Abstract: The low friction wireline standoff improves wireline cable performance during borehole logging operations. The use of low friction wireline standoffs ameliorates the effects of wireline cable differential sticking, wireline cable key-seating, and high wireline cable drags, by reducing or eliminating contact of the wireline cable with the borehole wall during the logging operation. The low friction wireline standoff comprises external wheels mounted on two finned half shells that clamp onto the wireline with precision cable inserts which are manufactured to fit a wide range of logging cables. The wheels reduce the cable drag down-hole resulting in lower surface logging tensions, aiding conveyance in deep and deviated wells.

Abstract: A stabilizer can include an outer collar, an inner sleeve, and a locking mechanism. The locking mechanism is changeable between a first mode in which the outer collar is rotationally fixed to the inner sleeve and a second mode in which the outer collar is rotationally isolated relative to the inner sleeve. The stabilizer may include an active or passive system for changing modes. An example passive device may include a magnetic clutch where the detected force overcomes magnetic forces to change mode. The stabilizer can be used to mitigate whirl on a rotating device by switching the rotating device between a rotating mode and a non-rotating mode. In the rotating mode, outer collar may rotate with the inner sleeve. In the non-rotating mode, the outer collar may be rotationally isolated from the inner sleeve.

Abstract: An anti-vibration sub for a downhole drill string having a shortened section of steel drill pipe having a reduced diameter body portion with a plurality of axially spaced annular rings and a non-rotating protector sleeve molded to the smaller diameter body portion having an outside diameter that is equal to or greater than the drill string causing the sub to act as a nodal point to absorb vibrational energy from the drill string.

Abstract: A roller reamer for downhole operations in boreholes, such as are drilled for oil and/or natural gas production, or as injection wells. An elongated main body has preferably three circumferentially spaced pockets. A roller assembly is preferably disposed in each pockets, the roller rotating in roller blocks at each end of the roller disposed within the roller blocks. Mating locking profiles, such as dovetails, lock the roller blocks within the pockets, as the roller blocks are moved longitudinally into the locking profiles, preventing any radially outward movement of the roller assembly. The roller assembly is prevented from longitudinal movement within the pockets by lock blocks also positioned within the pockets.

Abstract: A rotary drill bit is operable for forming a wellbore in a geologic formation, and includes a hybrid gauge pad thereon. The hybrid gauge pad includes movable gauge elements biased to protrude radially from a circumferential engagement surface of the gauge pad to define a full gauge of the of the drill bit. The movable gauge elements retract and become flush with the circumferential engagement surface of the gauge pad in response to the application of a steering force to the drill bit, and thus, the circumferential engagement surface of the gauge pad may define the full gauge of the drill bit in a second configuration. The gauge elements are axially spaced from one another and are arranged to provide either uniform engagement forces, or decreasing engagement forces in an axial direction of the drill bit.

Abstract: A rotary steerable tool for directional drilling includes a tool body including a flowbore for flowing pressurized fluid therethrough and a plurality of extendable members movably coupled to the tool body for selectively engaging a borehole wall, each extendable member including a piston for moving the extendable member to an extended position. The tool further includes a pressurized fluid supply flow path to provide fluid pressure from the flowbore to the pistons, and a plurality of linear actuators, each independently actuatable to control fluid pressure from the pressurized fluid supply flow path to a respective piston.

Abstract: A rolling depth of cut controller (DOCC) includes a first retainer including a body portion having an arcuate inner surface. The body portion extends partially around a central axis between the inner surface and an outer surface from a mating surface to an engagement surface. Further, the body portion extends axially along the central axis. The rolling DOCC also includes a second retainer secured to the first retainer at the mating surface via at least one fastening feature. Additionally, the rolling DOCC includes a rolling element disposed at least partially within a cavity formed between the first retainer and the second retainer. The rolling element is configured to rotate within the cavity about the central axis, and an exposed portion of the rolling element is configured to provide depth-of-cut control for a drill bit.

Abstract: A precision linear bearing is designed to minimize the points of contact, rolling and rubbing, to reduce particulates and FOD while ensuring stability and accuracy in a manner suitable for a clean room environment. The linear bearing comprises at least first and second bearing layers within a one-piece housing. Each bearing layer comprises at least three roller bearing spaced around the axial bore in a first plane within the housing, each roller bearing having an axis of rotation substantially perpendicular to the axial bore and projecting into said axial bore for engagement of a linear member extending through the axial bore. Each roller bearing suitably engages the linear member at a single point of contact. The layers are rotationally offset from one another such that the roller bearings contact different positions around the circumference of the linear member. The linear bearing may be configured to engage the inner surface of a cylindrical member.

Abstract: A modified tubular, particularly a drill pipe (12) has a composite non-rotating drill pipe protector assembly (1) including first and second composite collars (2, 3) provided as cooperating parts positionable around the drill pipe (12) and bondable thereto using bonding agent, a non-rotating composite protector shell (4), provided as cooperating shell parts and an internal polymeric radial bearing (7) which fits within a recess (41) within the non-rotating composite protector shell (4) and has an internal surface (10) configured to provide a plurality of internal fluid flow channels (11). An external surface of the non-rotating composite protector shell (4) has blades (14), spaced apart by fluid flow by-pass channels (24). In use the rotation of the drill pipe facilitates fluid movement within the non-rotating composite protector shell by creating a pumping effect inducing ingress of fluid and through-flow within the internal polymeric radial bearing (7).

Abstract: A drilling machine for a wellbore is provided. The drilling machine may include a dynamic lateral pad that is movable between an extended and retracted position. In the extended position, the pad moves the drill bit in a direction for drilling. The drilling machine may include a dynamic lateral cutter that is movable between an extended and retracted position. In at least the extended position, the cutter engages the wellbore and removes formation. The drilling machine may include a monolithic or integral drill bit/drive shaft to reduce the distance between a positive displacement motor and a distal end of the monolithic or integral drill bit/drive shaft. The drilling machine may include separate cutting structures that have different rotational speeds and can further utilize the integral drill bit/drift shaft and/or a bent housing that generates an off-axis rotation which helps optimize the formation removal in the center area of the wellbore.

Abstract: A connection mechanism (4) comprises first and second components (6, 8) which can be selectively coupled together, one of the first or second components comprises a locking member (25) which is moveable between a first state and a second state, the other of the first or second component comprises means (16) for initially moving the locking member from the first to the second state as the first and second components are initially drawn together and means (19) for returning the locking member to the first state once the first and second components are fully engaged together to prevent disengagement of the first and second components.

Abstract: A support assembly and method for supporting an internal assembly in a casing of a turbomachine are provided. The support assembly may include a support member that may be slidably disposed in a recess formed in the internal assembly and configured to engage an inner surface of the casing. A biasing member may be disposed in a pocket extending radially inward from the recess. The biasing member may at least partially extend into the recess and may be configured to apply a biasing force to the support member disposed therein.

Abstract: A stabilizer assembly comprising a tubular member, a stabilizer sleeve slidably disposed about the tubular member, and a plurality of round members each disposed between the stabilizer sleeve and the tubular member. The stabilizer sleeve may comprise a plurality of round cavities each located in an inner surface of the stabilizer sleeve. Each of the plurality of round members may be disposed within a corresponding one of the plurality of round cavities. The stabilizer assembly may be coupled between opposing first and second portions of a downhole drill string.

Abstract: A push-the-bit rotary guiding device includes a mandrel having a central passage, a sleeve rotatably sleeved outside the mandrel, a plurality of swing ribs circumferentially arranged in an outer wall of the sleeve with an interval, an actuation mechanism for controlling each swing rib to swing respectively, a plurality of detectors for detecting a distance to a well wall in real-time, and a controller for determining whether the actuation mechanism is required to actuate the swing ribs to swing according to the detected distance. Through a real-time detection of the detectors of the push-the-bit rotary guiding device, a well section having an expanded or reduced diameter is detected in time and guiding of the rotary guiding device herein is avoided. The rotary guiding device has advantages of a simple and compact structure, convenient machining, easy assembling, and a safe and highly-efficient operation, and is easy to be popularized and applied.

Abstract: An anti-friction device is associated with a drilling element, the drilling element having a substantially cylindrical shape, with a first outside diameter (d1) and a longitudinal extension along a first axis (X). The drilling element includes at least one housing for receiving the anti-friction device. The anti-friction device has a hollow cylindrical shape having an inside diameter (d) which is smaller than the first diameter (d1) of the drilling element and an outside diameter (D) which is greater than the first diameter (d1) of the drilling element. The anti-friction device is adapted to rotate about the first axis (X) in the housing, independently of the drilling element.

Abstract: An apparatus (10) includes a traction member in the form of a roller (24) configured for mounting on a body (12) so as to permit rotation of the roller (24) relative to the body (12). The roller (24) is mountable on the body (12) so as to define a skew angle relative to a longitudinal axis (26) of the body (12). In use, the roller (24) engages a wall of a borehole or bore-lining tubular and the roller (24) urges the apparatus (10) along the wall of the borehole or bore-lining tubular on rotation of the as the roller (24) rotates on the body (12).

Abstract: A buoyancy apparatus operable for connecting to a downhole tool string conveyable within a wellbore extending into a subterranean formation. The buoyancy apparatus comprises a mandrel having an axially extending bore, a first connector disposed at a first end of the mandrel and operable for connecting the buoyancy apparatus to a first portion of the downhole tool string, and a second connector disposed at a second end of the mandrel and operable for connecting the buoyancy apparatus to a second portion of the downhole tool string. A shell extends around the mandrel to define an annular space between the shell and the mandrel. A buoyant material is retained within in the annular space.

Abstract: A technique facilitates drilling of a variety of a wellbores. The technique comprises providing a directional drilling system with a drill bit mounted at the end of a collar having an internal flow passage for drilling fluid. The collar is rotatably positioned in a steering structure to which a plurality of steering members is mounted for lateral motion with respect to the steering structure. The design allows the steering structure to remain rotationally stationary with respect to the surrounding borehole wall as the collar and drill bit are rotated to perform a drilling operation. The drilling orientation of the collar and the drill bit may be adjusted by routing drilling fluid from the internal flow passage to at least one of the steering members to cause lateral displacement of the steering member while the steering structure remains in the rotationally stationary position.

Abstract: An off-axis “cam” drilling tool is provided. The off-axis “cam” drilling tool includes an outer tubing having a throughbore therein, an inner tubing having a throughbore therein, the inner tubing being configured to be inserted within the throughbore of the outer tubing. An annulus is defined between the inner tubing and the throughbore of the outer tubing through which a medium may pass. A cam section can be configured on a portion of the exterior surface of the outer tubing. The outer tubing can be coupled to drill rods of a drill string. The cam section has an axis that is offset to an axis of the outer tubing, and the tool is configured to rotate about cam section axis to lift the drill rods coupled to the outer tubing above a centerline of a drill bore to beneficially orient the drill bit drilling the drill bore.

Abstract: The low friction wireline standoff reduces or eliminates contact of the wireline cable with the borehole wall during the logging operation. The low friction wireline standoff comprises external wheels mounted on two finned half shells that clamp onto the wireline with precision cable inserts.

Abstract: A down hole well tool (1) comprising a tool unit comprising at least one first fluid conduit (2) and a return fluid conduit (3) in use forming a well annulus between the tool unit and a well bore, and at least one piston (4) dividing the well annulus into well annulus spaces. The piston comprises at least two piston bodies wherein a first piston body (4a) is arranged to rotate with the tool unit and a second piston body (4b) is arranged in a position in between the first piston body and the well bore. The first piston body is arranged to rotate relative the second piston body and first sealing means are arranged in between the first piston body and the second piston body.

Abstract: A down hole tool including a compression surface, a compression surface axis, and at least one support member configured to attach the compression surface to a well drilling tool assembly, wherein the extendable support member is extendable by an extension force provided to the support member. The down hole tool is rotable relative to an axis of the well drilling tool assembly, and as the well drilling tool assembly rotates, the at least one compression device exerts a lateral force along a sidewall of a wellbore. Also, a method of forming filter cake comprising releasing a drilling fluid and contacting the drilling fluid with a mechanical pressure on the sidewall of the wellbore and the drilling fluid.

Abstract: The disclosure of this application is directed to a downhole tool comprising a central element/member and a sleeve that is rotatably and orbitally disposed around the central element/member. The sleeve rotates and orbits around the central element/member responsive to fluid flowing through the downhole too. The disclosure is also related to a method of advancing the downhole tool in a well by flowing fluid through the tool.

Abstract: A stabilizer for use in a wellbore string, comprising: an elongate body having an upper end for connection to the wellbore string and a lower end for connection to a wellbore string, a long axis between the ends and an outer surface; and a first cutting ring mounted on the elongate body and exposed on the outer surface with an annular outer surface of the first cutting ring encircling the elongate body.

Abstract: A drill pipe protector assembly comprising at least one protector sleeve (23) adapted to be mounted to the drill pipe string (7) through a fluid bearing (25) so as to be co-axially rotatable with respect to the drill pipe string (7). A retainer arrangement (21, 35) axially fixes the protector sleeve (23) with respect to the drill pipe string (7). The fluid bearing (25) is constructed according to the principles of a hydrostatic fluid bearing. At least one fluid channel (53) connects the fluid bearing (25) to a fluid path of pressurized drilling fluid flowing within an inner space (51) of the drill pipe string (7).

Abstract: An apparatus includes a thrust bearing adapted to engage a tubular component. A bearing carrier is connected to the thrust bearing, an arm is connected to the bearing carrier, and an actuator is connected to the arm. In one embodiment, the bearing carrier includes an arcuate notch through which the tubular component is adapted to extend. In another embodiment, the apparatus has a first configuration in which a vertical offset is defined between the tubular component and the thrust bearing, and a second configuration in which the thrust bearing is engaged with the tubular component for the support thereof. In another embodiment, the apparatus is placed in the first configuration in response to a cessation of a supply of electrical power to a control valve in fluid communication with the actuator. In another embodiment, the tubular component is connected to, or is part of, a quill of a top drive.

Abstract: A drill pipe protector assembly comprising at least one protector sleeve (23) adapted to be mounted to the drill pipe string (7) through a fluid bearing (25) so as to be co-axially rotatable with respect to the drill pipe string (7). A retainer arrangement (21, 35) axially fixes the protector sleeve (23) with respect to the drill pipe string (7). The fluid bearing (25) is constructed according to the principles of a hydrostatic fluid bearing. At least one fluid channel (53) connects the fluid bearing (25) to a fluid path of pressurized drilling fluid flowing within an inner space (51) of the drill pipe string (7).

Abstract: The present invention relates a high-strength nonmagnetic stainless steel, containing, by weight percent, 0.01 to 0.06% of C, 0.10 to 0.50% of Si, 20.5 to 24.5% of Mn, 0.040% or less of P, 0.010% or less of S, 3.1 to 6.0% of Ni, 0.10 to 0.80% of Cu, 20.5 to 24.5% of Cr, 0.10 to 1.50% of Mo, 0.0010 to 0.0050% of B, 0.010% or less of O, 0.65 to 0.90% of N, and the remainder being Fe and inevitable impurities; the steel satisfying the following formulae (1) to (4): [Cr]+3.3×[Mo]+16×[N]?30??(1), {Ni}/{Cr}?0.15??(2), 2.0?[Ni]/[Mo]?30.0??(3), and [C]×1000/[Cr]?2.5??(4), wherein [Cr], [Mo], [N], [Ni], [Mo] and [C] represent the content of Cr, the content of Mo, the content of N, the content of Ni, the content of Mo and the content of C in the steel, respectively, and {Ni} represents the sum of [Ni], [Cu] and [N], and {Cr} represents the sum of [Cr] and [Mo]. The present invention further relates to a high-strength nonmagnetic stainless steel part containing the steel and a process for producing the same.

Abstract: A steerable system comprises a fluid powered motor 10 having a rotor 16 and a stator 18, and a bias arrangement having a plurality of bias pads 34 connected to the stator 18 so as to be rotatable therewith, the bias pads 34 being moveable to allow the application of a side load to the steerable system.

Abstract: A stabilizer and method for use in a wellbore are disclosed. The apparatus can include a rotary body disposed about a tubular and configured to rotate and axially-translate with respect to the tubular. The apparatus can also include a first anti-rotation device disposed axially adjacent the rotary body and configured to resist rotation and axial translation with respect to the tubular. The rotary body can be configured to engage the first anti-rotation device and rotationally lock therewith. The apparatus can also include a biasing member configured to bias apart the rotary body and the first anti-rotation device.

Abstract: A downhole assembly for insertion into a borehole comprising an articulated mandrel, a passive and an active damping mechanism operating on said mandrel for exercising control over torsional stick-slip and further proposing an improvement over the prior art which diminishes lateral shock.

Abstract: An apparatus for use in drilling a high angle or horizontal borehole has a body for coupling to a drill string and one or more traction members mounted for rotation on the body. The apparatus defines a first, passive, configuration and a second, active, configuration in which the traction member urges the apparatus along the inner wall of the borehole.

Abstract: Apparatus and methods operate to seal off a column of effluents standing in a borehole annulus from a drill bit assembly during earth drilling operations. A seal assembly, sections of drill pipe, and tubular casing members are assembled into a fluid pressure-restraining drilling tool. The drilling tool is inserted into a drill string above the drill bit. The seal assembly tracks with the drill string, traveling along the borehole wall to maintain an annular seal at a substantially constant position above the drill bit as drilling operations progress. Pressures produced by the column of effluents are exerted at the upper portion of the seal as the effluent column is prevented from reaching the drill bit.

Abstract: Systems and methods for controlling deviations during drilling operations include securing a plurality of stabilizers to a lower portion of a drill string. The stabilizers can have a substantially triangular cross-sectional area oriented perpendicular to the longitudinal axis of the drill string, and a plurality of blades secured to the stabilizer at points associated with corners of the triangular cross-sectional area. The resulting system can exhibit improved stability and stiffness, an improved flow area, a reduced annular velocity, an increased penetration rate, and a longer usable life.

Abstract: A device (1) for drilling and tamping grounds is constituted by a tamping tip (1A) rigidly connected to a shaft (3) which constitutes the connection to the end part of a battery of rods moved by a drilling machine, which gives it movement in a vertical direction and a rotation around its longitudinal axis. The battery of rods is inserted into a covering tube (14). Between the tamping tip (1A) and the tube (14) a substantially cylindrical tamping element (9, 9a) is interposed, adapted to define a tamping diameter of the ground which forms the walls of the hole obtained by the device (1) at least equal to the diameter of the tube (14).

Abstract: Apparatus, systems, and methods may operate to couple a tubular member to a bottom hole assembly, dispose at least one adjustable stabilizing member on the tubular member, and control at least one of a radial extension of the adjustable stabilizing member and an axial position of the adjustable stabilizing member relative to the bottom hole assembly to adjust a borehole trajectory, wherein the adjustable stabilizing member is adjustable in both radial and axial directions. Additional apparatus, systems, and methods are disclosed.

Abstract: In a downhole motor bearing section having a cylindrical mandrel rotatably disposed within a cylindrical housing, a bi-directional thrust bearing is disposed within a four-shouldered annular containment chamber formed partially into the inner cylindrical wall of the housing and partially into the outer cylindrical wall of the mandrel. Under on-bottom loading conditions, thrust loads are transferred through the thrust bearing by the upper shoulder of the housing and the lower shoulder of the mandrel. The radial widths of these two shoulders are both symmetrical about the centerline of the thrust bearing such that on-bottom thrust loads are transferred non-eccentrically to the thrust bearing, thereby avoiding twisting loads on the thrust bearing races, increasing the effective on-bottom load capacity of the thrust bearing and extending its service life.

Abstract: A tool for use in wellbore drilling that is suitable for use with a drill string for drilling a wellbore having an inner wall. The tool comprises a cylindrical abrasion surface for contacting the inner-wall and generating particles of solid material, and a smearing device coupled with the drill string for applying radial and circumferential force to smear the generated particles onto the inner wall of the wellbore.

Abstract: A subpart of a drill string is described having an outer circumferential surface which is contoured and adapted to engage the wall of the borehole with a small angle of attack while exerting during rotary drilling operations an compacting pressure on mud cake and/or cuttings present in the annulus between the drill string and the borehole.

Abstract: A centralizer for an instrument such as an in-place inclinometer is described. The centralizer has a clamp with an inner receptacle configured for coupling to the instrument housing, and a plurality of elongate fingers extending from the clamp that center the instrument in the casing. The fingers carry rollers that fit into grooves in the instrument casing. The fingers are arcuate and provide a spring-like contact force that causes the rollers to abut the instrument casing and stabilize the instrument.

Abstract: A downhole expandable roller bearing apparatus is described. The apparatus comprises a plurality of roller assemblies comprising at least one roller rotatably mounted between pistons. A retaining member such as a spline bar is removably mounted in a keyway formed in the body. Each piston comprises an aperture through which the spline bar projects in both the inwardly retracted and outwardly deployed positions of the pistons.

Abstract: An expandable downhole tool apparatus is disclosed. The apparatus comprises a body adapted to be incorporated into a drill string and at least one working member moveable relative to the body between an inward deactivated position and an outwardly deployed activated position in order to engage the wall of a borehole. Activation means adapted to move at least one said working member between the inward deactivated position and outwardly deployed activated position is provided. At least one passage is formed through the body and extends from a location on the body adjacent at least one working member to a location remote from the respective working member to enable debris accumulating underneath the respective working member to move along the passage and exit the body.

Abstract: Systems and methods for controlling deviations during drilling operations include securing a plurality of stabilizers to a lower portion of a drill string. The stabilizers can have a substantially triangular cross-sectional area oriented perpendicular to the longitudinal axis of the drill string, and a plurality of blades secured to the stabilizer at points associated with corners of the triangular cross-sectional area. The resulting system can exhibit improved stability and stiffness, an improved flow area, a reduced annular velocity, an increased penetration rate, and a longer usable life.

Abstract: A method and apparatus for stabilizing a downhole tool during a downhole operation. The method and apparatus include a stabilizer having a stabilization member adapted to move between a retracted position and an extended position in order to engage a surface in a wellbore. The stabilizer also includes a plurality of actuators adapted to move the stabilization members from the retracted position to the extended position.

Abstract: Systems for controlling deviations during drilling operations, including a transmission housing and a bearing assembly secured between a stator housing and a drill bit. Two stabilizers are secured to the transmission housing, and one stabilizer is secured to the bearing assembly to provide enhanced stability to the lower portion of the drill string. The stabilizers can have a triangular shaped body for increasing flow area, reducing annular velocity, and increasing stiffness of the system. The stabilizers can be rotationally offset from one another to facilitate maintaining the gauge of the borehole. The transmission housing can be a one-piece construction to minimize connections within the system and improve reliability. The stabilizers can include laser clad metal surfaces and diamond dome inserts to prevent wear and erosion. A triangular reamer can be included beneath the stabilizers to further prevent wear to the stabilizers and to add stability to the drill bit.

Abstract: This invention relates to a downhole assembly and to a cutter assembly, and in particular to a downhole assembly including an apparatus for breaking up large-scale material which is present behind a drill bit, and to a cutter assembly for use in such a downhole assembly. The downhole assembly is suitably for use in a drillstring, the downhole assembly comprising a drill bit, a sensitive component, and at least one rotatable set of cutter blades located between the drill bit and the sensitive component.

Abstract: A transport assembly configured to be attached to downhole apparatus has a support assembly configured to be attached to the downhole apparatus and a ground engaging assembly, which may be a roller wheel configured to contact with and move in relation to a surface of a wellbore. The roller wheel may engage with the support assembly so as to provide for their relative rotation. The transport assembly also includes a retaining member disposed between the roller wheel and the support assembly, and the retaining member is operable to resist separation of the roller wheel from the support assembly. The transport assembly is further configured such that, when the transport assembly is in use moving along a wellbore, the roller wheel bears against the retaining member, which in turn bears against the support assembly. The retaining member is a ball-bearing.

Abstract: An electrically powered and controlled tractor system includes one or more electric gripper assemblies and one or more electric power train assemblies. Power and control signals for the gripper assemblies and power train assemblies can be delivered from a ground surface via a wireline. The gripper assembly employs a motor-activated lead screw and nut combination to expand passage-gripping elements, preferably by pushing the gripping elements radially outward from locations between opposing ends of the gripping elements. A failsafe mechanism can retract the gripping elements during a power interruption. The power train assembly employs a motor-activated lead screw and nut combination to expand and contract two or more telescoping members. The tractor system can include multiple tractor units that each includes one gripper assembly and one power train assembly. A tractor can include one power train assembly and two gripper assemblies.

Abstract: A system and method is provided for a low profile rotating control device (LP-RCD) and its housing mounted on or integral with an annular blowout preventer seal, casing, or other housing. The LP-RCD and LP-RCD housing can fit within a limited space available on drilling rigs. An embodiment allows a LP-RCD to be removably disposed with a LP-RCD housing by rotating a bearing assembly rotating plate. A sealing element may be removably disposed with the LP-RCD bearing assembly by rotating a seal retainer ring. Alternatively, a sealing element may be removably disposed with the LP-RCD bearing assembly with a seal support member threadedly attached with the LP-RCD bearing assembly. The seal support member may be locked in position with a seal locking ring removably attached with threads with the LP-RCD bearing assembly over the seal support member. Spaced apart accumulators may be disposed radially outward of the bearings in the bearing assembly to provide self lubrication to the bearings.

Abstract: The invention relates to a downhole device for incorporation into a downhole string and movement in a wellbore. The device comprises a body member, at least one roller arranged on the device to engage the inner surface of the wellbore and means to orient the device in the wellbore. The means to orient the device are provided on the or each roller. Preferably the means to orient the device comprise a projecting portion provided on the or each roller which projects radially outwardly from the body member. The projecting portion can be an eccentrically-shaped portion of the or each roller.