 
         FIG. 2C  is a partial cross-sectional view of the quick connector shown in  FIG. 2A  with the quick connector body welded to the casing. 
         FIG. 3  is a cross-sectional view of an alternate embodiment quick connector assembly incorporating a bushing. 
         FIG. 4A  is an exploded cross-sectional view of an alternate embodiment quick connector assembly prior to the mounting of the quick connector fitting on to the casing head. 
         FIG. 4B  is an enlarged cross-sectional view of the coupling member of the assembly shown in  FIG. 4A  coupling the casing head to the casing. 
         FIG. 4C  is an enlarged cross-sectional view of the drilling flange nut of the assembly shown in  FIG. 4A . 
         FIG. 4D  is another cross-sectional view of the drilling flange nut shown in  FIG. 4C . 
         FIG. 4E  is a cross-sectional view of the assembled quick connector assembly shown in  FIG. 4A . 
         FIG. 4F  is an enlarged cross-sectional view of the drilling flange nut of the assembly shown in  FIG. 4E . 
         FIG. 5A  is an exploded cross-sectional view of another embodiment quick connector assembly. 
         FIG. 5B  is a partial enlarged cross-sectional view of the casing head of the assembly shown in  FIG. 5A  threaded to a casing. 
         FIG. 5C  is a cross-sectional view of another embodiment quick connector fitting assembly. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     This invention relates to quick connect assemblies which include a quick connector fitting (also referred to herein as a “quick connector”) that can be mounted quickly on a well casing providing an interface for the mounting of well related equipment such as blow out preventors (“BOP”). The quick connector fittings may be used and re-used on many different casings. 
     In a first embodiment, the quick connect assembly comprises a quick connector fitting  10  and a male receiver  12 . The quick connector fitting  10  releasably connects to the male receiver  12  which is coupled to a well casing  14  ( FIGS. 1A and 1B ). The casings typically have a diameter of 13-⅜ inches. The male receiver is typically connected to the casing using a coupling  16 . The coupling is an internally threaded cylindrical member. One end of the coupling is threaded to the external casing threads. The male receiver is then torqued to inner threads on the coupling other end. 
     The male receiver is typically a tubular member. The male receiver has a first end or mouth  18  for connecting with the quick connector fitting and a second end  20  for threading on the coupling. Two parallel annular lip protrusions are formed on the outer surface of the male receiver near it first end ( FIGS. 1A and 1B ). The first or upper lip  22  is formed around the mouth of the male receiver. The upper lip has an upper surface  19  that slopes downward in a radially outward direction. The upper lip also has a lower surface  23  that slopes upward in a radially outward direction. The second or lower lip  24  is formed below and spaced apart from the upper lip. An annular groove  26  is formed between the two lips. 
     The coupling  16  is threaded to the casing  14 . The male receiver is then torqued to the coupling. The male receiver may be torqued to the coupling using conventional tools such as tongs (not shown). Once the male receiver is torqued in place, the quick connector is fitted over the male receiver. The quick connector has a first larger cylindrical section  50  which tapers via a tapered section  52  to a second smaller cylindrical section  54  ( FIG. 1A ). A flange  56  is formed around the mouth of the second section to allow for the connection of a BOP or other well related equipment. The BOP or other well related equipment may be connected to the flange prior to installation of the quick connector to the male receiver. 
     The larger cylindrical section of the quick connector is placed over the male receiver such that its tapered section contacts and mates with the sloping upper surface  19  of the upper lip  22  at the mouth of the male receiver. At least two internally threaded holes  58  are formed circumferentially on the larger cylindrical section of the quick connector. When in position over the male receiver, the holes  58  are aligned with an upper portion of the groove  26  formed between the lips on the male receiver ( FIG. 1B ). Lock down screws  60  are then threaded through the holes and engage the lower sloping surface  23  of the upper lip. As the lock down screws are threaded farther, they ride on the sloping lower surface of the upper lip pulling the quick connector tighter against the mouth of the male receiver. 
     Preferably, two annular grooves  28  are formed on the inner surface of the first cylindrical section above the threaded holes  58 . A pressure or mechanically energized seal  30  is fitted in each groove. A single groove fitted with a single seal may suffice. When the quick connector is mounted on the male receiver, the seals  30  also contact the outer surface of the upper lip of the male receiver. As such, the seals form a seal against the upper lip as well as against the inner surface of the first cylindrical section of the quick connector fitting. Alternatively, the grooves  28  may be formed on the outer surface of the upper lip of the male receiver instead of the quick connector first section inner surface. The seals  30  are then seated on the grooves such that when the fitting is positioned over the male receiver, the seals will again seal against the inner surface of the first section of the quick connector and against the upper lip of the male receiver. Alternatively, the groove(s) and seal(s) may be positioned so that the seal(s) seal against the male receiver lower lip and the inner surface of the first cylindrical section of the quick connector. In a further embodiment, a seal or multiple seals may be used to form a seal against the inner surface of the quick connector and the male receiver upper lip while a second seal or second set of seals may be used to form a seal between the quick connector and the male receiver lower lip. 
     In an alternate embodiment, a quick connector fitting  62  is used that fits directly over the outer casing  14  ( FIG. 2A ). This quick connector consists of a cylindrical body  64 . An inner annular lip  66  is formed on the inner surface of the cylindrical body. An outer annular flange  68  is formed on the upper end of the cylindrical body. The upper flange serves as the connection interface with the BOP or other well related equipment. An annular groove  72  is formed on the outer surface of the cylindrical body near the body lower end ( FIG. 2B ). In cross-section, the groove has an upper surface  74 , a base  76  parallel to the longitudinal axis of the body and a lower surface  78  that slopes downward in a radially outward direction. 
     One, but preferably two, spaced apart annular grooves  80  are formed on the inner surface of the body below the inner annular lip ( FIG. 2A ). These grooves are designed to accommodate pressure or mechanically energized seals (not shown). In an alternate embodiment, an injection fitting  82  and a pressure relief fitting  84  are fitted in the wall of the body such that they extend from the outer surface of the body to an inner groove. The injection fitting and the pressure relief fitting should be spaced preferably 180° apart. An injection and a pressure relief fitting may be incorporated for each of the inner grooves. 
     The quick connector is slid over the outer surface of the casing  14  until the lower face  70  of the inner lip  66  rests against the mouth  86  of the casing. In the embodiment where the inner annular grooves  80  are fitted with seals, the seals must be fitted in the grooves prior to the installation of the quick connector over the casing. 
     A retainer slip  88  is fitted over the quick connect. The retainer slip is preferably in four pieces, each forming a 90 degree arc. However, a two or more piece retainer slip may also be used. The retainer slip consists of a lower annular lip  90  extending radially inward. Teeth  92  are formed on the inner surface of the lower annular lip. The retainer slip also has an upper inwardly extending annular lip  94  that has a shape complementary to the shape of the groove  72  formed on the outer surface of the quick connector body. As such, the lower surface  96  of the retainer slip upper lip slopes downwardly in a radially outward direction such that it is complementary to the bottom sloped surface  78  of the annular external groove formed on the quick connector body. 
     A slip retainer clamp  98  is clamped around the retainer slip so as to hold all the retainer slip pieces in place. As is apparent to one skilled in the art, it may be preferable to place the retainer slip and clamp over the casing prior to the placement of the quick connector body over the casing. In this regard, when the body is fitted over the casing, the slip may be easily moved over the quick connector body and clamped into place. 
     Initially, the clamp is tightened just enough to hold the retainer slip pieces in place as shown in  FIG. 2B . When this occurs the tip portion  100  of the retainer slip upper lip is in contact with the lower sloped surface  78  of the groove formed on the body outer surface. As the clamp is further tightened, the teeth  92  formed on the inner surface of the lower lip of the retainer slip bite onto the outer surface of the casing  14  fixing the relative position between the casing and the retainer slip. As the clamp is further tightened, it causes the lower sloped surface  96  of the upper lip of the slip to attempt to travel up the lower sloped surface  78  of the external groove. As a result, the retainer slip, which is now fixed relative to the casing, causes the quick connector body to move downward and therefore the body inner lip lower surface  70  to tightly engage the mouth  86  of the casing. 
     If the body has injection and pressure relief fittings, a sealing material  81  may be injected into the annular grooves through the injection fittings  82  until it is relieved through the pressure relief fittings  84  to form a seal between the casing and the connector. 
     A production or inner casing  102  is always fitted within the casing  14  (i.e., the outer casing) forming an annulus  104  therebetween ( FIG. 2C ). In many situations, after drilling is completed, a predetermined amount of cement is pumped down the production casing until it exits the lower end product on casing and comes around filling and sealing the annulus. 
     For proper sealing, the Department of Oil and Gas (“DOG”) requires that the annulus is completely filled with cement. As such, enough cement must be pumped to fill the annulus If more cement than required to fill the annulus is pumped, the cement will stay within the bottom of the production casing creating a blockage. As such, operators are inclined to be conservative in the amount of cement pumped into the production casing. As a result, sometimes the amount of cement pumped may be insufficient and does not fill the annulus completely. In these situations, the DOG permits the use of an automatic casing hanger  106 —or with a pack-off hanger (not shown) or with a mandrel casing hanger (not shown)—fitted within the quick connector as a supplement for sealing the annulus. Automatic casing hangers, pack-off hangers and mandrel casing hangers are well known in the art. When a hanger is used for sealing, the quick connector becomes a permanent fixture of the casing and thus, cannot be used with another casing. For economic purposes, however, it is recommended that the retainer clamp  98  and retainer slip  88  are removed so that they can be re-used. In their stead, the lower edge  108  of the quick connector body is welded to the outer casing. 
     In a further embodiment, an annular bushing  110  is threaded hand tight on the outer threads  111  formed on the outer surface of the casing head  112  ( FIG. 3 ). The casing head is coupled to the open end of a casing (not shown), preferably by threading. The outer bushing is preferably threaded down a distance  116  of about ¼ inch±⅛ inch from the casing head mouth  120 . A circumferential groove  129  is formed on the outer surface of the bushing. The groove has an upper surface  146  that slopes upward in a radially outward direction. A quick connect fitting  124  is fitted over the bushing and the casing head. 
     The quick connector fitting has an upper and a lower section. The lower section defined by an annular lip wall  128  which defines a first opening with a diameter slightly larger than the bushing outer surface diameter. At least two internally threaded holes  126  are defined circumferential through the wall  128 . A second opening  132  is defined in the upper section of the fitting. The second opening concentric to and in communication with the first opening and has a diameter preferably equal to the inner diameter of the mouth of the casing head. A flange  134  is formed at the mouth  136  of the upper section for mating with a BOP or other well related equipment. An internal annular shoulder  138  is formed at the interface between the upper and lower sections of the flange member An annular groove  140  is formed on the shoulder to accommodate a pressure or mechanically energized seal  141 . 
     The fitting is fitted over the bushing and rotated to a desired position. When the flange is fitted over the casing head, the seal sits on the mouth  127  of the casing head. When the fitting is seated on the casing head mouth, the threaded hole  126  centers will be located at a level aligned with an upper portion of the bushing circumferential groove. Lock down screws  142  having a threaded head  145  are then threaded through the threaded holes. The lock down screw heads have a tip portion  144  that is frusto-conical in shape having a frusto-conical surface  143 . As the lock down screws are threaded into the holes their tip portions first engage the sloping upper surface  146  of the bushing groove. As they are further threaded on the fitting they ride against the groove upper sloping surface pulling the quick connector fitting further downward and creating a tight seal between the fitting shoulder, the seal, and the mouth of the casing head. Consequently, the fitting is locked on the bushing and thereby on the casing head. Because the fitting locks against a groove (i.e., the bushing groove  146 ), the fitting can be rotated and locked at any desired position. 
     In a further embodiment, the lock down screws  142  have a section  150  of their shaft threaded. This threaded shaft section is spaced apart from the threaded head section of the screws which engage the threaded holes  126 . A lock nut  152  is threaded on the threaded section  150  formed on the shaft of each screw after the screws have locked the fitting on the bushing. The lock nut  152  has a central threaded bore section  154  which extends into a non-threaded bore section  156 . The non-threaded bore section has a diameter larger than the threaded bore section. As the nut is screwed on the threaded shaft, its unthreaded bore section contacts the fitting annular wall  128  outer surface. As it is further screwed, it exerts a radial outward force on the screw which is threaded on the fitting wall, thereby locking the screw in place. A retainer ring  158  may then be fitted on the screw behind the nut to prevent the nut from getting lost if it were to loosen. The screw with lock nut can be preassembled with the retainer ring in place. 
     In another embodiment an annular casing head  212  is coupled to the casing  214  using an annular coupling member  216  ( FIG. 4A ). Typically the casing head has a first annular portion  218  which tapers into a second annular portion  220  via a truncated cone shaped annular third portion  222 . The first portion has an inner diameter greater than the inner diameter of the second portion. The second portion has threads  224  formed on its outer surface at its and furthest from the first portion. The inner surface of the third portion defines a shoulder  226  that slopes upward in a radially outward direction. 
     The coupling member  216  is a cylindrical member having inner threads. Preferably two sets of threads are formed beginning on the inner surface of the coupling member, one set at either end. The first set of threads  228  are matched to the outer threads  224  formed on the second portion of the casing head ( FIG. 4B ). The second set of threads  230  are matched to the outer threads  232  on the casing. The coupling through its second set of threads is threaded on the outer threads of the casing. The casing head is then threaded onto the first set of the coupling threads. 
     An annular groove  234  is formed on the outer surface of the first portion of the casing head near the intersection of the first portion with the truncated cone shaped portion. The annular groove has an annular upper surface  236  and an annular base  238 . 
     A quick connector fitting  240  is then mated to the casing head. The quick connector fitting has a first section  242  which extends into a second section  244  forming an inner annular shoulder  246  at interface between the first and second section inner surfaces. In other words, the fitting first section has an inner diameter is larger than the inner diameter of the second section. The length of the first section as measured from the annular shoulder should be slightly less then the length  250  measured from the mouth of the casing head to the upper surface of the annular groove. A flange extends from the end of the second section opposite the first section providing an interface for connecting well related equipment. 
     Preferably two annular grooves  254  are formed on the inner surface of the first section, preferably on the upper thicker wall portion of the section. A flange seal  256 , which is typically an  0 -ring seal, is fitted into each groove. An annular wall  252  defines the fitting first section. The annular wall  252  is thinner at the open or lower end of the first section. However, the inner diameter of the first section in constant throughout the length of the section. Threads  260  are formed on the outer surface of the lower thinner portion  258  of the fitting first section. 
     An annular drilling flange nut  262  has an annular upper section  264 , an annular intermediate section  266  and an annular lower section  268  ( FIGS. 4A and 4C ). The inner surface diameter of the upper section is smaller than the inner surface diameter of the intermediate section and greater than the inner surface diameter of the lower section. The inner surface diameter of the lower section should preferably be at least slightly larger than the outer surface diameter of the casing head first section  218 . The three sections form an annular channel  272 . Threads  270  are formed on inner surface of the upper annular section matched to the threads  260  on the outer surface of the lower portion  258  of the fitting first section. 
     The outer surface of the drilling flange nut  242  preferably has an octagonal shape providing grip  274  areas for torquing on to the fitting using a wrench or a hammer ( FIG. 4D ). Radial openings  276  are formed equidistantly through the nut outer surface penetrating the nut intermediate section and exiting on the annular channel  272  formed on the inner surface of the flange nut. The openings are formed to accommodate load key bolts  278 . Each load key bolt is rotatably connected to a retainer  280 . The retainer is perpendicular to the load key bolt. Each load key bolt can rotate relative to, but cannot longitudinal translate through, its corresponding retainer. The load key bolts are fitted through the radial opening  276  on the flange nut and the retainer  280  is bolted on the outer surface of the flange nut using retainer bolts  282 . 
     A tip portion  286  of each load key bolt shaft extending radially beyond its corresponding radial opening  276  is threaded. Each load key bolt is able to freely rotate relative to its corresponding opening  276  formed on the flange nut. An arc shaped load key  288  is threaded to each threaded shaft portion  286 . In a preferred embodiment, eight load keys are used, one for each load key bolt. Each load key is an eighth of a ring section. The load key bolt is threaded to a threaded opening  290  formed on the center section of the load key causing the load keys to translate radially outward and rest against the annular channel  272  formed on the flange nut. 
     The inner surface diameter of the quick connector first section  242  is slightly greater than the outer surface diameter of the casing head first portion  218 . The quick connector is slid over the casing head until the annular shoulder  246  sits on the mouth  292  of the casing head ( FIG. 4E ). When at this position, the lowest end  243  of the fitting first section  242  extends almost to the upper surface  236  of the annular groove formed on the outer surface of the casing head. The fitting is rotated in relation to the casing head to a desired orientation. 
     The flange nut is then threaded to the outer threads  260  formed on the first section of the fitting. The flange nut may also be pre-threaded on the first section of the fitting prior to mounting the fitting over the casing head. When the flange nut is threaded on the fitting, the load keys are sandwiched between the lower portion  288  of the flange nut  262  and the lower end  243  of the fitting first section. 
     The flange nut is threaded sufficiently for aligning the load keys with the groove  234  formed on the outer surface of the casing head. Each load key bolt is then rotated causing its respective load key to unthread from the load key bolt and travel radially inward into the groove  234  formed on the casing head ( FIG. 4D ). The load keys bolts are rotated until the load keys stop against the base  238  of the casing head groove without exerting a force on the groove. When in that position, preferably, all the load keys abut each other forming a continuous ring. 
     The flange nut is then further torqued on the lower portion of the fitting first section causing the load keys to contact and apply a force against the upper surface  236  of the annular groove  234  on the casing head ( FIG. 4F ). As result, a downward force is applied by the flange nut on the quick connector first section causing the quick connector to further sit on the mouth  292  of the casing head forming a tight connection. 
     In an alternate embodiment, a casing head  312  is directly threaded on to the casing  314  ( FIGS. 5A and 5C ). With this embodiment, the casing head has a first portion  318 . A second portion  320  extends below from the first portion. Threads  394  are formed in the lower inner surface of the second portion. These threads are matched to threads  328  formed on the outer surface of the casing head allowing for the torquing of the casing head to the casing ( FIG. 5B ). An annular lip  396  is formed on the inner surface of the second portion. The annular lip formes an upper shoulder  395  that slopes upward in a radially outward portion direction. In addition, the annular lip forms a lower annular shoulder  326 . The quick connector fitting  340  mates with the casing head as described above in relation to the previous embodiment. The quick connector fitting also has a first section  342  which extends into a second section  344  forming an inner annular shoulder  346  at the interface between the first and second section inner surfaces. 
     With any of the above described embodiments, a wear bushing  400  ( FIGS. 4E and 5C ) may be fitted such that it lines the inner surface of the casing head first portion  218 ,  318  and a portion of the quick connector inner surface extending above the casing head first portion. When in position, typically, the bottom edge  401  of the wear bushing which is sloped mates with and rests against the sloping shoulder  226 ,  326  formed on inner surface of the casing head. Preferably, a threaded hole  298 ,  398  is formed radially through the second section  244 ,  324  of the quick connector fitting near the fitting inner shoulder  246 ,  346 . When the wear bushing is properly seated, the threaded hole provides access to an outer surface of the bushing. A lock screw  299 ,  399  is threaded through the threaded hole for engaging and locking the wear bushing in place. 
     With any of the aforementioned embodiments, the BOP  8  ( FIGS. 4A ,  4 E,  5 A,  5 C) or other well related equipment is connected, typically by fasteners, to the fitting. In this regard, the BOP or other well related equipment can be easily connected to or disconnected from the well casing. 
     Although the present invention has been described and illustrated to respect to multiple embodiments thereof, it is to be understood that it is not to be so limited, since changes and modifications may be made therein which are within the full intended scope of this invention as hereinafter claimed.