Abstract: An apparatus and method for removing cuttings in a deviated borehole using drilling fluids. The apparatus includes a pipe string and a bottom hole assembly having a down hole motor and bit for drilling the borehole. The pipe string has one end attached to the bottom hole assembly and does not rotate during drilling. The apparatus and methods raise at least a portion of the pipe string in the deviated borehole to remove cuttings from underneath the pipe string portion.

Abstract: An anchor system for high expansion applications is described. It features a gripping member that holds together a pair of links. The movement of the links is regulated to assure the gripping member moves into proper contact with the casing. Meshing gears or a pin and slot can do this, for example. The gripping member is shaped such that it can still transmit load through the links even if the pin connections fail. The gripping member is preferably contoured to the shape of the casing inner wall to enhance grip.

Abstract: A method and apparatus for propelling a tool having a body within a passage. The tool includes a gripper including at least a gripper portion which can assume a first position that engages an inner surface of the passage and limits relative movement of the gripper portion relative to the inner surface. The gripper portion can also assume a second position that permits substantially free relative movement between the gripper portion and the inner surface of the passage. The tool includes a propulsion assembly for selectively continuously moving the body of the tool with respect to the gripper portion while the gripper portion is in the first position. This allows the tool to move different types of equipment within the passage. For example, the tool advantageously may be used in drilling processes to provide continuous force to a drill bit. This enables the drilling of extended horizontal boreholes.

Abstract: A hydraulically powered tractor adapted for advancement through a borehole including an elongate body, aft and forward gripper assemblies, and a valve control assembly housed within the elongate body. The aft and forward gripper assemblies are adapted for selective engagement with the inner surface of the borehole. The valve control assembly includes a gripper control valve for directing pressurized fluid to the aft and forward gripper assemblies. The valve control assembly also includes a propulsion control valve for directing fluid to an aft or forward power chamber for advancing the body relative to the actuated gripper assembly. Aft and forward mechanically actuated valves may be provided for controlling the position of the gripper control valve by detecting and signaling when the body has completed an advancement stroke relative to an actuated gripper assembly.

Abstract: Subsea controlled milling apparatus and methods. In a described embodiment, a method of controlling displacement of a cutting device conveyed on a tubular string in a subterranean well includes the steps of: interconnecting an apparatus in the tubular string, the apparatus including an axial advancement device and an anchoring device; actuating the anchoring device to anchor the apparatus in the well; applying a pressure differential to the advancement device, thereby displacing the cutting device relative to the apparatus; and operating the cutting device to cut a structure in the well.

Abstract: A fluid delivery system for degrading valuable items in the event on an attack is provided. A piston 30 is disposed within a cylinder 2. On demand gas under pressure can be admitted into the cylinder 2 so as to urge the piston to move towards an outlet 8, thereby expelling fluid 4 irrespective of the orientation of the delivery system.

Abstract: A hydraulically powered tractor includes an elongated body, two gripper assemblies, at least one pair of aft and forward propulsion cylinders and pistons, and a valve system. The valve system comprises an inlet control valve, a two-position propulsion control valve, a two-position gripper control valve, two cycle valves, and two pressure reduction valves. The inlet control valve spool includes a hydraulically controlled deactivation cam that locks the valve in a closed position, rendering the tractor non-operational. The propulsion control valve is piloted on both ends by fluid pressure in the gripper assemblies. The propulsion control valve controls the distribution of operating fluid to and from the propulsion cylinders, such that one cylinder performs a power stroke while the other cylinder performs a reset stroke. Each end of the gripper control valve is piloted by a source of high-pressure fluid selectively admitted by one of the cycle valves.

Abstract: A method and apparatus for propelling a tool having a body within a passage. The tool includes a gripper including at least a gripper portion which can assume a first position that engages an inner surface of the passage and limits relative movement of the gripper portion relative to the inner surface. The gripper portion can also assume a second position that permits substantially free relative movement between the gripper portion and the inner surface of the passage. The tool includes a propulsion assembly for selectively continuously moving the body of the tool with respect to the gripper portion while the gripper portion is in the first position. This allows the tool to move different types of equipment within the passage. For example, the tool advantageously may be used in drilling processes to provide continuous force to a drill bit. This enables the drilling of extended horizontal boreholes.

Abstract: A subsurface apparatus in the form a tractor is adapted for travel through a bore containing a moving fluid stream. The tractor comprises a body, a drive arrangement for moving the body in a desired direction, a member mounted on the body and adapted to be driven by the moving fluid, and a conversion arrangement for converting movement of the member to drive for the drive arrangement. The drive arrangement may include a contactless magnetic coupling and a harmonic drive.

Abstract: A gripper assembly for anchoring a tractor within a downhole passage and for assisting movement of the tractor within the passage. The gripper assembly includes an elongated mandrel and flexible toes that can be radially displaced to grip onto the surface of the passage. The toes are displaced by the interaction of a driver slidable on the mandrel and a driver interaction element on the toes. In one embodiment, the toes are displaced by the interaction of rollers and ramps that are longitudinally movable with respect to one another. In another embodiment, the toes are displaced by the interaction of toggles that rotate with respect to the toes.

Abstract: A device for anchoring a drill string in a borehole formed in an earth formation is provided. The device comprises an anchoring member connected to the drill string and being movable between a retracted position in which the anchoring member is retracted from the borehole wall and an extended position in which the anchoring member is extended against the borehole wall so as to anchor the drill string to the borehole wall, and an activating member operable to move the anchoring member from the extended position to the retracted position by the action of pressure of drilling fluid present in the borehole.

Abstract: A method and apparatus for propelling a tool having a body within a passage. The tool includes a gripper including at least a gripper portion which can assume a first position that engages an inner surface of the passage and limits relative movement of the gripper portion relative to the inner surface. The gripper portion can also assume a second position that permits substantially free relative movement between the gripper portion and the inner surface of the passage. The tool includes a propulsion assembly for selectively continuously moving the body of the tool with respect to the gripper portion while the gripper portion is in the first position. This allows the tool to move different types of equipment within the passage. For example, the tool advantageously may be used in drilling processes to provide continuous force to a drill bit. This enables the drilling of extended horizontal boreholes.

Abstract: Grouting equipment and methods suitable for use in underground water wells, which accomplish their goals by better centering the grouting equipment within a bore hole, even in curved bore holes, in an manner that prevents leakage of the grout into the well. Improved grouting is achieved by using corrugated, bendable incasings and expandable tubes which create a seal between the incasing and the well wall for the grout, and which prevent both contaminated surface water and grout from contaminating the groundwater. The disclosed techniques are implementable in such a manner that grouting does not necessarily need to precede the location of a groundwater nappe.

Abstract: A method and apparatus for advancing a rotating motorized downhole tool for operations in oil/gas wells. The apparatus is adapted for drilling and milling away of casing sections in the wells, as preparation for plugging the same. The apparatus includes a rotating tool and a driving motor indirectly suspended on coiled tubing. The apparatus also includes a carriage connected to the motor adapted to absorb torques that occur during use. The carriage is connected to the coiled tubing via a swivel coupling such that a tensile force on the coiled tubing provides an advancing force for the tool and motor.

Abstract: A downhole sampling tool and related method are provided. The tool is provided with a main flowline for communicating fluid from the formation through the tool. A main valve is positioned in the main flowline and defines a first portion and a second portion of the main flowline. At least one sample chamber with a slidable piston therein defining a sample cavity and a buffer cavity is also provided. The sample cavity is in selective fluid communication with the first portion of the main flowline via a first flowline and with the second portion of the main flowline via a second flowline. Fluid communication is selectively established between the sample cavity and the first and/or second portions of the main flowline for selectively flushing fluid through the sample cavity and/or collecting samples of the fluid therein. Fluid may also be discharged from the buffer cavity via a third flowline.

Abstract: A gripper assembly for anchoring a tractor within a downhole passage and for assisting movement of the tractor within the passage. The gripper assembly includes an elongated mandrel and flexible toes that can be radially displaced to grip onto the surface of the passage. The toes are displaced by the interaction of a driver slidable on the mandrel and a driver interaction element on the toes. In one embodiment, the toes are displaced by the interaction of rollers and ramps that are longitudinally movable with respect to one another. In another embodiment, the toes are displaced by the interaction of toggles that rotate with respect to the toes.

Abstract: A gripper assembly for anchoring a tractor within a downhole passage and for assisting movement of the tractor within the passage. The gripper assembly includes an elongated mandrel and flexible toes that can be radially displaced to grip onto the surface of the passage. The toes are displaced by the interaction of a driver slidable on the mandrel and a driver interaction element on the toes. In one embodiment, the toes are displaced by the interaction of rollers and ramps that are longitudinally movable with respect to one another. In another embodiment, the toes are displaced by the interaction of toggles that rotate with respect to the toes.

Abstract: A six-bar linkage mechanism for conforming to the configuration of a tractored surface having a central link defined by a tool body and a saddle link spaced from the central link and movable for conforming with the tractored surface. A pair of front links each having pivotal connection with respective ends of the saddle link and having linearly movable pivotal connection with the central link to permit angular and spacing changes of the saddle link relative to the central link. A pair of centralizer links are located between the front links and have pivotal connections with the saddle link and pivotal connections with the central link. One of the pivotal connections is linearly movable on the central link. For tractor tools, when the tractored surface is a wellbore or well pipe, a plurality of six-bar linkages radiate from a tool body for surface conforming traction with the tractored surface.

Abstract: A method and apparatus for propelling a tool having a body within a passage. The tool includes a gripper including at least a gripper portion which can assume a first position that engages an inner surface of the passage and limits relative movement of the gripper portion relative to the inner surface. The gripper portion can also assume a second position that permits substantially free relative movement between the gripper portion and the inner surface of the passage. The tool includes a propulsion assembly for selectively continuously moving the body of the tool with respect to the gripper portion while the gripper portion is in the first position. This allows the tool to move different types of equipment within the passage. For example, the tool advantageously may be used in drilling processes to provide continuous force to a drill bit. This enables the drilling of extended horizontal boreholes.

Abstract: A downhole drilling tractor for moving within a borehole comprises a tractor body, two packerfeet, two aft propulsion cylinders, and two forward propulsion cylinders. The body comprises aft and forward shafts and a central control assembly. The packerfeet and propulsion cylinders are slidably engaged with the tractor body. Drilling fluid can be delivered to the packerfeet to cause the packerfeet to grip onto the borehole wall. Drilling fluid can be delivered to the propulsion cylinders to selectively provide downhole or uphole hydraulic thrust to the tractor body. The tractor receives drilling fluid from a drill string extending to the surface. A system of spool valves in the control assembly controls the distribution of drilling fluid to the packerfeet and cylinders. The valve positions are controlled by motors. A programmable electronic logic component on the tractor receives control signals from the surface and feedback signals from various sensors on the tool.

Abstract: Apparatus for boring a hole from an inside of a tube outwardly perpendicular to a longitudinal axis of the tube comprises a drill shoe having a longitudinal axis and being positionable in the tube, the shoe having an inlet, an outlet perpendicular to the shoe longitudinal axis and a passageway connecting the inlet and outlet, a torsional load transmitting element having no torsional flexibility in relation to its bending flexibility, having a longitudinal axis and being disposed in the passageway, the torsional load transmitting element being movable relative to itself with no resistance about first and second perpendicular axes both of which are perpendicular to the longitudinal axis of the torsional load transmitting element, a hole saw connected to one end of the torsional load transmitting element and a motor rotatably connected to the other end of the torsional load transmitting element.

Abstract: A sample module for use in a downhole tool includes a sample chamber for receiving and storing pressurized fluid. A piston is slidably disposed in the chamber to define a sample cavity and a buffer cavity, and the cavities have variable volumes determined by movement of the piston. A first flowline is provided for communicating fluid obtained from a subsurface formation through the sample module. A second flowline connects the first flowline to the sample cavity, and a third flowline connects the sample cavity to one of the first flowline and an outlet port. A first valve is disposed in the second flowline for controlling the flow of fluid from the first flowline to the sample cavity, and a second valve is disposed in the third flowline for controlling the flow of fluid out of the sample cavity, whereby any fluid preloaded in the sample cavity may be flushed therefrom using the formation fluid in the first flowline and the first and second valves.

Abstract: A gripper assembly for anchoring a tractor within a downhole passage and for assisting movement of the tractor within the passage. The gripper assembly includes an elongated mandrel and flexible toes that can be radially displaced to grip onto the surface of the passage. The toes are displaced by the interaction of a driver slidable on the mandrel and a driver interaction element on the toes. In one embodiment, the toes are displaced by the interaction of rollers and ramps that are longitudinally movable with respect to one another. In another embodiment, the toes are displaced by the interaction of toggles that rotate with respect to the toes.

Abstract: A hydraulically powered tractor includes an elongated body, two gripper assemblies, at least one pair of aft and forward propulsion cylinders and pistons, and a valve system. The valve system comprises an inlet control valve, a two-position propulsion control valve, a two-position gripper control valve, two cycle valves, and two pressure reduction valves. The inlet control valve spool includes a hydraulically controlled deactivation cam that locks the valve in a closed position, rendering the tractor non-operational. The propulsion control valve is piloted on both ends by fluid pressure in the gripper assemblies. The propulsion control valve controls the distribution of operating fluid to and from the propulsion cylinders, such that one cylinder performs a power stroke while the other cylinder performs a reset stroke. Each end of the gripper control valve is piloted by a source of high-pressure fluid selectively admitted by one of the cycle valves.

Abstract: A traction apparatus (1A) includes at least one traction member (51) which engages a surface (10A) against which traction is to be provided. The traction member can move relatively freely in one direction over the surface but has high resistance to movement in the other direction. The apparatus can be made to move by having a number of traction members (5156) which move or oscillate relative to each other. There are preferably a large number of traction members which are in the forms of bristles in a brushlike part of the apparatus. The apparatus is suitable for use in downhole tools. The bristles are bent in a first direction by being constrained in a hole facilitating movement in the opposite direction but preventing movement in the first direction.

Abstract: A gripper assembly for anchoring a tractor within a downhole passage and for assisting movement of the tractor within the passage. The gripper assembly includes an elongated mandrel and flexible toes that can be radially displaced to grip onto the surface of the passage. The toes are displaced by the interaction of a driver slidable on the mandrel and a driver interaction element on the toes. In one embodiment, the toes are displaced by the interaction of rollers and ramps that are longitudinally movable with respect to one another. In another embodiment, the toes are displaced by the interaction of toggles that rotate with respect to the toes.

Abstract: A tractor for moving within a borehole comprises an elongated tractor body and two propulsion assemblies that are longitudinally movably engaged with the body. The tractor body has annular pistons configured to receive hydraulic thrust to propel the body longitudinally. Each propulsion assembly includes a gripper and one or more propulsion cylinders. The gripper has an actuated position in which the gripper limits relative movement between the gripper and the inner surface of the borehole, and a retracted position in which the gripper permits substantially free relative movement between the gripper and the inner surface of the borehole. Each propulsion cylinder contains one of the pistons. The tractor includes a control assembly having a plurality of valves and hydraulic circuitry which control the sequencing of fluid distribution to the propulsion cylinders, and of the actuation and retraction of the grippers. A throttle valve controls the fluid flowrate to the pistons.

Abstract: The present invention provides a drilling assembly for drilling deviated wellbores. The drilling assembly includes a drill bit at the lower end of the drilling assembly. A drilling motor provides the rotary power to the drill bit. A bearing assembly of the drilling motor provides lateral and axial support to the drill shaft connected to the drill bit. A steering device is integrated into drilling motor assembly. The steering device contains a plurality of force application members disposed at an outer surface of the drilling motor assembly Each force application member is adapted to move between a normal position and a radially extended position to exert force on the wellbore interior when in extended position. A power unit in the housing provides pressurized fluid to the force application members. A control device for independently operating each of the force application members is disposed in the drilling motor assembly.

Abstract: The device contemplated provides a method for positioning the drill bit in a drilling operation to achieve small changes in hole angle or azimuth as drilling proceeds. Two different positions are available to the operator. The first is a straight ahead position where the tool essentially becomes a packed hole stabilizer assembly. The second position tilts the bit across a rotating fulcrum to give a calculated offset at the bit-formation interface. The direction that the bit offset is applied in relation to current hole direction is controlled by positioning the orienting pistons prior to each drilling cycle, through the use of current measurement-while-drilling (MWD) technology. Components of the tool comprise a MWD housing, upper steering and drive mandrel, non-rotating position housing, lower drive mandrel splined with the upper mandrel, rotating fulcrum stabilizer and drill bit.

Abstract: Apparatus for boring a hole from an inside of a tube outwardly perpendicular to a longitudinal axis of the tube comprises a drill shoe having a longitudinal axis and being positionable in the tube, the shoe having an inlet, an outlet perpendicular to the shoe longitudinal axis and a passageway connecting the inlet and outlet, a torsional load transmitting element having no torsional flexibility in relation to its bending flexibility, having a longitudinal axis and being disposed in the passageway, the torsional load transmitting element being movable relative to itself with no resistance about first and second perpendicular axes both of which are perpendicular to the longitudinal axis of the torsional load transmitting element, a hole saw connected to one end of the torsional load transmitting element and a motor rotatably connected to the other end of the torsional load transmitting element.

Abstract: A downhole drilling tractor for moving within a borehole comprises a tractor body, two packerfeet, two aft propulsion cylinders, and two forward propulsion cylinders. The body comprises aft and forward shafts and a central control assembly. The packerfeet and propulsion cylinders are slidably engaged with the tractor body. Drilling fluid can be delivered to the packerfeet to cause the packerfeet to grip onto the borehole wall. Drilling fluid can be delivered to the propulsion cylinders to selectively provide downhole or uphole hydraulic thrust to the tractor body. The tractor receives drilling fluid from a drill string extending to the surface. A system of spool valves in the control assembly controls the distribution of drilling fluid to the packerfeet and cylinders. The valve positions are controlled by motors. A programmable electronic logic component on the tractor receives control signals from the surface and feedback signals from various sensors on the tool.

Abstract: A tractor for moving within a borehole comprises an elongated tractor body and two propulsion assemblies that are longitudinally movably engaged with the body. The tractor body has annular pistons configured to receive hydraulic thrust to propel the body longitudinally. Each propulsion assembly includes a gripper and one or more propulsion cylinders. The gripper has an actuated position in which the gripper limits relative movement between the gripper and the inner surface of the borehole, and a retracted position in which the gripper permits substantially free relative movement between the gripper and the inner surface of the borehole. Each propulsion cylinder contains one of the pistons. The tractor includes a control assembly having a plurality of valves and hydraulic circuitry which control the sequencing of fluid distribution to the propulsion cylinders, and of the actuation and retraction of the grippers. A throttle valve controls the fluid flowrate to the pistons.

Abstract: A method and apparatus for propelling a tool having a body within a passage. The tool includes a gripper including at least a gripper portion which can assume a first position that engages an inner surface of the passage and limits relative movement of the gripper portion relative to the inner surface. The gripper portion can also assume a second position that permits substantially free relative movement between the gripper portion and the inner surface of the passage. The tool includes a propulsion assembly for selectively continuously moving the body of the tool with respect to the gripper portion while the gripper portion is in the first position. This allows the tool to move different types of equipment within the passage. For example, the tool advantageously may be used in drilling processes to provide continuous force to a drill bit. This enables the drilling of extended horizontal boreholes.

Abstract: A tractor for moving within a borehole comprises an elongated tractor body and two propulsion assemblies that are longitudinally movably engaged with the body. The tractor body has annular pistons configured to receive hydraulic thrust to propel the body longitudinally. Each propulsion assembly includes a gripper and one or more propulsion cylinders. The gripper has an actuated position in which the gripper limits relative movement between the gripper and the inner surface of the borehole, and a retracted position in which the gripper permits substantially free relative movement between the gripper and the inner surface of the borehole. Each propulsion cylinder contains one of the pistons. The tractor includes a control assembly having a plurality of valves and hydraulic circuitry which control the sequencing of fluid distribution to the propulsion cylinders, and of the actuation and retraction of the grippers. A throttle valve controls the fluid flowrate to the pistons.

Abstract: A tractor system has been invented which, in certain embodiments, includes a body connected to the item, first setting means on the body for selectively and releasably anchoring the system in a bore, first movement means having a top and a bottom, the first movement means on the body for moving the body and the item, the first movement means having a first power stroke, and the tractor system for moving the item through the bore at a speed of at least 10 feet per minute.

Abstract: A tractor system for moving an item through a wellbore has been invented with a central mandrel interconnected with the item, first setting means about the central mandrel for selectively and releasably anchoring the system in a wellbore, the central mandrel having a top, and a bottom, and a first power thread therein, the first setting means having a first follower pin for engaging the first power thread to power the first setting means to set the first setting means against an inner wall of the bore. In one aspect, the tractor system is for moving the item through the bore at a speed of at least 10 feet per minute.

Abstract: A method and apparatus for propelling a tool having a body within a passage. The tool includes a gripper including at least a gripper portion which can assume a first position that engages an inner surface of the passage and limits relative movement of the gripper portion relative to the inner surface. The gripper portion can also assume a second position that permits substantially free relative movement between the gripper portion and the inner surface of the passage. The tool includes a propulsion assembly for selectively continuously moving the body of the tool with respect to the gripper portion while the gripper portion is in the first position. This allows the tool to move different types of equipment within the passage. For example, the tool advantageously may be used in drilling processes to provide continuous force to a drill bit. This enables the drilling of extended horizontal boreholes.

Abstract: Excavating equipment comprising a rigid support structure with articulately mounted surface clamps, an excavating device downstream of the surface clamps in a direction of excavation and an urging device for urging the excavation means in a direction of excavation during excavating. The equipment further comprises a power device coupled to the excavating device for operating same and for operating the urging device. The power device is also coupled to the surface clamps for laterally displacing the surface clamps against rigid supporting surfaces so as to generate a counter-reaction to forces generated by operation of the excavating device. Additionally, a displacing device is coupled to the support structure for displacing the equipment into and out of an excavation.

Abstract: A new wellbore tractor system has been invented which, in one aspect has at least two slip units for alternately and releasably anchoring the system within a wellbore or within a tubular member and at least two movement units for moving an item in a wellbore, such as, but not limited to cable, tubing, casing, a tubular string or coiled tubing. In one aspect power strokes of the movement units overlap in time so that the system provides continuous motion. In another aspect a wellbore tractor system has been invented for moving an item through a wellbore, the wellbore extending from earth surface to an underground location, the system comprising a body connected to the item, first setting means on the body for selectively and releasably anchoring the system in a wellbore, first movement apparatus on the body for moving the body and the item, the first movement means having a first power stroke, and the wellbore tractor system for moving the item through the wellbore at a speed of at least 100 feet per minute.

Abstract: A tether puller for advancing a tether through a channel may include a bellows assembly having a leading end fixedly attached to the tether at a first position and a trailing end fixedly attached to the tether at a second position so that the leading and trailing ends of the bellows assembly are located a substantially fixed distance apart. The bellows assembly includes a plurality of independently inflatable elements each of which may be separately inflated to an extended position and deflated to a retracted position. Each of the independently inflatable elements expands radially and axially upon inflation. An inflation system connected to the independently inflatable elements inflates and deflates selected ones of the independently inflatable elements to cause the bellows assembly to apply a tractive force to the tether and advance it in the channel.

Abstract: A go-devil (1) is inserted into a pipe end of a pipe (5) laid in place in trenchless manner by ramming or pressing and of which the earth core (7) shall be removed by a method of the invention, said go-devil being displaced longitudinally through said pipe and forcing the said earth core out at the other pipe end. The advance of the go-devil (1) takes place step by step by means of a length-variable actuator (10) bracing itself against the inside wall (4) of the pipe (5), said actuator after each forward stroke being returned into its initial position and its bracing being made to follow in the direction of advance by the amount of the step taken.

Abstract: A sidewall coring tool for wireline use in an earth bore hole is provided which includes an elongated tool body adapted for suspension within the bore hole by the wireline cable at a selected depth, low speed high torque rotary coring bit apparatus mounted within the elongated tool body and cooperating therewith for advancing and retracting a rotary coring bit transversely therefrom for drilling and recovering a large core sample from the sidewall of the bore hole, and decentralizing arm apparatus mounted in the tool body on the side opposite the side of the body from which the rotary coring bit is advanced, the decentralizing arm apparatus spaced above and below the location of the rotary coring apparatus for deploying decentralizing arms from the tool body into contact with the bore hole walls and forcing the side of the tool body from which the rotary coring bit will be advanced into contact with the bore hole wall and for maintaining the tool body in rigid contact during the coring operation.

Abstract: A rock drilling machine of the self-feeding, integrated type which is designed to operate in situ in a drill hole. The rock drilling machine comprises a drive unit (1), an anchoring unit (2), and a feeding unit (3) which is active between the anchoring unit (2) and the drive unit (1). The drive unit (1) comprises a hydraulic power assembly (5, 8) at the rear end of the unit, a drill bit (21) which is rotatable at the front end of the unit, a guide (10) with a longitudinal cavity (23), which guide extends between the hydraulic power assembly and the drill head and connects these non-rotatably to each other, a rotatable drive shaft (22) which extends from the hydraulic power assembly, through the said cavity in the guide, for rotation of the drill bit, and first securing devices (17) in order to be able to anchor the drive unit releasably in the drill hole.

Abstract: A string of sondes is designed to be lowered down a borehole by means of a cable in order to detect the arrival of seismic waves therein, the sondes including retractable anchor means that are hydraulically actuateable and that are connected by a hydraulic circuit to a common source of hydraulic pressure. The string includes means for putting said hydraulic circuit to ambient pressure, said means being connected to said cable and being adapted to act on said hydraulic circuit in order to cause said anchor means to be retracted when a traction force exceeding a selected value is exerted on said cable.

Abstract: An orientation mandrel rotatable in an orientation body for providing rotational orientation and actuated by a hydraulic piston controlling the position of a helix. A thruster may be connected to the orientation mandrel and is adapted to hydraulically engage the well bore by plurality of elongate gripping bars. An annular thruster piston is hydraulically and longitudinally movable in the thruster body for extending the thruster mandrel outwardly from the thruster body. However, the orientating tool and thruster may be used separately.

Abstract: A power generation unit associated with a downhole drilling motor capable of producing sufficient rotational speeds to produce power for operating downhole devices associated with the drilling operation. The power generation unit takes advantage of the high speed precessional rotation of the rotor within the stator to drive the generator. The assembly includes a multi-lobed rotor displaceable within a stator using drilling fluid pumped therethrough. A crankshaft, mounted at one end concentric with the rotor and at its high speed take-off end concentric with the stator, transfers the rotor center precession to the shaft of the generator. In a preferred embodiment, the generator will include a socket for simply connecting downhole devices requiring electrical power.

Abstract: A device for guiding a drilling tool into a well and for exerting a hydraulic force on the drilling tool includes a tubular body and an outer sleeve rotating about the body and longitudinally displaceable with respect to the body. Also, the device includes radially displaceable pistons, in an extension position, that come into anchoring engagement with the wall of the well and immobilize the external sleeve, as well as a jack to displace the body and the drilling tool integral therewith with respect to the external sleeve and to exert a pushing force onto the tool. Hydraulic circuits and appropriate control assembly are also provided for controlling the execution of a series of successive cycles of anchoring of the external sleeve in the well and of displacement of the drilling tool with respect to the external sleeve.

Abstract: An apparatus for driving an upwardly directed shaft in rock, which includes a platform that can be regulated in height. The platform carries a drilling unit having engageable elements enabling fixation of the drilling unit relative the wall of the shaft. The drilling unit and platform can be separated a given distance such as to form an air gap for preventing the transfer of vibrations from the drilling unit to the platform when a drilling machine pertaining to the drilling unit is in operation. The apparatus has bracket elements and a transverse member for limiting the separation distance between the drilling unit and platform. The platform carries a work station for a drilling machine operator.

Abstract: For the drilling of bore holes there is provided an assembly of drilling machine elements which are positioned on top of each other and which include a gripping body comprising of two or more shells between which are positioned expanding-contracting cylinders for causing the shells to be pressed against the wall of a hole being drilled, a hollow drive shaft and a drilling tool being suspended below the gripping body. In addition to the above mentioned gripping body which acts outwardly of the center of the assembly, there are provided gripping plates which act radially inwardly of the hollow drive shaft to grip the stem of the drilling tool, which extends within the hollow drive shaft.

Abstract: A device for submarine foundation drilling includes: a drilling unit including a head and body interconnected by at least one cylinder, the body being equipped with at least one cutter, the drilling unit being equipped with at least one excavating pump, and hydraulic motors to operate the cutter and the pump; a rigid tubular assembly (2) containing at least one discharge pipe, and pipes for feeding hydraulic fluid to the cylinder and the motors; connecting means (12) between the head of the drilling unit and the lower part of the tubular construction; support means (13) able to be placed at the ocean bottom in front of the head of the drilling unit, means for clamping the tubular assembly; means for suspending the device from a ship, means (5) being provided to furnish hydraulic power, and connecting pipes being provided between the means of furnishing fluid and the upper end of the tubular assembly.