RCD sealing element assembly

Abstract

A rotating control device (RCD) includes an inner housing rotatably mounted within an outer housing and a sleeve assembly movably held within the inner housing by connection elements. The sleeve assembly includes anchors provided at axial ends of a sleeve, where the anchors are positioned in annular receptacles at corresponding sides of the inner housing. Each connection element includes a shaft having a connection end connected to an anchor and a spacer portion extending from the connection end, through a connection passage formed through a wall of the inner housing. When the sleeve is energized, an axial end of the sleeve assembly and a connected connection element axially moves a float distance relative to the inner housing wall.

Description

PATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1TITLE: RCD SEALING ELEMENT ASSEMBLYINVENTORS: Manuel GARIBAY Katie A. KOTAREK Hunter S. HAEBERLE David A. WALLACEPATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1RCD SEALING ELEMENT ASSEMBLYBACKGROUND

[0001] Rotating control devices (RCDs) are used to contain and redirect annular flow of fluids through a well. An RCD is typically positioned at the top of a blowout preventer (BOP). When installed, the RCD seals around a rotating drill pipe. One or more controlled flowlines may be provided below the seal, through which fluids from the well may be diverted.

[0002] FIG. 1 shows an example of a generic RCD 100 mounted at the top side of a BOP 110, for use in one or more operations of a well 101. The RCD 100 includes an outer housing 102 that may be bolted to the BOP 110 or other connecting component. The RCD further includes an inner rotating housing 104 rotatably mounted within in the outer housing 102 using one or more bearing assemblies. One or more sealing elements 106 (e.g., strippers) are connected to the inner rotating housing 104. The sealing elements 106 contact and seal against drill pipe 120 as the drill pipe 120 is extended into and rotated within the well 101. The RCD 100 may be driven by a Kelly or other assembly to rotate the inner rotating housing 104 with the drill pipe 120.

[0003] Due to the stresses and / or harsh environments RCD sealing elements are exposed to, the sealing elements may be replaced from time to time. Additionally, other operational considerations may necessitate removal and / or disassembly of an RCD. However, due to the functional requirements of an RCD (e.g., being fixedly mounted to other well equipment and maintaining a seal with drill pipe as it is lowered into and rotated in a well), disassembly of the RCD is typically complex and burdensome.SUMMARY

[0004] This summary is provided to introduce a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.PATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1

[0005] In one aspect, embodiments disclosed herein relate to sleeve assemblies for use with rotating control devices (RCDs) and / or other dynamic sealing assemblies. Sleeve assemblies according to embodiments disclosed herein may include a sleeve having a polymeric body with varying thickness between an inner surface and an outer surface. The varying thickness may include transition surfaces formed along the sleeve’s inner surface, where the transition surfaces may slope radially outward from axial ends of an inner protruding surface. The sleeve may have grooves formed in the inner surface and / or a straight reinforcement member within the polymeric body extending axially from a first end to a second end of the polymeric body. In some embodiments, the inner surface of the sleeve may protrude away from the reinforcement member at an angle compatible with an angle of a drill pipe connection entry and exit angle. The sleeve assembly may include a first anchor attached to the first end of the polymeric body and a second anchor attached to the second end of the polymeric body, where the first and second anchors are configured to secure the sleeve to a sealing assembly housing (e.g., an inner housing of an RCD). One or both of the anchors may be movably connected to the sealing assembly housing using connection element(s) that are comiected to the anchor(s) in a manner that allows limited axial movement of the connected anchor(s) relative to the sealing assembly housing. For example, the connection element and / or a connection passage receiving the connection element may have a size (e.g., length) that is selected to limit the relative axial movement between the connected anchor(s) and sealing assembly housing.

[0006] In another aspect, embodiments disclosed herein relate to sleeve assemblies having one or more reinforcement members formed within the sleeve’s polymeric body and methods of their assembly. In some embodiments, the reinforcement member(s) may be formed within the sleeve’s polymeric body by molding the polymeric material (e.g., an elastomeric material) around the reinforcement member(s). The reinforced sleeve may be connected at opposite axial ends to an inner rotatable housing, such that the reinforced sleeve rotates with the inner rotatable housing.

[0007] In another aspect, embodiments herein are directed to an RCD including an outer housing, an inner housing rotatably mounted within the outer housing, and a sleeve assembly movably held within the inner housing by connection elements. The inner housing includes a first annular receptacle and a second annular receptaclePATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1 positioned at opposite sides of the inner housing. The sleeve assembly includes a sleeve, a first anchor at a first axial end of the sleeve, and a second anchor at an opposite, second axial end of the sleeve, where the first anchor is positioned in the first annular receptacle of the inner housing, and the second anchor is positioned in the second annular receptacle of the inner housing. The connection elements each have a shaft with a connection end connected to one of the first anchor or the second anchor, where a spacer portion of the shaft extends from the connection end through a connection passage formed through a wall of the inner housing. An annular seal may be positioned between the first anchor and an imier surface of the first annular receptacle. Additionally, an annular seal may be positioned between the second anchor and an inner surface of the second annular receptable. A fluid annulus may be formed between the sleeve’s outer surface and the inner housing, where the annular seals may seal the axial ends of the fluid annulus. A fluid pressure within the fluid annulus may be increased (e.g., by directing fluid from a fluid source through one or more ports to the fluid annulus) to constrict the sleeve radially inward, which may energize the sleeve to seal around an object (e.g., a pipe). Because the sleeve seal may be actively adjusted by adjusting the fluid pressure in the fluid annulus, such sealing may be referred to as “active” sealing, and such assembly may be referred to as an “active” sealing assembly. By movably connecting the sleeve within the inner housing, one or both of the axial ends of the sleeve may axially move a pre-selected float distance as the sleeve is constricted radially inward from increased fluid pressure within the fluid annulus. In another aspect, embodiments herein are directed to a method including installing a sleeve assembly having a sleeve in an inner housing of a rotating control device (RCD), the installing including inserting a connection element through a base wall of the inner housing; and connecting a connection end of the connection element to an axial end of the sleeve assembly, where the connection element comprises a mechanical stop positioned on a side of the base wall opposite the connection end, and energizing the sleeve, where during energizing, the axial end of the sleeve assembly and the connected connection element axially moves a float distance. A like-type float connection may also be provided at an opposite axial end of the sleeve assembly.PATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1

[0009] Other aspects and advantages of the claimed subject matter will be apparent from the following description and the appended claims.BRIEF DESCRIPTION OF DRAWINGS

[0010] Wherever possible, like or identical reference numerals are used in the figures to identify common or the same elements. The figures are not necessarily to scale, and certain features and certain views of the figures may be shown exaggerated in scale for purposes of clarification.

[0011] FIG. 1 shows a conventional RCD assembled in a well system.

[0012] FIG. 2A shows a cross-sectional view of an RCD in accordance with embodiments of the present disclosure.

[0013] FIG. 2B shows a detailed and partial view of a sleeve assembly in the RCD of FIG. 2A in accordance with embodiments of the present disclosure.

[0014] FIG. 2C shows a cross-sectional view of annular seals used with RCD assemblies in accordance with embodiments of the present disclosure.

[0015] FIG. 3A shows a cross-sectional area of an inactivated sleeve encompassing a drill string in accordance with embodiments of the present disclosure.

[0016] FIG. 3B shows a cross-sectional area of an activated sleeve encompassing a drill string in accordance with embodiments of the present disclosure.

[0017] FIG. 4A shows a partial / close-up cross-sectional area of a sleeve assembly of FIG. 3A wherein the sleeve is not activated in accordance with embodiments of the present disclosure.

[0018] FIG. 4B shows a partial / close-up cross-sectional area of a sleeve assembly of FIG. 3B wherein the sleeve is activated in accordance with embodiments of the present disclosure.

[0019] FIGs. 5A-C show partial cross-sectional views and a partial front view of a sleeve assembly mounted in a floating configuration to an inner housing according to embodiments of the present disclosure.PATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1

[0020] FIG. 6 shows a partial cross-sectional view of a sleeve assembly mounted in a floating configuration to an RCD inner housing according to embodiments of the present disclosure.

[0021] FIG. 7A is a detailed and partial view of a sleeve assembly in an RCD according to embodiments of the present disclosure.

[0022] FIG. 7B shows a cross-sectional view of the sleeve in the sleeve assembly of FIG. 7A in accordance with embodiments of the present disclosure.

[0023] FIG. 7C shows cross-sectional view of a sleeve in a sleeve assembly in accordance with embodiments of the present disclosure.

[0024] FIG. 7D shows a cross-sectional view of another sleeve according to embodiments of the present disclosure.

[0025] FIG. 7E shows a cross-sectional view of another sleeve according to embodiments of the present disclosure.

[0026] FIG. 8A shows a cross-sectional view of a sleeve having grooves formed therein according to embodiments of the present disclosure.

[0027] FIG. 8B shows an example of a groove formed in a sleeve according to embodiments of the present disclosure.

[0028] FIGs. 9A-B show a sleeve assembly under pressure in accordance with one or more embodiments.DETAILED DESCRIPTION

[0029] Embodiments disclosed herein relate generally to RCDs and sleeve-type sealing assemblies used in RCDs. Some embodiments disclosed herein relate to the structure of an RCD sealing assembly, which may include sleeve assemblies for RCDs that allow for proper sealing around a drill string, including drill pipe connections.

[0030] According to embodiments of the present disclosure, RCDs may include, generally, an inner housing rotatably mounted within an outer housing and a sleeve assembly connected within the inner housing. The sleeve assembly may be connectedPATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1 within the inner housing of an RCD in a configuration that allows the sleeve assembly to contact and seal against a drill string extending through the RCD (e.g., by providing the sleeve assembly with an imier diameter corresponding to an anticipated outer diameter of the drill string), and that allows the sleeve assembly and inner housing to rotate together within the outer housing when the sleeve assembly is sealed against a rotating drill string (e.g., via bearing assemblies).

[0031] Sleeve assemblies according to embodiments of the present disclosure may include a polymeric sleeve having a generally tubular-shaped body, which may be connected at opposite axial ends to an inner housing of an RCD. An activation fluid may be injected in a fluid annulus around the outer surface of the sleeve to constrict the sleeve radially inward. The sleeve may be constricted radially inward to contact and seal against a drill string as the drill string is moved through and rotated within the RCD. Such assemblies and sealing methods may be referred to as “active” sealing assemblies and methods.

[0032] An example of an RCD 201 according to embodiments of the present disclosure is shown in FIG. 2A-C. FIG. 2A shows a cross-sectional view of the RCD 201 taken along a longitudinal plane extending through the longitudinal axis 204 of the RCD 201. FIG. 2B shows a detailed and partial view of the sleeve assembly 200 in the RCD 201. FIG. 2C shows a cross-sectional view of the sleeve in the sleeve assembly 200 taken along a plane transverse to the longitudinal axis 204 of the sleeve assembly 200.

[0033] The RCD 201 includes an inner housing 203 rotatably mounted within an outer housing 202 (e.g., using one or more bearing assemblies positioned between the inner and outer housings). In FIG. 2A, the outer housing 202 and inner housing 203 are shown using simplified shapes to represent the housing bodies as having generally cylindrical shapes. However, outer and inner housings of RCDs may have various shapes, types, and sizes of bodies, depending on, for example, the equipment to which the RCD is to be mounted, the size of the drill string to be used, operating conditions, and manufacturing considerations. For example, in some embodiments, the outer housing may be part of a drilling riser. Further, inner and outer housings of an RCD may be formed of different types of materials known in the art, such as metalPATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1 composite materials, and may be selected based on the intended application (e.g., subsea application or surface application).

[0034] According to embodiments of the present disclosure, an outer housing may have a body with a generally cylindrical cavity formed therein designed to hold an inner housing, where the cavity is communicated with the exterior of the outer housing via openings formed at opposite axial ends of the outer housing. The openings in the outer housing may provide an inlet and outlet through which a drill string may be passed. Similarly, the inner housing may have an interior cavity that is communicated with the exterior of the inner housing via openings formed at opposite axial ends of the inner housing. When the inner housing 203 is mounted within the outer housing 202, the openings at the opposite axial ends of the inner and outer housings 203, 202 are aligned to provide a drill string passage through the RCD, where a drill string may be passed through the drill string passage of the RCD during operation.

[0035] The RCD 201 further includes a sleeve assembly 200 according to embodiments of the present disclosure connected to the inner housing 203. The sleeve assembly 200 may include a sleeve 240 having a generally tubular-shaped polymeric body, which may be connected to the inner housing 203 in a coaxial position with the openings in the inner and outer housings, such that the sleeve 240 partially defines the drill string passage through the RCD 201.

[0036] Sleeves may be connected to an inner housing of an RCD, for example, using anchors provided at the opposite axial ends of the sleeve, where the anchors may be connected to the inner housing, leaving the portion of the sleeve extending between the two axial ends free to move radially inward to contact and seal a drill string during operation.

[0037] For example, in the embodiment shown in FIGs. 2A-B, the sleeve assembly 200 has a first anchor 210 and a second anchor 270 connected at opposite axial ends of the sleeve 240. The anchors 210, 270 may be metal components, e.g., metal inserts, having an interlocking interface with the sleeve. In some embodiments, anchors may be connected to a sleeve by forming the sleeve around the anchors in a mold, where the anchors may be positioned at axial ends of the mold, and the sleeve body material may be poured in the mold between the anchors to be molded in place between the anchors. In some embodiments, anchors may be fitted at opposite axial ends of a preformedPATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1 sleeve, where an interlocking interface (e.g., formed by mating tongues and grooves) between the anchors and the sleeve may at least partially secure the sleeve to the anchors. In one or more embodiments, the anchors 210, 270 may be annular components that extend the entire angular distance around the axial ends of the sleeve 240. As such, the anchors may sometimes be referred to as end rings.

[0038] The anchors may provide a mechanical interface between the sleeve and inner housing (rotor), where anti-rotation feature(s) may ensure that the entire inner housing rotates with the sleeve when it is closed onto the drill string. In some embodiments, the anchors may provide an interface and / or a mechanical stop mechanism that allows the anchors to axially move (float) relative to the inner housing without rotating relative to the inner housing.

[0039] Each anchor 210, 270 may be connected to the inner housing 203 of the RCD 201 to thereby secure the connected sleeve 240 to the inner housing 203, e.g., by interference fit, welding, and / or fasteners. For example, anchors may be inserted into annular receptacles formed in the inner housing, where the anchors and annular receptacles may have corresponding sizes that allow the anchors to be slid into / out of the corresponding receptacle. In the embodiment shown in FIG. 2A-B, a first anchor 210 is connected to a first axial end 205 of the sleeve 240 and inserted into a first receptacle 212 of the inner housing 203 to secure the first axial end 205 of the sleeve 240 to the imier housing 203. A second anchor 270 is connected to a second axial end 275 of the sleeve 240 and inserted into a second receptacle 272 of the inner housing 203 to secure the second axial end 275 of the sleeve 240 to the inner housing 203. In some embodiments, anchors of a sleeve assembly may be connected to an inner housing, or other mechanical features, e.g., using fasteners such as bolts.

[0040] The sleeve assembly 200 may be connected to the imier housing 203 at opposite axial ends of the sleeve assembly 200 to fluidly seal the axial ends of a fluid annulus 245 formed between the sleeve assembly 200 and the inner housing 203. The axial ends of the sleeve assembly 200 may be fluidly sealed to the inner housing 203 via one or more seals (e.g., an o-ring or similar mounted into the anchor) and / or by interference fit of the axial end into the annular receptacle. For example, in FIG. 2A, first inner and outer annular seals 235, 236 may be used to fluidly seal the first axial end of the sleeve assembly in the first receptacle 212, and second inner and outerPATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1 annular seals 265 may be used to fluidly seal the second axial end of the sleeve assembly in the second receptacle 272. In one or more embodiments, an activation fluid (e.g., a hydraulic fluid) may be provided from a volume-compensated annulus, e.g., in the outer housing, to fill the fluid annulus 245 and exert external pressure on the sleeve assembly 200. In one or more embodiments, fluid may be filled into the fluid annulus 245 via one or more valved or other flow-controlled lines.

[0041] External pressure may be exerted from fluid in the fluid annulus 245 to an outer surface 220 of the sleeve assembly 200 to activate and constrict the sleeve 240 radially inward. In such manner, the sleeve 240 may be constricted to contact and seal against a drill string 298 as the drill string 298 is rotated and moved through the RCD 201.

[0042] A standard drill string typically contains pipe segments connected together in an end-to-end fashion at drill pipe connections. Each pipe segment may have a male joint (also referred to as a pin end) at one axial end and a female joint (also referred to as a box end) at an opposite axial end. The male joint may have threads formed around its outer surface (e.g., American Petroleum Institute (API) threads or proprietary-sized threads), and the female joint may have correspondingly sized threads formed around its inner surface. The female joint of one pipe segment may be threaded to the male joint of an adjacent pipe segment, where the threaded together male and female joints form the drill pipe connection. The wall thickness of the pipe body may be increased (referred to as an upset) at the joint to ensure proper strength of the joint. For example, pipe segments may have an internal upset where an increased thickness is provided along the inside diameter to compensate for the pipe material removed in the threading (where the outer surface profile may be straight along the internal upset), an external upset where an increased thickness is provided along the outer diameter to compensate for the pipe material removed in the threading (where the inner surface profile may be straight along the external upset), or a combination of internal and external upsets. Accordingly, drill strings commonly include drill pipe connections having a relatively larger outer diameter when compared with the pipe segment body portions of the drill string between the connections. Additionally, in some cases, drill strings may include other components (e.g., measuring tools, stabilizers, collars, etc.) with different outer diameters.PATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1

[0043] FIG. 2A shows an example of a drill string 298 being moved through the RCD 201, where the drill string 298 has drill pipe connections 295 with larger outer diameters when compared to the pipe segment bodies between the connections 295. According to embodiments of the present disclosure, the sleeve assembly 200 may be designed to ensure a tight seal around a drill string despite drill string outer diameter variation, e.g., caused by pipe connections or other drill string components, by radially constricting the sleeve around the drill string as it is passed therethrough.

[0044] In one or more embodiments, a sleeve assembly may be connected to an inner housing using connection elements that allow axial movement of one or both axial ends of the sleeve assembly in their respective receptacles, which allows the sleeve to “float” a prescribed distance when a drill string is passed through the activated sleeve. For example, connection elements may include a shaft having a connection end connected to an axial end of the sleeve assembly and a spacer portion, where the spacer portion of the shaft may be moved through a connection passage (e.g., a through hole or slot) formed through an inner housing wall. In some embodiments, a connection element may further include a mechanical stop provided at an opposite end of the shaft from the connection end, where the mechanical stop may be sized and / or shaped to prevent axial movement of the sleeve assembly axial end past a selected float distance relative to the inner housing. Accordingly, a sleeve “float” may refer to the axial movement of one or both axial ends of the sleeve assembly relative to the inner housing in which the sleeve assembly is mounted.

[0045] Sleeve “floating” capability may assist with maintaining the seal between the activated sleeve and the drill string as the drill string is axially moved through the RCD. Additionally, sleeve “floating” capability may reduce or prevent tearing in the sleeve that would have otherwise occurred under such high-friction operation of passing a drill string through an activated sleeve. The sleeve “floating” capability may also provide additional strength when the sleeve is statically sealing, allowing for the stresses in the sleeve to be alleviated by the float when the sleeve is activated to seal.

[0046] FIGs. 2A-B, described below, show different examples of RCDs with sleeves having a floating capability according to embodiments of the present disclosure. However, other variations may be envisioned according to embodiments describedPATENT APPLICATIONATTORNEY DOCKET NO. 18954-197W01 herein. Furthermore, in some embodiments, a sleeve assembly may be fitted to a sealing assembly housing (e.g., an inner housing) without a floating capability, such that the sleeve is axially fixed to the sealing assembly housing.

[0047] In the embodiment shown in FIGs. 2A-B, the sleeve assembly 200 includes at least one first connection element 225 connecting the first axial end 205 of the sleeve assembly 200 to the first annular receptacle 212 in the inner housing 203. The first connection element 225 may include a shaft having a mechanical stop 228 at one end, a connection end 226 at the opposite end, and a spacer portion 227 extending between the mechanical stop and the connection end. The spacer portion of the shaft of the connection element 225 may be extended through a connection passage in the first annular receptacle 212 (e.g., through a base wall of the inner housing or along a side wall of the inner housing), where the mechanical stop and connection end may be held on opposite sides of the connection passage. For example, in the embodiment shown in FIG. 2B, the connection end 226 of the first connection element 225 may be connected to (e.g., via a threaded connection), or integrally formed with, the first anchor 210 of the sleeve assembly 200, where the spacer portion 227 of the shaft of the connection element 225 extends from the first anchor 210 through a connection passage formed through abase wall of the inner housing's first annular receptacle 212, and where the connection element’s mechanical stop 228 is positioned on an opposite side of the passage from the first anchor 210. The length of the spacer portion 227 of the shaft (between the connection end 226 and the mechanical stop 228) may be selected to provide a selected axial distance (“float” distance) the connected axial end of a sleeve assembly is able to travel relative to the corresponding connected end of the inner housing.

[0048] The connected first anchor 210 and the mechanical stop 228 may have diameters larger than the passage, such that when the connection element 225 is assembled and connects the sleeve assembly to the annular receptacle, the first anchor 210 and mechanical stop 228 may prevent the connection element 225 from moving out of the connection passage. Additionally, the shaft of the connection element 225 may be longer than the connection passage, which may allow axial movement of the connection element 225 (and thus also axial movement of the connected first axial end 205 of the sleeve assembly) relative to the first annular receptacle 212.PATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1Connection elements, e.g., first connection element 225, may be bolts, pins, or other elongated body that connects to (e.g., via a threaded connection, welding) or is integrally formed with and extends from an anchor of a sleeve assembly. Further, connection elements may be made of the same or different metallic material as the connected anchor, including for example, steel.

[0049] In the embodiment shown in FIGs. 2A-B, the connection ends of the first connection elements 225 are connected to the first anchor 210 of the sleeve assembly 200, while the mechanical stops are positioned on an opposite side of an inner housing wall from the first anchor. However, in other embodiments, a connection element may have its connection end connected to the inner housing and a mechanical stop positioned on an opposite side of a component of the first axial end of the sleeve assembly. In one or more embodiments, a mechanical stop may be a nut that is threaded to a stop end of the shaft opposite the connection end.

[0050] According to embodiments of the present disclosure, multiple connection elements may be circumferentially spaced around and connected to an anchor. Multiple connection elements may be evenly spaced and / or axisymmetrically positioned around the anchor.

[0051] Further, the embodiment in FIGs. 2A-B shows the sleeve assembly 200 connected at a single end of the inner housing 203 in a float configuration using first connection elements 225. However, in one or more embodiments, the sleeve assembly 200 may be connected at both ends with connection elements, including first connection elements 225 at the first axial end 205 and second connection elements at an opposite, second axial end 275 of the sleeve assembly, where the second connection elements may be configured and installed in like manner with the first connection elements 225. By connecting both axial ends of a sleeve assembly using connection elements in float configurations according to embodiments of the present disclosure, the sleeve assembly may have floating capability in a bidirectional axial direction.

[0052] According to embodiments of the present disclosure, an annular seal may be positioned between the axial end of a sleeve assembly and an inner surface of the receptacle in which the axial end of the sleeve assembly is mounted. In some embodiments, the annular seal may be positioned on an anchor or may be integrallyPATENT APPLICATIONATTORNEY DOCKET NO. 18954-197W01 formed with the anchor. Annular seals may be positioned along the inner diameter of an anchor (e.g., first inner annular seal 235) and / or may be positioned along the outer diameter of an anchor (e.g., first outer annular seal 236). Annular seals may include, for example, o-rings. guide rings or wear bands, grooved seals (e.g., buffer or rod seals), and / or wiper seals, the cross-sectional profiles of which are shown in FIG. 2C. For example, a wear band (e.g., made of a polymer or polymer composite such as polytetrafluoroethylene (PTFE) with or without additives or fiber reinforcement) may be positioned between the inner or outer diameter of an anchor and an inner housing receptacle to absorb side load forces and / or prevent metal-to-metal contact that would otherwise damage the components. In some embodiments, a series of annular seals may be provided along the inner and / or outer diameter of an anchor, e.g., to provide seal redundancy.

[0053] In the embodiment shown, a first annular seal 235 may be positioned between an inner side of the first axial end 205 of the sleeve assembly and an inner surface of the first annular receptacle 212. The first annular seal 235 may be positioned within an annular groove formed circumferentially around the inner diameter of the first anchor 210. Additionally, a first outer annular seal 236 may be positioned within an annular groove formed circumferentially around the outer diameter of the first anchor 210. In one or more embodiments, an annular seal is an o-ring. The annular seal may be exposed to fluids from the wellbore at temperatures known at w el I bore conditions.

[0054] The first annular seal 235 may separate the fluid annulus 245 from the drill string 298. Further, the first annular seal 235 may be designed and positioned relative to the first annular receptacle 212 to withstand friction between and maintain the seal between the first anchor 210 and the receptacle when the sleeve assembly is activated (and the axial end is being floated). In such manner, the first annular seal 235 may act as similar to a piston as the first axial end 205 of the sleeve assembly is axially moved within the first annular receptacle 212 during sleeve activation / deactivation, which may lower the sleeve activation pressure needed for activating the sleeve.

[0055] Additionally, one or more second annular seals 265 may be positioned between the second anchor 270 and an inner surface of the second annular receptacle 272. In one or more embodiments, a second annular seal may be positioned in an inner groove formed around a radially inner surface of the second anchor 270 defining the innerPATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1 diameter of the second anchor 270. In some embodiments, a second annular seal may be positioned in an outer groove formed around a radially outer surface of the second anchor 270 defining the outer diameter of the second anchor 270. The second annular seal may be exposed to fluids from the wellbore at temperatures known at wellbore conditions.

[0056] As described with the first annular seal 235, a second annular seal may separate the fluid annulus 245 from the drill string 298. While maintaining the seal, the second annular seal may also reduce the friction between the second axial end 275 of the sleeve assembly and the second annular receptacle 272 as the second axial end 275 moves within the receptacle during sleeve activation / deactivation. which may reduce the sleeve activation pressure from the fluid annulus 245 needed to activate the sleeve.

[0057] By providing annular seals on both axial ends of the sleeve assembly, the sleeve activation chamber (fluid annulus 245) may be sealed from wellbore pressure exposed to the drill string passage.

[0058] FIGs. 3A-B show another example of a sleeve assembly 300 mounted in an RCD inner housing 303 to have “floating” capability according to embodiments of the present disclosure, where one or both of the sleeve assembly axial ends may move axially relative to a corresponding end of the inner housing as the sleeve is activated during operation. FIG. 3 A shows a cross-sectional area of an inactivated sleeve 310 encompassing a drill string 298 in accordance with embodiments of the present disclosure. Inactivated, for purposes of the current disclosure, refers to when a sleeve is not energized by pressure from fluid entering into a fluid annulus 350 around an outer surface of the sleeve. The inactivated sleeve 310, as depicted in FIG. 3 A, may have an initial axial length 320.

[0059] The sleeve assembly 300 in FIGs. 3A-B includes connection elements 360, e.g., such as described in FIGs. 2A-B. connected at both axial ends of the sleeve assembly 300, including first connection elements 360 connected to the first axial end 390 of the sleeve assembly 300 and second connection elements 362 connected to the second (opposite) axial end 392 of the sleeve assembly. Each connection element 360, 362 is connected to an anchor of the sleeve assembly and extends through a connection passage 361 formed through a wall of the inner housing 303 (e.g., a base wall, as shown in FIGs. 3A-B). When the connection elements 360, 362 are connected to thePATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1 sleeve assembly, the shaft of the connection elements 360, 362 may be longer than the connection passage 361 formed through the wall of the inner housing's 303 annular receptacle 380. By using a connection element with a shaft longer than the connection passage through which its connected, the connection element may extend a distance outwardly from the connection passage. Further, the connection passage and the shaft portion of a connection element that extends through the connection passage may be unthreaded (e.g., smooth), such that the unthreaded shaft portion may axially slide through the connection passage. Such configuration may allow axial movement 370 of the connection element 360, 362 (and thus also axial movement of a connected axial end 390, 392 of the sleeve assembly 300) relative to the annular receptacle 380.

[0060] FIG. 3B shows a cross-sectional area of an activated sleeve 330 encompassing a drill string 298 in accordance with embodiments of the present disclosure. Activated, for purposes of the current disclosure, refers to when a sleeve is energized by pressure from fluid (as depicted by the arrow) entering into a fluid annulus 350 around an outer surface of the sleeve, where the sleeve may adapt to the shape of the drill string 298 and the drill pipe connection, ensuring an adequate seal around both the drill string 298 and the drill pipe. The activated sleeve, as depicted in FIG. 3B, may have an activated axial length 340. The activated axial length 340 may be constricted (as depicted by the arrow) as compared to the initial axial length due to the sleeve being energized.

[0061] As shown in FIG. 3B, axial movement 370 of the connection element 360 (and thus also axial movement of a connected axial end 390 of the sleeve assembly 300) relative to the annular receptacle 380 may occur when the sleeve is activated and the activated axial length 340 is constricted.

[0062] FIG. 4A is a partial, close-up view of a cross-sectional area of FIG. 3A of a sleeve assembly 300 where a sleeve 240 is inactivated, according to one or more embodiments. The sleeve assembly 300 may include the sleeve 240 and an inner housing 303. At the axial end of the inner housing 303 may be an annular receptacle 380. An anchor 410 may be positioned in the annular receptacle 380. A connection element 360 may extend from the anchor 410. The connection element 360 may include a mechanical stop 440 and a connection end 450. The mechanical stop 440 may be a stop end opposite the anchor 410. When the sleeve 240 is inactivated, thePATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1 sleeve 240 may have an initial axial length as described with FIG. 3 A. The connection element may be in an initial position 470 when the sleeve 240 is inactivated.

[0063] The mechanical stop 440 may be a physical barrier for the connection element 360. The mechanical stop 440 may have a diameter that prevents the connection element 360 from extending through the base wall of the RCD. In one or more embodiments, the mechanical stop may be a nut that is threaded to the stop end of the connection element, while the connection end of the connection element may be connected to the anchor (e.g., via welding or threaded connection) or integrally formed with and extending from the anchor.

[0064] FIG. 4B is a partial, close-up view of a cross-sectional area of FIG. 3B of the sleeve assembly 300 where the sleeve 240 is activated, according to one or more embodiments. When activated, as discussed with respect to FIG. 3B, the length of the sleeve 240 is constricted due to the sleeve 240 being energized by pressure from fluid entering into a fluid annulus 350 around an outer surface of the sleeve 240. As such, the sleeve 240 may have an activated axial length which is constricted from the initial axial length. In response to the activation of the sleeve 240, a float 490 may occur. The float 490 is an axial sliding that allows for the constriction of the sleeve 240 without straining the elastomer. The float 490 may result in the connection element in a float position 480.

[0065] The connection element 360 may include a shaft with a spacer portion extending a length between the connection end and the mechanical stop 440, where the length of the spacer portion of the shaft and the mechanical stop may be sized and / or shaped to prevent axial movement of the connection element 360 past a selected float distance. For example, the length of the spacer portion of the shaft may be selected to allow the connection element 360 to move axially through the connection passage of the inner housing 303 within a restricted axial distance. With such configuration, the mechanical stop 440 may prevent the connected axial end 390 of the sleeve assembly from moving past a maximum float 490 distance when the sleeve 240 is activated (reducing its axial length). For example, as shown, the restricted axial distance may be selected as an axial distance less than a length 381 of the annular receptacle 380 in which the sleeve’s axial end is being held. In such manner, the axial movement of the sleeve’s axial end is restricted by the connection element’sPATENT APPLICATIONATTORNEY DOCKET NO. 18954-197W01 mechanical stop from coming out of the annular receptacle. This restricted axial movement allows the seal (e.g., provided by annular seal 460) between the fluid annulus around the sleeve and the external environment through the drill string passage to be maintained while at the same time allowing a float of the sleeve assembly during sleeve activation.

[0066] The assembly in FIG. 4B is designed to provide restricted axial movement and float of the sleeve assembly using a connection element 360 capable of sliding through a connection passage 361 formed through the inner housing. In FIG. 4B, the mechanical stop 440 has a diameter larger than the connection passage opening, such that when activation of the sleeve pulls the connection element 360 through the connection passage 361, the mechanical stop 440 abuts an interface surface of the inner housing 303 around the connection passage opening, thereby preventing the connected axial end of the sleeve assembly from coming out of the annular receptacle 380.

[0067] According to embodiments of the present disclosure, other configurations may be used for movably connecting a sleeve assembly axial end to an annular receptacle using a connection element.

[0068] For example, FIGs. 5A-C show another example of a sleeve assembly 500 that is movably connected to an inner housing 502 using connection elements 504 according to embodiments of the present disclosure. In the embodiment shown, the connection elements include a shaft having a connection end at one end connected to a side of an anchor 506 of the sleeve assembly. A spacer portion of the shaft extends outwardly from the connection end, through a connection passage 508 formed through a wall of the inner housing 502. As best seen in FIG. 5C, the connection passage 508 may be a slot extending along an axial length of an inner housing wall. As the sleeve 501 in the sleeve assembly 500 is energized / deenergized, the axial end 503 of the sleeve assembly 500 and connected connection element 504 may axially move relative to the corresponding end of the inner housing 502. The axial movement of the connection element 504 (and thus also the connected axial end 503) is limited in distance by the axial length of the connection passage 508, thereby limiting the axial movement of the sleeve assembly’s axial end 503 to a float distance 510.PATENT APPLICATIONATTORNEY DOCKET NO. 18954-197W01

[0069] FIG. 6 shows another example of a sleeve assembly 600 that is movably connected to an inner housing 602 using connection elements 604 according to embodiments of the present disclosure. In the embodiment shown, the connection element 604 includes a shaft having a connection end 605 at one end connected to a first anchor 606a at the first axial end 603a of the sleeve assembly 600. The shaft extends from the first anchor 606a, through a fluid annulus 612 formed between the sleeve 601 and the inner housing 602, and to a stop end 607. The stop end 607 of the connection element 604 is mounted within a connection passage 608 formed in a second anchor 606b at the second axial end 603b of the sleeve assembly. The connection passage 608 extends an axial distance into the second anchor 606b, and the connection element 604 extends a length from the first anchor 606a into the connection passage 608, where the length of the connection element and the axial distance of the connection passage 608 are selected to allow the stop end 607 of the connection element 604 to move a float distance 610 within the connection passage 608 as the first and / or second axial ends of the sleeve assembly axially move relative to the inner housing during activation / deactivation of the sleeve 601. In such embodiment, the length of the connection element 604 may be selected to extend a length from the connected anchor that is long enough to partially (but not completely) be inserted into the connection passage 608 when the sleeve 601 is deactivated. The axial distance of the connection passage 608 may be selected to prevent axial movement of the connection element's stop end from moving with a connected anchor past the float distance 610. As described above, in one or more embodiments, a float distance may be selected to be less than an axial length of an inner housing receptacle holding a corresponding axial end of the sleeve assembly.

[0070] In another example of embodiments according to the present disclosure, a connection element may be slidably held in a connection passage formed through an axial end of the sleeve assembly or formed through a different component in an inner housing assembly. In such assemblies, the connection element may be fixedly connected (e.g., via threaded connection) at a connection end to either the sleeve assembly or an inner housing assembly, and a mechanical stop (e g., a nut or integrally formed larger end) of the connection element may be provided at an opposite axial end from the connection end. When the connection element is connected in the RCDPATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1 assembly, the connection end and the mechanical stop may be positioned at opposite sides of the connection passage through which the connection element is slid, and are spaced a distance apart from each other that is longer than the connection passage (thereby allowing for the connection element to move the float distance through the connection passage).

[0071] According to embodiments of the present disclosure, the sleeve in a sleeve assembly may include one or more features to improve the life of the sleeve and to improve the performance of the sleeve when activated. For example, FIGs. 7A-7E show various features of a sleeve according to embodiments of the present disclosure, which may be used alone or in combination, to improve the sleeve's life and performance.

[0072] Referring now to FIG. 7 A, FIG. 7 A shows a partial and cross-sectional view of a sleeve assembly 700 according to embodiments of the present disclosure. The sleeve assembly is shown as being axially fixed within an inner housing 203. However, in one or more embodiments, the sleeve assembly may be movably connected to the inner housing to float, as described above.

[0073] In one or more embodiments, the sleeve assembly 700 may include a sleeve 740 having a polymeric sleeve body 760. Examples of suitable materials for the sleeve body 760 include an elastomer. The elastomer may have properties such as high tensile strength, high tear strength, high abrasion resistance, and good performance over a large temperature range. The elastomer may be, for example, polyurethane, nitrile butadiene rubber (NBR), hydrogenated nitrile butadiene rubber (HNBR), or combinations thereof, and may optionally include additives, fillers, or reinforcements. The sleeve body 760 may have a generally cylindrical shape, extending an axial height between a lower surface at the first axial end 705 to an upper surface at the opposite, second axial end 775.

[0074] In one or more embodiments, the sleeve 740 may include a reinforcement member 750 embedded within a polymeric sleeve body 760, such that the reinforcement member 750 is entirely surrounded by the polymeric sleeve body 760. In one or more embodiments, a reinforcement member 750 may have a body that is stiff enough to hold its shape. The reinforcement member 750 may be made of materials that add tensile and / or hoop strength to the sleeve 740. Examples ofPATENT APPLICATIONATTORNEY DOCKET NO. 18954-197W01 materials that add tensile strength may include metallic inserts, rope, fibers or different types of polymers with selected material properties to provide regions of reinforcement in selected local areas of the sleeve. In other embodiments of the present disclosure, the polymeric sleeve body 760 may not include a reinforcement member.

[0075] The polymeric sleeve body 760 may be formed around the reinforcement member 750, e.g., by placing the reinforcement member in a mold, pouring polymeric material forming the sleeve body around the reinforcement member in the mold, and curing the polymeric material around the reinforcement member in the mold. Additionally, in one or more embodiments, reinforcement members may be attached to anchors. For example, a reinforcement member in the form of a bar, strip, or sleeve may be attached at one end to the first anchor and at the opposite end to the second anchor, and the polymeric material forming the sleeve body may be molded around the reinforcement member between the anchors. In other embodiments, reinforcement member(s) may be provided within a sleeve polymeric body without attaching the reinforcement member(s) to the anchors.

[0076] Reinforcement members may strengthen a polymeric sleeve body in an analogous fashion as rebar in concrete providing extra stiffness. Further, reinforcement members may help to keep elastomer strains low while the sleeve is activated during operation.

[0077] In one or more embodiments, a reinforcement member 750 may have a straight axial profile (where the height of the reinforcement member extends linearly). The reinforcement member 750 may be positioned concentrically within the polymeric sleeve body 760 thickness 780, such that the height of the reinforcement member 750 may extend in a direction parallel with the axial length of the sleeve 740. The reinforcement member 750 may extend axially within the polymeric sleeve body 60 at least partially along the axial length of the polymeric sleeve body 760. In the embodiment shown, the reinforcement member 750 extends the axial length of the sleeve 740, from a first axial end 705 to a second end 775 of the polymeric sleeve body 760.

[0078] Additionally. the reinforcement member 750 may extend azimuthally at least partially around the angular distance of the sleeve 740. For example, in one or morePATENT APPLICATIONATTORNEY DOCKET NO. 18954-197W01 embodiments, the reinforcement member 750 may have a cylindrical-shaped body, which may be concentrically positioned within and extend around the entire angular distance of the polymeric sleeve body 760. FIG. 7B shows an example of such configuration more clearly, where FIG. 7B is a cross-sectional view of the RCD sleeve 740 shown in FIG. 7A taken along a plane transverse to the longitudinal axis of the sleeve 740.

[0079] In some embodiments, such as shown in FIG. 7C, a reinforcement member 750 may be formed of multiple segments 752 that each extend partial angular distances around the sleeve, where the multiple segments 752 may be positioned azimuthally around the entire angular distance 705 of the sleeve 740. Reinforcement member segments 752 may be azimuthally spaced apart, e.g., evenly spaced, such as shown in FIG. 7C, or may be abutted next to each other. In some embodiments, such as shown in FIG. 7D, reinforcement members may be ropes 754 that each extend an axial length of the sleeve body 760 (e.g., the entire axial length or a partial axial length).

[0080] Additionally, according to embodiments of the present disclosure, a sleeve may be designed to have a thickened body, where the thickened portion of the body is provided along its interior and / or exterior and extending between the axial ends 705, 775 of the sleeve 740. For example, as best shown in FIG. 7A and 7B, a sleeve 740 has an inner surface 790 and an outer surface 720. where the sleeve thickness 780 is measured radially between the inner and outer surfaces 790, 720. The sleeve 740 may have a varying wall thickness 780 along the axial height of the sleeve 740, which may be formed at least in part by a thickened portion 741 of the body betw een the axial ends 705, 775 of the sleeve. When the sleeve 740 is assembled to an inner housing 703 of an RCD, the first and second axial ends 705. 775 of the sleeve may be connected to first and second anchors 710, 770, respectively, and the thickened portion 741 may be exposed to and partially define the drill string passage through the RCD.

[0081] The thickened portion 741 of the sleeve 740 may be formed by a protruding inner surface of the sleeve, where the protruding inner surface defines an inner diameter of the sleeve that is smaller relative to the remaining portions of the sleeve (e g., smaller than the inner diameter of the sleeve at the sleeve’s axial ends). For example, in the embodiment shown in FIG. 7A, the inner surface 790 of the sleevePATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1740 includes a protruding surface 792, which defines a smallest inner diameter of the sleeve 740, and upper and lower transition surfaces 794, 796, which slope radially outward from the protruding surface 792 to the first and second axial ends 705, 775 of the sleeve 740, respectively. In one or more embodiments, the slopes of the transition surfaces 794, 796 may be designed to correspond with sloping transitions between pipe connections along a drill string. The protruding surface 792 and transition surfaces 794, 796 may extend the entire angular distance of the sleeve. Additionally, in one or more embodiments, the outer surface 720 of the sleeve 740 may have a linear profile extending the axial height of the thickened portion 741 of the sleeve 740, which may define a uniform outer diameter of the sleeve 740 in the thickened portion 741 of the sleeve 740. In some embodiments, a thickened portion of a sleeve may be formed by a protruding outer surface of the sleeve providing a relatively larger outer diameter along a central region of the sleeve compared with the outer diameter along the axial ends of the sleeve. By providing a thickened portion along a central region of the sleeve, the thickened portion may provide resistance to collapse or folding of the sleeve body under external pressure in the fluid annulus 745.

[0082] In one or more embodiments, the protruding surface 792 may extend a majority of the axial height of the sleeve 740. For example, the protruding surface 792 may extend between 60 and 95 percent of the total axial height of the sleeve 740. In such embodiments, the majority of the inner diameter of the sleeve is defined by the protruding surface 792 (defining the smallest inner diameter of the sleeve). The upper and lower transition surfaces 794, 796, which slope radially outward from the protruding surface 792 and define relative larger inner diameters than the protruding surface 792, may in combination extend, for example, between 10 and 30 percent of the total axial height of the sleeve.

[0083] According to embodiments of the present disclosure, a reinforcement member 750 may be positioned radially within the sleeve body 760 at a radial position closer to the outer surface 720 of the sleeve 740 than the protruding inner surface 792 of the sleeve 740. In some embodiments, a reinforcement member may be located at a maximum radial distance from the inner surface of the sleeve while still being encapsulated within the sleeve body 760. In embodiments having multiple reinforcement member segments, each segment may be positioned at substantially thePATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1 same radial distance from the inner surface of the sleeve (e.g., where slight variances may be caused by manufacturing discrepancies). In some embodiments, a reinforcement member 750 within the sleeve 740 including the sleeve body 760 may be mounted to the anchors 710. 770.

[0084] In such configuration, a greater thickness of sleeve body material may be provided on an interior side of the reinforcement member 750 than on an exterior side of the reinforcement member 750. Accordingly, in such manner, the reinforcement member 750 may be located as far as possible from the high strain areas of the polymeric sleeve body located at the sealing interface (contact area) with the drill string, thereby decreasing overall strains in the sleeve and increasing the life of the sleeve.

[0085] For example, during operation of the RCD, the sleeve 740 may be situated around a drill string (e.g., drill string 298 in FIG. 2A) proximate a drill pipe connection (e.g., drill pipe connection 295 in FIG. 2A). The inner surface 790 of the sleeve 740 protrudes away from the reinforcement member 750 towards the drill string, where the protruding surface 792 may provide the largest wall thickness of the sleeve. When the sleeve 740 is energized by pressure from fluid entering into the fluid annulus 745 around the outer surface 720 of the sleeve 740, the sleeve 740 may adapt to the shape of the drill string 298 and the drill pipe connection 295, ensuring an adequate seal around both the drill string 298 and the drill pipe connection 295 point, where the drill string outer diameter increases. The thicker wall thickness of the inner protrusion in the sleeve 740 may reduce the radial distance that the sleeve 740 must deform to fit around the drill string 298. Such reductions in repeated deformation of the sleeve 740 may increase the life of the sleeve 740. Additionally, the thicker wall thickness of the inner protrusion in the sleeve 740 may add sufficient stiffness to the sleeve to allow for the sleeve to fully retract and clear the drill pipe connection in the bore without using an external mechanical retraction mechanism.

[0086] Additionally, by designing the slope of the upper and lower transition surfaces 794, 796 from the inner protrusion to correspond with entry and exit angles to drill pipe connections 295 when the sleeve 740 is deformed under pressure, an adequate seal around the drill string 298 and drill pipe connection 295 may be ensured.

[0087] During constriction of the sleeve to form a seal (e.g., around a drill string or other pipe component), external fluids (e.g., formation fluids from a connected well orPATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1 water from a surrounding subsea environment) may become trapped between the polymeric sleeve and the component being sealed (<?.g., drill string 298). Such trapped fluids may prevent a complete seal of the sleeve against the drill string. In one or more embodiments of the present disclosure, a plurality’ of grooves is present along the interior of the sleeve. These grooves may be filled by trapped fluids as a drill string is moved through the sleeve. In such manner, trapped fluids that would otherwise be moved through the sleeve with the drill string (preventing a complete seal between the drill string and sleeve) may instead be filled into the grooves, thereby allowing the seal of the sleeve against the drill string to be maintained. Further, by trapping formation fluids within the grooves (rather than allowing the fluids to move through the sleeve with the drill string), release of formation fluids from the well side of the RCD to the surrounding environment may be prevented.

[0088] For example, FIGs. 7A and 7E show an example of a sleeve 740 having grooves along its inner surface, where the sleeve may be provided in a sleeve assembly 700 according to one or more embodiments. FIG. 7E shows a cross-sectional view of the sleeve in the sleeve assembly 700 shown in FIG. 7A, taken along a plane transverse to the longitudinal axis of the sleeve assembly 700. The sleeve 740 shown in FIGs. 7A and 7E may be anchored in the sleeve assembly 700 using a floating connection to an inner housing 703, e.g., as described above, or may be fixedly connected to the inner housing 703. Further, while the embodiment shown in FIG. 7A shows the sleeve body as having a reinforcement member 750 provided therein, in one or more embodiments, the sleeve may be formed of a polymeric sleeve body without a reinforcement member (as shown in FIG. 7E).

[0089] In one or more embodiments, e.g., as shown in FIGs. 7A and 7E, the polymeric sleeve body 760 may have a plurality’ of grooves 785 located along the inner surface of the sleeve in a transition region between varying inner diameters of the sleeve. For example, the grooves may be localized to the inner surface 790 proximal to the upper and lower transition surface 794, 796. Thus, the plurality of grooves 785 may be located at the first and second axial end 705, 775 of the sleeve 740. In one or more embodiments, grooves may be positioned in other locations along the sleeve inner surface (in addition to or alternative to the transition region shown in FIG. 7 A) to allow fluids to pass through the sleeve that yvould otherwise be trapped between a passing pipe and the sleeve.PATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1

[0090] Further, the grooves 785 may be circumferentially spaced around the inner surface of the sleeve 740, e.g., in an evenly spaced pattern, or axisymmetric pattern around the inner surface. For example, FIG. 7E shows a cross-sectional view of the sleeve 740 taken along a plane transverse to the longitudinal axis of the sleeve and extending through a transition region in the inner surface of the sleeve w here grooves 785 are formed. In the embodiment shown in FIG. 7E, two grooves 785 are circumferentially spaced around the inner surface 790 of the sleeve 740 in a transition region between the protruding surface 792 and transition surface 794.

[0091] Additionally, as shown in the cross-sectional view of FIG. 7E, the grooves 785 may have a depth 781 that extends partially through the sleeve thickness 780. In one or more embodiments, the depth of a groove, as measured from the inner surface of the sleeve, may vary7along its length. For example, when a groove is formed in a transition region of the sleeve, where the sleeve thickness may vary, the groove may have a relatively shallower depth along relatively thinner portions of the sleeve (e.g., along the transition surfaces) and may have a relatively deeper depth along relatively thicker portions of the sleeve (e.g., along the protruding surface).

[0092] The plurality of grooves 785 may each be rectangular in shape. The size of the grooves may be a balance between being large enough to allow trapped fluid to be released while preventing any abrupt geometry changes from getting caught on the drill string while the sleeve is gripped on the pipe under axial motion through the sleeve.

[0093] FIGs. 8A-B show examples of a sleeve 800 according to embodiments of the present disclosure and grooves 810 formed along an inner surface of the sleeve 800. In the embodiment of FIG. 8A, the inner surface of the sleeve 800 includes a protruding surface 802 defining the smallest inner diameter of the sleeve 800 and transition surfaces 804 extending radially outward from the axial ends of the protruding surface 802, such that the transition surfaces 804 define relatively larger inner diameters of the sleeve. The transition 803 between the protruding surface 802 and each transition surface 804 may be angled or curved. Grooves 810 are formed in the inner surface of the sleeve 800 along the transitions 803 betw een the protruding surface 802 and each transition surface 804. The grooves 810 may have the same or different geometries from each other.PATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1

[0094] In one or more embodiments, the grooves 810 may extend linearly along the inner surface of the sleeve 400 in a direction parallel with the longitudinal axis 805 of the sleeve, such as shown in FIG. 8A. In some embodiments, such as shown in FIG. 8B, grooves 810 may extend linearly (in a direction indicated by groove axis 815) along the inner surface of the sleeve at an angle 807 relative to the longitudinal axis 805, for example, in a helical direction corresponding to the rotational direction of a drill string as it is rotated through the sleeve. Edges of the grooves may be rounded (e.g., formed in a mold with the rounded edges) to ensure no sharp edges catch on the drill string or on any weak points in the polymeric sleeve material. FIG. 8B may be an embodiment of the grooves and sleeve 800 shown in a relaxed position.

[0095] The plurality of grooves 810 may be positioned such that fluids trapped between a drill string and the sleeve 800 as the drill string is moved through the sleeve 800 may be expelled due to a tapered geometry produced by the grooves 810. These trapped fluids may be formation fluids trapped between the sleeve 800 and a drill string as the drill string is being moved out of the sleeve and / or environmental fluids trapped between the sleeve and drill string as the drill string is being moved in through the sleeve. Fluid that is trapped and moved between the sleeve and drill string may lead to a poor seal between the drill pipe and sleeve. By providing grooves along a transition region of the sleeve’s inner surface (where the sleeve’s inner diameter varies), fluid trapped by a drill string may be expelled due to the tapered geometry produced by the grooves. In such manner, the deformation of the sleeve as a pipe moves therethrough is used at the entry or exit transition tapers to push any trapped fluid out (either above or below the sleeve, depending on the direction of travel of the pipe), thereby preventing or inhibiting a “burb” of fluid during passage of the pipe.

[0096] FIGs. 9A-B show a partial cross-sectional view of a sleeve assembly 900 according to embodiments of the present disclosure under pressure from a surrounding exterior fluid annulus and while a drill string 298 is being moved through the interior of the sleeve assembly 900 including a reinforcement member 950. In FIG. 9A, the drill string 298 is being moved in an axial downward direction through the sleeve assembly 900 while pressure around the exterior of the sleeve 940 is constricting the sleeve 940 radially inward to contact and seal against the drill string 298. In FIG. 9B, the drill string 298 is being moved in an opposite, axial upward direction through thePATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1 sleeve assembly 900 while pressure around the exterior of the sleeve 940 is constricting the sleeve 940 radially inward to contact and seal against the drill string 298. During this movement, the potential for trapped fluids 960 may occur.

[0097] In one or more embodiments, while the sleeve 940 is pressurized, a reinforcement member 950 may be deformed to move radially inward with the sleeve 940. For example, the reinforcement member in a sleeve may be manufactured to be straight (having a linear axial profile along the height of the reinforcement member) in a non-deformed state, but may be curved (e.g., as shown in FIGs. 3A-B) when the sleeve is in a deformed state. Manufacturing the reinforcement member to be straight simplifies the manufacturing process, thus reducing manufacturing costs relative to reinforcement members with curvature.

[0098] As shown in FIG. 9A, when the drill string 298 is moved downwardly through the sleeve assembly 900 while the sleeve 940 is pressurized, the inner surface of the sleeve 940 may have a geometry that corresponds with an entry transition 999 to a pipe connection in the drill string 298. As shown in FIG. 9B, when the drill string 298 is moved upwardly through the sleeve assembly 900 while the sleeve 940 is pressurized, the inner surface of the sleeve 940 may have a geometry that corresponds with an exit transition 997 to a pipe connection in the drill string 298.

[0099] Thus, according to embodiments of the present disclosure, when a sleeve is deformed (e.g., due to fluid pressure applied from an outer fluid annulus 245), the inner surface geometry of the sleeve may correspond with a drill string connection outer diameter geometry7when the drill string is moved in both axial directions (into and out of) through the sleeve assembly. This corresponding geometry may provide a consistent seal between the sleeve and a drill string as the drill string is moved through the RCD, thereby ensuring that pressure from the well may be contained in the well (or controlled through w ell fluid control components such as backpressure valves) while the drill string is being moved therethrough. The potential for trapped fluids 960 may impact the ability to provide a consistent seal between the sleeve and a drill string as the drill string is moved through the RCD.

[0100] Embodiments disclosed herein also relate to a method for floating a sleeve during energization and / or movement from application of wellbore pressure across the sleeve. The method may include installing a sleeve assembly with one or morePATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1 connection elements that axially restrict movement of one or both axial ends of the sleeve assembly relative to a corresponding end of an RCD inner housing. The method may include energizing the sleeve and floating the sleeve, where floating may provide a seal of the sleeve onto a drill string.

[0101] In one or more embodiments, the method includes installing a sleeve assembly. The sleeve assembly may include a connection element, where the connection element has a mechanical stop and a connection end. Installing the sleeve assembly may include inserting a first axial end of the sleeve assembly into a first annular receptacle in the inner housing and inserting a second axial end of the sleeve assembly (opposite the first axial end) into a second annular receptacle in the inner housing. One or more annular seals may be provided along an inner surface of the first and / or second axial ends of the sleeve assembly before inserting the axial ends into their respective receptacles, such that when inserted, the annular seal(s) are disposed between the sleeve assembly axial end(s) and an inner surface of the receptacle(s). After inserting the first and second axial ends into their respective annular receptacles, connection elements may be assembled to connect the first and / or second axial end to their respective annular receptacle.

[0102] For example, in some embodiments, after inserting an axial end of a sleeve assembly into an annular receptacle, the connection end of a connection element may be inserted through a passage formed in the annular receptacle and threadedly connected to the axial end of the sleeve assembly, such that a mechanical stop at an opposite end of the connection element remains outside of the annular receptacle. In another example, a connection element may be connected to (or integrally formed with) and extend from an axial end of a sleeve assembly, where the connection element may be inserted through a passage in an annular receptacle when the axial end of a sleeve assembly is inserted into the annular receptacle. After inserting the connection element through the annular receptacle passage, a mechanical stop may be connected to connection element on a side of the connection element outside of the annular receptacle.

[0103] Energizing the sleeve includes filling a fluid annulus to exert external pressure on the sleeve assembly. The fluid annulus is as previously described above. The fluid annulus may be filled with an activation fluid (i.e., a hydraulic fluid). The volume ofPATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1 activation fluid may depend on the geometry of the RCD sleeve and the inner housing. In one or more embodiments, the pressure of the hydraulic fluid in the annulus on the sleeve assembly may be selected based on the wellbore pressure, where an "‘overpressure” may be provided by pressurizing the hydraulic fluid in the annulus to a pressure greater than the surrounding wellbore pressure to successfully close the sleeve and affect a wellbore seal. In some embodiments, the pressure of the hydraulic fluid in the annulus on the sleeve assembly may be a set minimum activation pressure. These activation pressures may vary depending on the sleeve design / geometry, reinforcements, float distance, etc.

[0104] When energized, the sleeve will become activated and constrict in response to the external pressure from the fluid annulus. In response, the sleeve may be floated by the connection element. Floating the sleeve may include axially sliding an axial end the sleeve relative to the inner housing via axial movement of the shaft of the connection element through the connection element passage. The axial sliding may be bidirectional. The amount of axial sliding may be limited by the length of the connection element and the mechanical stop.

[0105] Floating the sleeve may provide a seal of the sleeve onto a drill string. As described above, when the sleeve is energized, the sleeve constricts in response to the external pressure provided by the fluid annulus. Floating the sleeve may allow for the ends of the sleeve to slide in a manner that accommodates the constriction of the sleeve without straining the elastomer. Straining the elastomer may produce an improper seal and degradation of the elastomer. By using embodiments disclosed herein for floating the sleeve, the sleeve may withstand operational friction and pressures without tearing.

[0106] One or more features described herein may be used in combination with one or more other features described herein. For example, one or more of the following features, which are described in more detail above, may be used in combination in a sealing assembly: adjusting fluid pressure in a fluid annulus around a sleeve (e.g., as described with FIGs. 2A-3B); movably mounting the sleeve in a sealing assembly housing to allow the sleeve to move axially a float distance relative to the housing (e g., as described with FIGs. 4A-6); providing the sleeve with an inner surface having transition surfaces sloping radially outward from a protruding surface (e.g., asPATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1 described with FIGs. 7 A and 9A-9B); providing the sleeve with a varying thickness, including a thicker wall portion provided along an inner protruding surface (e.g., as described with FIG. 7 A); one or more reinforcement members embedded within the sleeve (e.g., as described with FIGs. 7B-7D); and grooves formed along an inner surface of the sleeve (e.g., as described with FIGs. 7A and 7D-8B).

[0107] Embodiments of the present disclosure may provide at least one of the following advantages.

[0108] The ability to float the sleeve when the sleeve is energized may lead to an increased lifetime of the sleeve. This may be due to the reduction of strain on the elastomer that the sleeve may include. Reduction of strain occurs due to the abi 1 i ty of the sleeve to float in response to being energized as compared to being stretched.

[0109] An inner diameter protrusion in an RCD sealing element may be provided, which may increase the life of the sleeve in several ways, such as reducing the radial distance a sleeve needs to move to engage a drill pipe and adding stiffness to allow for the sleeve to fully retract and clear the drill pipe connection in the bore without using an external mechanical retraction mechanism. An inner protrusion in a sleeve may also be designed to match drill pipe connection entry and exit angles when the sleeve is deformed with sleeve activation hydraulic pressure to close on the drill pipe. Additionally, an inner protrusion formed in a sleeve may allow reinforcement members to be located as far as possible from the high strain areas of the sleeve located at the sealing interface with the drill pipe, thereby decreasing overall elastomer strains in the sleeve and increasing the life of the sleeve. Providing an inner protrusion in a sleeve may also simplify the manufacturing process by allowing internal supporting reinforcement members to be made with straight, linearly extending height profdes.

[0110] During RCD operation, trapped formation fluids may build up and increase pressure in the RCD. Trapped formation fluids may also prevent the RCD from properly sealing against the drill pipe. By using embodiments disclosed herein, an RCD can expel trapped fluids that may build up and prevent blow-by of fluids into the environment, while still sealing against the drill pipe. The volume passage, such as undesirable blow-by, decreases as the sealing element prevents a build-up of trapped formation fluid during drill-pipe connection. Additionally, the RCD sealing

Claims

PATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1 element feature enables use of RCDs in applications where the system is open to the ocean on one side of the RCD and fluid cannot be expelled to the ocean.[00111] Additionally, embodiments of the pressure disclosure may lower the sleeve activation pressure. Lowering of the sleeve activation pressure may occur based on the use of the annular seal as a piston.[00112] Although only a few example embodiments have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the example embodiments without materially departing from this invention. Accordingly, all such modifications are intended to be included within the scope of this disclosure as defined in the following claims.PATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO1CLAIMSWhat is claimed:

1. A rotating control device (RCD), comprising: an outer housing; an inner housing rotatably mounted within the outer housing, the inner housing comprising a first annular receptacle and a second annular receptacle positioned at opposite sides of the inner housing; a sleeve assembly, comprising: a sleeve; a first anchor at a first axial end of the sleeve, wherein the first anchor is positioned in the first annular receptacle of the inner housing; and a second anchor at a second axial end of the sleeve, wherein the second anchor is positioned in the second annular receptacle of the inner housing; a plurality of connection elements movably connecting the sleeve assembly to the inner housing, wherein each of the plurality of connection elements comprises: a shaft having a connection end connected to the first anchor; and a spacer portion of the shaft extending from the connection end through a connection passage formed through a wall of the inner housing, wherein the plurality of connection elements allows axial movement of the first anchor within the first annular receptacle; and an annular seal positioned between the first anchor and an inner surface of the first annular receptacle.

2. The RCD of claim 1, wherein the connection passage is formed through a base wall of the inner housing.

3. The RCD of claim 1 , wherein the connection end is connected to a side of the first anchor, wherein the connection passage is a slot extending along an axial length of a side wall of the inner housing, and wherein the spacer portion of the shaft extends outwardly from the connection end, through the connection passage,PATENT APPLICATIONATTORNEY DOCKET NO. 18954-197WO14. The RCD of any one of claims 1 -3, wherein the sleeve comprises at least one reinforcement member embedded in a polymeric body.

5. The RCD of claim 4. wherein the at least one reinforcement member comprises ropes extending an axial length along the polymeric body.

6. The RCD of any one of claims 1-3, wherein the sleeve comprises a polymeric body having a varying thickness extending between an inner surface and an outer surface of the sleeve, wherein the inner surface comprises: a protruding surface defining an inner diameter of the sleeve that is smaller relative to remaining portions of the sleeve, wherein the protruding surface forms a thickened portion of the polymeric body; an upper transition surface sloping radially outward from the protruding surface to the second axial end of the sleeve; and a lower transition surface sloping radially outward from the protruding surface to the first axial end of the sleeve.

7. The RCD of claim 6, wherein the upper transition surface and the lower transition surface correspond with transitions between pipe connections along a drill string.

8. The RCD of any one of claims 1-3, wherein the sleeve comprises grooves formed around an inner surface of the sleeve.

9. The RCD of any one of claims 1-3, further comprising a fluid annulus provided around an outer surface of the sleeve, between the sleeve assembly and the outer housing.

10. A sleeve assembly comprising: a sleeve comprising: a polymeric body having a thickness extending between an inner surface and an outer surface of the sleeve, the inner surface comprising: a protruding surface defining an inner diameter of the sleeve that is smaller relative to remaining portions of the sleeve; a lower transition surface sloping radially outward from the protruding surface to a first axial end of the sleeve; andPATENT APPLICATIONATTORNEY DOCKET NO. 18954-197W01 an upper transition surface sloping radially outward from the protruding surface to a second axial end of the sleeve, opposite the first axial end; and a reinforcement member embedded within the polymeric body and extending an axial length along the sleeve; a first anchor connected to the first axial end of the polymeric body; and a second anchor connected to the second axial end of the polymeric body.

11. The sleeve assembly of claim 10, wherein the reinforcement member is a rope.

12. The sleeve assembly of claim 10, wherein the reinforcement member comprises multiple segments each extending a partial angular distance around the sleeve, where the multiple segments are azimuthally spaced around the sleeve.

13. The sleeve assembly of claim 10, wherein the reinforcement member has a straight axial profile, wherein a height of the reinforcement member extends linearly in a direction parallel with an axial length of the sleeve.

14. The sleeve assembly of any one of claims 10-13, wherein the lower transition surface and the upper transition surface protrude the inner surface of the sleeve away from the reinforcement member at an angle corresponding with an angle of a drill pipe connection entry and exit angle.

15. The sleeve assembly of any one of claims 10-13, further comprising a plurality of grooves formed on the lower transition surface or the upper transition surface of the inner surface.

16. A method, comprising; installing a sleeve assembly in an inner housing of a rotating control device (RCD), wherein the sleeve assembly comprises a first anchor connected to a first axial end of a sleeve and a second anchor connected to a second axial end of the sleeve, the installing comprising: inserting a connection element through a connection passage formed through a wall of the inner housing, the connection element comprising a shaft extending from a connection end; and

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