Abstract: A method for drilling a subterranean wellbore includes rotating a drill string in the subterranean wellbore to drill the wellbore. The drill string includes a rotary steerable tool or a steerable drill bit including at least first and second axially spaced pads configured to extend radially outward from a tool body and engage a wall of the wellbore. Radial displacements of each of the first and second axially spaced pads are measured while drilling. The measured radial displacements are processed to compute a rate of penetration of drilling.

Abstract: A section mill for milling wellbore tubulars has a tubular mill body, a pivotally mounted mill carrier having a beveled interior profile and a cutter blade on its exterior profile, and a translatable piston having an elongated driveshaft with a radially extending nose cone with a compression spring positioned around the elongated driveshaft. A hook on the elongated driveshaft configured to mate with a corresponding hook catch in the mill carriers maintains the mill carrier in a retracted position. The nose cone of the translatable piston moves upward and downward along the beveled interior profile of the mill carrier in response to fluid pressure. Rotation of the mill body rotates the attached mill carrier and cutter blade for milling.

Abstract: The present disclosure relates to an underreamer. In one aspect, the underreamer comprises a body, the body comprising at least one pocket therein, the underreamer further comprising at least one cutter secured with respect to the body, at least one actuating mechanism for moving the cutter between a retracted position in the pocket, and an extended position in which only the cutter projects from the body. In one aspect, the or each actuating mechanism comprises a piston for driving extension of the cutter, and a linkage to a cutter arm with respect to which the cutter is mounted, and a return spring for biasing the cutter to the retracted position.

Abstract: A self-powered sensor array (SPSA) for sensing environmental parameters along a drillstring includes an outer collar having moveable member retainers with moveable members movably located in the moveable member retainers. An inner ring is rotatably supported within the outer collar with bearing elements on an outer surface of the inner ring positioned to displace the moveable members relative to the moveable member retainers in response to relative rotation between the inner ring and the outer collar. Shape memory material elements are arranged in a respective moveable member retainer. Distance sensors are configured to sense a gap responsive to a shape change of the respective shape memory material element and a displacement of the respective moveable member. Power generation components are configured such that, in response to the relative rotation, the bearing elements displace a particular moveable member into a particular moveable member retainer, generating an electric charge.

Abstract: A drill bit for drilling a bore, the drill bit comprising: an outer housing; a primary cutting structure defining a cutting plane of a first diameter; a flow path arranged to let drilling fluid flow through the drill bit; and a deployable blade assembly at least partially located within the outer housing, the deployable blade assembly comprising a cutting structure and being arranged to be axially movable from a first position, in which the deployable cutting structure is recessed with respect to the primary cutting structure, towards the cutting plane, to a second position; wherein when the deployable blade assembly is in the second position, the deployable cutting structure defines a cutting diameter which is less than or equal to the first diameter.

Abstract: The invention discloses an anti-rotating device of non-rotating sleeve. The anti-rotating device is connected with the non-rotating sleeve in such way so that the anti-rotating device can transmit circumferential acting force to the non-rotating sleeve, thus the non-rotating sleeve are prevented from rotating, the anti-rotating device comprises an anti-rotating member and a resilient member, the anti-rotating member can move in a generally radial direction of the non-rotating sleeve, and the resilient member acts on the anti-rotating member and provides acting force being substantially radially outward for the anti-rotating member.

Abstract: A rotary cutting tool, which may be a reamer for enlarging an underground borehole or a mill to remove tubing by cutting into the inside wall of the tubing, has a plurality of cutter assemblies distributed azimuthally around a longitudinal axis of the tool, wherein each cutter assembly includes a supporting structure bearing a sequence of cutters which extends axially along the tool with leading surfaces facing in a direction of rotation of the tool. The cutters of each sequence are positioned at a plurality of circumferential positions such that no more than three cutters of the sequence are aligned on any line parallel to the longitudinal axis of the tool. In an overlapping arrangement, a plurality of cutters in the sequence may have a leading face circumferentially behind the leading face but ahead of the trailing end of at least one other cutter.

Abstract: A retractable and extendable cone-type reamer is positioned on a drill string. An extension and retraction mechanism is configured to extend and retract the cone-type reamer. A hydraulic power unit is configured to control the extension and retraction mechanism. Sensors are positioned on or within the cone-type reamer. The sensors are configured to detect parameters of the wellbore-type hole opening system. A controller is operatively coupled to the hydraulic power unit and the sensors. The controller is configured to be positioned in a wellbore. The controller is configured to receive signals from the sensors. The signals represent the parameters detected by the sensors. The controller is configured to identify the parameters represented by the signals. The controller is configured to adjust a parameter of a wellbore-type hole opening operation in response to the received signals.

Abstract: A reaming tool for enlarging an underground borehole comprises a plurality of cutter assemblies distributed azimuthally around a longitudinal axis of the tool, wherein each cutter assembly includes a supporting structure bearing a sequence of cutters which have hard surfaces exposed and facing in a direction of rotation of the tool. The outer surface of the support structure on each cutter assembly includes zones which each face towards an end of the assembly and is configured such that as it extends circumferentially relative to the tool axis in the direction opposite to rotation of the tool, it also extends away from an end of the assembly.

Abstract: A reaming tool for enlarging an underground borehole comprises a plurality of cutter assemblies (251, 252, 253) distributed azimuthally around a longitudinal axis of the tool, wherein each cutter assembly comprises support structure bearing a sequence of cutters (211-214) with leading surfaces facing in a direction of rotation of the tool and the sequence of cutters extends axially along the tool from an axial end (202) of the tool with the cutters positioned at radial distances from the tool axis which progressively increase as the sequence extends away from the axial end of the tool. The cutter assemblies include guiding structure (261-264) which is positioned circumferentially ahead of the leading faces of cutters of the sequence on the assembly.

Abstract: A reaming tool for enlarging an underground borehole has a plurality of cutter assemblies distributed azimuthally around a longitudinal axis of the tool. First, second and possibly more cutter assemblies each have an axially extending length comprising supporting structure bearing a sequence of cutters which have hard surfaces facing in a direction of rotation of the tool and are distributed axially along the length. A plurality of the cutters on the second cutter assembly are at axial positions relative to the tool which are intermediate between axial positions of the cutters on the first cutter assembly. Cutters on further assemblies may also be at intermediate axial positions. Cutters in the overall plurality of sequences are positioned at radial distances from the tool axis which increase as axial distance from an end of the tool increases.

Abstract: Expandable reamer assemblies include an expandable reamer module and an activation module. An outer tubular body of the activation module is rigidly coupled to a tubular body of the expandable reamer module, and an activation member of the activation module is coupled to a sleeve of the expandable reamer module, the sleeve coupled to at least one blade and configured to move the at least one blade into an extended position. The sleeve moves axially responsive to axial movement of the activation member. Bottom-hole assemblies include an expandable reamer module and an activation module. The activation module is coupled to the expandable reamer module and configured to provide a motive force to the sleeve to move the sleeve opposite a direction of flow of drilling fluid. Methods of using expandable reamer modules include pairing two substantially identical expandable reamer modules and two respective different activation modules.

Abstract: A milling tool includes a cutting insert coupled to a movable blade. The movable blade may change from a retracted to an expanded state to engage and cut downhole casing. A cutout initiation region of the movable blade makes contact with the downhole casing, and cutting inserts with turning portions designed to cut in a turning manner may be located in the cutout initiation region. Cutting inserts with milling portions designed to cut in a face-milling manner may be located outside the cutout initiation region. Some cutting inserts may include both turning portions and milling portions.

Abstract: An extendable drilling tool, the extendable tool moving in a drilling direction and including a body with a longitudinal axis and at least one arm that is mobile relative to the body in a direction of movement that forms a first angle with the longitudinal axis that is non-zero, less than 45°, and open upstream according to the direction of drilling. The extendable tool includes a piston that is mobile in a direction parallel to the longitudinal axis, the piston being located downstream according to the direction of drilling relative to the arm, the piston including at least one bearing surface that works with at least one arm and that forms with the longitudinal axis a second angle that is non-zero, less than 90°, and open downstream according to the direction of drilling.

Abstract: A progressing cavity-type drilling motor having an electrical generator disposed within the rotor of the drilling motor. In some embodiments, the electrical generator produces electrical energy from a flow of drilling fluid through a bore in the rotor. In other embodiments, the electrical generator produces electrical energy by harnessing the kinetic energy of the rotor as the drilling motor is used to drill into a formation. The electrical energy generated by the generator can be stored or used to power sensors, actuators, control systems, and other downhole equipment.

Abstract: Expandable reamer assemblies include an expandable reamer module and an activation module. An outer tubular body of the activation module is rigidly coupled to a tubular body of the expandable reamer module, and an activation member of the activation module is coupled to a sleeve of the expandable reamer module, the sleeve coupled to at least one blade and configured to move the at least one blade into an extended position. The sleeve moves axially responsive to axial movement of the activation member. Bottom-hole assemblies include an expandable reamer module and an activation module. The activation module is coupled to the expandable reamer module and configured to provide a motive force to the sleeve to move the sleeve opposite a direction of flow of drilling fluid. Methods of using expandable reamer modules include pairing two substantially identical expandable reamer modules and two respective different activation modules.

Abstract: An under-reamer comprises a body and extendable cutters mounted on the body. The under-reamer is configured to be cycled between a first configuration in which the cutters are retracted and a second configuration in which the cutters are movable between retracted and extended positions. A control mechanism is provided and is configurable to prevent the under-reamer cycling between the first and second configurations and thus maintain the under-reamer in a selected one of the first and second configurations.

Abstract: A steerable earth boring assembly which includes an annular collar and a drive shaft with a drill bit, where the shaft pivots with respect to the collar. An upstream portion of the shaft inserts into an orientation sleeve which resides in the collar. An axial bore is obliquely formed through the sleeve, and in which the upstream portion inserts. Rotating the sleeve causes precession of the upstream portion, thereby pivoting the drill bit obliquely to the collar. Selective rotation of the sleeve orients the drill bit into a designated orientation for forming a deviated wellbore. Included in the assembly is a flow tube with an end in sealing contact with the drive shall.

Abstract: An underreamer for connection with a rotary pipe string includes inner and outer body sections which form a body structure to provide a fluid flow path therethrough for communicating with piston and cylinder means formed between the body sections for receiving drilling fluid to effect telescopic movement between the body sections permitting engagement of cutter arms and support of said cutter arms on the outer body of the underreamer utilizing a slideable, non-pivoting stop block. Cutter arms are pivotally mounted on the inner body section and, upon engagement of the cutter arms to effect underreaming are fully supported on the outer body section thereby minimizing damage from vibration and repeated use on the threaded inner body sections.

Abstract: Expandable reamer assemblies include an expandable reamer module and an activation module. An outer tubular body of the activation module is rigidly coupled to a tubular body of the expandable reamer module, and an activation member of the activation module is coupled to a sleeve of the expandable reamer module, the sleeve is coupled to at least one blade and configured to move the at least one blade into an extended position. The sleeve moves axially responsive to axial movement of the activation member. Bottom-hole assemblies include an expandable reamer module and an activation module. The activation module is coupled to the expandable reamer module and configured to provide a motive force to the sleeve to move the sleeve opposite a direction of flow of drilling fluid. Methods of using expandable reamer modules include pairing two substantially identical expandable reamer modules and two respective different activation modules.

Abstract: Embodiments of the present disclosure are directed towards a downhole slot cutter. The downhole slot cutter a housing of the downhole slot cutter configured to be inserted into a tubular positioned within a wellbore, and a plurality of dies supported by the housing, wherein the plurality of dies is configured to extend radially outward from the housing.

Abstract: The expandable tools disclosed herein may be used as an underreamer to enlarge a borehole, or may be used to stabilize a drilling system in a previously underreamed borehole or in a borehole that is being underreamed while drilling progresses. At least one moveable arm, which translates between a collapsed and expanded position in response to a differential pressure between the axial flowbore and the wellbore, includes a borehole-engaging surface with cutting elements and at least one nozzle to direct a fluid across the borehole-engaging surface. Flow directing elements on the external surface of the tool may be used to decrease the flow area in an annulus between the tool and the wellbore and directs fluid flow in the annulus toward the borehole-engaging surface.

Abstract: A downhole tool includes a pressure activated flow switch for selectively actuating and deactuating a device, such as a reaming block. The flow switch is deployed external to the flow bore and includes a flow piston configured to reciprocate between axially opposed open and closed positions such that the device is actuated when the flow piston is in the open position and deactuated when the flow piston is in the closed position. The flow piston is configured to translate from the closed position to the open position when a differential pressure exceeds a predetermined threshold. The flow piston may be further configured to remain in the open position at differential pressures less than the threshold.

Abstract: A status indicator for determining a position of an extendable member in an expandable apparatus. The status indicator is configured to decrease a cross-sectional area of a portion of a fluid path extending through an expandable causing a pressure of a fluid within the fluid path to increase when an extendable member of the expandable apparatus is in an extended position. By determining the pressure of the fluid within the fluid path, one can determine the position of the status indicator within the fluid path and thereby determine whether the extendable member of the expandable apparatus is in the extended or a retracted position.

Abstract: An under-reamer includes a body and extendable cutters mounted on the body. The under-reamer is configured to be cycled between a first configuration in which the cutters are retracted and a second configuration in which the cutters are movable between retracted and extended positions. A control mechanism is provided and is configurable to prevent the under-reamer cycling between the first and second configurations and thus maintains the under-reamer in a selected one of the first and second configurations.

Abstract: Expandable apparatus for use in subterranean boreholes include at least one member configured to move between a retracted position and an extended position. Components of the expandable apparatus may include at least one surface for removing debris proximate to the tubular body. Components of the expandable apparatus may be configured to enable the expandable apparatus to increase a diameter of a subterranean borehole by greater than twenty percent. Components of the expandable apparatus may be configured to restrict fluid flow to nozzle assemblies. The expandable apparatus may include a protect sleeve having a push sleeve disposed therein. Methods of operating an expandable apparatus may include removing debris with a surface of the expandable apparatus. Methods of operating an expandable apparatus may also include selectively flowing fluid to nozzle assemblies.

Abstract: Described herein is a reamer tool (100) having a body (105) with bays (115) in which cutter arms (110) are mounted for deployment between a stowed position and a deployed position. A deployment mechanism is provided for deploying the cutter arms from their stowed position to their deployed position that maintains each cutter arm in a position that is substantially parallel to a longitudinal axis of the body (105) whilst in its stowed position and in its deployed position as well as during its deployment from its stowed position to its deployed position. A control module (300) is also described for controlling the deployment of the cutter arms (110). The control module (300) comprises a motor (310), a gearing mechanism (315) and a moveable element (320) that closes a port (385) in a first position and opens the port (385) in a second position.

Abstract: Expandable reamers for enlarging wellbores include a tubular body and one or more blades configured to extend and retract. A sleeve member within the tubular body has open ends to allow fluid to flow therethrough. A fluid port extends through a wall of the sleeve member. A restriction member within the sleeve is movable between first and second positions. In the first position, fluid flow through the downhole end of the sleeve is generally unimpeded, and fluid flow through the fluid port is generally impeded. In the second position, fluid flow through the downhole end of the sleeve member is generally impeded, and fluid flow through the fluid port is generally unimpeded. The restriction member may be configured to move responsive to changes in the rate of fluid flow through the sleeve member. Methods of using such reamers are also disclosed.

Abstract: Expandable apparatus for use in subterranean boreholes include a tubular body having at least one opening and at least one member positioned within the at least one opening. The member is configured to move between a retracted position and an extended position. A sleeve member including a constricted portion may be disposed in the tubular body and may selectively retain the at least one member in the retracted position. In some embodiments, the sleeve member may be biased in an initial position. Methods of moving a member of an expandable apparatus include repeating retracting and expanding of the member. Methods of triggering an expandable apparatus include forming a constriction in a fluid flow path extending through a sleeve member to move the sleeve member in a downhole direction responsive to fluid flow.

Abstract: Device (1) for consolidating soils by mechanical mixing and injection of consolidating fluids is designed to be connected to one or more drilling rods and to carry out operations of drilling and mixing. The device has a main body (10), one or more blades (30) (30?) (30?), which are mobile with respect to the body (10) and are constrained by cams (22) to a central structure (20) internal to the body (10). The device (1) has channels for the flow of fluids (40), which are connected in a liquid-tight way to at least one sprayer; a relative motion is generated between the central structure (20) and the external body (10) as a function of the pressure of a liquid introduced into the channels for the flow of fluids (40), which brings about opening of the blades (30) (30?) (30?).

Abstract: Expandable reamers for enlarging wellbores include a tubular body and one or more blades configured to extend and retract. A sleeve member within the tubular body has open ends to allow fluid to flow therethrough. A fluid port extends through a wall of the sleeve member. A restriction member within the sleeve is movable between first and second positions. In the first position, fluid flow through the downhole end of the sleeve is generally unimpeded, and fluid flow through the fluid port is generally impeded. In the second position, fluid flow through the downhole end of the sleeve member is generally impeded, and fluid flow through the fluid port is generally unimpeded. The restriction member may be configured to move responsive to changes in the rate of fluid flow through the sleeve member. Methods of using such reamers are also disclosed.

Abstract: A downhole tool includes a pressure activated flow switch for selectively actuating and deactuating a device, such as a reaming block. The flow switch is deployed external to the flow bore and includes a flow piston configured to reciprocate between axially opposed open and closed positions such that the device is actuated when the flow piston is in the open position and deactuated when the flow piston is in the closed position. The flow piston is configured to translate from the closed position to the open position when a differential pressure exceeds a predetermined threshold. The flow piston may be further configured to remain in the open position at differential pressures less than the threshold.

Abstract: An expandable apparatus may comprise a tubular body, a valve piston and a push sleeve. The tubular body may comprise a fluid passageway extending therethrough, and the valve piston may be disposed within the tubular body, the valve piston configured to move axially within the tubular body responsive to a pressure of drilling fluid passing through the fluid passageway and configured to selectively control a flow of fluid into an annular chamber. The push sleeve may be disposed within the tubular body and coupled to at least one expandable feature, the push sleeve configured to move axially responsive to a flow of fluid into the annular chamber extending the at least one expandable feature.

Abstract: Expandable reamers for enlarging boreholes in subterranean formations include a tubular body and at least one member positioned in openings in the tubular body. The at least one member is configured to move between retracted and extended positions. A push sleeve is disposed at least partially within the tubular body and coupled to the at least one member. The push sleeve moves axially upward to move the at least one member to the extended position in response to a pressure of drilling fluid passing through a drilling fluid flow path in the tubular body. The push sleeve moves axially downward to move the at least one member to the retracted position in response to a pressure of drilling fluid upon a restrictive element disposed within the fluid passageway. The restrictive element disposed within the fluid passageway may be discarded from the fluid passageway by increasing the flow rate through the drilling fluid flow path.

Abstract: Expandable reamer tools include an outer body, a fluid passageway extending through the outer body, and at least one blade configured to slide relative to the outer body between a retracted position and an expanded position. In some embodiments, the tools may include a formation-engaging surface comprising a gage area. In other embodiments, the tools may include a radially recessed area extending from a back edge of the formation-engaging surface. Methods for removing such expandable reamer tools from a borehole are also disclosed.

Abstract: A downhole tool including a tubular body having an upper connection and a lower connection and an axial borehole therethrough, wherein the upper and lower connections are configured to connect to a drilling assembly, at least one expandable component coupled to the tubular body and configured to selectively extend radially therefrom, and an actuation assembly configured to selectively actuate, deactuate, and reactuate the at least one component. A method of selectively actuating a downhole tool, wherein the downhole tool comprises a tubular body with an axial borehole therethrough and at least one component, the method including circulating a drilling fluid in the axial borehole of the downhole tool, actuating the at least one component, deactuating the at least one component, and reactuating the at least one component.

Abstract: An underreamer that can be assembled easily is formed from a tubular body having a flow tube running to a distal end delivering fluid which moves an actuator against the underreamer arms which are hinged to a moveable stop block and stopped to positively seat the arm at the end of a key slot to rigidly hold the underreamer arm in full extension during operations. Once hydraulic pressure is released, a spring moves the arm down the slot to a position where the arm can be removed from the slot in the underreamer body. A lower sub assembly is affixed to the underreamer body to prevent premature back off of the lower sub. Jets are disposed on either side of the underreamer to remove cuttings from the well bore. The tool is adaptable in the field for several hole sizes by adjustment in the length of the stop block and the angle of the flat on the top side of the key.

Abstract: A down hole well bore apparatus to underream and remove rock or cement or other material, cut or mill casing, clean or scrape casing, or centralize a drill string, which has a rotor which actuates blades, a compact overall length and can be operated with normal or reverse circulation. Simultaneous operations or multiple sequential operations can be made without removing the drill string.

Abstract: An expandable reamer apparatus and methods for reaming a borehole, wherein a laterally movable blade carried by a tubular body may be selectively positioned at an inward position and an expanded position. The laterally movable blade, held inwardly by blade-biasing elements, may be forced outwardly by drilling fluid selectively allowed to communicate therewith by way of an actuation sleeve disposed within the tubular body. Alternatively, a separation element may transmit force or pressure from the drilling fluid to the movable blade. Further, a chamber in communication with the movable blade may be pressurized by way of a downhole turbine or pump. A ridged seal wiper, compensator, movable bearing pad, fixed bearing pad preceding the movable blade, or adjustable spacer element to alter expanded blade position may be included within the expandable reamer. In addition, a drilling fluid pressure response indicating an operational characteristic of the expandable reamer may be generated.

Abstract: The present invention relates to downhole tools, and in particular an underreamer tool for use in a wellbore of an oil or gas well and a method of actuation. In an embodiment, the underreamer tool has body having a longitudinal axis and a fluid conduit, a tool element and an actuation device configured to urge the tool element relative to the body from a first configuration into a second configuration. In this embodiment, a portion of the tool has a curved actuation surface and the tool element is urged across the curved actuation surface the tool element is moved radially with respect to the body of the tool. Typically, the actuation device may include a piston driven by pressure of fluid circulated through the fluid flow conduit.

Abstract: An expandable reamer apparatus for drilling a subterranean formation may include a tubular body, one or more blades, each blade positionally coupled to a sloped track of the tubular body, a push sleeve and a drilling fluid flow path extending through an inner bore of the tubular body for conducting drilling fluid therethrough. Each of the one or more blades may be configured to ream a subterranean formation. The push sleeve may be disposed in the inner bore of the tubular body and coupled to each of the one or more blades so as effect axial movement thereof along the track to an extended position responsive to exposure to a force or pressure of drilling fluid in the flow path of the inner bore. Each blade may include one or more roller elements for reaming a wellbore.

Abstract: An expandable reamer apparatus and methods for reaming a borehole, wherein a laterally movable blade carried by a tubular body may be selectively positioned at an inward position and an expanded position. The laterally movable blade, held inwardly by blade-biasing elements, may be forced outwardly by drilling fluid selectively allowed to communicate therewith by way of an actuation sleeve disposed within the tubular body. Alternatively, a separation element may transmit force or pressure from the drilling fluid to the movable blade. Further, a chamber in communication with the movable blade may be pressurized by way of a downhole turbine or pump. A ridged seal wiper, compensator, movable bearing pad, fixed bearing pad preceding the movable blade, or adjustable spacer element to alter expanded blade position may be included within the expandable reamer. In addition, a drilling fluid pressure response indicating an operational characteristic of the expandable reamer may be generated.

Abstract: An expandable reamer apparatus for drilling a subterranean formation includes a tubular body, one or more blades, each blade positionally coupled to a sloped track of the tubular body, a push sleeve and a drilling fluid flow path extending through an inner bore of the tubular body for conducting drilling fluid therethrough. Each of the one or more blades includes at least one cutting element configured to remove material from a subterranean formation during reaming. The push sleeve is disposed in the inner bore of the tubular body and coupled to each of the one or more blades so as effect axial movement thereof along the track to an extended position responsive to exposure to a force or pressure of drilling fluid in the flow path of the inner bore. The apparatus is provided with a caliper for measuring the actual borehole size. Remedial action may be taken based on a comparison of the actual borehole size and the intended size.

Abstract: Expandable reamer tools include an outer body, a fluid passageway extending through the outer body, and at least one blade configured to slide relative to the outer body between a retracted position and an expanded position in a direction oriented at an acute angle of less than ninety degrees (90°) to a longitudinal axis of the outer body. In some embodiments, the tools may include a moveable inner sleeve member configured to selectively allow hydraulic fluid pressure within the fluid passageway to act directly on the at least one blade. Methods for enlarging a borehole using such expandable reamer tools and methods for removing such expandable reamer tools from a borehole are also disclosed.

Abstract: A method of reducing contact pressure between bearing surfaces of a well tool can include constructing a structure which supports one bearing surface in contact with the other bearing surface, and reducing contact pressure between the bearing surfaces by relieving strain energy in the structure. A well tool can include one bearing surface which contacts another bearing surface. There is a transition between contact and lack of contact between the bearing surfaces. A structure supporting one of the bearing surfaces can have a reduced stiffness, whereby a contact pressure between the bearing surfaces is reduced at the transition. The bearing surfaces can be formed on a thrust bearing, plain bearing, or other type of bearing between components of the well tool.

Abstract: In accordance with an embodiment of the present invention, a drilling tool includes a tubular body defining a longitudinal axial cavity extending therethrough and defining at least one cutter element recess. The drilling tool also includes a cutter element at least partially disposed within the at least one cutter element recess and includes at least first and second cutting arms at least substantially disposed within the cutter element recess in a retracted position. The first and second cutting arms are operable to move from the retracted position to an extended position in which the first and second cutting arms extend at least partially beyond a periphery of the tubular body. The first and second cutting arms and the tubular body enclose a space when the first and second cutting arms are in the extended position.

Abstract: An underreaming tool may include a tubular body, a drive tube, at least one blade element (“the blade element”), at least one wedge element (“the wedge element”), and a stop mechanism. The drive tube may include at least one longitudinal groove (“the longitudinal groove”) axially disposed along a length of the drive tube. The wedge element may include a first side having at least one lateral projection (“the lateral projection”) configured to axially slide into the longitudinal groove to couple the wedge element to the drive tube. The stop mechanism comprises a threaded sleeve configured to screw onto the drive tube to lock the wedge element in the longitudinal groove once the lateral projection is slid into the longitudinal groove.

Abstract: An expandable apparatus for use in a borehole includes a tubular body having at least one opening extending between a longitudinal bore of the tubular body and an outer surface of the tubular body and at least one member positioned within the at least one opening of the tubular body. The member is configured to move between a retracted position and an extended position. An actuation structure is positioned within the tubular body. The actuation structure is coupled to the at least one member and is configured to move the at least one member from the retracted position to the extended position responsive to a flow rate of drilling fluid passing through the longitudinal bore.

Abstract: Casing cutter for severing multiple tubulars in a well bore has a pair of cutter blades pivotally mounted on a support body. The blades are pivotally mounted for gradual movement outside of the support body when downward force is applied to proximate ends of the cutter blades. The support body is rotated inside the innermost of the multiple tubulars, while the cutter blades sever the tubulars of progressively increasing diameter. Should the cutter blades or pivotal connections become unusable, the tool body can be rotated about the vertical axis and secured to a downhole string by the opposite end. A substitute pair of cutter blades are then engaged on the tool body and operated to cut the casings similar to the first set of the cutter blades.

Abstract: An expandable reamer apparatus for drilling a subterranean formation includes a tubular body, one or more blades, each blade positionally coupled to a sloped track of the tubular body, a push sleeve and a drilling fluid flow path extending through an inner bore of the tubular body for conducting drilling fluid therethrough. Each of the one or more blades includes at least one cutting element configured to remove material from a subterranean formation during reaming. The push sleeve is disposed in the inner bore of the tubular body and coupled to each of the one or more blades so as effect axial movement thereof along the track to an extended position responsive to exposure to a force or pressure of drilling fluid in the flow path of the inner bore.