The present disclosure is directed to a tubing head assembly for housing a tubing hanger in a well completion system. More particularly, the disclosure is directed to a tubing head assembly which in a first configuration comprises a bore having a diameter approximately the same as or larger than the diameter of the wellhead bore to enable drilling of the well bore through the tubing head assembly prior to installation of the tubing hanger, and in a second configuration comprises a bore which is sufficiently small to engage with the tubing hanger.
Prior art vertical-type well completion systems typically include a wellhead positioned at the upper end of a well bore, a christmas tree positioned above the wellhead and a tubing hanger positioned in the wellhead. During completion of such systems, a blowout preventer (BOP) is connected to the top of the wellhead, the well bore is drilled through the BOP and the wellhead, and the tubing hanger is lowered through the BOP and landed in the wellhead, after which the BOP is removed and the christmas tree is installed on the wellhead.
In certain applications it is not desirable or possible to position the tubing hanger in the wellhead. In these instances, a tubing head (which is sometimes referred to as a tubing spool) is mounted to the top of the wellhead and the tubing hanger is positioned in the tubing spool. Traditional tubing heads normally include means located in the tubing head bore for orienting the tubing hanger to the tubing head, a landing shoulder on which the tubing hanger is supported, and a number of exposed sealing profiles for the tubing hanger, which are commonly located on or adjacent reduced diameter steps in the tubing head bore.
These features restrict the tubing head bore and normally make drilling of the well bore through the tubing head impractical. As a result, the well bore must typically be drilled through the BOP and the wellhead, the well must be secured, the BOP must be temporarily removed so that the tubing head can be installed, and then the BOP must be re-installed before the tubing hanger can be installed in the tubing head. These procedures are time consuming and costly.
In some well completion systems the well bore can be drilled through the tubing head. However, these systems require a reduced bore wellhead system, which can create limitations to drilling.
In accordance with the present disclosure, these and other disadvantages are addressed by providing a tubing head assembly for housing a tubing hanger in a well completion system. The well completion system includes a wellhead positioned at the upper end of a well bore and a christmas tree positioned above the wellhead, and the tubing head system comprises a tubing head connectable to the top of the wellhead, the tubing head comprising an axially extending central bore; and a tubular adapter sleeve configured to be secured and sealed in the central bore, the adapter sleeve including an axially extending sleeve bore which is configured to receive the tubing hanger. In use of the tubing head assembly, the tubing hanger is positioned in the sleeve bore and the adapter sleeve is positioned in the central bore to thereby position the tubing hanger in the tubing head.
In accordance with one embodiment, the adapter sleeve may comprise an annular tubing hanger landing shoulder, and in use of the tubing head assembly the tubing hanger is supported on the tubing hanger landing shoulder.
In accordance with another embodiment, the wellhead comprises a wellhead bore having a first nominal diameter and the central bore may have a second nominal diameter which is approximately the same as the first nominal diameter.
In accordance with yet another embodiment, the tubing head may comprise a first locking profile located in the central bore and the adapter sleeve may comprise a first locking element which is engageable with the first locking profile to thereby secure the adapter sleeve to the tubing head.
In accordance with a further embodiment, the tubing head may comprise an annular first sealing profile located in the central bore and the adapter sleeve may comprise a first sealing element which is configured to sealingly engage the first sealing profile to thereby seal an annulus between the central bore and the adapter sleeve. In one exemplary embodiment, the first sealing profile may be approximately flush with or recessed in the central bore. In another exemplary embodiment, the adapter sleeve may comprise an annular second sealing profile and the first sealing element may be configured to sealingly engage both the first and second sealing profiles to thereby seal the annulus between the central bore and the adapter sleeve.
In accordance with one embodiment, the adapter sleeve may comprise a second locking profile located in the sleeve bore which is operatively engageable by a second locking element on the tubing hanger to thereby secure the tubing hanger to the adapter sleeve, and the sleeve bore may comprise an annular third sealing profile configured to be sealingly engaged by a second sealing element on the tubing hanger to thereby seal an annulus between the tubing hanger and the adapter sleeve.
In accordance with another embodiment, the tubing head assembly may comprise means for orienting the adapter sleeve to the tubing head. The means for orienting the adapter sleeve to the tubing head may comprise, for example, a key supported on the adapter sleeve and a corresponding slot formed in the central bore. In this example, the slot is positioned so as to receive the key when the adapter sleeve is in a predetermined orientation relative to the tubing head. In one exemplary embodiment, the tubing head assembly may also comprise means for orienting the tubing hanger to the adapter sleeve.
In accordance with another embodiment, the adapter sleeve may comprise a first bypass bore which extends from a part of the sleeve bore below the third sealing profile to a part of the central bore below the first sealing profile. In a further embodiment, the tubing head may comprise a second bypass bore which extends from the part of central bore below the first sealing profile to a part of the central bore above the first sealing profile. Additionally, the tubing head may comprise a bypass valve and the second bypass bore may comprise a first branch which extends from the part of the central bore below the first sealing profile to the bypass valve and a second branch which extends from the bypass valve to the part of the central bore above the first sealing profile. In this example, the bypass valve is operable to open or close the first branch.
In accordance with yet another embodiment, the adapter sleeve may include a downward facing load shoulder which is configured to engage a load component located in the wellhead, and the adapter sleeve may be configured to transfer the weight of the tubing hanger from the tubing hanger landing shoulder through the load shoulder to the load component. In one exemplary embodiment, the adapter sleeve may comprise a load nut on which the load shoulder is located, and the load nut may be axially movable relative to the first locking element to thereby adjust an axial distance between the first locking element and the load shoulder.
In accordance with a further embodiment of the disclosure, the central bore may comprise an annular groove and the adapter sleeve may comprises a tubular body portion on which the tubing hanger landing shoulder is located, the body portion comprising a radially outwardly directed actuating surface and a downwardly directed load shoulder located above the actuating surface; a trigger sleeve positioned at least partially below the body portion, the trigger sleeve being slidably supported relative to the body portion; and a load ring radially moveably supported on the trigger sleeve, the load ring being configured to engage the actuation surface and the load shoulder. In this embodiment, the body portion is movable relative to the trigger sleeve from a first position in which the actuating surface is located above the load ring to a second position in which at least a part of the actuating surface is located radially adjacent the load ring. Further, the actuating surface may be configured such that, when the body portion is moved axially downwardly relative to the trigger sleeve from its first position to its second position, the actuating surface will force the load ring radially outwardly into engagement with the groove. In this example, in the second position of the body portion, the load shoulder engages the load ring such that the weight of the tubing hanger is transmitted from the tubing hanger landing shoulder through the load shoulder and the load ring to the tubing head.
In accordance with one aspect, the trigger sleeve may comprise a downwardly directed trigger shoulder configured to engage a trigger component located in the wellhead to thereby maintain the load ring in a fixed axial position relative to the tubing head. In accordance with another aspect, the adapter sleeve may comprise an energizing mandrel which is movable to force the first sealing element into engagement with the first sealing profile or with both the first and second sealing profiles, and wherein the first locking element is supported on the energizing mandrel. In certain embodiments, the energizing mandrel may comprise an upper mandrel part which is axially movably connected to a lower mandrel part. In this example, the first locking element may be supported on the upper mandrel part and the upper mandrel part may be axially movable relative to the lower mandrel part to thereby adjust an axial distance between the first locking profile and the load shoulder on the adapter sleeve.
In accordance with yet another embodiment, the second locking profile may be located on the energizing mandrel.
The present disclosure is also directed to a method of installing a tubing hanger in a well completion system comprising a wellhead positioned at an upper end of a well bore. In accordance with one embodiment, the method comprises the steps of providing a tubing head assembly which includes a tubing head having an axially extending central bore and a tubular adapter sleeve configured to be secured and sealed in the central bore, the adapter sleeve including an axially extending sleeve bore configured to receive the tubing hanger; mounting the tubing head to the wellhead; positioning the adapter sleeve in the central bore; securing and sealing the adapter sleeve to the tubing head; positioning the tubing hanger in the sleeve bore; and securing and sealing the tubing hanger to the adapter sleeve.
In accordance with a further embodiment, the method may comprise the step of orienting the adapter sleeve to the central bore.
In accordance with yet another embodiment, the sleeve bore may comprise an annular landing shoulder and the step of positioning the tubing hanger in the sleeve bore may comprise positioning the tubing hanger on the landing shoulder. In accordance with an exemplary embodiment, the step of positioning the adapter sleeve in the central bore may comprise supporting the adapter sleeve on a load component located in the wellhead. In this example, the weight of the tubing hanger is transmitted through the adapter sleeve and the load component to the wellhead.
In accordance with another exemplary embodiment, the step of positioning the adapter sleeve in the central bore may comprise supporting the adapter sleeve on a load ring which is engaged in an annular groove located in the central bore. In this example, the weight of the tubing hanger is transmitted through the adapter sleeve and the load ring to the tubing head.
In accordance with one embodiment, the method further comprises the step of, prior to the step of supporting the adapter sleeve on the load ring, forcing the load ring into engagement with the groove. In this example, the step of forcing the load ring into engagement with the groove is performed by the adapter sleeve during the step of positioning the adapter sleeve in the central bore. In accordance with one aspect, the adapter sleeve may comprise a tubular body portion and a trigger sleeve which is positioned at least partially below the body portion, the load ring may be supported on the trigger sleeve, and the step of forcing the load ring into engagement with the groove may be performed by the body portion by moving the body portion axially toward the trigger sleeve.
In accordance with yet another embodiment, the method may comprise the step of, prior to the step of positioning the adapter sleeve in the central bore, drilling the well bore through the tubing head and the wellhead.
The present disclosure is also directed to a tubing head assembly for housing a tubing hanger in a well completion system comprising a wellhead positioned at the upper end of a well bore and a christmas tree positioned above the wellhead. In accordance with one embodiment, the tubing head system comprises a tubing head connectable to the top of the wellhead, the tubing head comprising an axially extending central bore, an annular locking profile formed in the central bore, and an annular sealing profile located in the central bore. The locking profile may be engageable by a locking element on the tubing hanger to thereby lock the tubing hanger to the tubing head, and the sealing profile may be sealingly engageable by a sealing element on the tubing hanger to thereby seal an annulus between the central bore and the tubing hanger. In use of the tubing head assembly, the tubing hanger is positioned in the central bore to thereby position the tubing hanger in the tubing head.
In accordance with one embodiment of the disclosure, the sealing profile may be approximately flush with the central bore. In one aspect, the sealing profile may be recessed in the central bore.
In accordance with a further embodiment, the wellhead comprises a wellhead bore having a first nominal diameter and the central bore has a second nominal diameter which may be approximately the same as the first nominal diameter.
In accordance with yet another embodiment, the tubing head assembly may include means for orienting the tubing hanger to the tubing head.
In accordance with another embodiment, the tubing hanger may be supported on a load component located in the wellhead.
In accordance with yet another embodiment, the tubing head may comprise a bypass bore which extends from a part of central bore below the sealing profile to a part of the central bore above the sealing profile. In one aspect, the tubing head may also comprise a bypass valve and the bypass bore may comprise a first branch which extends from the part of the central bore below the first sealing profile to the bypass valve and a second branch which extends from the bypass valve to the part of the central bore above the sealing profile. In this example, the bypass valve is operable to open or close the first branch.
In accordance with another embodiment of the disclosure, the central bore comprises an annular groove and the tubing hanger comprises a tubular body portion having a radially outwardly directed actuating surface and a downwardly directed load shoulder located above the actuating surface; a trigger sleeve slidably supported relative to the body portion; and a load ring radially moveably supported on the trigger sleeve, the load ring being configured to engage the actuation surface and the load shoulder. In this embodiment, the body portion is movable relative to the trigger sleeve from a first position in which the actuating surface is located above the load ring to a second position in which at least a part of the actuating surface is located radially adjacent the load ring. The actuating surface may be configured such that, when the body portion is moved axially downwardly relative to the trigger sleeve from its first position to its second position, the actuating surface will force the load ring radially outwardly into engagement with the groove. Also, in the second position of the body portion, the load shoulder engages the load ring such that the weight of the tubing hanger is transmitted through the load shoulder and the load ring to the tubing head. In accordance with one aspect, the trigger sleeve may comprise a downwardly directed trigger shoulder configured to engage a trigger component located in the wellhead to thereby maintain the load ring in a fixed axial position relative to the tubing head.
Thus, the tubing head assembly of the present disclosure enables drilling and completion of the well bore through the tubing head without any of the limitations discussed above. In certain embodiments this is accomplished by designing the tubing head such that the central bore does not include any features which could limit full bore access to the wellhead bore, such as load shoulders, trigger shoulders or exposed seal bores. To the contrary, in some embodiments the first sealing profile is approximately flush with or recessed in the central bore. In addition, the first locking profile and the orientation slot are recessed in the central bore. Moreover, in certain embodiments the nominal diameter of the central bore is approximately the same as that of the wellhead bore. As a result, the tubing head is capable of providing full bore access to the wellhead bore, which will enable drilling and completion of the well bore through the tubing head.
These and other objects and advantages of the present disclosure will be made apparent from the following detailed description, with reference to the accompanying drawings. In the drawings, the same reference numbers may be used to denote similar components in the various embodiments.
The present disclosure is directed to a tubing head assembly for a well completion system. The tubing head assembly is particularly suitable for use in vertical-style well completion systems, which typically include a wellhead which is positioned at the upper end of a well bore, a christmas tree which is mounted to the top of the wellhead and a tubing hanger which is landed in the wellhead. The tubing head assembly is especially suitable for use in certain well completion systems in which it is not desirable or possible to position the tubing hanger in the wellhead. In these and other applications, the tubing head assembly provides a means for housing the tubing hanger above the wellhead and below the christmas tree. In certain configurations, the tubing head assembly provides full-bore access to the wellhead, which enables drilling and completion of the well bore through the tubing hanger assembly.
In accordance with one embodiment of the disclosure, the tubing head assembly includes a tubing head having an axially extending central bore and a tubular adapter sleeve configured to be secured and sealed in the central bore. The adapter sleeve includes an axially extending sleeve bore which is configured to receive the tubing hanger. In use of the tubing head assembly, the tubing head is connected to the top of the wellhead, the tubing hanger is secured and sealed to adapter sleeve, and the adapter sleeve is secured and sealed to the central bore. This embodiment of the tubing head assembly eliminates the need for the central bore to include a tubing hanger landing shoulder or other features which could otherwise restrict the size of the central bore and inhibit the ability to drill and complete the well through the tubing head.
A first embodiment of the tubing head assembly of the present disclosure is shown in
Referring to
In an alternative embodiment (not shown), the adapter sleeve 24 may be configured such that the tubing hanger 30 extends through the sleeve bore 26 and is supported on a load component located in the wellhead 12, such as the casing hanger 16, an intermediate casing hanger (not shown), or the landing shoulder 18.
As shown in
As an example, in this embodiment the tubing head 20 can be installed with or shortly after the wellhead 12 is installed, a BOP can be installed on the tubing head, and the well bore can be drilled through the tubing head and the wellhead, after which the adapter sleeve 24 and the tubing hanger 30 can be installed in the tubing head without having to remove and retrieve the BOP. By comparison, in typical prior art well completion systems requiring the use of a tubing head, the BOP is lowered from the surface vessel and installed on the wellhead, the well bore is drilled through the wellhead, the well is suspended (i.e., made secure by installing one or more temporary barriers in the well bore), the BOP is removed from the wellhead, the tubing head is lowered from the surface vessel and installed on the wellhead, the BOP is installed on the tubing head, the temporary barriers are removed, and then the tubing hanger is installed in the tubing head. Thus, the tubing head system 10 of the present embodiment eliminates the need for several time consuming running and retrieval operations.
The tubing head assembly 10 may be mounted to the wellhead 12 using any suitable means. For example, a conventional hydraulic connector 32 may be attached to the lower end of the tubing head 20 and then connected to the top of the wellhead 12 in a known manner to thereby secure the tubing head to the wellhead. Also, the tubing head 20 may be sealed to the wellhead 12 using a conventional sealing element, such as a VX gasket 34.
In certain embodiments of the disclosure, the tubing head assembly 10 may also include means for sealing the adapter sleeve 24 to the tubing head 20. Referring still to
The first sealing element 38 may comprise any appropriate seal which is suitable for sealing the annulus between the central bore 22 and the adapter sleeve 24 against anticipated pressures in the well bore. In the embodiment shown in
In the illustrative embodiment of the disclosure shown in
The first sealing element 38 and the first and second sealing profiles 36, may in some embodiments be made of suitable metal materials in order to provide a metal-to-metal seal between the central bore 22 and the adapter sleeve 24. Metal-to-metal seals are generally better able to withstanding the high pressures and temperatures typically encountered in certain subsea flow completion applications than non-metal seals.
In accordance with some embodiments, the tubing head system 10 may include means for forcing the first sealing element 38 into engagement with the first and second sealing profiles 36, 40 (or with just the first sealing profile in embodiments such as described above in which the first sealing element is connected to or formed integrally with the adapter sleeve 24). As shown in
In certain embodiments the tubing head assembly 10 may also include means for securing the adapter sleeve 24 to the tubing head 20. Referring still to
Referring also to
In the example shown in
Referring still to
In particular flow completion systems in which the tubing hanger 30 is required to be oriented to the tubing head 20, the tubing head assembly 10 may include means for orienting the adapter sleeve 24 to the tubing head 20 and/or means for orienting the tubing hanger 30 to the adapter sleeve. As shown in
In some embodiments, the key 64 may be retractable, in which event the means for orienting the adapter sleeve 24 to the tubing head 20 may also include a biasing element 68, such as a spring, for biasing the key radially outwardly. In this manner, after the adapter sleeve 24 is positioned in the central bore 22, the adapter sleeve may be rotated relative to the tubing head 20 until the key 64 enters the slot 66, at which point the adapter sleeve will be properly oriented relative to the tubing head. As shown in
In an alternative embodiment, the key 64 may be supported on the tubing head 20 and the slot 66 may be located on the adapter sleeve 24. In another alternative embodiment, the means for orienting the adapter sleeve 24 to the tubing head 20 may include an orientation helix formed in the central bore 22 and a corresponding guide pin located on the adapter sleeve 24. Alternatively, the orientation helix may be formed on the adapter sleeve 24 and the guide pin may be located in the central bore 22.
The tubing head assembly 10 may in certain embodiments also comprise means for orienting the tubing hanger 30 to the adapter sleeve 24. Such means may comprise, for example, an orientation helix 70 which is located on the adapter sleeve 24 and is configured to be engaged by a guide pin (not shown) on the tubing hanger 30. In some embodiments the orientation helix 70 may be formed or otherwise located in the sleeve bore 26. In combination with the means described above for orienting the adapter sleeve 24 to the tubing head 20, the means for orienting the tubing hanger 30 to the adapter sleeve will thus ensure that the tubing hanger is properly oriented to the tubing head.
In an alternative embodiment which is not shown in the drawings, the means for orienting the tubing hanger 30 to the adapter sleeve 24 may comprise an orientation helix formed on or connected to the tubing hanger and a guide pin located on the adapter sleeve, such as in the sleeve bore 26. In yet another alternative embodiment, the means for orienting the tubing hanger 30 to the adapter sleeve 24 may include a key and slot arrangement of the type described above. In this embodiment, a key similar to the key 64 may be located on one of the adapter sleeve 24 and the tubing hanger 30 and a slot similar to the slot 66 may be located on the other of the adapter sleeve and the tubing hanger.
In the specific embodiment of the tubing head assembly 10 shown in
In certain flow completion systems in which access to the tubing annulus is required or desired, the adapter sleeve 24 may be provided with a first bypass bore 76 that extends laterally from the sleeve bore 26 to a radially outer portion of the adapter sleeve which, when the adapter sleeve is installed in the tubing head 20, communicates with the annulus between the adapter sleeve and the tubing head. For example, the first bypass bore 76 may extend from a part of the sleeve bore 26 located below the third sealing profile 50 to a radially outer portion of the adapter sleeve 24 located below the first sealing profile 36. In this manner, when the tubing hanger 30 is positioned in the adapter sleeve and the adapter sleeve is positioned in the tubing head 20, the first bypass bore 76 will extend between a part of the sleeve bore 26 located below the second sealing element 52 and a part of the central bore 22 located below the first sealing element 38.
In addition, the tubing head assembly 10 may be configured such that the first bypass bore 76 communicates with a second bypass bore 78 that extends through the tubing head 20 from the central bore 22. In certain embodiments, the second bypass bore 78 may communicate with a part of the central bore 22 located above the first sealing element 38. In some embodiments the second bypass bore 78 may extend to an outer diameter surface of the tubing head 20. In particular embodiments the tubing head 20 may comprise a bypass valve 80 for controlling flow through the second bypass bore 78. In this embodiment, the second bypass bore 78 extends to the bypass valve 80, which may be mounted, e.g., on the outer diameter surface of the tubing head 20 (as shown in
Referring still to
In certain embodiments, the adapter sleeve 24 may include a cylindrical load nut 96 which is axially movably supported on the body 88. For example, the load nut 96 may be threadedly connected to the body 88 such that rotation of the load nut relative to the body will result in axial movement of the load nut relative to the body. In this example, the load shoulder 72 may be formed on the load nut 96. In this manner, the load nut 96 may be rotated relative to the body 88 to adjust the axial space-out of the adapter sleeve 24 relative to the tubing head 20 (i.e., the axial distance between the load shoulder 72 on the adapter sleeve and the locking profile 44 on the tubing head 20).
In the specific embodiment of the tubing head assembly 10 shown in
The present disclosure is also directed to a method of installing the tubing head assembly 10, one embodiment of which will be described with reference to
Referring to
Referring to
In the present embodiment the tubing hanger 30 is installed in the adapter sleeve 24 after the adapter sleeve is installed in the tubing head 20. During this step, the tubing hanger 30 is connected to a suitable installation tool (not shown) and lowered through the BOP 98 and into the sleeve bore 26. Referring to
In an alternative embodiment, the tubing hanger 30 may be connected to the adapter sleeve 24 prior to the adapter sleeve being installed in the tubing head 20. In this embodiment, the tubing hanger 30 is connected to a suitable installation tool, lowered into the sleeve bore 26 until it lands on the landing shoulder 28, and then locked to the adapter sleeve 24 by actuating the second locking mandrel 62 to force the second locking element 60 radially outwardly into the second locking profile 58. These steps may be performed on a surface vessel.
In this alternative embodiment, the tubing hanger 30 with the adapter sleeve 24 connected thereto is then lowered through the BOP 98 into the central bore 22 until the until the load shoulder 72 on the adapter sleeve engages the landing seat 74 on the casing hanger 16 (or other load component located in the wellhead 12, as discussed above). At this point, the adapter sleeve 24 may be rotated (by means of a landing string connected to the installation tool, for instance) until the key 64 enters the slot 66 to thereby ensure that the adapter sleeve is in its proper orientation relative to the tubing head 20. The energizing mandrel 42 may then be actuated to force the sealing element 38 into sealing engagement with the first and second sealing profiles 36, 40 (or with just the first sealing profile 36 if the sealing element 38 is so configured), after which the first locking mandrel 48 is actuated to force the first locking element 46 radially outwardly into operative engagement with the first locking profile 44 to thereby secure the adapter sleeve 24, and thus the tubing hanger 30, to the tubing head 20.
In order to retrieve the tubing hanger 30 from the tubing head 20, a suitable retrieval tool (not shown) may be connected to the tubing hanger, the energizing mandrel 42 and the first locking mandrel 48. If the first locking mandrel 48 is slidably connected to the energizing mandrel 42 (e.g., using the hook means described below in connection with the embodiment of
The tubing hanger 30 and the adapter sleeve 24 may also be retrieved independently. In this example, a suitable retrieval tool (not shown) is connected to the tubing hanger 30 and the second locking mandrel 62 is lifted to thereby unlock the tubing hanger from the adapter sleeve 24, after which the tubing hanger may be retrieved to the surface. Then, a suitable retrieval tool (not shown) is secured to the energizing mandrel 42 and the first locking mandrel 48. If the first locking mandrel 48 is slidably connected to the energizing mandrel 42 (e.g., using the hook means described below in connection with the embodiment of
In the embodiments described above, the tubing head assembly 10 is configured to support the tubing hanger 30 in the wellhead 12. However, in certain flow completion systems, size constraints or other limitations may make it impractical or undesirable to support the tubing hanger 30 in the wellhead 12. In accordance with further embodiments of the disclosure, therefore, a tubing head assembly is provided which is configured to support the tubing hanger directly in the tubing head 20. In this embodiment, the weight of the tubing hanger and its associated tubing string is transmitted through the adapter sleeve to the tubing head and then from the tubing head to the wellhead.
An illustrative embodiment of such a tubing head assembly is shown in
In the present embodiment, the tubing head assembly 100 comprises a tubing head 20 and an adapter sleeve 24 which is configured to be secured and sealed in the tubing head. The tubing head 20 may be similar in most respects to the tubing head 20 described above. Accordingly, the tubing head 20 may include a central bore 22, an annular first sealing profile 36 located in the central bore, and an annular first locking profile 44 located in the central bore. The tubing head 20 may also include means for orienting the adapter sleeve 24 to the tubing head, such as a slot 66 configured to be engaged by a key 64 supported on the adapter sleeve 24, as described above. Also, the tubing head 20 may be secured to the wellhead 12 by any suitable arrangement, such as by means of a conventional hydraulic connector 32. In the present embodiment of the tubing head assembly 100, the tubing head 20 additionally includes an annular groove 102 formed or otherwise located in the central bore 22, the purpose of which will be made apparent below.
The adapter sleeve 24 of the present embodiment may include many of the features of the adapter sleeve 24 described above. Accordingly, the adapter sleeve 24 may include an axially extending sleeve bore 26 which is configured to receive the tubing hanger 30. The adapter sleeve 24 may also include an annular landing shoulder 28 on which the tubing hanger 30 is supported. The landing shoulder 28 may be located, e.g., in the sleeve bore 26. In other embodiments, the adapter sleeve 24 may be configured such that the tubing hanger 30 extends through the sleeve bore 26 and is supported on a load component located in the wellhead 12.
In certain embodiments the adapter sleeve 24 may also include an annular first sealing element 38 configured to sealingly engage the first sealing profile 36 to thereby seal the annulus between the tubing head 20 and the adapter sleeve against pressure in the well bore. Depending on the configuration of the first sealing element 38, the adapter sleeve 24 may also comprise an annular second sealing profile 40 configured for sealing engagement by the first sealing element.
In some embodiments the adapter sleeve 24 may additionally include one or more of an energizing mandrel 42 for forcing the first sealing element 38 into sealing engagement with the first sealing profile 36 (or with both the first and second sealing profiles 36, 40 if the first sealing element is so configured), a first locking element 46 configured to engage the first locking profile 44 to thereby secure the adapter sleeve to the tubing head 20, a first locking mandrel 48 for forcing the first locking element into operative engagement with the first locking profile, and an annular third sealing profile 50 for sealing engagement by an annular second sealing element 52 on the tubing hanger 30 (see
As in the previous embodiment, the adapter sleeve 24 may also include a second locking profile 58 configured to be engaged by a second locking element 60 supported on the tubing hanger 30 to thereby secure the tubing hanger to the adapter sleeve. In this regard, the tubing hanger 30 may include a second locking mandrel 62 for forcing the second locking element 60 into engagement with the second locking profile 58 (see
Referring still to
The body portion 104 is slidably supported relative to the trigger sleeve 106 and, in certain aspects, may function as an actuating mandrel for the load ring 108. As seen best in
In this embodiment the body portion 104 may also include a downwardly directed load shoulder 114 which is configured to engage the load ring 108 when the body portion is in its second position and the load ring is engaged with the groove 102. The load shoulder 114 may be located above the actuating surface 112, such as at an upper end of the actuating surface. In this manner, when the body portion 104 is in its second position and the load ring 108 is engaged with the groove 102, the weight of the tubing hanger 30 will be transmitted through the load shoulder 114 and the load ring 108 to the tubing head 20.
In some embodiments the energizing mandrel 42 may include an upper mandrel part 42a which is axially movably connected to a lower mandrel part 42b. For example, the upper mandrel part 42a may be threadedly connected to the lower mandrel part 42b such that rotation of the upper mandrel part relative to the lower mandrel part will result in axial movement of the upper mandrel part relative to the lower mandrel part. In this manner, the upper mandrel part 42a may be rotated relative to the lower mandrel part 42b to adjust the axial space-out of the adapter sleeve 24 relative to the tubing head 20 (i.e., the axial distance between the load shoulder 114 on the adapter sleeve and the first locking profile 44 on the tubing head 20).
Referring still to
One exemplary method of installing the tubing head assembly 100 will be described with reference to
As shown in
Referring to
Referring to
In the present embodiment the tubing hanger 30 is installed in the adapter sleeve 24 after the adapter sleeve is installed in the tubing head 20. During this step, the tubing hanger 30 is connected to a suitable installation tool (not shown) and lowered through the BOP 98 and into the sleeve bore 26. Referring to
In an alternative embodiment, the tubing hanger 30 may be assembled with the adapter sleeve 24 prior to being lowered into the tubing head 20. During this step, the tubing hanger 30 is connected to a suitable installation tool and lowered into the sleeve bore 26 until the second locking element 60 is positioned opposite the second locking profile 58, after which the second locking mandrel 62 is actuated to lock the tubing hanger to the adapter sleeve 24. In subsea applications, this step may be performed on the surface vessel. Then, the tubing hanger 30, with the adapter sleeve 24 connected thereto, is lowered through the BOP 98 and into the tubing head 20. During this step, the body portion 104 is in its first or upper position relative to the trigger sleeve 106. The body portion 104 may be held in this position by use of any suitable means, such as a number of shear pins.
In this alternative embodiment, the tubing hanger 30 is lowered into the tubing head 20 until the trigger shoulder 116 on the trigger sleeve 106 engages the trigger component located in the wellhead 12, such as the landing seat 74 on the casing hanger 16. Once the trigger shoulder 116 engages the trigger component, further downward movement of the trigger sleeve 106 is prevented. In this position, the load ring 108 is located opposite the groove 102. Continued downward movement of the tubing hanger 30 through the tubing head 20 will cause the body portion 104 to move axially downwardly relative to the trigger sleeve 106 from its first or raised position to its second or lowered position. During this movement, the actuating surface 112 on the body portion 104 will force the load ring 108 radially outwardly into the groove 102. Also, in embodiments in which the tubing head assembly 100 includes means for orienting the adapter sleeve 24 relative to the tubing head 20 and such means comprises a key 64 and slot 66 arrangement, the adapter sleeve 24 may be rotated until the key enters the slot to thereby ensure that the adapter sleeve 24 is in its proper orientation relative to the tubing head.
The energizing mandrel 42 may then be actuated to force the sealing element 38 into sealing engagement with the first sealing profile 36 (or with the first and second sealing profiles 36, 40 if the sealing element is so configured), after which the first locking mandrel 48 may be actuated to force the first locking element 46 radially outwardly into operative engagement with the first locking profile 44 to thereby secure the adapter sleeve 24, and thus the tubing hanger 30, to the tubing head 20. After the tubing hanger 30 and the adapter sleeve 24 are fully installed in the tubing head 20 and any required seal tests and other procedures are performed, the BOP 98 may be removed and replaced with a christmas tree (not shown).
Referring still to
In accordance with another embodiment, the tubing hanger 30 and the adapter sleeve 24 may be retrieved independently. In this example, a suitable retrieval tool (not shown) is connected to the tubing hanger 30 and the second locking mandrel 62 is lifted to thereby unlock the tubing hanger from the adapter sleeve 24, after which the tubing hanger may be retrieved to the surface. Then, a suitable retrieval tool (not shown) is secured to the first locking mandrel 48 and the first locking mandrel is lifted to unlock the adapter sleeve 24 from the central bore 22. Continued upward movement of the first locking mandrel 48 will bring a fifth hook 126 on the first locking mandrel into engagement with a sixth hook 128 on the energizing mandrel 42. At this point, continued upward movement of the first locking mandrel 48 will pull the energizing mandrel 42 upward until the fourth hook 124 on the energizing mandrel engages the third hook 122 on the body portion 104. Continued upward movement of the first locking mandrel 48 will then pull the body portion 104 upward until the load ring 108 is released from the groove 102 and the second hook 120 engages the first hook 118. At this point, the adapter sleeve 24 is free of the central bore 22 and may be retrieved to the surface.
Another embodiment of a tubing head assembly according to the present disclosure is shown in
As shown in
The tubing head 202 is configured to be secured and sealed to a wellhead 12 by any suitable means, such as a conventional hydraulic connector 32 and a gasket 34. In this embodiment, the tubing hanger 30 is supported on a casing hanger 16 located in the wellhead 12. The casing hanger 16 may be supported, e.g., on a landing shoulder 18 (shown in phantom) formed on or secured to the wellhead bore 14, or on one or more intermediate casing hangers (not shown) which in turn are supported on the landing shoulder. As an alternative, the tubing hanger 30 may be supported directly on the landing shoulder 18.
In this embodiment, the tubing hanger 30 may include a sealing element 206 which is configured to sealingly engage the first sealing profile 36 to thereby seal the annulus between the tubing head 202 and the tubing hanger against pressure in the well bore. The tubing hanger 30 may also comprise one or more of an annular second sealing profile 208 which is configured to be sealingly engaged by the sealing element 206, an energizing mandrel 210 for energizing the sealing element 206 against the first sealing profile 36 (or against the first and second sealing profiles 36, 208, depending on the configuration of the sealing element), a locking element 212 which is configured to engage the locking profile 44 to thereby secure the tubing hanger to the tubing head 202, and a locking mandrel 214 for moving the locking element into engagement with the locking profile. These components may be similar in construction and operation to the like components described above.
As may be seen from
A further embodiment of a tubing head assembly according to the present disclosure is shown in
Referring to
In the present embodiment, the tubing hanger 30 is designed to be supported on a load ring 108 which is configured to be received in an annular groove 102 formed in the central bore 22. In particular, the tubing hanger 30 includes a tubular body portion 304 and a trigger sleeve 306 which is slidably supported on an outer diameter surface of the body portion. The trigger sleeve 306 is similar to the trigger sleeve 106 described above: it includes an upwardly facing trigger shoulder 110 on which the load ring 108 is radially movably supported and a downwardly directed triggered shoulder 116 which is configured to engage a trigger component located in the wellhead 12, such as, e.g., the landing seat 74 on the casing hanger 16.
As in the tubing head assembly 100 described above, the body portion 304 functions as an actuating mandrel for the load ring 108. Accordingly, the body portion 304 comprises a radially outwardly directed actuating surface 112 which in a first or raised position of the body portion is located above the load ring 108 and in a second or lowered position of the body portion (shown in
In this embodiment the body portion 304 also includes a downwardly directed load shoulder 114 which is configured to engage the load ring 108 when the body portion is in its second position and the load ring is engaged with the groove 102. The load shoulder 114 may be located above the actuating surface 112, such as at an upper end of the actuating surface. In this manner, when the body portion 304 is in its second position and the load ring 108 is engaged with the groove 102, the weight of the tubing hanger 30 will be transmitted through the load shoulder 114 and the load ring 108 to the tubing head 20.
Similar to the tubing hanger in the embodiment of the tubing head assembly 200 shown in
The tubing hanger 30 of this embodiment may be installed in the tubing head 302 by first connecting the tubing hanger to a suitable installation tool (not shown) and then lowering the tubing hanger into the tubing head until the trigger shoulder 116 on the trigger sleeve 306 engages the trigger component located in the wellhead 12, such as the landing seat 74 on the casing hanger 16. In this position, the load ring 108 is located opposite the groove 102. Continued downward movement of the tubing hanger 30 through the tubing head 302 will cause the body portion 304 to move axially downwardly relative to the trigger sleeve 106 from its first or raised position to its second or lowered position. During this movement, the actuating surface 112 on the body portion 104 will force the load ring 108 radially outwardly into the groove 102.
The energizing mandrel 210 may then be actuated to force the sealing element 206 into sealing engagement with the first sealing profile 36 (or with the first and second sealing profiles 36, 208 if the sealing element is so configured), after which the first locking mandrel 214 is actuated to force the first locking element 212 radially outwardly into operative engagement with the first locking profile 44 to thereby secure the tubing hanger 30 to the tubing head 302. After the tubing hanger 30 is fully installed in the tubing head 302 and any required seal tests and other procedures are performed, the BOP 98 may be removed and replaced with a christmas tree (not shown).
As may be seen from
It should be recognized that, while the present disclosure has been presented with reference to certain illustrative embodiments, those skilled in the art may develop a wide variation of structural and operational details without departing from the principles of the disclosure. For example, the various elements shown in the illustrative embodiments described above may be combined in a manner not specifically illustrated. Therefore, the following claims are to be construed to cover all equivalents falling within the true scope and spirit of the disclosure.