Abstract: Implementations of the present invention include a core barrel assembly having a driven latch mechanism. The driven latch mechanism can lock the core barrel assembly axially and rotationally relative to a drill string. The driven latch mechanism can include a plurality of wedge members positioned on a plurality of driving surfaces. Rotation of the drill string can cause the plurality of wedge members to wedge between an inner diameter of the drill string and the plurality of driving surfaces, thereby rotationally locking the core barrel assembly relative to the drill string. The driven latch mechanism can further include a refracted groove adapted to lock the plurality of wedge members radially within the core barrel assembly, thereby allowing for faster travel within the drill string. Implementations of the present invention also include drilling systems including such driven latch mechanisms, and methods of retrieving a core sample using such drilling systems.

Abstract: A downhole tool comprises a body, an extendable cutting member operable to cooperate with a hydraulically actuated cam member, and a cam member lock. The lock is configurable to be activated downhole to restrict movement of the cam member relative to the body and prevent extension of the cutting member.

Abstract: A shifting tool and method of shifting a downhole device that requires only a minimal profile or no profile to engage and move the movable portion of the tool. The invention comprises a ported housing assembly and at least one friction pad alignable with said at least one port and radially movable through the port between a first pad position and a second pad position. In the second pad position, the friction pad extends outside said outer diameter of said housing assembly to engage the targeted downhole device. A mandrel positioned through the ported housing has a first section with a first outer diameter and a second section with a second outer diameter, said second outer diameter being greater than said first outer diameter. The mandrel is movable between a first mandrel position and a second mandrel position. In the second mandrel position, the second outer diameter supports the friction pads in the second pad position.

Abstract: An apparatus and method for forming a borehole in an earthen formation includes a side cutting device comprised of a laterally extendable side cutting element that can be actuated from a retracted position to an extended position in which the side cutting element is selectively employed to create a larger borehole diameter in a down hole location than the remaining portion of the borehole that is closer to the borehole opening.

Abstract: Downhole cutting tools comprise a mandrel, a housing, a sleeve and a cutting blade. The mandrel comprises an inner wall surface defining a bore, and an outer wall surface. The housing is secured to the outer wall surface of the mandrel and comprises an opening. The sleeve is engaged with the outer wall surface of the mandrel. The sleeve comprises a profile that is operatively associated with a profile of the cutting blade such that movement of the sleeve causes the profile of the piston to slide along the profile of the cutting blade. In so doing, the cutting blade is radially extended outward through the opening in the housing to abrade an object located outside the housing. Movement of the sleeve can be achieved by pumping fluid down a bore in the mandrel to slide the sleeve long the outer wall surface of the mandrel.

Abstract: A shifting tool and method of shifting a downhole device that requires only a minimal profile or no profile to engage and move the movable portion of the tool. The invention comprises a ported housing assembly and at least one friction pad alignable with said at least one port and radially movable through the port between a first pad position and a second pad position. In the second pad position, the friction pad extends outside said outer diameter of said housing assembly to engage the targeted downhole device. A mandrel positioned through the ported housing has a first section with a first outer diameter and a second section with a second outer diameter, said second outer diameter being greater than said first outer diameter. The mandrel is movable between a first mandrel position and a second mandrel position. In the second mandrel position, the second outer diameter supports the friction pads in the second pad position.

Abstract: An apparatus and method for forming a borehole in an earthen formation includes a side cutting device comprised of a laterally extendable side cutting element that can be actuated from a retracted position to an extended position in which the side cutting element is selectively employed to create a larger borehole diameter in a down hole location than the remaining portion of the borehole that is closer to the borehole opening.

Abstract: An activating device is mounted in a drill string to control the activation and deactivation of an enlargement tool used for enlarging a bore hole. In order to assemble the activating device, pistons are mounted in passages and spline bars, in which plates are screwed, are then slid along T-slots of the body, through apertures of the pistons. In order to deploy the pistons and cutters, pressurized drilling fluid is applied to the inner faces of the pistons. When a pre-determined pressure level is reached, screws break and the pistons move from the inward position to the outwardly deployed position.

Abstract: A drilling device used for drilling into ground, rock or for reaming a predrilled hole includes several hammering bits in a circular shape and equipped with hammers, whereupon they together drill a hole which has a larger diameter. A casing tube can be pulled out of the hole/pushed into the drilled hole. A tubular, rotatable drill rod tube resides in the casing tube. The hammers are located in a circular shape and are each attached to the outer surface of the drill rod tube by joint/hinge attachments lying essentially in the drilling direction. Rotation of the drill rod tube in a first direction turns the hammers and associated bits outwardly from the drill rod tube, and rotation in another direction turns the hammers with their bits inwardly towards the drill rod tube so that they can be pulled away with the drill rod tube from inside the casing tube.

Abstract: An expandable downhole tool comprises a tubular body, at least one moveable arm disposed within the tubular body and being radially translatable between a retracted position and a wellbore engaging position, and at least one piston operable to mechanically support the at least one moveable arm in the wellbore engaging position when an opposing force is exerted. A method of reaming a formation to form an enlarged borehole in a wellbore comprising disposing an expandable reamer in a retracted position in the wellbore, expanding at least one movable arm of the expandable reamer radially outwardly into engagement with the formation, reaming the formation with the at least one moveable arm to form the enlarged borehole; and mechanically supporting the at least one moveable arm in the radially outward direction during reaming.

Abstract: An under reamer for expanding a borehole through an earthen formation is taught. The under reamer includes: a mandrel including an end for connection into a drill string and an opposite end and a housing including an inner bore, telescopically disposed over the mandrel and axially moveable relative to the mandrel but rotationally moveable with the mandrel. A plurality of under reamer arms are carried on the housing, the under reamer arms are formed as blocks including cutter-supporting portions in which poly-crystalline diamond compact cutters are mounted. The under reamer arms are moveable by driving the housing axially over the mandrel between a retracted position extending into the bore of the housing and an expanded position wherein the under reamers arms are pivoted out of the housing inner bore and supported therebehind by the mandrel such that the cutter-supporting portions are exposed for use to enlarge a borehole.

Abstract: A directional borehole drilling system employs a controllable drill bit, which includes one or more conical drilling surfaces. Instrumentation located near the bit measures present position when the bit is static, and dynamic toolface when the bit is rotating. This data is processed to determine the error between the present position and a desired trajectory, and the position of one or more of the bit's cones is automatically changed as needed to make the bit bore in the direction necessary to reduce the error. The controllable drill bit preferably comprises three cone assemblies mounted about the bit's central axis, each of which includes a leg with “toed-out” axle. In response to a command signal, a cone translates along the axle to cause it to bear more of the bit weight, thus excavating more deeply over the commanded toolface sector and causing the bit to bore in a preferred direction.

Abstract: An underreamer (5) is formed from a tubular body (10) having a longitudinal bore therethrough, and providing an integral piston actuator (20) responsive to hydraulic pressure to move cutters (40) into engagement with the well bore and springs (60) to resist premature engagement of the cutter arms (40) and to return the cutters (40) to the body upon conclusion of the underreaming job. Skewed longitudinal grooves (45) are formed in the tubular body thereby permitting the flowpath through the underreamer to provide substantially the same inner diameter throughout the tool (5).

Abstract: A directional borehole drilling system employs a controllable drill bit, which includes one or more drilling surfaces which are dynamically positionable in response to respective command signals. Instrumentation located near the bit measures present position when the bit is static, dynamic and drilling surface position information when the bit is rotating, and stores a desired trajectory. This data is processed to determine the error between the present position and the desired trajectory, and the position of one or more of the bit's drilling surfaces is automatically changed as needed to make the bit dig in the direction necessary to reduce the error. The controllable drill bit preferably comprises three cone assemblies mounted about the bit's central axis, each of which includes a cone and an eccentric cam that rotate about a common axle.

Abstract: A balancing structure to reduce vibration created in a rotating body by imbalance comprises an annular groove formed in the body, the groove partially filled with a quantity of solid balls. The solid balls, by only partially filling the groove, provide a stabilizing force that tends to compensate for the imbalance caused by different amounts of solids adhering to one side or the other of the body, such as for example a drilling assembly. The groove is preferably wider in a region further from the axis of rotation from the rotating body for more efficient balancing effect.

Abstract: An apparatus for shaping boreholes used in seismic operations. A drill body is attached to a drill bit and is movable in axial and rotational directions. Selective operation of the drill body causes a moveable sleeve to operate a reaming bit to extend through a drill body port and into contact with the borehole wall. A cover seals the portion of the port not covered by the reaming bit to prevent loss of a transport fluid within the drill body and to prevent drill cuttings from entering the drill body interior. The cover can be integrated within the movable sleeve or can comprise a separate component. The force exerted by the drill body against the drill bit can be proportional to the force exerted by the reaming bit against the borehole wall. The reaming bit can be operated separately or simultaneously with operation of the drill bit, and can be retracted and reset to perform another shaping operation at a different position within the borehole.

Abstract: The invention combines a mud motor, a drill bit, a transmission, an underreamer and a torque tube to simultaneously drill a well by rotating the drill bit in one direction and the underreamer in the opposite direction to balance the torque supplied to the bit and the underreamer.

Abstract: A motion compensator for drilling from a floater provides isolation of a cutting device in a well from motion of a tubular string thereabove. In a described embodiment, a motion compensator includes an anchoring device and an axial advancement device. The motion compensator is positioned in the tubular string above the cutting device. The anchoring device anchors the motion compensator in the well, while the advancement device axially advances the cutting device.

Abstract: A 2-stage underreamer for use in a subterranean wellbore includes a unitary body having upper and lower blades mounted in slots formed perpendicular to each other in the body. Separate upper and lower piston assemblies are provided for driving the blades respectively from a storage configuration in which they are located substantially completely within the slots to a use position. The blades each include a steel arm having mounted thereon a base of tungsten nickel cobalt matrix in which diamond and/or tungsten carbide inserts are provided. A signal is given to the surface that the blades are in their extended position by changing the mud.

Abstract: A method and apparatus for reaming foreign deposits from the flow passage of well production tubing and cleaning deposits from the completion profiles within the tubing as well as for drifting the production tubing while located within a well bore. A reaming tool is extended through the tubing string and is rotated for reaming operations. A plurality of reaming dogs of the tool are selectively and radially expanded to tubing and tubing completion profile reaming positions by cams of a hydraulically operated linearly removable actuator mandrel. The actuator mandrel is spring-urged toward a position permitting spring-urged retraction of the reaming dogs so that the reaming tool may be introduced into or withdrawn from the tubing string by linear movement.

Abstract: A casing mill for milling pipe cemented in an oil well comprises a body with a plurality of fixed milling blades having a diameter corresponding to the outside diameter of the pipe to be milled, and a second plurality of movable blades movable between a retracted position smaller than the inside diameter of the pipe to be milled, and an extended diameter corresponding to the outside diameter of a pipe coupling between adjacent sections of pipe. Means are provided for selectively moving the blades between the retracted and extended positions in response to drilling fluid flow. A stabilizer keeps the casing mill centered in the pipe to be milled. In this way, one can mill both the pipe and coupling in the vicinity of a coupling and mill only pipe between the vicinities of adjacent couplings.

Abstract: An apparatus for use in energy exploration is disclosed which is used where a radially expanding device is required, for example in a stabilizer, retriever or an underreamer. The apparatus comprises a support tubular member for connection to a drilling string, the member supporting a movable member which is axially movable along the member. A further member which may either be fixedly secured or also axially movable along the member is axially spaced from the movable member. The movable member and, optionally, the further member have tapered outer surfaces which cooperate with a taper on a radially movable member. The arrangement is such that movement of the movable member in the axial direction is such that the cooperating tapers cause the radially movable member to expand or contact in the radial direction. Various means for securing and performing radial movement are disclosed.

Abstract: An underreamer utilizes a plurality of cutting arms each having a plurality of tungsten carbide inserts, some of which have synthetic diamond cutting surfaces. There is a synthetic diamond gage cutter at the outer end of each cutting arm, and at least one other synthetic diamond cutter located more inwardly on the arm. The gage cutter is offset a greater distance from the leading side of the arm than are such other cutters. Recessed regions in front of the synthetic diamond cutters expose their full cutting faces while leaving steel for support of the cutters. Tungsten carbide inserts on the ends of the cutting arms between the leading side and the gage cutter minimize erosion of the steel arm and help prevent the gage cutter from being dislodged. The underreamer includes a hydraulic plunger for activating the cutting arms from a fully retracted to a fully deployed position, and a nozzle which ejects fluid toward the arm cutting surfaces during deployment and operation of the cutting arms.

Abstract: A drill having plural forwardly projecting circumferentially spaced cutting bits includes a hydraulic motor operated at full drilling fluid pressure to drive the cutting bits in unison through a first one-way clutch in a drilling mode. A centrifugal device responding to higher speed rotation of the drill operates a reversing valve connected with the hydraulic motor to reverse it at required times to incrementally advance the cutting bits of the drill in unison to compensate for wear and present a new sharp cutting face on each bit for continued drilling. The reversal of rotation of the bits is transmitted from the hydraulic motor through a second one-way clutch of the single revolution type which drives a pinion common to and in mesh with drive gears individual to the several cutting bits and matching the shapes of their flutes and being axially slidable relative thereto.