Abstract: The present disclosure provides an apparatus and method for cleaning rock debris when deep-water surface drilling is done. The apparatus for cleaning rock debris when deep-water surface drilling is done comprises: an open barrel having an open through groove which is axially provided; a plurality of debris cleaning mechanisms connected to the open barrel at an interval in a circumferential direction of the open barrel, wherein each of the debris cleaning mechanisms comprises: a fixed block connected to an outer wall of the open barrel; a debris cleaning leg having one end rotatably connected to the fixed block, and the other end provided with a debris cleaning impeller; and a pull rod having one end connected to the outer wall of the open barrel above the fixed block, and the other end movably connected to the debris cleaning leg.

Abstract: An anchor rod multi-section reaming machine tool and an application thereof are provided. The machine tool is used cooperatively with an anchor rod drill rig. A hydraulic cylinder is fixed at a lower end of a drill rod of the anchor rod drill rig. A lower end of the piston rod is fixed at an upper portion of an arch pressing device fixing disc. An arch pressing device comprises a pair of upper arch arms and a pair of lower arch arms, upper ends of the upper arch arms are rotatably connected with a central position of a lower portion of the arch pressing device fixing disc, lower ends of the upper arch arms are rotatably connected with upper ends of the lower arch arms, and lower ends of the lower arch arms are rotatably connected with a central position of an upper portion of a base plate.

Abstract: A packer apparatus usable in a downhole well casing or an open borehole to provide an annular seal in the well casing or borehole. The packer apparatus includes an activation member disposed in body wherein the activation member is moveable relative to the body to deform an elastomeric packer element outwardly relative to the body to form an annular seal in a well casing in use. A plurality of pistons is arranged to move the activation member relative to the body, each piston being disposed in a respective pressure chamber arranged to be filled with fluid in response to an increase in fluid pressure in the body.

Abstract: A stabilizer design for improving the likelihood of recovery of a drill string when obstructions are encountered in a wellbore is disclosed herein. The stabilizer includes a tubular body, a track, and a stabilizer blade. The track is disposed along the tubular body. The stabilizer blade is operatively coupled to the track and is configured to slide along the track from a first position to a second position.

Abstract: A downhole tool configured to enlarge a borehole may include at least one blade extending laterally from a central portion of the tool. The one or more blades may each include a gage portion, and cutting elements comprising substantially circular cutting faces may be affixed to each of the one or more blades. Each of the one or more cutting elements may include a cutting edge comprising an arcuate peripheral cutting face portion for contacting the borehole. Cutting faces of at least one cutting element on a gage portion of the at least one blade may exhibit a cutting face back rake angle greater than a cutting face back rake angle of cutting elements on at least one other portion of the at least one blade.

Abstract: A tool control mechanism is configured to activate and deactivate a drill string tool by hydraulic action of drilling fluid. The tool control mechanism is switchable between an activation mode and a deactivation mode. In the activation mode, a hydraulic activator ram is coupled to a tool switch member to drive the switch member in an activation direction in response to above-threshold drilling fluid conditions. In the deactivation mode, a deactivator ram is coupled to the tool switch member to drive the switch member in a deactivation direction opposite to the activation direction, when above-threshold drilling fluid conditions occur. The tool control mechanism is switchable between the activation mode and the deactivation mode by operator-controlled drilling fluid pressure variations.

Abstract: An underreamer for increasing a diameter of a wellbore. The underreamer may include a body with first and second cutter blocks coupled to the body. The first cutter block may have a recess formed therein, and the second cutter block may be positioned in the recess. The first and second cutter blocks may move between retracted and expanded states. In the retracted state, the first and second cutter blocks may have an outer diameter less than or equal to an outer diameter of the body. In the expanded state, the first and second cutter blocks may have different outer diameters, with each being greater than the outer diameter of the body. A method may include running the underreamer into a wellbore, expanding the first and second cutter blocks, and moving the underreamer axially in the wellbore to increase the diameter of the wellbore.

Abstract: A method, device, and system is described herein for pushing a rotary drill bit. Pushing the rotary drill bit can include receiving a target direction in a formation to push the rotary drill bit while drilling a wellbore in a formation. Pushing the rotary drill bit can also include opening, at a first rotational position of a rotary bit pushing device disposed proximate to the rotary drill bit within the wellbore, a first inlet port of a first flow regulator. Pushing the rotary drill bit can further include closing, after the first rotational position of the rotary bit pushing device, the first inlet port. Pushing the rotary drill bit can also include sending, to a second flow regulator of the rotary bit pushing device, a second quantity of drilling fluid.

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: A tool for boring holes in soil includes an elongated tubular housing which has disposed through its length a bore having an upper opening coupleable to a vacuum source and a lower opening coupled to the bore of a ring-shaped bore head having circumferentially spaced apart cutting teeth protruding downwards from the bore head. A zig-zag shaped unclogger bar disposed coaxially through the bore head and rotated by a drive shaft disposed coaxially through the tubular and housing and protruding through a bearing in an upper end of the housing and driven by a rotary power source such as an electric motor fixed to the housing fragments lumps of clay or wet soil lodged in the bore of the housing, facilitating removal of soil and clay, which are severed by twisting the tool around its longitudinal axis by manipulating handle bars protruding from the upper end of the housing.

Abstract: A method for conducting a wellbore operation includes disconnecting a radially projecting member from a first sub without uncoupling a second sub from the first sub. The method may include also coupling the first sub to the second sub with a connector that includes an electrical connection. An associated apparatus may include a sub having at least one conductor connected to a connector; and at least one radially projecting member removably coupled to the sub.

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: Expandable apparatus for use in subterranean boreholes include at least one member configured to move between a retracted position and an extended position. A latching member disposed in the tubular body may selectively retain the at least one member in the retracted position. Methods of operating an expandable apparatus include securing at least one member of the expandable apparatus in a retracted position by engaging an inner wall of a tubular body with at least one latch member disposed in at least one aperture formed in a latch sleeve.

Abstract: The present invention is a subsurface formation cutter for directional cutting into a subterranean formation. The subsurface formation cutter includes a transmission unit, a cutter bit, a bit brace, and a ram unit. The transmission unit has a driver shaft operatively connected to a bottom hole assembly. The cutter bit has a connector member, a cutter body rotatably coupled to the connector member, and a bit shaft connected to the cutter body. The bit shaft is operatively coupled to the driver shaft of the transmission unit. The ram unit has a moveable ram shaft connected to a traveling member. The bit brace is pivotably connected to the connector member and the traveling member. A connection member is attaches the ram unit to the transmission unit, and is configured to receive and guide the traveling member to travel in a direction parallel with a longitudinal axis of the subsurface formation cutter.

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 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 steerable drilling apparatus includes a control system inside a cylindrical housing connected to a drill bit having radially-extendable pistons. A fluid-metering assembly directs a piston-actuating fluid into fluid channels leading to respective pistons. The control system controls the fluid-metering assembly to allow fluid flow to selected pistons, causing the actuated pistons to temporarily extend in the opposite direction to a desired wellbore deviation, thereby deflecting the drill bit away from the borehole centerline. An upper member in the fluid-metering assembly can be moved to stabilize, steer, and change TFA within the drill bit. The control system and drill bit are connected so as to facilitate removal to change the drill bit's steering section and cutting structure configuration or gauge simultaneously. The apparatus may incorporate a fluid filter module mounted to the control system. The pistons may incorporate auxiliary cutting elements to provide near-bit reaming capability.

Abstract: A downhole tool includes a body having a bore extending, at least partially therethrough. A component is disposed within the bore and arranged and designed to move axially from a first position to a second position within the bore. An axial end portion of the component has a first contact surface that is oriented at an angle from about 1° to about 45° with respect to a longitudinal axis extending through the component.

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: A drilling apparatus includes a tubular body including an upper connection and a lower connection with a drill bit disposed thereon, and an axial borehole therethrough, wherein the upper connection is configured to attach to a drillstring, primary cutter blocks coupled to the tubular body and configured to selectively expand radially therefrom. The drilling apparatus further includes backup cutter blocks coupled to the tubular body and configured to selectively expand radially therefrom, and an activation system configured to selectively expand and collapse the primary and backup cutter blocks in response to changes in weight applied to the primary and backup cutter blocks.

Abstract: In one aspect, a drill bit is disclosed that in one embodiment includes a plurality of elements that extend and retract from a surface of the drill bit, wherein the plurality of such elements are in fluid communication with each other to compensate for differing forces applied to such elements during drilling operations. In another aspect, a method of drilling a wellbore is provided that in one embodiment includes: conveying a drill string having a drill bit at an end thereof, wherein the drill bit includes a plurality of elements that extend and retract from a surface of the drill bit, wherein the plurality of such elements are in fluid communication with each other to compensate for differing forces applied to such elements during drilling operations; and drilling the wellbore using the drill string.

Abstract: An underreamer for increasing a diameter of a wellbore. The underreamer may include a body having an axial bore extending at least partially therethrough. An electromagnetic activation system may be disposed at least partially within the bore of the body. A valve may be disposed within the bore of the body and coupled to the electromagnetic activation system. The valve may include a mobile element and a static element. The mobile element may be coupled to the electromagnetic activation system and move from a first position where the mobile element obstructs fluid flow through the valve to a second position where the mobile element permits fluid flow through the valve. A cutter block may be movably coupled to the body and move radially-outward as the mobile element moves from the first position to the second position.

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: 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: A cutting structure for use with a reamer in enlarging a borehole in a subterranean formation includes a plurality of cutter blocks, radially extendable from a reamer body away from a central axis of the reamer body, each of the plurality of cutter blocks comprising at least one cutter blade thereon, wherein an angular spacing about the central axis of the reamer body between the at least one cutter blade on each of the plurality of cutter blocks is unequal.

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: An underreamer for increasing a diameter of a wellbore. The underreamer includes a body having an axial bore extending at least partially therethrough. A sleeve is arranged and designed to move a first axial distance within the body. A cutter block is movably coupled to the body. The cutter block is arranged and designed to move at least the first axial distance with respect to the body to contact the sleeve in response to hydraulic pressure in the bore. The cutter block moves from a first outer diameter to a second outer diameter as the cutter block moves the first axial distance.

Abstract: A pressurized fluid flow system for a normal circulation down-the-hole hammer comprises a cylinder coaxially disposed in between an outer casing and a piston which reciprocates due to changes in pressure of pressurized fluid contained inside a front chamber and rear chamber located at opposites sides of the piston, supply/discharge of fluid to/from these chambers being conducted through a supply chamber and a discharge chamber defined by recesses on the inner surface of the casing and separated by a dividing wall, the front/rear chambers' in/out fluid flow being controlled solely by the overlap of the piston and the cylinder. A hammer having this system comprises a drill bit with one or more flushing passages which extend from channels cooperatively formed between splines on the inner surface of the driver sub and on the outer surface of the drill bit shank up to the front face of the drill bit.

Abstract: The present invention relates to a downhole tool extending in a longitudinal direction, comprising a tool housing; an arm assembly pivotally mounted about a pivot point fixed in relation to the tool housing and movable between a retracted position and a projecting position in relation to the tool housing; an arm activation assembly for moving the arm assembly between the retracted position and the projecting position, the arm activation assembly being arranged inside the tool housing and having a first end face and a second end face adapted for being connected with the end faces of other arm activation assemblies; wherein the arm activation assembly comprises: a piston housing having a piston chamber extending in the longitudinal direction of the downhole tool and comprising: a first piston housing part, a second piston housing part removably connected to the first piston housing part, a piston member arranged inside the piston housing and connected with the arm assembly, the piston member being movable in th

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: 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. 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: A drilling assembly for drilling a subterranean wellbore includes an expandable reamer and an expandable stabilizer. The expandable reamer and the expandable stabilizer each have a tubular body with a longitudinal axis and a drilling fluid flow path extending therethrough. A plurality of blades is carried by the reamer and a plurality of bearing pads is carried by the stabilizer. The blades and bearing pads are outwardly movable from a retracted position to an extended position with respect to the longitudinal axes of the reamer and stabilizer, respectively. The reamer and stabilizer each include an actuation device for moving the blades and bearing pads, respectively, from the retracted position to the extended position.

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 cutting structure for use with a reamer in enlarging a borehole in a subterranean formation includes a plurality of cutter blocks, radially extendable from a reamer body away from a central axis of the reamer body, each of the plurality of cutter blocks comprising at least one cutter blade thereon, wherein an angular spacing about the central axis of the reamer body between the at least one cutter blade on each of the plurality of cutter blocks is unequal.

Abstract: An articulated reaming tool is provided in casing or liner drilling on or through the tubular wall with the articulation occurring from within the tubular. Outer limit travel stops are contemplated to optionally be used to retain the elements or blades to the tubular. In the case of liner drilling the drill string has an exterior protrusion to engage the movable components that ream and extend them to increase the clearance for the tubular as the tubular advances when more hole is made.

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 milling tool for enlarging portions of a wellbore. The milling tool includes a housing that defines a central bore along its length. A piston is moveably disposed within the central bore, and axial movement of the piston moves support arms radially outwardly from the housing. The support arms carry milling blades for enlarging portions of a wellbore.

Abstract: A drill bit for use in drilling a wellbore and that can be used for fracturing the subterranean formation surrounding the wellbore. Included on the bit body is a packer for sealing against the wellbore wall during fracturing. A chamber in the drill bit houses a valve assembly for selectively diverting fluid between use in drilling and for use in fracturing. The fluid is delivered through a drill string that attaches to an upper end of the bit. The valve assembly can be shuttled between drilling and fracturing configurations by selectively adjusting an amount and/or pressure of the fluid flowing in the drill string.

Abstract: A down hole tool includes a tool body, a fluid cavity, a magnetorheological fluid disposed in the fluid cavity, and an electrical control unit in communication with the MR fluid. The electrical control unit is configured to adjust a viscosity of the MR fluid by varying a magnetic field.

Abstract: A steerable drilling apparatus includes a control system inside a cylindrical housing connected to a drill bit having radially-extendable pistons. A fluid-metering assembly directs a piston-actuating fluid into fluid channels leading to respective pistons. The control system controls the fluid-metering assembly to allow fluid flow to selected pistons, causing the actuated pistons to temporarily extend in the opposite direction to a desired wellbore deviation, thereby deflecting the drill bit away from the borehole centerline. An upper member in the fluid-metering assembly can be moved to stabilize, steer, and change TFA within the drill bit. The control system and drill bit are connected so as to facilitate removal to change the drill bit's steering section and cutting structure configuration or gauge simultaneously. The apparatus may incorporate a fluid filter module mounted to the control system. The pistons may incorporate auxiliary cutting elements to provide near-bit reaming capability.

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: A downhole tool string component has at least one end adapted to connect to an adjacent tool sting component and a bore adapted to accommodate a flow of drilling fluid. A turbine is disposed within the bore and an actuating assembly is arranged such that a clutch may mechanically connect and disconnect with the turbine.

Abstract: A tool comprising a fluid path defined by a bore formed within a tubular body includes a guided sleeve and a reciprocating sleeve disposed within the bore. A gearwheel is located on an outer surface of the guided sleeve and at least one pawl located on an inner surface of the reciprocating sleeve. When the reciprocating sleeve translates axially, it rotates in a first direction. As the reciprocating sleeve rotates, the at least one pawl pushes the gearwheel and causes the guided sleeve to rotate in the first direction into a new position.

Abstract: A tubular body with an axial bore includes an upper connection attached to a drillstring and a lower connection with a drill bit disposed thereon. Primary and backup cutter blocks are coupled to the tubular body and configured to selectively expand radially therefrom. An activation system within the tubular body is configured to selectively expand and collapse the primary and backup cutter blocks in response to changes in weight applied to the primary and backup cutter blocks.

Abstract: Various embodiments of an expandable downhole tool for use in drilling of a wellbore are disclosed. 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. The various embodiments of the expandable tools disclosed herein have a higher hydraulic capacity than prior art underreamers. An increase in hydraulic energy delivered to the cutting structures may advantageously improve the rate of removal of cuttings from the cutting structures (improved cuttings evacuation), may decrease cutter element wear, and may prevent damage or premature failure. Improved cuttings evacuation may also provide for improved cutting action and increased penetration rates.

Abstract: An expandable downhole tool such as an under-reamer or a stabiliser includes a mandrel mounted for linear slidable movement relative to a main body. The mandrel, together with one or more travel blocks, cause movement of a working component in an axial direction. One or more outwardly extending guide paths slidably interact with the working component to cause the working component to move between a withdrawn inoperative position and an outwardly deployed operative position. Upon increase of hydraulic pressure from below the tool, the mandrel is urged against a spring biasing the deactivated position to move axially and cause the working component to take its operative position. Upon decrease of hydraulic pressure, the spring moves the mandrel axially to cause the working component to take its withdrawn inoperative position.

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 at least one 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: The present invention provides a directional drilling apparatus and method for use in drilling bore holes. The apparatus comprises a plurality of movably mounted cutting elements, wherein the cutting elements are movable between radially retracted and extended cutting positions. A rotary valve is provided for synchronizing the movement of the cutting elements between their respective extended and retracted positions. Control of the directional drilling system is affected by synchronized movement of the cutting elements from an inner to an outer radial position in accordance with the angular position of the drill bit. Means are provided for directing high pressure cutting fluid to the region between the cutting elements and the rotatable body to prevent the accumulation of debris that could prevent movement of the cutting elements. The cutting elements enlarge the bore hole formed by the drill bit, so that the cutting elements continuously engage the wall of the bore hole.

Abstract: A packer apparatus usable in a downhole well casing or an open borehole to provide an annular seal in the well casing or borehole. The packer apparatus includes an activation member disposed in body wherein the activation member is moveable relative to the body to deform an elastomeric packer element outwardly relative to the body to form an annular seal in a well casing in use. A plurality of pistons is arranged to move the activation member relative to the body, each piston being disposed in a respective pressure chamber arranged to be filled with fluid in response to an increase in fluid pressure in the body.