Abstract: A locking clutch to selectively transmit torque from a stator of a downhole tool to a rotor of the downhole tool includes at least one locking pawl radially between the rotor and the stator and configured to engage at least one recess formed in an outer periphery of the rotor, and a biasing mechanism configured to bias the at least one locking pawl into an engaged position. The at least one locking pawl includes a load path, two pivot axes, and a mass center. The at least one locking pawl transmits force from the stator to the rotor along the load path when in the engaged position, and centrifugal force urges the at least one locking pawl into a disengaged position when the rotor is rotated about one of the two pivot axes above a disengagement speed.

Abstract: A compact gas turbine motor and a speed reduction transmission capable of providing the speed and torque required for drilling with center discharge bits. The transmission includes two sun gears of different pitch diameters, keyed to the turbine shaft. Upper planet gears, whose carrier is fixed in place, drive an outer ring gear, which engages lower planet gears having a different pitch diameter. The lower planet gears engage the lower sun gear. Due to the different pitch diameters of the sun gears and planet gears, the gear carrier for the lower planet gears rotates in the same direction as the turbine shaft, but at a much slower rate. Exhaust gas from the turbine can be directed through one or more flow restriction elements to increase gas density in the turbine, further reducing turbine speed. The flow restriction element can comprise a venturi, to provide a vacuum assist to remove cuttings.

Abstract: This application is directed to a pressure balanced mud motor. The mud motor includes a power section to rotate a passageway housing and propel fluid through a passageway disposed in the passageway housing. The mud motor also includes a hydraulic apparatus for balancing a pressure drop experienced across a bearing assembly due to frictional flow of fluid through the passageway.

Abstract: The use in a drillstring of a positive displacement motor (PDM) with both an output upwardly and an output downwardly to devices spaced at least by the PDM.

Abstract: A percussion adapter that is driven to generate a percussive axial motion on a wellbore structure. One percussion adapter includes a drive connection to mechanically convert rotational drive to axially directed percussive motion. Another percussion adapter employs a valve that creates back pressure causing axially directed percussive motion. A wellbore tubular connection transitions torque to resist back off when left hand or right hand torque is applied.

Abstract: A down-hole drilling apparatus includes a bearing housing defining a longitudinal axis and upper and lower portions. The upper portion of the bearing housing is configured for connection to a drill string, and at least one annular bearing package disposed within the bearing housing. A drill bit is coupled to the bearing housing and rotatable with respect to the longitudinal axis. The drill bit includes a leading body supporting a plurality of cutters thereon for engaging a subterranean rock formation, a shank portion projecting from the leading body, and a mandrel portion engaging the shank portion and defining an inseparable connection therewith. The mandrel portion extends longitudinally into the bearing housing and through the at least one annular bearing package.

Abstract: A turbodrill using a balance drum. The turbodrill may include a housing having an upper end that is configured to be coupled to a drill string. The turbodrill may also include a rotatable shaft having a lower end configured to be coupled to a drill bit. The turbodrill may further include a balance drum assembly coupled to the shaft within the housing. In addition, the turbodrill may include a compliant mounting disposed between the balance drum assembly and the housing, where the compliant mounting is configured to allow displacement of the balance drum assembly within the housing.

Abstract: A downhole motor for drilling and servicing of wells has an elongated outer housing and an elongated mandrel rotatably disposed within the housing. A primary thrust bearing is disposed between the lower end of the housing and the mandrel, and transfers axial loads downward from the housing to the mandrel, and then to the drill bit or other tool mounted on the lowermost end of the mandrel. The placement of the primary thrust bearing permits it to extend radially to the outer diameter of the housing. One preferred embodiment of the primary thrust bearing comprises bearing surfaces of polycrystalline diamond compact (“PDC”) material.

Abstract: A motor and rotor catch assembly for preventing loss of broken motor parts downhole. The assembly comprises a motor including a rotor supported inside a stator housing. A rotor bolt is connected to the upper end of the rotor, and is supported for axial movement within a rotor bolt housing from a running position to a deployed position. If the stator housing breaks or backs off, the attached rotor bolt shifts to the deployed position. In the deployed position, the bolt substantially reduces flow to the stator housing and simultaneously opens bypass ports to vent fluid to the annulus instead. In this way, the rotor is prevented from spinning rapidly, the diverted fluid creates a pressure change that alerts the operator to the motor failure, and the diverted fluid allows continued removal of debris and cuttings from the well bore.

Abstract: A jet bit ensures precise drilling of holes through the earth's surface, such as drainholes around a well. The jet bit has front rotating orifices and jets to drill a hole in a medium larger than the diameter of the bit. The orifices directed to the rear provide thrust to propel the bit forward by enlarging the drainhole. A stationary shroud extends beyond the front orifices to maintain the front jets rotation. The jet bit may include turbine to control rotation rate and torque on front jets containing rotating shafts. A jet bit can be small enough to turn in a radius of four (4) inches from a vertical wellbore to create a horizontal drainhole. Various mechanical cutters can be mounted on the front of the jet bit to enable cutting with both jets and mechanical cutters.

Abstract: A coated component for use in a fluid energy device includes a coating system with multiple layers of coating material, including a soft material such as a polymer coated over a hard material such as a metal. The fluid energy device can be a fluid motor or fluid pump, and the coated component can be a rotor or a stator. The hard and soft materials may be interlocked with each other and/or with an interposed porous layer. The presence of the soft material can reduce or eliminate the need for meticulous polishing operations typically required with as-applied hard materials while improving the longevity of mating fluid energy device components. The mating components are exposed only to the soft material in the initial stages of operation, after which the soft material wears away to gradually expose the mating components to the hard material in a less abrasive manner.

Abstract: A valve (11) for controlling the flow of a drilling fluid through a down-hole tool (10) positionable in a wellbore penetrating a subterranean formation. The down-hole tool has a housing with a drilling motor therein and a drill bit (1) at an end thereof. The drilling motor (9) has a housing with a rotor (206) rotationally movable in a rotor channel (204) as the drilling fluid passes through a rotor channel between the housing and the rotor. The rotor has a bypass channel therethrough for bypassing a portion of the drilling fluid therethrough. The valve includes a valve plate positionable upstream of the motor. The valve plate (200) has at least one flow passage (226) and at least one bypass passage (220) therethrough. The flow passage is in fluid communication with the rotor channel for passing the drilling fluid therethrough.

Abstract: A drilling machine includes a compressor coupled to a prime mover through a hydraulic clutch, wherein the hydraulic clutch is repeatably moveable between engaged and disengaged conditions. The compressor is allowed to provide air and is restricted from providing air in response to the hydraulic clutch being in the engaged and disengaged conditions, respectively. The hydraulic clutch is moveable between the engaged and disengaged conditions during operation of the prime mover.

Abstract: A dynamic steering tool for use with a horizontal directional drilling machine. The tool comprises and inner member, an outer member, a steering member, a drill stem, and a drill bit. The drill stem extends from within a borehole to the surface while the outer member only extends the length of the inner member within the borehole. The outer member is powered via the use of a progressive cavity motor. In operation, the drill stem, inner member, and drill bit rotate in a clockwise position while the outer member rotates in a counterclockwise direction. Rotating the outer member opposite the inner member allows the outer member to remain stationary and cause the tool to steer while the inner member continues to rotate.

Abstract: The present invention relates to a downhole driving unit (11) for insertion into a well, comprising a driving unit housing (51), a hydraulic motor (23) comprising a hydraulic motor housing (93), a wheel assembly (90) comprising a stationary part (91) and a rotational part (92), the stationary part being connected with the driving unit housing and being rotatably connected with a rotational part, the wheel assembly comprising a wheel ring (99) for contacting an inner wall in the well and connected with or forming part of the rotations part. The wheel assembly further comprises the hydraullic motor (23) so that the stationary part and the rotational part constitute the hydraulic motor housing, the hydraulic motor comprising a rotatable section (84) connected with the rotational part for rotating part of the wheel assembly.

Abstract: The present invention relates to a downhole driving unit (11) for insertion into a well, comprising a driving unit housing (51), a hydraulic motor (23) comprising a hydraulic motor housing (93), a wheel assembly (90) comprising a stationary part (91) and a rotational part (92), the stationary part being connected with the driving unit housing and being rotatably connected with the rotational part, the stationary part and the rotational part constituting the hydraulic motor housing, the rotational part comprising a wheel ring (99) closed from one end, wherein the wheel assembly comprises a spring member (113) assembling the hydraulic motor housing.

Abstract: The present invention relates to a downhole driving unit (11) for insertion into a well, comprising a driving unit housing (51), a hydraulic motor comprising a hydraulic motor housing (93), the hydraulic motor comprising a cam ring (24), a wheel assembly (90) comprising a stationary part (91) and a rotational part, the stationary part (92) being connected with the driving unit housing and a rotatably connected with a rotational part, the stationary part and the rotational part constituting the hydraulic motor housing, said hydraulic motor comprising a rotatable section (84) connected with the rotational part, the cam ring being connected with or forming part of the stationary part of the wheel assembly, the rotational part comprising a wheel ring (99), where in a bearing (36) is arranged between the cam ring and the wheel ring. The present invention also relates to a downhole system comprising the driving unit and to use of such driving unit.

Abstract: The present invention relates to a downhole driving unit (11) (for insertion into a well, comprising a driving unit housing (51), an arm assembly (60) movable between a retracted position and a projecting position in relation to the driving unit housing, an arm activation assembly (41) arranged in the driving unit housing for moving the arm assembly between the retracted position and the projecting position and a wheel assembly (90) comprising a stationary part (91) and a rotational part (92), the stationary part being connected with or forming part of the arm assembly and being rotatably connected with a rotational part. The wheel assembly comprises a hydraulic motor comprising a hydraulic motor housing (93) and a rotatable section (84) connected with the rotational part for rotating part of the wheel assembly. Furthermore, the present invention relates to a downhole system comprising said driving unit and to use of such driving unit.

Abstract: There is provided for laser bottom hole assembly for providing a high power laser beam having greater than 5 kW of power for a laser mechanical drilling process to advance a borehole. This assembly utilizes a reverse Moineau motor type power section and provides a self-regulating system that addresses fluid flows relating to motive force, cooling and removal of cuttings.

Abstract: Various embodiments relate to bearing assemblies configured to enable removal and replacement of superhard bearing elements, and bearing apparatuses that may utilize such bearing assemblies. The disclosed bearing assemblies may be used in a number of applications, such as downhole motors in subterranean drilling systems, directional drilling systems, roller-cone drill bits, and many other applications. In an embodiment, a bearing assembly includes a support ring and a retention ring assembled with the support ring. The bearing assembly further includes a plurality of superhard bearing elements. The retention ring and at least a number of the superhard bearing element are collectively configured to restrict displacement of the at least a number of the superhard bearing elements.

Abstract: A downhole tool includes a tool body, stator, and rotor. The tool body is aligned along a tool centerline and includes an aperture therethrough operable to pass a fluid to an exterior of the body. The stator is fixed relative to the tool body and includes a fluid flow restriction operable to pass at least a portion of the fluid from an interior of the stator to the exterior of the body at an adjustable flow rate. The rotor is disposed within the tool body and rotatable relative to the stator and includes an exhaust port selectively aligned with at least one aperture through the tool body by rotation of the rotor relative to the stator. The exhaust port is operable to pass at least a portion of the fluid from an interior of the rotor to the exterior of the body when aligned with the aperture.

Abstract: A turbine drill motor capable of operation at ultra-high rotary speeds (i.e., in excess of 1000 rpm, which is very high for turbine drill motors), with a high-pressure jet-assist functionality for drilling and well service applications. The ultra-high rotary speed enables fast penetration with diamond bits, while the high-pressure jet-assist ensures adequate cooling and cuttings removal. In an exemplary embodiment, such a turbine drill motor includes a bypass channel to divert a portion of the driving fluid supply when the bit is off-bottom, to limit the no-load runaway speed of the turbine. Serial and parallel flow paths can be accommodated, and different drill bits for cutting and well-bore servicing are disclosed.

Abstract: A compact gas turbine motor and a speed reduction transmission capable of providing the speed and torque required for drilling with center discharge bits. The transmission includes two sun gears of different pitch diameters, keyed to the turbine shaft. Upper planet gears, whose carrier is fixed in place, drive an outer ring gear, which engages lower planet gears having a different pitch diameter. The lower planet gears engage the lower sun gear. Due to the different pitch diameters of the sun gears and planet gears, the gear carrier for the lower planet gears rotates in the same direction as the turbine shaft, but at a much slower rate. Exhaust gas from the turbine can be directed through one or more flow restriction elements to increase gas density in the turbine, further reducing turbine speed. The flow restriction element can comprise a venturi, to provide a vacuum assist to remove cuttings.

Abstract: A bottom hole assembly has a drill bit that is driven by a downhole turbine. The turbine speed is reduced by cycloidal gearing that requires no temperature sensitive seals when operating temperatures in some applications exceed 350 degrees F. The output shaft of the cycloidal gear reducer goes through a bearing before connection to the drill bit or associated reamer. The motive fluid can be the drilling mud. The bit can be driven at desired speeds such as 50-300 RPM while the speed reduction ratio can be in the order of 10 to 1 or more. This drive assembly can replace Moineau type downhole motor drivers that have temperature limitations due to use of rubber in the stators.

Abstract: Bearing assemblies and apparatuses are disclosed. Such bearing assemblies may be employed in bearing apparatuses for use in downhole motors of a subterranean drilling system or other mechanical systems. In an embodiment of the present invention, a bearing apparatus includes a first bearing assembly including a first substantially continuous polycrystalline diamond bearing surface defining an annular surface, and a second bearing assembly including a second substantially continuous polycrystalline diamond bearing surface defining an annular surface. The second substantially continuous polycrystalline diamond bearing surface generally opposes the first substantially continuous polycrystalline diamond bearing surface.

Abstract: Rotational locking mechanisms for drill string assemblies, bottom hole assemblies, and drilling motors are presented herein. A fluid-driven motor assembly is disclosed for use in a drill string to drill a borehole in an earth formation. The drill string includes a drill pipe and a drill bit. The motor assembly includes a housing that is configured to operatively connect to the drill pipe of the drill string to receive drilling fluid therefrom. A stator, which is disposed within the housing, is configured to rotate at a stator speed. A rotor is disposed within the stator and coupled to the drill bit. The rotor is configured to rotate at a rotor speed. The motor assembly also includes a rotational locking assembly operatively coupled to the rotor and the housing. The rotational locking assembly is configured to prevent the stator speed of the stator from exceeding the rotor speed of the rotor.

Abstract: An apparatus for cutting a wellbore includes a motor having a stator and a rotor. The rotor has an output shaft connected to a cutting structure. The stator and rotor are spaced radially outwardly of the axis of rotation of the rotor such that at least one of the stator and the rotor had an access bore extending through the motor to adjacent the cutting structure. A further object can pass therethrough, without obstruction. The further object comprises a further cutting. A flow diverter is disposed in the motor proximate a connection between the motor and a wellbore tubular, and has a first fluid outlet in fluid communication with a power section of the motor, and a second fluid outlet in fluid communication with the access bore. The flow diverter is coupled to the stator such that axial loading created by fluid pressure is substantially transferred to the stator.

Abstract: A gas turbodrill with an adjustable bent housing for use in a spur lateral drilling application. The gas turbodrill includes a high-speed gas turbine, a gearbox assembly, a pivoting shaft connection point, a gimbal assembly comprising a hollow ball and socket joint, a bearing assembly and drill bit assembly. The gas turbodrill gimbal assembly enabling a bend through an angle of up to 5 degrees while drilling. Springs and the application of pressure will lock the bend in place once drilling commences to facilitate lateral drilling of the spur.

Abstract: Device for lining the wall of a wellbore as it is being drilled using a drill string having a drill bit on the lower end thereof. The device has a receptacle for a cylindrically gathered pack of flexible tubing capable of being supported around the outside of the drill string near the lower end thereof on a plurality of bearings, a radially expandable locking device attachable to one end of the flexible tubing and being capable of being expanded against the wellbore wall to lock the end of the flexible tubing in place in the wellbore, and a conduit having an inlet upstream of the receptacle and an outlet downstream of the receptacle. A pump is located in the conduit or abutting the inlet or outlet thereof, and pumps the drilling fluid so that a fluid pressure inside the liner is greater than a fluid pressure at the drill bit.

Abstract: A downhole positive displacement motor converts hydraulic fluid pressure into rotational torque. The motor includes a non-helical rotor and stator, and upper and lower valve assemblies each comprising cylindrical rotating and stationary elements which define longitudinal passages. The timing of alignment of the passages creates pressure in power pockets in the stator, rotating the rotor. The rotational torque can be used in any application that may require mechanical force to operate or drive a mechanism created for oil, gas, or water production in a down hole application.

Abstract: A bottom hole assembly for a drill string has a mud motor and a mandrel. The motor has a rotor and a stator, and the rotor defines a bore for passage of conductors. The mandrel has a bore for passage of the conductors and for drilling fluid, and rotation of the mandrel rotates a drill bit. A shaft and universal joints covert orbital motion at the rotor to rotational motion at the mandrel. To pass the conductors from a sonde uphole of the motor to electronics disposed with the mandrel, an inner beam disposes in a bore of the shaft. This inner beam has an internal passage for the conductors, and seal caps dispose on each end of the inner beam to seal inside the universal joints. The inner beam and seal caps prevent drilling fluid passing from the motor and around the shaft from communicating in the shaft's bore.

Abstract: A down hole drilling tool for preventing overpressure strain on surface pumping equipment or a down hole drilling motor having a housing and a circulation port and four hydraulic valves positioned on the housing actively working together to affectively open the circulation port to drilling annulus at a high pressure setting and dose the circulation port to annulus at a low pressure setting, the four hydraulic valves include a high pressure setting valve, a low pressure setting valve, a control valve and a fixed setting valve.

Abstract: Various embodiments relate to bearing assemblies configured to enable removal and replacement of superhard bearing elements, and bearing apparatuses that may utilize such bearing assemblies. The disclosed bearing assemblies may be used in a number of applications, such as downhole motors in subterranean drilling systems, directional drilling systems, roller-cone drill bits, and many other applications. In an embodiment, a bearing assembly includes a support ring and a retention ring assembled with the support ring. The retention ring includes a plurality of through holes. The bearing assembly further includes a plurality of superhard bearing elements, with each superhard bearing element inserted partially through and projecting from a corresponding one of the through holes of the retention ring. The retention ring and each superhard bearing element are collectively configured to restrict displacement of each superhard bearing element beyond a selected position in a direction away from the support ring.

Abstract: A reaming bit designed to operate with low torque fluctuation when driven with a turbine at speeds in the order of 300-600 RPM and above features a profile that is arcuate from the gauge dimension to the nose area or alternatively has a blunt straight taper section but with a ratio of profile length (PL) to bit size (BS) of under 0.75. The blades extend into a concave cone and the cutting structure continues along the blades towards the center. The blades have a step near the gauge section to increase the exposure of the blade cutting structure. An array of protrusions are disposed parallel to and behind the cutting structure to increase high speed stability and adjacent the blade step transition to protect outer casing on run in.

Abstract: A system and methodology provide valves, bottom hole assemblies, and methods of selectively actuating a motor. One aspect provides a valve including: a barrel having an interior having a circular cross-section, an inlet port, an outlet port, and a by-pass port; a first disc rotatably received within the barrel; and a second disc rotatably received within the barrel and pressed against the first disc to selectively form a seal. The first disc and the second each have an orifice.

Abstract: Methods and systems for storing kinetic energy in a fluid-base power circuit. A regenerative control valve manifold diverts fluid flow from a hydraulic device performing a first operation into an accumulator. The accumulator stores a fluid volume sufficient to perform a second operation. The regenerative control valve manifold connects the accumulator to the power circuit providing a fluid flow and charge pressure sufficient to perform the second operation.

Abstract: A down hole apparatus for generating a pulsing action includes a tubular housing a rotating first mandrel with a first cam profile and a reciprocating second mandrel with a second cam profile, which engages the first cam profile. Upon rotational movement of the first mandrel, the first cam profile exerts an axial force upon the second cam profile to initiate a pulsing action by forcing the second mandrel away from the first mandrel. Springs bias the second mandrel back toward the first mandrel, thereby completing the pulsing action and maintaining the second cam profile engaged with the first cam profile.

Abstract: The present invention discloses a cutting tool integrated in a drillstring for enlarging a borehole, where the cutting tool at least comprises: one or more side mills (12, 13, 14) arranged along the axis of said drillstring in a reamer housing (11), where the side mills (12, 13,14) are adapted to be rotated relative to the tool housing (11) by individual driving means. The self driven rotational side mills may be dome shaped cones where expand radially out of the reamer housing (11), or may be a special non-circular dome shaped cones where rotates without expanding.

Abstract: A downhole motor for drilling and servicing of wells has an elongated outer housing and an elongated mandrel rotatably disposed within the housing. A primary thrust bearing is disposed between the lower end of the housing and the mandrel, and transfers axial loads downward from the housing to the mandrel, and thence to the drill bit or other tool mounted on the lowermost end of the mandrel. The placement of the primary thrust bearing permits it to extend radially to the outer diameter of the housing. One preferred embodiment of the primary thrust bearing comprises bearing surfaces of polycrystalline diamond compact (“PDC”) material.

Abstract: In one aspect of the present invention, a downhole drill string assembly comprises a bore there through to receive drilling fluid. A turbine may be disposed within the bore and exposed to the drilling fluid. At least one flow guide may be disposed within the bore and exposed to the drilling fluid wherein the flow guide acts to redirect the flow of the drilling fluid across the turbine. The flow guide may be adjusted by an actuator. Adjustments to the flow guide may be controlled by a downhole telemetry system, a processing unit, a control loop, or any combination thereof. In various embodiments the turbine may comprise rotatable turbine blades.

Abstract: A technique provides a drilling system and method in which a drilling assembly is delivered downhole on coiled tubing. The drilling assembly comprises a drill bit and a motor to rotate the drill bit for drilling of a borehole. A steerable system is used to steer the drill bit, thereby enabling formation of deviated boreholes.

Abstract: A turbine for use in a downhole drill string including an elongated casing defining an interior and a plurality of motor units in the interior. Each motor unit has a rotor and a stator. A torque transmission couplings connects each of the plurality of motor units to the drill string. The torque transmission couplings having flexible linkages. As a result, the power section has tight tolerances for the clearance at the tips of the rotors because the motor units are relatively stiff. The flexing normally obtained by bending the rotor shaft is accomplished and absorbed in the flexible linkages.

Abstract: A system and method are disclosed for drilling a well and obtaining a downhole core sample. A drilling rig includes a pivotal mast. The mast supports an injector thereon with an injector axis offset with respect to the central axis of the mast when the drilling rig is handling threaded tubular. The mast also supports a drive unit. A drilling assembly includes coil tubing, the injector, and a bottomhole assembly including a percussion tool suspended in the well from the coil tubing. A coring assembly includes a threaded tubular string and the drive unit supported on the mast for rotating the threaded string and the coring bottomhole assembly while the injector is spaced from the axis of the mast.

Abstract: A pulsing tool for use with a tubular string having a motor unit and a pulsing unit coupled to the motor unit. In one embodiment, the pulsing unit includes a mandrel having an inlet opening and an outlet opening and a flow control bushing, wherein rotation of the mandrel relative to the flow control bushing creates a pressure oscillation which causes movement of the tubular string.

Abstract: A moving cavity motor or pump, such as a mud motor, comprising: a rotor, a stator, and one or more apparatus for constraining (i.e., controlling or limiting) the movement of the rotor relative to the stator.

Abstract: A bottom-hole assembly for directional drilling incorporates a torque generator with a drive shaft connected to a drill string. The torque generator generates a torque that counters a reactive torque when a drill bit of the bottom-hole assembly is driven. When the drill string is rotated at a static drive speed, a drill tool face of the bottom-hole assembly is stabilized to drill a nonlinear bore segment. When the drill string is rotated at a rotational speed other than the static drive speed the bottom-hole assembly is rotated to drill a linear bore segment.

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

Abstract: A 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: In one aspect of the invention, 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: In aspects, the disclosure provides a drilling motor that includes a lubricating unit that selectively supplies a lubricant to the drilling fluid before the drilling fluid passes through the drilling motor so as to lubricate the stator and/or the rotor to reduce friction between the stator and the rotor and to reduce wear of the motor.