Abstract: A boring bit such as for horizontal directional drilling is provided which includes a hard faced layer that is preferably made by a laser cladding bead. The laser clad bead may be applied in some regions to a greater extent and in other regions to a lighter extent and with thicker coverage or longer regions of application in different regions of the boring bit. Additionally, circumferential segments of the hard faced layer bead may be applied to impart a spiral path on the outer periphery of the boring bit which may be overlapped upon more general hard faced layer application. Further, the hard faced layer may be applied in substantially complete coverage over carbide insert teeth that are embedded within the steel base of the boring bit body.

Abstract: A tubular member includes a central axis, a first end, a second end opposite the first end, and a throughbore extending axially from the first end to the second end. In addition, the tubular member includes a first connector at the first end and a second connector at the second end. Further, the tubular member includes a tubular region axially positioned between and axially spaced from the first connector and the second connector. The tubular member also includes a first upset axially positioned between the tubular region and the first connector. The first upset has an internal transition within the throughbore that increases an inner diameter of the throughbore when moving axially from the first upset to the tubular region. Moreover, the tubular member includes a first wear pad integrally formed on the tubular region. An outer diameter of the tubular member is greater along the first wear pad than along the tubular region.

Abstract: A downhole motor for directional drilling includes a driveshaft assembly including a driveshaft housing and a driveshaft rotatably disposed within the driveshaft housing, a bearing assembly including a bearing housing and a bearing mandrel rotatably disposed within the bearing housing, wherein the bearing mandrel is configured to couple with a drill bit, a bend adjustment assembly configured to adjust a bend setting of the downhole motor, a lock piston including an unlocked position, and a locked position configured to lock the bend setting of the bend adjustment assembly, one or more hydraulic pumps configured to actuate the lock piston into the unlocked position to unlock the bend adjustment assembly, and an electronics package configured to indicate the bend setting of the bend adjustment assembly.

Abstract: A crusher includes a housing having an inlet and an outlet at opposite axial sides, an impeller positioned proximate the inlet of the housing, and a shaft connected to the impeller and extending axially through the housing between the inlet and the outlet. At least two spaced apart support structures hold the shaft in the housing, where a plurality of dynamic blades extending outwardly from the shaft are alternatingly positioned between a plurality of fixed blades extending radially inward from an inner wall of the housing.

Abstract: A tool that removes a scale inside a pipe includes: a laser tool including a laser head to output a laser beam, and a robotic arm that is articulated and that is connected to the laser head. The robotic arm includes segments that are connected by flexible robotic arm joints to enable movement of the laser head in six degrees of freedom, and a control system to control the robotic arm to direct output of the laser beam. The tool also includes a drilling shaft attached to the robotic arm of the laser tool.

Abstract: A system has a fin with an upstream end, a downstream end, a wall interface (412), a carrier interface (414) offset from the wall interface (412) in a radially inward direction, and an impact surface (418). The impact surface extends between an upstream end of the wall interface and an upstream end of the carrier interface. The impact surface (418) has a substantially flat portion configured to cause flow stagnation. The fin (306) has a side surface (416) extending between the impact surface (418), the wall interface (412), and the carrier interface. The impact surface (418) is joined to the side surface (416) by an edge profile (420) configured to cause turbulence or separation of the fluid flow from the fin.

Abstract: A downhole assembly includes a bit and a cutting tool uphole of the bit. The cutting tool has one or more expandable cutter arms. The one or more expandable cutter arms include at least one stabilizer portion having a radial position that is about the same as a gauge of the bit when the one or more expandable cutter arms are in an expanded position. A spline on the cutter arms are used by a cutting tool to move the cutter arms.

Abstract: Centralizers for stabilizing production tubing within a well may include a mandrel for securing within a section of production tubing and having a gland mounting surface; a gland mounted to the gland mounting surface of the mandrel, and having a cylindrical body and two or more lobes extending radially outward from the cylindrical body and comprised of an abrasion resistant material. Downhole assemblies may include a production string receivable within a cased well; a tubing anchor catcher positioned within the production string; a downhole pump coupled to the production string and located axially below the tubing anchor catcher; and a centralizer coupled to the production string.

Abstract: A downhole motor for directional drilling includes a driveshaft assembly including a driveshaft housing and a driveshaft rotatably disposed within the driveshaft housing, a bearing assembly including a bearing housing and a bearing mandrel rotatably disposed within the bearing housing, wherein the bearing mandrel is configured to couple with a drill bit, a bend adjustment assembly including a first position that provides a first deflection angle between a longitudinal axis of the driveshaft housing and a longitudinal axis of the bearing mandrel, and a second position that provides a second deflection angle between the longitudinal axis of the driveshaft housing and the longitudinal axis of the bearing mandrel that is different from the first deflection angle, and one or more hydraulic pumps configured to actuate the bend adjustment assembly between the first position and the second position.

Abstract: A new system for and a method of deploying a heat exchanger pipe. A bore hole is drilled from an access ditch location to a terminal ditch location using a piloted drill head powered via an umbilical attached to the piloted drill head. A casing is attached to the piloted drill head and disposed about the umbilical into the bore hole from the access ditch location to the terminal ditch location. At the terminal ditch location, the piloted drill head is removed from the casing and the umbilical and a heat exchanger pipe is attached to the umbilical. The umbilical is withdrawn from within the casing deployed in the bore hole to pull the heat exchanger pipe into the casing. The casing is then withdrawn from the bore hole leaving the heat exchanger pipe in the bore hole.

Abstract: A bottom hole assembly (BHA) includes a whipstock having a latch release mechanism and a milling tool having a plurality of blades and a lock mechanism. The BHA also includes a collar coupled to the whipstock and disposed about a portion of the milling tool, wherein the blades of the milling tool abut the collar. The milling tool is releasably coupled to the whipstock by the interaction of the latch release mechanism and the lock mechanism.

Abstract: Apparatus and methods for controlling release of torsional energy from a drill string having a lower portion that is stuck against a subterranean formation and a top end rotated by a top drive. The method may include decreasing a rotational speed set-point of the top drive, decreasing a torque set-point of the top drive, and/or decreasing flow rate of drilling mud being pumped downhole via the drill string, thereby decreasing torque output by a mud motor rotating a drill bit. The method may further include lifting the drill string to free the drill string. Decreasing the torque set-point of the top drive may comprise decreasing the torque set-point of the top drive to a minimum torque level that the top drive can output. Decreasing the rotational speed set-point of the top drive may comprise decreasing the rotational speed set-point of the top drive to zero.

Abstract: A seamless steel pipe is provided that has a chemical composition which consists of, by mass %, C: 0.10 to 0.20%, Si: 0.05 to 1.0%, Mn: 0.05 to 1.2%, P?0.025%, S?0.005%, Cu?0.20%, N?0.007%, Ni: 0.20 to 0.50%, Cr: 0.30% or more and less than 0.50%, Mo: 0.30 to 0.50%, Nb: 0.01 to 0.05%, Al: 0.001 to 0.10%, B: 0.0005 to 0.0020%, Ti: 0.003 to 0.050%, V: 0.01 to 0.20%, a total of any one or more elements among Ca, Mg and REM: 0 to 0.025%, and the balance: Fe and impurities, and for which Pcm (=C+(Si/30)+(Mn/20)+(Cu/20)+(Ni/60)+(Cr/20)+(Mo/15)+(V/10)+5B)?0.30. The steel micro-structure includes, in area %, tempered martensite ?90%. The tensile strength is 980 MPa or more, and a Charpy impact value at ?40° C. using a 2 mm V-notch test specimen is 75 J/cm2 or more.

Abstract: A method includes extending a wellbore using a drill bit that forms a portion of a bottom hole assembly; enlarging a diameter of the wellbore using a reamer of the assembly; and laterally offsetting either a rotary steerable tool or a mud motor of the assembly in the enlarged diameter wellbore. A bend angle is defined between a central axis of either the rotary steerable tool or the mud motor creates and a central axis of the drill bit. Enlarging the diameter of the wellbore using the reamer while steering the assembly decreases the dogleg. Enlarging the diameter of the wellbore using the reamer while rotational drilling a straight section of the wellbore reduces stresses on the assembly and reduces wellbore tortuosity.

Abstract: A system for downhole wellbore vector strain sensing including a strain sensor positionable between an outer surface of a wellbore casing and a subterranean formation for sensing a plurality of strain tensor elements, the plurality of strain tensor elements comprising multiple components of a strain tensor; a computing device positionable at a surface of a wellbore and communicatively coupled to the strain sensor; and a communication link between the strain sensor and the computing device for communicatively coupling the strain sensor to the computing device to relay strain data, the strain data comprising the plurality of strain tensor elements.

Abstract: Systems and methods to cover sensitive areas of downhole tools including a downhole tool having an outer surface including a first position and a second position on the outer surface of the downhole tool, the outer surface having a sensitive area, a downhole sensitive element positioned along the outer surface of the downhole tool at the sensitive area, a movable cover operatively connected to the downhole tool and movable relative to the sensitive area, a control unit configured to generate an activation signal, and an activation mechanism operable in response to the activation signal, the activation mechanism configured to move the movable cover relative to the sensitive area from the first position to the second position, wherein the movement of the movable cover from the first position to the second position one of increases or decreases a portion of the sensitive area covered by the movable cover.

Abstract: In a case where passivity-based control is applied to a plurality of circuits connected in parallel, a simpler target state is used. A switching power supply system includes: a plurality of switching power supply circuits connected in parallel to a load R; and a controller configured to switch each of the plurality of switching power supply circuits, through passivity-based control, by using a sum of currents that flow in the plurality of switching power supply circuits.

Abstract: A drilling tool includes a pilot bit coupled to an eccentric reamer that has a reaming side and a stabilizing side. A fluid passageway extends between the reamer and the pilot bit, and the tool includes at least one upwardly-directed nozzle in fluid communication with the fluid passageway and positioned on the stabilizing side of the reamer. The reamer may include a plurality of angularly spaced blades on the reaming side that radially extend a first distance, the reamer blades being disposed within a first arcuate segment defined by the two most distant reamer blades. One or more stabilizing blades extend a second distance that is less than the first distance, the stabilization blades being disposed within a second arcuate segment defined by the two most distant reamer blades and that has the angular measure equal to 360 degrees minus the first arcuate segment.

Abstract: Modular stabilizer tools may be used to reduce unwanted deflection of a wellbore and in effecting a desired change in direction of a wellbore in an efficient and inexpensive manner. As the diameter of a wellbore changes, the modular stabilizers plates may be configured to expand or decrease the outer diameter of a modular stabilizer tool without requiring removal of an entire section of the drill string. Each modular stabilizer plate of a modular stabilizer tool may be configured to align and affix to any one or more other modular stabilizer plates and may be of any size or shape. A site need only maintain a small inventory of modular stabilizer plates instead of entire collars, tools, or sections of a drill string. When any modular stabilizer plate, especially an outer spacer stabilizer plate, experiences wear or damage, it may be replaced without the requirement of replacing an entire collar.

Abstract: The present invention relates to a stabilizing system (100, 200, 300) adapted to be used in a drilling system, wherein the transversal diameter of the stabilizing system (100, 200, 300) increases when drilling forces are applied onto the stabilizing system (100, 200, 300). The invention further comprises a corresponding method for drilling a hole.

Abstract: An apparatus and method for reducing torque in a drill string, in which the apparatus includes a first clamp assembly including a plurality of arcuate clamp segments that are pivotally connected together, the plurality of arcuate clamp segments being configured to be positioned around and secured to an oilfield tubular so as to be rotationally fixed to the oilfield tubular, and an outer sleeve positioned around the first clamp assembly. The outer sleeve includes at least two sleeve segments assembled together to form a generally cylindrical sleeve around the first clamp assembly, and the first clamp assembly is configured to rotate with the oilfield tubular and with respect to the outer sleeve.

Abstract: The invention relates to reamers used in downhole oil well operations, particularly in reaming while drilling applications. Presented is a reamer having an interior channel which runs axisymmetric to an elongate axis of the entire body of the reamer, wherein there are openings along both ends of the reamer, exposing the interior channel. Additionally presented in the reamer are a plurality of paths extending parallel to the interior channel along the exterior of the body of the reamer, and running in a helical pattern along the entirety of the exterior of the body of the reamer. Disposed within the helical paths are a plurality of cutting inserts, which cutting inserts are enabled to provide a uniform cutting surface against a well bore, which preferably improves cutting action and reduces strain on the reamer.

Abstract: An apparatus disposed on a drillstring deviates a borehole advanced by a drill bit. At least one director is disposed on a housing to rotate therewith. The director at least includes a piston movable in a chamber, a pad pivotable about a pivot point between an extended condition and a retracted condition relative to the housing, and a linkage arm pivotably connected between the piston and the pad. At least one actuator disposed on the housing in fluid communication with a housing bore is operable at least between a first condition (directing communicated fluid from the bore or other source to the chamber of the director) and a second condition (at least permitting the director to retract toward the retracted condition).

Abstract: Systems and methods for long term disposal of high level nuclear waste in deep geologic formations are described. Such systems and method may include largely intact spent nuclear fuel rods in a disassembled form that may be placed into waste-capsules (e.g., carrier tubes); which may then be placed into various well boreholes. Example embodiments may provide waste-capsules capable of containing and disposing of waste generated from spent nuclear fuel, including means for harvesting the nuclear waste from cooling pools and operationally processing the waste fuel assemblies for inclusion in the waste-capsules with various engineered barriers; along with storage in horizontal well boreholes drilled into closed deep geologic formations.

Abstract: A drilling string stabilizer tool comprises a cylindrical body and a plurality of stabilizer blades machined as an integral component forming in this way a monolithic blade stabilizer tool. The stabilizer blades have an elongated shape and are aligned in the direction of the axis of the cylindrical body. The blades are disposed in such a way to result in an almost constant flow-by-area.

Abstract: Drilling dysfunction during simultaneous down-hole drilling and reaming is reduced by obtaining an indication of force on cutters of a reamer, determining whether or not the indication indicates an excessive force, and upon determining that the indication indicates an excessive force, extending drag elements from the bottom hole assembly to contact a wall of the well bore and reduce the force on the cutters of the reamer. The indication of force on the cutters can be obtained by sensing the weight on the drill bit, and the determination can be done by comparing the indicated weight on the drill bit to a first threshold and a second threshold.

Abstract: A bend adjustment assembly for a downhole mud motor includes a driveshaft housing, a driveshaft disposed in the driveshaft housing, a bearing mandrel, wherein the bend adjustment assembly includes a first position that provides a first deflection angle between a longitudinal axis of the driveshaft housing and a longitudinal axis of the bearing mandrel, wherein the bend adjustment assembly includes a second position that provides a second deflection angle between the longitudinal axis of the driveshaft housing and the longitudinal axis of the bearing mandrel, and an actuator assembly configured to shift the bend adjustment assembly between the first position and the second position in response to a change in at least one of flowrate of a drilling fluid supplied to the downhole mud motor, pressure of the drilling fluid supplied to the downhole mud motor, and relative rotation between the driveshaft housing and the bearing mandrel.

Abstract: Stabilizer-reamer for drilling string characterized in that it comprises a mixture of diamond impregnated inserts, the mixture comprising cutting diamond impregnated inserts and wear resistant diamond impregnated inserts, said wear resistant diamond impregnated inserts having smaller diamond grain size and higher diamond concentration than said cutting diamond impregnated inserts.

Abstract: A sucker rod includes end fittings comprising a frustoconical insert which is threaded onto a threaded rod and a sleeve with a frustoconical internal surface which encircles the insert. Tension on the end fittings wedge the frustoconical insert in the sleeve. A connector having threads for engaging an end fitting of a second sucker rod is screwed into the sleeve.

Abstract: A mud motor for use in a wellbore includes: a stator; a rotor, the stator and rotor operable to rotate the rotor in response to fluid pumped between the rotor and the stator; and a lock. The lock is operable to: rotationally couple the rotor to the stator in a locked position, receive an instruction signal from the surface, release the rotor in an unlocked position, and actuate from the locked position to the unlocked position in response to receiving the instruction signal.

Abstract: A turbine-drill bit assembly is disclosed. The assembly comprises a box connection turbine connected to a pin connection drill bit. The turbine has a turbine body around a turbine shaft, the turbine body having a turbine stabilizer. The drill bit has a bit gauge or a bit sleeve around a bit shank, an end of the turbine stabilizer nearest the drill bit being spaced a first maximum distance from an end of the bit gauge or bit sleeve. In addition, a shouldering interface is formed at respective abutment shouldering surfaces of the turbine shaft and bit shank when the drill bit is attached to the turbine shaft, the interface being spaced a second maximum distance from an end of the bit gauge or bit sleeve.

Abstract: A pipe to be placed within a well for producing a fluid of interest includes an outer face onto which is crimped a tubular metal element. The inner face of the tubular element exhibits an annular groove in which a metal anchoring ring or a pair of juxtaposed anchoring rings is engaged. Each anchoring ring consists of a ring split transversely at least partially, is provided on its inner face with projecting anchoring members, and exhibits, in cross-section, a base equipped with the projecting members and at least one flank forming an acute angle with the base. The annular groove exhibits a profile that is substantially complementary to that of the ring(s). The depth of the groove is less than the thickness of the ring or of the rings. The projecting members are at least partially embedded into the pipe after crimping of the metal element onto the pipe.

Abstract: A method of making a combination tool including a mining drill bit and reamer. The combination tool includes drill bit body having a plurality of cutting segments attached thereto, a reamer body having a plurality of reaming segments attached thereto, and the drill bit body and the reamer body being configured to selectively attach to the one another. The cutting segments and reamer segments being attached by laser welding to the drill bit body and reamer body, respectively.

Abstract: Rotary drag bits comprise a body comprising a face at a leading end of the body. An abrasive-impregnated cutting structure is located at the face of the body. The abrasive-impregnated cutting structure comprises abrasive particles dispersed within a matrix material. The abrasive-impregnated cutting structure exhibits an anisotropic wear resistance. The wear resistance varies at least substantially continuously within the abrasive-impregnated cutting structure.

Abstract: The Smart Reamer® Tool, Apparatus or Method is used to underream an oil or natural gas well and deliver a desired wellbore diameter without the need to unnecessarily stop drilling or trip out of the hole.

Abstract: According to the present invention there is provided a method for installing a sensing cable along a pipeline, comprising the steps of, attaching one or more conduits to an outer-surface of a pipe which is to be installed in a bore hole to form a pipeline assembly; moving the pipeline assembly into the bore hole; moving an fiber optic sensing cable into one or more of the conduit after the pipeline assembly has been moved into the bore hole or before the pipeline assembly has been moved into the bore hole. There is further provided a corresponding pipeline assembly, and a attachment head which can facilitate attachment of a pulling line to a pipeline assembly.

Abstract: A reaming tool includes a body having a longitudinal axis and an upper end opposite a lower end and a blade located on said body, the blade including a reaming surface having one or more reaming inserts disposed on at least a portion thereof and a cutting surface having one or more cutters disposed on at least a portion thereof. One or more of said cutters are configured (a) so that an extended longitudinal axis of said cutter is positioned at an angle ? between 5 degrees and 85 degrees with respect to a plane perpendicular to the longitudinal axis of said body, or (b) on said cutting surface at a radial distance from said longitudinal axis less than said radial distances between said reaming inserts and said longitudinal axis.

Abstract: An isolator sub is disclosed. The isolator sub can include a first rod having a first coupling feature disposed at a first end. The isolator sub can also include a second rod having a second coupling feature disposed at a first end, where the first rod is electrically conductive. The isolator sub can further include an isolator made of an electrically non-conductive material and having a first complementary coupling feature and a second complementary coupling feature, where the first coupling feature couples to the first complementary coupling feature, and where the second coupling feature couples to the second complementary coupling feature. The isolator sub can also include an outer housing coupled to the first rod, the second rod, and the isolator, where the outer housing is electrically conductive and has at least one third coupling feature configured to electrically couple to an electrical cable.

Abstract: A downhole stabilizer (5), such as a drill motor stabilizer, comprises at least one reaming means and/or reinforcing means (10). The present invention also relates to an assembly (30), such as a downhole drilling assembly (31), comprising at least one such stabilizer (5) and/or a drill bit (40,41) comprising a gauge bit (42) at or near a drilling end (45) thereof, and a connection means (46) for connecting the drill bit (40,41) to a drill motor assembly (60), wherein the drill bit gauge (42) comprises a substantially cylindrical portion having a length less than or equal to approximately 1.0 times the nominal bit diameter. The present invention also relates to a novel locking mechanism (80), such as a lock and key mechanism, to allow locking of a shaft (70?), e.g. a motor drive shaft (71?), through or together with a stabilizer (5?).

Abstract: An apparatus includes a sub with recesses along an exterior wall to receive inserts, an antennae case including a coil surrounded by a sacrificial wear portion of a material through which signals between the coil and a formation of interest may pass. An eroded outer wall of the sacrificial wear portion is restorable by application of an uncured restorative material to the antennae case. A method includes securing an antennae case having a coil there within onto a sub, surrounding the coil with a metal sleeve shield, and radially receiving and securing a multi-piece sacrificial wear member intermediate the antennae case and a retainer ring having a threaded bore. The multi-piece sacrificial wear member is replaceable after use by unthreading the retainer ring to release the sacrificial wear member for radial removal from the sub.

Abstract: A bidirectional dual eccentric reamer which can form a larger wellbore than originally drilled and a wellbore larger than the drill bit diameter. The bidirectional dual eccentric reamer can have a shaft with a longitudinal axis supporting a plurality of reamer portions. The reamer portions have a plurality of helical blades of varying thicknesses. The plurality of helical blades can have a plurality of cutting nodes and cutting inserts. The plurality of helical blades can have a center of eccentric rotation which is offset from the longitudinal axis, thereby creating an eccentric rotation. This allows for the formation of a larger wellbore than originally drilled and a wellbore larger than the drill bit diameter.

Abstract: A reaming shell for mining is provided. The reaming shell has a shank, and a plurality of pads attached at circumferential intervals from each other to extend lengthwise on an outer periphery of the shank. The reaming shell is coupled to a core bit of a diamond drilling tool for mining. The reaming shell includes a water groove of a recessed shape formed respectively between each adjacent pair of the pads, and extending from a leading edge along a length of the shank.

Abstract: Underground drilling operation often requires connecting a drill tool (e.g., drill bit, backreamer, etc.) to a drill string. It is desirable to connect the drill tools to a drill string in a manner that facilitates quick and easy assembly and disassembly. Low torque coupling, commonly referred to as “torque-less” connection, can provide such functionality. The useful life and strength of such connections can be improved upon. The present disclosure provides a low torque coupling with improved strength and durability.

Abstract: A system for containing electronics positioned in a downhole tubular. The system includes a pressure housing, a rigid end piece, a compliant end piece, an inner tubular member, one or more annular standoffs, and a chassis. The pressure housing is supported within the downhole tubular. The rigid end piece and the compliant end piece are fixedly coupled within opposing ends of the pressure housing. The inner tubular member is disposed within the pressure housing and has opposing ends. One of the opposing ends is coupled to the rigid end piece, and the other of the opposing ends is free to move relative to the compliant end piece. The chassis is disposed within the inner tubular member and houses the electronics. Each standoff is disposed between the inner tubular member and the pressure housing and includes at least one radially extending portion compressed therebetween.

Abstract: Apparatus and methods for controlling drill string vibrations and applying a force to a drill bit include a body having a first piston at an uphole end in association with a drill string and a second piston at a downhole end in association with a drill bit. A first biasing member urges the first piston outward to provide a first force in an uphole direction to the drill string. A second biasing member urges the second piston outward to provide a second force in a downhole direction to the drill bit. When vibration from the drill string compresses the first biasing member, the first force resists the vibration and maintains the apparatus and drill bit in a consistent orientation. When an uphole force from the drill string or the drill bit compresses the second biasing member, the second force prevents movement of the drill bit in an uphole direction.

Abstract: A drillpipe for a drill stem to drill a hole. The drill stem includes a drill string and a bottom hole assembly. The drillpipe includes a first end having a first inertia, a second end having a second inertia, a first intermediate zone adjacent to the first end, a second intermediate zone adjacent to the second end, and a central substantially tubular zone with an external diameter smaller than the maximum external diameter of at least the first or the second end. A casing is fixed on the pipe over a portion of the external surface thereof, at least one physical parameter sensor is disposed in the casing, and at least one data transmission/storage mechanism is connected to the sensor output, the casing being disposed at a distance from the first and second ends, the casing being integral with the central zone at a distance from the first and second intermediate zones and having a smaller inertia than the first and second inertias.

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

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

Abstract: A driller retaining device able to be positioned with well horizontality and verticality includes a hollow outer sleeve having two end, one is a working end and the other being an assembly end; an inner wall of the assembly end being formed with a plurality of axial sliding tracks; an inner hollow cylinder arranged within the sleeve; two ends of the inner hollow cylinder being an machine end and an assembly end; an outer wall of the inner hollow cylinder having at least one sliding block which is arranged corresponding to the axial sliding groove. In in assembly, the inner hollow cylinder is combined to the driller; then the assembly end of the inner hollow cylinder is assembled to the assembly end of the outer sleeve; and at the same time, the sliding block of the inner hollow cylinder is assembled into the axial sliding groove of the outer sleeve.

Abstract: A joint connecting a pair of members rotatable about a common axis end to end includes a first member having a threaded end portion and a non-circular exterior surface rearwardly of the threaded end portion, a second member having a threaded socket wherein the threaded end portion of the second member can be engaged, and a non-circular exterior surface, a ground engagement sleeve having a non-circular profile on an inner surface thereof whereby the sleeve can be slidably mounted on the non-circular exterior profiles of the first and second members when such profiles are brought into alignment by rotation of one member relative to the other in a manner effective to pass torque from one member to the other by means of the non-circular profiles, a first pair of alignable holes in the sleeve and first member to receive a fastener to secure the sleeve to the first member and a hole in the second member penetrating the threaded socket and positioned to receive a fastener to secure the second member to a third membe