Rotating control device system with rams

A rotating control device (RCD) system includes a housing having a bore, a first ram assembly supported in the housing, and a second ram assembly supported within the housing. The first ram assembly includes a first ram and a first packer coupled to the first ram, and the second ram assembly includes a second ram and a second packer coupled to the second ram. The RCD system also includes a bearing assembly configured to enable the first packer and the second packer to rotate relative to the first ram and the second ram.

BACKGROUND

Natural resources have a profound effect on modern economies and societies. In order to meet the demand for such natural resources, numerous companies invest significant amounts of time and money in searching for, accessing, and extracting oil, natural gas, and other natural resources. Particularly, once a desired natural resource is discovered below the surface of the earth, drilling systems are often employed to access the desired natural resource. These drilling systems can be located onshore or offshore depending on the location of the desired natural resource. Such drilling systems may include a drilling fluid system configured to circulate drilling fluid into and out of a wellbore to facilitate drilling the wellbore.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

When introducing elements of various embodiments, the articles “a,” “an,” “the,” “said,” and the like, are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” “having,” and the like are intended to be inclusive and mean that there may be additional elements other than the listed elements. The use of “top,” “bottom,” “above,” “below,” and variations of these terms is made for convenience, but does not require any particular orientation of the components relative to some fixed reference, such as the direction of gravity. The term “fluid” encompasses liquids, gases, vapors, and combinations thereof. Numerical terms, such as “first,” “second,” and “third” may be used to distinguish components to facilitate discussion, and it should be noted that the numerical terms may be used differently or assigned to different elements in the claims. The drawing figures are not necessarily to scale. Certain features and components herein may be shown exaggerated in scale and/or in somewhat schematic form. Some details may not be shown in the interest of clarity and conciseness.

As set forth above, a drilling system may include a drilling fluid system that is configured to circulate drilling fluid into and out of a wellbore to facilitate drilling the wellbore. For example, the drilling fluid system may provide a flow of the drilling fluid through a drill string as the drill string rotates a drill bit that is positioned at a distal end portion of the drill string. The drilling fluid may exit through one or more openings at the distal end portion of the drill string and may return toward a platform of the drilling system via an annular space between the drill string and a casing that lines the wellbore.

In some cases, the drilling system may use managed pressure drilling (“MPD”). MPD regulates a pressure and a flow of the drilling fluid within the drill string so that the flow of the drilling fluid does not over pressurize a well (e.g., expand the well) and/or blocks the well from collapsing under its own weight. The ability to manage the pressure and the flow of the drilling fluid enables use of the drilling system to drill in various locations, such as locations with relatively softer sea beds.

The drilling system of the present disclosure may include a rotating control device (RCD) system. The RCD system may include a housing that defines a bore, and the drill string may extend through the bore during drilling operations. The RCD system may also include a seal element that is configured to seal against the drill string to thereby block a fluid flow (e.g., the drilling fluid, cuttings, and/or natural resources [e.g., carbon dioxide, hydrogen sulfide]) from passing across the seal element of the RCD system from the well toward the platform. The seal element may be coupled to rams (e.g., opposed rams) that are configured to move the seal element into and out of the bore to adjust the RCD system between an open configuration in which the seal element does not seal against the drill string and a closed configuration in which the seal element seals against the drill string. While the seal element is in the closed configuration, the fluid flow may be diverted toward another suitable location (e.g., a collection tank) other than the platform.

With the foregoing in mind,FIG. 1is a schematic diagram that illustrates an embodiment of a drilling system10that is configured to carry out drilling operations. The drilling system10may be a subsea system, although the disclosed embodiments may be used in a land-based (e.g., surface) system. The drilling system10may use MPD techniques. As illustrated, the drilling system10includes a wellhead assembly12coupled to a mineral deposit14via a well16having a wellbore18.

The wellhead assembly12may include or be coupled to multiple components that control and regulate activities and conditions associated with the well16. For example, the wellhead assembly12generally includes or is coupled to pipes, bodies, valves, and seals that enable drilling of the well16, route produced minerals from the mineral deposit14, provide for regulating pressure in the well16, and provide for the injection of drilling fluids into the wellbore18. A conductor22may provide structure for the wellbore18and may block collapse of the sides of the well16into the wellbore18. A casing24may be disposed within the conductor22. The casing24may provide structure for the wellbore18and may facilitate control of fluid and pressure during drilling of the well16. The wellhead assembly12may include a tubing spool, a casing spool, and a hanger to enable installation of the casing24. As shown, the wellhead assembly12may include or may be coupled to a blowout preventer (BOP) assembly25(e.g., BOP stack), which may include one or more ram BOPs26. For example, the BOP assembly25shown inFIG. 1includes at least one ram BOP26having moveable rams28(e.g., shear rams; pipe rams) configured to seal the wellbore18.

A drilling riser30may extend between the BOP assembly25and a platform32. The platform32may include various components that facilitate operation of the drilling system10, such as pumps, tanks, and power equipment. The platform32may also include a derrick34that supports a tubular36(e.g., drill string), which may extend through the drilling riser30. A drilling fluid system38may direct the drilling fluid into the tubular36, and the drilling fluid may exit through one or more openings at a distal end portion40of the tubular36and may return (along with cuttings and/or other substances from the well16) toward the platform32via an annular space (e.g., between the tubular36and the casing24that lines the wellbore18; between the tubular36and the drilling riser30). A drill bit42may be positioned at the distal end portion40of the tubular36. The tubular36may rotate within the drilling riser30to rotate the drill bit42, thereby enabling the drill bit42to drill and form the well16.

As shown, the drilling system10may include a rotating control device (RCD) system44that is configured to form a seal across and/or to block fluid flow through the annular space that surrounds the tubular36. For example, the RCD system44may be configured to block the drilling fluid, cuttings, and/or other substances from the well16from passing across a seal element of the RCD system44toward the platform32. The RCD system44may include moveable ram assemblies46that operate to move the seal element relative to the tubular36. The RCD system44may be positioned at any suitable location within the drilling system10, such as any suitable location between the wellbore18and the platform32. For example, as shown, the RCD system44may positioned between the BOP assembly25and the platform32. In some embodiments, the RCD system44may be included within the BOP assembly25(e.g., one or more ram BOPs26and components of the RCD system44may be within a housing of the BOP assembly25; one or more ram BOPs26and the RCD system44may be stacked vertically within the housing of the BOP assembly25).

In operation, the tubular36may be rotated about and/or moved along a vertical axis2to enable the drill bit42to drill the well16. As discussed in more detail below, the RCD system44may be controlled to provide a seal against the tubular36even as the tubular36moves within the drilling riser30. The drilling system10and its components may be described with reference to the vertical axis2(or vertical direction), a longitudinal axis4(or longitudinal direction), and a circumferential axis6(or direction) to facilitate discussion.

FIG. 2is a cross-sectional top view of the RCD system44. As shown, the RCD system44includes a first ram assembly50having a first packer52(e.g., seal element portion; elastomer seal) coupled to a first ram54(e.g., ram body; metal body) and a second ram assembly56having a second packer58(e.g., seal element portion; elastomer seal) coupled to a second ram60(e.g., ram body; metal body). InFIG. 2, the RCD system44is in an open configuration62(e.g., default configuration) in which the first ram assembly50and the second ram assembly56are withdrawn or retracted from a bore64(e.g., central bore) of the RCD system44, do not contact the tubular36, and/or do not contact one another.

The RCD system44includes a housing66(e.g., body) surrounding the bore64. The housing66also defines a first cavity70that supports the first ram assembly50and a second cavity72that supports the second ram assembly56. A central axis of the bore64extends along the vertical axis2, while a central axis of the first cavity70and the second cavity72extends along the longitudinal axis4and is transverse (e.g., orthogonal) to the central axis of the bore64. Thus, as the first ram assembly50and the second ram assembly56move (e.g. slide) within the first cavity70and the second cavity72, respectively, the first ram assembly50and the second ram assembly56move along the longitudinal axis4into and out of the bore64.

The housing66is generally rectangular in the illustrated embodiment, although the housing66may have any cross-sectional shape, including any polygonal shape or an annular shape. A plurality of bonnet assemblies80are mounted to the housing66(e.g., via threaded fasteners). In the illustrated embodiment, first and second bonnet assemblies80are mounted to opposite sides of the housing66. Each bonnet assembly80supports an actuator82(e.g., actuator assembly), which may include a piston84and a connecting rod86. In the open configuration62, the first ram assembly50is generally adjacent to a first end of the housing66and the second ram assembly56is generally adjacent to a second end88, opposite the first end along the longitudinal axis4, of the housing66. As shown, in the open configuration62, the first ram assembly50and the second ram assembly56are on opposite sides of the bore64along the longitudinal axis4. Then, in operation, the actuators82may drive the first ram assembly50and the second ram assembly56toward one another along the longitudinal axis4and through the bore64to contact the tubular36to seal the bore64to reach a closed configuration.

The first packer52and the second packer58may together form a seal element90that is configured to form an annular seal about the tubular36within the bore64at least while the first ram assembly50and the second ram assembly56are in the closed configuration. The first packer52and the second packer58may each have an arc cross-sectional shape (e.g., 180 degree arc). For example, the first packer52and the second packer58may each have a semicircular cross-sectional shape with a curved central groove (e.g., semicircular groove or cut-out portion) that is configured to receive and to seal about a half of the tubular36. Thus, when the first ram assembly50and the second packer assembly56are driven into the bore64, the respective ends of the first packer52and the second packer58contact one another, and the first packer52and the second packer58form the annular seal about the tubular36.

FIG. 3is a is a cross-sectional top view of a portion of the RCD system44ofFIG. 2, wherein the RCD system is in a closed configuration100. In the closed configuration100, the first ram assembly50and the second ram assembly56are positioned within the bore64, contact the tubular36, and/or contact one another. In particular, the respective ends of the first packer52and the second packer58contact one another, and the first packer52and the second packer58form the annular seal about the tubular36. As shown, the first ram54and the second ram60may have corresponding curvatures (e.g., curved surfaces facing the first packer52and the second packer58, respectively). The RCD system44may be adjusted from the open configuration62ofFIG. 2to the closed configuration100ofFIG. 3(and vice versa) via operation of the actuators82ofFIG. 2(e.g., by providing a hydraulic fluid to drive the pistons84).

As shown inFIGS. 2 and 3, the RCD system44may include a bearing assembly102. In particular, the first ram assembly50may include a first bearing104(e.g., first bearing portion; curved bearing portion) of the bearing assembly102, and the second ram assembly56may include a second bearing106(e.g., second bearing portion; curved bearing portion) of the bearing assembly102. The first bearing104may be positioned between (e.g., radially between) a radially-inner curved surface of the first ram54and a radially-outer curved surface of the first packer52, and the second bearing106may be positioned between (e.g., radially between) a radially-inner curved surface of the second ram60and a radially-outer curved surface of the second packer58. When the first ram assembly50and the second ram assembly56are driven into the bore64, the respective ends of the first bearing104and the second bearing106contact one another to form an annular bearing structure that enables rotation of the seal element90(e.g., formed by the first packer52and the second packer58) relative to the first ram54and the second ram60. Thus, while the RCD system44is in the closed configuration100in which the seal element90seals against the tubular36, the seal element90may rotate with the tubular36(e.g., be driven to rotate via rotation of the tubular36). In some embodiments, the bearing assembly102may be used with or may be replaced by lubricant applied between the curved surfaces, and the lubricant may enable the rotation of the seal element90. The first packer52and the second packer58may rotate together in the circumferential direction6. Thus, at certain times during the rotation, the first packer52may rotate to be positioned between the second ram60and the second packer58along the longitudinal axis4, while the second packer58may rotate to be positioned between the first ram54and the first packer52. For example, at certain times during the rotation, the first packer52and the second packer58may change or swap places as compared to the places shown inFIG. 2and may rotate continuously in the circumferential direction6.

In some embodiments, the RCD system44may include one or more retaining features108that are configured to block rotation of the first packer52relative to the first ram54and to block rotation of the second packer58relative to the second ram60. The one or more retaining features108may include one or more shear pins that extend radially between the first packer52and the first ram54and one or more shear pins that extend radially between the second packer58and the second ram60. The one or more shear pins may block the rotation of the first packer52and the second packer58until the first packer52and the second packer58seal against the tubular36as the tubular36rotates. Then, the one or more shear pins may break due to the rotational force exerted by the tubular36on the first packer52and the second packer58as the tubular36rotates. Once the one or more shear pins break, the first packer52and the second packer58may rotate with the tubular36as the tubular36rotates.

In some embodiments, the one or more retaining features108may include one or more actuatable locks that may extend radially between the first packer52and the first ram54and one or more actuatable locks that extend radially between the second packer58and the second ram60. The one or more actuatable locks may block the rotation until adjusted (e.g., from a locked configuration to an unlocked configuration; via electronic control by an electronic controller) so as not to extend radially between the components in this manner. Then, the first packer52and the second packer58may rotate with the tubular36as the tubular36rotates. In some embodiments, the one or more actuatable locks may be adjusted automatically in response to the first ram assembly50and the second ram assembly56being driven toward and/or reaching the closed configuration100. In some embodiments, the one or more retaining features108(e.g., the actuatable locks) may enable the RCD system44to operate to seal about the tubular36without rotation of the first packer52or the second packer58relative to the first ram54and the second ram60(e.g., the RCD system44may operate as a BOP having pipe rams that seal against the tubular36without rotation of the first packer52or the second packer58relative to the first ram54and the second ram60). This may be particularly useful during drilling operations or other types of operations in which the tubular36does not rotate within the bore64; however, this may be useful regardless of whether the tubular36rotates within the bore64. It should be appreciated that the one or more retaining features108may have any suitable form to enable the disclosed techniques.

FIG. 4is a cross-sectional side view of the portion of the RCD system44ofFIG. 3, wherein the RCD system44is in the closed configuration100. As shown, in some embodiments, the radially-inner curved surface of the first ram54and the radially-outer curved surface of the first packer52may have a corresponding taper. Similarly, the radially-inner curved surface of the first ram54and the radially-outer curved surface of the first packer52may have a corresponding taper. For example, a vertically-upper end110of the radially-inner curved surfaces and the radially-outer curved surfaces may be configured to be positioned further from the bore64along the longitudinal axis4as compared to a vertically-lower end112(e.g., vertically below the vertically-upper end110relative to a wellbore and along a gravity vector) of the radially-inner curved surfaces and the curved radially-outer surfaces. As shown, the corresponding taper may be a gradual, continuous taper from the vertically-upper end110to the vertically-lower end112. However, the corresponding taper may only extend along a portion of the interface between the vertically-upper end110and the vertically-lower end112and/or the corresponding taper may include a stepped interface (e.g., stepped surfaces having alternatively longitudinally-facing and vertically-facing surfaces). The corresponding taper may enable the first ram54to provide support to the first packer52along the vertical axis2and may enable the second ram58to provide support to the second packer58along the vertical axis2. Thus, the corresponding taper may retain the first packer52within the first ram54and may retain the second packer58within the second ram60(e.g., block the first packer52and the second packer58from falling or sliding along the vertical axis2(e.g., toward the wellbore; due to gravity). Additionally, the corresponding taper may facilitate maintenance operations, such as inspection, repair, or replacement of the first packer52and the second packer58.

InFIGS. 2-4, the first packer52and the second packer58may be retained on the first ram54and the second ram60, respectively, due to the one or more retaining features108and/or the corresponding taper. It is presently recognized that various arrangements of components and/or techniques for assembly of the components may be desirable, such as to facilitate various operations (e.g., maintenance operations; sealing operations) with the RCD system44ofFIG. 1. With the foregoing in mind,FIGS. 5-9illustrate various arrangements of components of the RCD system44ofFIG. 1, as well as techniques for assembly of the components.

FIG. 5is a cross-sectional side view of a portion of the RCD system44that may be used in the drilling system10ofFIG. 1. InFIG. 5, a first packer assembly130is configured to couple to a first ram132via a first stab connection134(e.g., key-slot connection) to form a first ram assembly136, and a second packer assembly140is configured to couple to a second ram142via a second stab connection144(e.g., key-slot connection) to form a second ram assembly146. Together, the first packer assembly130and the second packer assembly140form a seal element assembly150.

As shown, the first packer assembly130includes a first packer152, a first bearing154(e.g., first bearing portion), a frame156, and a respective stab feature158. Similarly, the second packer assembly140includes a second packer162, a second bearing164(e.g., second bearing portion), a frame166, and a respective stab feature168. The first ram132may include a respective stab feature170that is configured to engage (e.g., via a stab connection) the respective stab feature158of the first packer assembly130, and the second ram142may include a respective stab feature172that is configured to engage (e.g., via a stab connection) the respective stab feature168of the second packer assembly140. It should be appreciated that multiple stab features and multiple stab connections may be provided between the first packer assembly130and the first ram132and/or between the second packer assembly140and the second ram142(e.g., distributed along the circumferential axis6and/or the vertical axis2).

The first packer assembly130and the second packer assembly140may be assembled onto the first ram132and the second ram142, respectively, during manufacturing operations prior to installation of the RCD system44at a wellsite or at the wellsite. For example, to assemble the components at the wellsite, the first packer assembly130and the second packer assembly140may be lowered into the bore via a tool (e.g., running tool; installation tool) until the first packer assembly130and the second packer assembly140are aligned with the first ram132and the second ram142along the vertical axis2. Once aligned, the first ram132and the second ram142may be driven (e.g., via actuators) toward the bore to form the stab connections134,144to thereby coupled the first packer assembly130to the first ram132and the second packer assembly140to the second ram142. Additionally or alternatively, the tool may be configured to drive the first packer assembly130and the second packer assembly140toward the first ram132and the second ram142, respectively, to form the stab connections134,144to thereby couple the first packer assembly130to the first ram132and the second packer assembly140to the second ram142. The seal element assembly150may be coupled to the first ram132and the second ram142while the tubular is in the bore or while the tubular is not in the bore (e.g., the bore is empty).

InFIG. 5, the seal element assembly150formed by the first packer assembly130and the second packer assembly140is in a disengaged configuration180in which the first packer assembly130is not coupled to the first ram132and the second packer assembly140is not coupled to the second ram142. InFIG. 6, the seal element assembly150formed by the first packer assembly130and the second packer assembly140is in an engaged position182in which the first packer assembly130is coupled to the first ram132via the stab connection134to form the first ram assembly136, and the second packer assembly140is coupled to the second ram142via the stab connection144to form the second ram assembly146.

Furthermore,FIG. 7is a cross-sectional side view of the portion of the RCD system44ofFIG. 5, wherein the RCD system44is in the closed configuration100in which the seal element assembly150seals against the tubular36. As shown inFIGS. 5-7, the first packer assembly130may include the first bearing154to enable the first packer152to rotate relative to the frame156of the first packer assembly130and/or relative to the first ram132and the second packer assembly140may include the second bearing164to enable the second packer162to rotate relative to the frame166of the second packer assembly140and/or relative to the second ram142. To move to the closed configuration100ofFIG. 7, the first ram assembly136and the second ram assembly146may be driven into the bore along the longitudinal axis4via actuators.

It should be appreciated that the first packer152and the second packer162may each have an arc shape in a cross-section taken in a plane parallel to the longitudinal axis4(e.g., from a top view), similar to or the same as the arc shape illustrated inFIGS. 2-4. Furthermore, the first ram132and the second ram142may have a corresponding curved shaped (e.g., radially-inner curved surface) to mate with the first packer assembly130and the second packer assembly140, respectively. While the first packer assembly130and the first ram132, as well as the second packer assembly140and the second ram142, are not shown to have a corresponding taper along the vertical axis2(e.g., similar toFIG. 4), it should be appreciated that the components may be modified to provide the corresponding taper or similar interface (e.g., stepped interface) to provide further support to the first packer assembly130and the second packer assembly140along the vertical axis2.

The first packer assembly130and the second packer assembly140may be separated from the first ram132and the second ram142, respectively, via the tool. For example, as the tool engages the first packer assembly130and the second packer assembly140, the first ram132and the second ram142may be retracted or withdrawn from the bore via the actuators to thereby break the stab connections. The tool may then pull the first packer assembly130and the second packer assembly140along the vertical axis2away from the first ram132and the second ram142.

In some embodiments, the RCD system ofFIGS. 5-7may include one or more retaining features (e.g., shear pins, actuatable locks) similar to the one more retaining features discussed above with respect toFIGS. 2-4. In such cases, the one or more retaining features may be incorporated into the first packer assembly130and the second packer assembly140(e.g., extend radially between the respective frame156,166and the respective packer152,162) to block rotation of the first packer152and the second packer162until the one or more retaining features are removed (e.g., via shearing due to rotation of the tubular36; via actuation). Thus, in some embodiments, the RCD system44may be configured to operate to seal about the tubular36without rotation of the first packer152or the second packer162relative to the first ram132and the second ram142(e.g., the RCD system44may operate as a BOP having pipe rams that seal against the tubular36without rotation of the first packer152or the second packer162relative to the first ram132and the second ram142). This may be particularly useful during drilling operations or other types of operations in which the tubular36does not rotate within the bore; however, this may be useful regardless of whether the tubular36rotates within the bore. It should be appreciated that the one or more retaining features may have any suitable form to enable the disclosed techniques.

Furthermore, the stab connections134,144may facilitate efficient transition of the RCD system44for use as an RCD device (e.g., having the seal element assembly150that seals about and rotates with the tubular36) and for use as a BOP (e.g., having a seal element that seals the bore without rotation of the seal element). For example, upon removal of the first packer assembly130and the second packer assembly140, the first ram132and the second ram142may be used as the BOP. In some such cases, the first ram132and the second ram142may be configured to couple (e.g., via the respective stab features170,172) to additional packer assemblies that are configured to enable such operations or any of a variety of other operations. In some embodiments, the change in the packer assemblies may be carried out at the wellsite and without removal of the first ram132and the second ram142from the housing of the RCD system44.

FIG. 8is a cross-sectional side view of a portion of the RCD system44that may be used in the drilling system ofFIG. 1. InFIG. 8, the first packer assembly130is configured to couple to the first ram132via the first stab connection134(e.g., key-slot connection) to form the first ram assembly136, and the second packer assembly140is configured to couple to the second ram142via the second stab connection144(e.g., key-slot connection) to form the second ram assembly146. Together, the first packer assembly130and the second packer assembly140form the seal element assembly150.

As shown, the first stab connection134is formed between vertically-facing surfaces of the first packer assembly130and the first ram132, and the second stab connection144is formed between vertically-facing surfaces of the second packer assembly140and the second ram142. The first packer assembly130and the second packer assembly140may be assembled onto the first ram132and the second ram142, respectively, during manufacturing operations prior to installation of the RCD system44at a wellsite or at the wellsite. For example, to assemble the components at the wellsite, the first ram132and the second ram142may be driven toward and positioned in the bore. Then, the first packer assembly130and the second packer assembly140may be lowered into the bore via a tool (e.g., running tool; installation tool) until the first packer assembly130and the second packer assembly140are stabbed into the first ram132and the second ram142along the vertical axis2.

InFIG. 8, the seal element assembly150formed by the first packer assembly130and the second packer assembly140is in the disengaged configuration180in which the first packer assembly130is not coupled to the first ram132and the second packer assembly140is not coupled to the second ram142. InFIG. 9, the seal element assembly150formed by the first packer assembly130and the second packer assembly140is in the engaged position182in which the first packer assembly130is coupled to the first ram132via the stab connection134to form the first ram assembly136, and the second packer assembly140is coupled to the second ram142via the stab connection144to form the second ram assembly146.

FIG. 10is a cross-sectional side view of the portion of the RCD system44ofFIG. 8, wherein the RCD system44is in the closed configuration100in which the seal element assembly150seals against the tubular36. As shown inFIGS. 8-10, the first packer assembly130may include the first bearing154to enable the first packer152to rotate relative to the frame156of the first packer assembly130and/or relative to the first ram132and the second packer assembly140may include the second bearing164to enable the second packer162to rotate relative to the frame166of the second packer assembly140and/or relative to the second ram142. To move to the closed configuration100ofFIG. 10, the first ram assembly136and the second ram assembly146may be driven into the bore along the longitudinal axis4via actuators.

It should be appreciated that the first packer152and the second packer162may each have an arc shape in a cross-section taken in a plane parallel to the longitudinal axis4(e.g., from a top view), similar to or the same as the arc shape illustrated inFIGS. 2-4. Furthermore, the first ram132and the second ram142may have a corresponding curved shaped (e.g., radially-inner curved surface) to mate with the first packer152and the second packer162, respectively. While the first packer assembly130and the first ram132, as well as the second packer assembly140and the second ram142, are not shown to have a corresponding taper along the vertical axis2(e.g., similar toFIG. 4), it should be appreciated that the components may be modified to provide the corresponding taper or a similar interface (e.g., stepped interface, such that a portion of the first ram132is circumferentially about the first packer assembly130when connected to one another and a portion of the second ram142is circumferentially about the second packer assembly140when connected to one another) to provide further support to the first packer assembly130and the second packer assembly140along the vertical axis2and/or the longitudinal axis4. The first packer assembly130and the second packer assembly140may be separated from the first ram132and the second ram142, respectively, via the tool. For example, the tool may engage and pull the first packer assembly130and the second packer assembly140along the vertical axis2away from the first ram132and the second ram142.

In some embodiments, the RCD system ofFIGS. 8-10may include one or more retaining features (e.g., shear pins, actuatable locks) similar to the one more retaining features discussed above with respect toFIGS. 2-4. In such cases, the one or more retaining features may be incorporated into the first packer assembly130and the second packer assembly140(e.g., extend radially between the respective frame156,166and the respective packer152,162) to block rotation of the first packer152and the second packer162until the one or more retaining features are removed (e.g., via shearing upon rotation of the tubular36; via actuation). Thus, in some embodiments, the RCD system44may be configured to operate to seal about the tubular36without rotation of the first packer152or the second packer162relative to the first ram132and the second ram142(e.g., the RCD system44may operate as a BOP having pipe rams that seal against the tubular36without rotation of the first packer152or the second packer162relative to the first ram132and the second ram142). This may be particularly useful during drilling operations or other types of operations in which the tubular36does not rotate within the bore; however, this may be useful regardless of whether the tubular36rotates within the bore. It should be appreciated that the one or more retaining features108may have any suitable form to enable the disclosed techniques.

Furthermore, the stab connections may facilitate efficient transition of the RCD system44for use as an RCD device (e.g., having the seal element assembly150that seals about and rotates with the tubular36) and for use as a BOP (e.g., having a seal element that seals the bore without rotation of the seal element). For example, upon removal of the first packer assembly130and the second packer assembly140, the first ram132and the second ram142may be used as the BOP. In some such cases, the first ram132and the second ram142may be configured to couple (e.g., via the respective stab features170,172) to additional packer assemblies that are configured for such operations. In some cases, the first ram132and the second ram142may each have a BOP packer (e.g., at surfaces184of the first ram132and the second ram142that face the bore) that is positioned so that the first packer assembly130and the second packer assembly140do not interfere with the BOP packers even while the first packer assembly130and the second packer assembly140are coupled to the first ram132and the second ram142, respectively.

FIG. 11is a flow diagram of an embodiment of a method200of operating an RCD system, such as the RCD system44, that may be used in the drilling system ofFIG. 1. In step202, a first packer may be coupled to a first ram of the RCD system. The first packer and the first ram may form a first ram assembly. The first packer and the first ram may be coupled to one another in any of a variety of ways, such as via a corresponding taper or other interface formed by corresponding surfaces (e.g., stepped surfaces), one or more retaining features, and/or a stab connection.

In step204, a second packer may be coupled to a second ram of the RCD system. The second packer and the second ram may form a second ram assembly. The second packer and the second ram may be coupled to one another in any of a variety of ways, such as via a corresponding taper or other interface formed by corresponding surfaces, one or more retaining features, and/or a stab connection.

In step206, the first ram (and the first packer coupled thereto) and the second ram (and the second packer coupled thereto) may be driven toward one another and into a bore to cause the first packer and the second packer to seal (e.g., to form an annular seal) against a tubular in the bore.

In step208, the first packer and the second packer may rotate relative to the first ram and the second ram as the tubular rotates. For example, the first packer and the second packer may be supported on bearings that enable such rotation. As noted above, such rotation may be initially blocked (e.g., via shear pins) or selectively blocked (e.g., via actuatable locks), and any of a variety of one or more retaining features may be utilized to block or to otherwise limit the rotation of the first packer and the second packer.

In step210, the first ram (and the first packer coupled thereto) and the second ram (and the second packer coupled thereto) may be driven away from one another (e.g., withdrawn) and out of the bore to cause the first packer and the second packer to break contact (e.g., to break the annular seal) against the tubular in the bore. In some embodiments, the first packer and the second packer may be separated from the first ram and the second ram, respectively, such as via a tool. However, in some embodiments, the first packer and the second packer may remain in place for future RCD operations. In some embodiments, the first ram and the second ram may be coupled to (e.g., at the same time as the first packer and the second packer, or only at different times as the first packer and the second packer) additional packers that may be used for future BOP operations. For example, the additional packers, the first packer, and the second packer may be coupled to the first ram and the second ram using the same connections (e.g., the same stab features) or different connections.

It should be appreciated that all of the features discussed above with respect toFIGS. 1-11may be combined in any suitable manner. Additionally, various modifications are envisioned. For example, while the seal element and the seal element assembly are illustrated as two physically separate components that are independently coupled to a respective ram, the seal element or the seal element assembly may be an annular component (e.g., gaplessly continuous ring) and the rams may compress the annular component (e.g., reduce an inner diameter of the annular component) to adjust the seal about the tubular36.