During drilling operations, drilling mud may be pumped into a wellbore. The drilling mud may serve several purposes, including applying a pressure on the formation, which may reduce or prevent formation fluids from entering the wellbore during drilling. The formation fluids mixed with the drilling fluid can reach the surface, resulting in a risk of fire or explosion if hydrocarbons (liquid or gas) are contained in the formation fluid. To control this risk, pressure control devices are installed at the surface of a drilling, such as one or more blowout preventers (BOPs) that can be attached onto a wellhead above the wellbore. A rotating control device (RCD) is typically attached on the top of the BOPs to divert mud/fluid, and circulate it through a choke manifold to avoid the influx of fluid reaching a drilling rig floor (as well as allowing pressure management inside the wellbore). A bearing assembly is used for purposes of controlling the pressure of fluid flow to the surface while drilling operations are conducted. The bearing assembly is typically raised by a top drive assembly and then inserted into a “bowl” of a housing of the RCD. The bearing assembly rotatably receives and seals a drill pipe during drilling operations through the wellhead. Thus, the bearing assembly acts as a seal and a bearing, as supported by the RCD housing.
After the bearing assembly is inserted into the bowl of the housing of the RCD, the RCD can be operated to “lock” a stationary housing of the bearing assembly to the RCD housing (while still allowing for the rotational components of the bearing assembly to rotate along with a rotating drill pipe). This “locking” function is typically performed with ram mechanisms coupled to the RCD housing and that are actuated to lock the bearing assembly to the RCD housing, and then actuated to unlock the bearing assembly from the RCD housing (such as when seals of the bearing assembly need to be replaced). Another type of locking mechanisms includes a clamp mechanism that is manually or hydraulically actuated to lock the bearing assembly to the RCD housing. The ram mechanism must have internal machine thread and threaded rod, and a motor to rotate the threaded rod. The rod drives the ram into the bearing assembly to lock it. This is disadvantageous because the ram mechanism must be locked manually by an operator, which is dangerous and time consuming.
Features and advantages of the invention will be apparent from the detailed description which follows, taken in conjunction with the accompanying drawings, which together illustrate, by way of example, features of the invention; and, wherein;
Reference will now be made to the exemplary embodiments illustrated, and specific language will be used herein to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended.
As used herein, the term “substantially” refers to the complete or nearly complete extent or degree of an action, characteristic, property, state, structure, item, or result. For example, an object that is “substantially” enclosed would mean that the object is either completely enclosed or nearly completely enclosed. The exact allowable degree of deviation from absolute completeness may in some cases depend on the specific context. However, generally speaking the nearness of completion will be so as to have the same overall result as if absolute and total completion were obtained. The use of “substantially” is equally applicable when used in a negative connotation to refer to the complete or near complete lack of an action, characteristic, property, state, structure, item, or result.
As used herein, “adjacent” refers to the proximity of two structures or elements. Particularly, elements that are identified as being “adjacent” may be either abutting or connected. Such elements may also be near or close to each other without necessarily contacting each other. The exact degree of proximity may in some cases depend on the specific context.
An initial overview of the inventive concepts are provided below and then specific examples are described in further detail later. This initial summary is intended to aid readers in understanding the examples more quickly, but is not intended to identify key features or essential features of the examples, nor is it intended to limit the scope of the claimed subject matter.
The present disclosure sets forth a rotating control device (RCD) for a drilling operation comprising a housing operable with a blowout preventer, and a bearing assembly operable to be received in the housing, and operable to receive a pipe of a drill string. The RCD can comprise a plurality of locking pin assemblies supported by the housing. Each locking pin assembly can comprise a movable pin operable between a locked position that locks the bearing assembly to the housing, and an unlocked position that unlocks the bearing assembly from the housing.
In some examples, each movable pin comprises a bearing interface surface configured to interface with a perimeter channel of a lower sealing element sleeve of the bearing assembly.
In some examples, each movable pin comprises a recessed portion, and upon moving each movable pin to the unlocked position, the recessed portion is spatially separated from the lower sealing element sleeve to facilitate removal of the bearing assembly from the housing.
In some examples, each locking pin assembly comprises at least one elastic component situated between the movable pin and the housing. The at least one elastic component can be configured to automatically bias the movable pin in the locked position.
The present disclosure further sets forth another exemplary RCD for use on a drill rig. The RCD can comprise an RCD housing coupled to a blowout preventer; a bearing assembly received within the RCD housing and comprising a lower sealing element sleeve having a perimeter channel; and a plurality of locking pin assemblies supported by the RCD housing and operable between a locked position and an unlocked position. Each locking pin assembly can comprise a movable pin operable to engage the perimeter channel of the bearing assembly to lock the bearing assembly to the RCD housing.
In some examples, each movable pin comprises a bearing assembly interface surface configured to interface with the perimeter channel of the lower sealing element sleeve, and each movable pin can be rotatable or translatable when actuated between the locked position and the unlocked position.
The present disclosure further sets forth a system for facilitating replacement of one or more sealing elements (e.g., packers) associated with an RCD. The system can comprise an RCD comprising a RCD housing coupled to a blowout preventer, and the RCD can comprise a bearing assembly received within the RCD housing and configured to receive a pipe of a drill string of the oil rig. The bearing assembly can comprise a lower sealing element sleeve; a lower sealing element coupled to the lower sealing element sleeve; a lower sealing element housing coupled to an upper sealing element sleeve; and an upper sealing element coupled to the upper sealing element sleeve. The system can comprise a plurality of lower locking pin assemblies supported by the RCD housing, and that are operable between a locked position and an unlocked position. When in the locked position, the plurality of lower locking pin assemblies lock the lower sealing element sleeve to the RCD housing, and when in the unlocked position, the bearing assembly unlocks the lower sealing element sleeve from the RCD housing to facilitate replacement of the lower sealing element. The system can comprise a plurality of upper locking pin assemblies supported by an upper sealing element housing and operable between a locked position and an unlocked position. When in the locked position, the plurality of upper locking pin assemblies lock the upper sealing element sleeve to the upper sealing element housing, and when in the unlocked position, the plurality of upper locking pin assemblies unlock the upper sealing element sleeve from the upper sealing element housing to facilitate replacement of the upper sealing element.
The present disclosure still further sets forth a method for operating an RCD for a drilling operation. The method can comprise identifying an RCD coupled to a blowout preventer of a drill rig. The RCD can comprise an RCD housing operable with the blowout preventer, and a bearing assembly receivable into the RCD housing and operable to receive a pipe of a drill string. The RCD can comprise a plurality of locking pin assemblies supported by the RCD housing, and each locking pin assembly can have a movable pin. The method can comprise applying an actuation force to the movable pins of the plurality of locking pin assemblies to be in an unlocked position. Each moveable pin is caused to be displaced in a direction so as to compress the respective at least one elastic component. The method can comprise inserting the bearing assembly into the RCD housing, and facilitating moving the movable pins from the unlocked position to a locked position, wherein the moveable pins interface with and engage the bearing assembly.
In some examples, the method comprises removing fluid pressure from fluid pressure chambers of the housing to cause each movable pin to automatically move to the locked position via a biasing force (e.g., a spring force, or a force exerted by a spring or other similar component) exerted on the movable pins via respective elastic components coupled to each movable pin.
To further describe the present technology, examples are now provided with reference to the figures.
With reference to
The housing 110 can comprise sub-housings 118a and 118b that each support respective lower locking pin assemblies as part of a locking block system for the RCD 100 (see lower locking pin assemblies 120a, 120b in
The bearing assembly 102 can comprise a lower sealing element sleeve 122 that rotatably supports a lower sealing element sleeve 124 via upper and lower bearing assemblies 126a and 126b. The upper and lower bearing assemblies 126a and 126b can be situated between the lower sealing element sleeve 124 and the lower sealing element sleeve 122 to rotatably support the lower sealing element sleeve 124 about the lower sealing element sleeve 122. In one example, as shown, the bearing assemblies 126a and 126b can comprise tapered bearings. It is noted that those skilled in the art will recognize that other types of bearing assemblies could be used, and incorporated between the lower sealing element sleeve 122 and the lower sealing element sleeve 124. As such, the tapered bearings shown are not intended to be limiting in any way.
A lower sealing assembly 128 can be attached to a lower end of the rotary casing 124 via fasteners 130. The lower sealing assembly 128 can comprise a lower plate lock device 132 and a lower sealing element 134 (e.g., a rubber stripper/packer) removably coupled to the lower plate lock device 132. One example configuration of the lower sealing assembly 128 is further described in U.S. patent application Ser. No. ______ filed ______ (Attorney docket No. 3749-014), which is incorporated by reference herein in its entirety. Those skilled in the art will recognize other ways for coupling the lower sealing element 134 to or about the bearing assembly 102.
The lower sealing element 134 can comprise an opening 136 sized to receive the pipe 108 (
In one example, as shown, the upper sealing assembly 109a can comprise a upper sealing element housing 138 coupled to an upper end of the lower sealing element sleeve 124 via fasteners 140. The upper sealing element housing 138 defines a bowl area 142 and supports a plurality of upper locking pin assemblies 120a′ and 120b′ operable to lock and unlock an upper sealing element sleeve 146, via a perimeter channel 256 of the upper sealing element sleeve 146, as further detailed below. Note that the upper sealing assembly 109a is an optional assembly that can be coupled to the lower bearing assembly 109b; however, only the lower bearing assembly 109b may be utilized in some applications as desired. An upper sealing assembly 148 can be coupled to a lower end of the upper sealing element sleeve 146 via fasteners 149. The upper sealing assembly 148 can comprise an upper plate lock device 150 and an upper sealing element 152 (e.g., a rubber stripper/packer) removably coupled to the upper plate lock device 150. The configuration of the upper sealing assembly 148 is further described in U.S. patent application Ser. No. ______ filed ______ (Attorney docket No. 3749-014), which is incorporated by reference herein in its entirety. The upper sealing element 152 can comprise an opening 154 sized and configured to receive the drill pipe 108 (
When the upper and lower sealing elements 152 and 134 wear down and need to be replaced (e.g., sometimes daily), the bearing assembly 102 can be removed from the RCD housing 110 when the lower locking pin assemblies (e.g., lower locking block assemblies 120a and 120b) are in the unlocked position (discussed below). Once the bearing assembly 102 is removed, the lower sealing element 134 can be removed (via the lower plate lock device 128) and replaced with a new sealing element. Similarly, the upper sealing element sleeve 146 (and the attached upper sealing element 152) can be removed from the upper sealing element housing 138 upon moving the upper locking pin assemblies 120a′ and 120b′ to the unlocked position, and the upper sealing element 152 replaced with a new sealing element.
With reference to
More specifically, and in one example, the lower sealing element sleeve 122 can comprise a perimeter or circumferential groove or channel 156 formed as an annular recess around the cylindrically-shaped, lower sealing element sleeve 122 (see e.g.,
The movable pins 162a and 162b can comprise respective bearing interface surfaces 164a and 164b configured to interface with the perimeter channel 156 of the lower sealing element sleeve 122 when moved to the locked position. The bearing interface surfaces 164a and 164b can be curved or radial perimeter surfaces having a shape and size corresponding to the shape and size of the perimeter channel 156. This can maximize the surface-to-surface contact between the movable pins 162a and 162b, and the lower sealing element sleeve 122, to maximize a locking force that resists upward pressure from mud/fluid from below the bearing assembly 102. The movable pins 162a and 162b can comprise respective recessed portions 166a and 166b formed about a central area of the respective movable pin 162a and 162b, as further detailed below.
The movable pins 162a and 162b can each comprise respective actuation members 168a and 168b that extend from ends of the movable pins 162a and 162b. The actuation members 168a and 168b can be formed as part of the movable pins 162a and 162b, or coupled thereto in a suitable manner. In one example, respective actuation devices 170a and 170b (schematically shown) can be supported by or coupled to the respective sub-housings 118a and 118b. The actuation devices 170a and 170b can be hydraulic rotary actuators configured to rotate the respective movable pins 162a and 162b (via the actuation members 168a and 168b) clockwise and/or counter-clockwise about respective axes of rotation X1 and X2. In another example, the actuation members 168a and 168b can instead be actuation rods that extend into a portion of respective movable pins 162a and 162b, and secured thereto by suitable means, such that rotation of the actuation rods causes rotation of the movable pins 162a and 162b between the locked and unlocked positions.
Regardless of the means of rotating the movable pins 162a and 162b, in one example an actuation system, such as a hydraulic actuation system 172 (schematically shown), can be operably coupled to the actuation devices 170a and 170b. The actuation devices 170a and 170b can be part of the hydraulic actuation system 172. The hydraulic actuation system 172 can be configured to supply and remove fluid pressure to each actuation device 170a and 170b to cause rotation/actuation of the movable pins 162a and 162b, as described herein. The hydraulic system 172 can comprise a number of hydraulic valves, pumps, motors, controllers, etc., known in the art to supply and remove fluid pressure to a hydraulic actuation device to cause rotation of a member (e.g., movable pins 162a and 162b). The hydraulic system 172 can be operated manually or automatically by a computer system operable to control the hydraulic system 172 by known means of controlling hydraulic pumps and motors, such as control panels, switches, etc. In other examples, the movable pins 162a and 162b can be actuated by an electric actuator, pneumatic actuator, a screw or screw-type actuator, a manual actuator, and other such suitable actuators operable to rotate the movable pins 162a and 162b, as will be recognized by those skilled in the art.
In the example shown, each axis of rotation X1 and X2 can be generally parallel to each other because the movable pins 162a and 162b are situated generally parallel to each other as disposed on either side of the lower sealing element sleeve 122. However, the movable pins 162a and 162b can be situated at other angles relative to each other, and even three or more movable pins can be disposed around the housing 110 in a surrounding manner, and operated in a similar manner as those shown.
In some examples, each axis of rotation X1 and X2 is generally perpendicular to an axis of rotation Y of the bearing assembly 102 (
As best shown in
In one example, the recessed portions 166a and 166b can each be defined by a partial-cylindrical shaped void area formed through a portion (e.g., a central area) of the movable pins 162a and 162b. Thus, the recessed portions 166a and 166b can have respective planar surfaces 174a and 174b that can extend generally vertical, relative to the axis of rotation Y of the bearing assembly 102, when in the locked and unlocked positions. Said another way, when in the unlocked position illustrated in
Upon moving from the locked position (
With reference to
Similarly as described above with reference to
The movable pins 262a and 262b can comprise respective first and second bearing interface surfaces 264a and 264b each configured to interface with a portion of the perimeter channel 156 on either lateral side of the lower sealing element sleeve 122 when in the locked position. The first and second radial interface surfaces 264a and 264b can be curved or circular-shaped surfaces having a shape and size corresponding to the shape and size of the perimeter channel 156. This can maximize the surface-to-surface contact between the movable pins 262a and 262b, and the lower sealing element sleeve 122, to maximize a locking force that resists upward pressure from mud/fluid from below the bearing assembly 102. The movable pins 262a and 262b can comprise respective recessed portions 266a and 266b formed about a portion (e.g., a central area) of the respective movable pins 262a and 262b. The recessed portions 266a and 266b can each be formed having a curved recessed surface 274a and 274b having a horizontal profile corresponding to the shape of the perimeter channel 156 of the lower sealing element sleeve 122. In this manner, when in the unlocked position, the recessed portions 266a and 266b are spatially separated from the perimeter channel 156 to facilitate unlocking the bearing assembly 102 from the housing 110, as shown on
The movable pins 262a and 262b can comprise respective first and second outer housing interface surfaces 267a and 267b, each having outwardly circular surfaces formed along outer surface portions of the respective movable pins 262a and 262b. The first and second outer housing interface surfaces 267a and 267b are formed opposite respective first and second bearing interface surfaces 264a and 246b. The first and second outer housing interface surfaces 267a and 267b can be slidably interfaced to corresponding inner radial walls 280a and 280b of the respective sub-housings 218a and 218b. The first and second bearing interface surfaces 264a and 264b of the movable pins 262a and 262b can be slidably interfaced to corresponding inner radial walls 283a and 283b of the respective sub-housings 218a and 218b. Note that first and second bearing interface surfaces 264a and 264b can be formed along the same side, and adjacent, the respective recessed portions 266a and 266b.
The movable pins 262a and 262b can further comprise respective upper and lower housing interface surfaces 265a-d (
As shown in
In one aspect, a fluid (hydraulic or pneumatic) system 272 (schematically shown) can be operably coupled to respective sub-housing 218a and 218b via fluid lines coupled to respective fluid ports 270a and 270b of the sub-housing 218a and 218b. The fluid ports 270a and 270b can have connectors or valves coupled to the respective sub-housing 218a and 218b adjacent ends of respective moveable pins 262a and 262b. The sub-housings 218a and 218b can each comprise a fluid pressure chamber 273a and 273b (
More specifically, when the movable pins 262a and 262b are in the locked position due to spring forces exerted by the respective elastic components 284a and 284b, fluid pressure is not supplied (or is nonexistent) to the fluid pressure chambers 273a and 273b. Upon supplying fluid pressure to the fluid pressure chambers 273a and 273b via the fluid ports 270a and 270b, an amount of actuation force due to the supplied fluid pressure becomes greater than the spring or biasing forces exerted against the movable pins 262a and 262b. In this manner, the fluid pressure supplied to the fluid pressure chambers 273a and 273b exerts a force that axially translates the movable pins 262a and 262b along respective axes of translation X3 and X4, and to the unlocked position. Accordingly, such fluid pressure overcomes the forces exerted by the elastic components 284a and 284b and causes compression of the elastic components 284a and 284b, thereby actively actuating the movable pins 262a and 262b in the unlocked position of
In this unlocked position, the recessed portions 266a and 266b have been moved to positions, such that the respective curved interface surfaces 274a and 274b are spatially separated from the perimeter channel 156 of the lower sealing element sleeve 122. In this manner, the bearing assembly 102 is unlocked from the housing 110 so that it can be removed therefrom.
The fluid system 272 can comprise a number of hydraulic (or pneumatic) valves, pumps, motors, controllers, etc., known in the art to supply and remove fluid pressure about the fluid pressure chambers, and can be operated manually or automatically by a computer system operable to control the hydraulic system 272 by known means of controlling hydraulic pumps and motors. In other examples, the movable pins 262a and 262b can be actuated pneumatically by supplying compressed gas to the fluid pressure chambers 273a and 273b with sufficient gas pressure to overcome the applied spring forces. Such gas pressure can be removed so that the elastic components 284a and 284b can automatically bias the respective movable pins 262a and 262b in the locked position.
No matter the type of actuation system utilized, the movable pins 262a and 262b can “automatically” transition from the unlocked position (
However, with the present technology disclosed herein, the expanding elastic components 284a and 284b, and the curve shape of the first and second bearing interface surfaces 264a and 264b tend to compensate for such possible misalignment when allowing the movable pins 262a and 262b to automatically move to the locked position. For example, if for some reason the movable pin 262a initially contacts the stationary bearing assembly 122 before the other movable pin 262b contacts the stationary bearing assembly 122, and if the bearing assembly 102 is vertically and/or laterally misaligned to the housing 110, the outward curvature of the first bearing interface surface 264a will slide along and self-align with the corresponding curvature of the perimeter channel 156 until the movable pin 262a is fully in the locked position. Such slidable interfacing can vertically and/or laterally properly position the lower sealing element sleeve 122 until such time that the other movable pin 262b contacts and interfaces with the perimeter channel 156 on the other side of the lower sealing element sleeve 122, which itself has a slidable interface and which can also self-align. Thus, the system can self-align the bearing assembly 102 to the housing 110 despite the speed and/or position of either movable pin 262a or 262b relative to the other.
The self-alignment features described above regarding
As can be appreciated, for example with reference to
The movable pin assemblies of the examples of
Alternatively, the (rotatable) upper movable pins 162a′ and 162b′ of the upper locking pin assemblies 120a′ and 120b′ can be replaced with the configuration and function of the (translatable) movable pins 262a and 262b, as described regarding
Reference was made to the examples illustrated in the drawings and specific language was used herein to describe the same. It will nevertheless be understood that no limitation of the scope of the technology is thereby intended. Alterations and further modifications of the features illustrated herein and additional applications of the examples as illustrated herein are to be considered within the scope of the description.
Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more examples. In the preceding description, numerous specific details were provided, such as examples of various configurations to provide a thorough understanding of examples of the described technology. It will be recognized, however, that the technology may be practiced without one or more of the specific details, or with other methods, components, devices, etc. In other instances, well-known structures or operations are not shown or described in detail to avoid obscuring aspects of the technology.
Although the subject matter has been described in language specific to structural features and/or operations, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features and operations described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims. Numerous modifications and alternative arrangements may be devised without departing from the spirit and scope of the described technology.