Abstract: A vibration assembly of a drilling tool for drilling a wellbore penetrating a subterranean formation is disclosed. The downhole drilling tool includes a drill string, a bottomhole assembly and a drill bit. The vibration assembly includes a housing (334a) operatively connectable to the bottomhole assembly, expanders (122) positionable in the housing and radially extendable and retractable thereabout, and a radial vibrator (comprising mandrel (446), enlarger spring (48), cam portion (458) and vibration spring (570) operatively connectable to the expanders to vibrationally move the expanders against the wall of the wellbore whereby movement of the downhole tool is altered during drilling.

Abstract: A drilling assembly assembly includes a hammer motor, a shaft, a driver, and a hammer (218). The shaft is operatively connectable to the hammer motor and rotated thereby. The driver is operatively connectable to the shaft, and includes a cam (such as guide channel 232) rotatable with the shaft and a fixed guide (such as guide pins 230) having a guide surface thereon. The cam is engageable with the guide surface and axially movable thereabout during rotation thereof. The hammer is operatively connectable to the driver and axially movable therewith, axially movable within the housing (215) independently from axial movement of the housing, and engageable with the bit to impart an impact thereto whereby the bit is hammered.

Abstract: A downhole tool (10) comprising rotatable inner and outer sleeves (62, 63). The sleeves (62, 63) comprise coupling portions for transmitting a torque between the sleeves (62, 63). The tool is reconfigurable between a first configuration whereby the coupling portions are axially misaligned to prevent transmission of torque between the inner and outer sleeves (62, 63), and a second configuration whereby the coupling portions are axially aligned to permit a transmission of torque between the sleeves (62, 63). At least one of the coupling portions is configured to prevent the transmission of torque above a predetermined torque threshold.

Abstract: A vibration assembly of a drilling tool for drilling a wellbore penetrating a subterranean formation is disclosed. The downhole drilling tool includes a drill string, a bottomhole assembly and a drill bit. The vibration assembly includes a housing (334a) operatively connectable to the bottomhole assembly, expanders (122) positionable in the housing and radially extendable and retractable thereabout, and a radial vibrator (comprising mandrel (446), enlarger spring (48), cam portion (458) and vibration spring (570) operatively connectable to the expanders to vibrationally move the expanders against the wall of the wellbore whereby movement of the downhole tool is altered during drilling.

Abstract: A method of running a bore-lining tubing string into a bore includes running a tubing string, typically a liner string, into a bore while agitating the string. The agitation may also take place while the tubing is being cemented in the bore. Pressure pulses may be applied to fluid in the bore, which fluid may be cement slurry.

Abstract: A powered reamer comprising a stationary assembly having a flow bore therethrough. A rotating assembly is disposed about the stationary assembly and one or more cutting structures are coupled to an outer surface of the rotating assembly. A flow restriction is disposed within the flow bore so as to divert a portion of fluid flowing through the flow bore through an outlet from the flow bore into an annulus between the stationary assembly and the rotating assembly. A power section is formed in the annulus between the stationary assembly and the rotating assembly. The power section operates to eccentrically rotate the rotating assembly about the stationary assembly in response to fluid flowing through the annulus between the stationary assembly and the rotating assembly.

Abstract: A downhole tool including a fluid-actuated piston and a motor-driven valve. The fluid-actuated piston is operatively associated with a reciprocating mass. The motor-driven valve is configured to supply actuating fluid sequentially to drive the piston downwards and upwards. A method of reciprocating a mass in a downhole tool. The method including cycling a motor-driven valve between a first configuration and a second configuration. In the first configuration actuating fluid pressure drives a piston associated with the mass downwards. In the second configuration actuating fluid pressure drives the piston upwards.

Abstract: A pulse generator comprises a stator coupled to a housing and a rotor that is rotatably disposed within the housing. An annulus is formed between the rotor and the stator. An inner bore is formed through the rotor. One or more outer flow ports provide fluid communication between the annulus and the inner bore. A retrievable valve assembly is rotationally coupled to the rotor and at least partially disposed within the inner bore. The retrievable valve assembly includes a rotary valve member having one or more primary flow ports. A fluid flow path is periodically formed by the one or more outer flow ports, the annulus, and the one or more primary flow ports as the rotor rotates.

Abstract: A powered reamer comprising a stationary assembly having a flow bore therethrough. A rotating assembly is disposed about the stationary assembly and one or more cutting structures are coupled to an outer surface of the rotating assembly. A flow restriction is disposed within the flow bore so as to divert a portion of fluid flowing through the flow bore through an outlet from the flow bore into an annulus between the stationary assembly and the rotating assembly. A power section is formed in the annulus between the stationary assembly and the rotating assembly. The power section operates to eccentrically rotate the rotating assembly about the stationary assembly in response to fluid flowing through the annulus between the stationary assembly and the rotating assembly.

Abstract: A drilling assembly assembly includes a hammer motor, a shaft, a driver, and a hammer (218). The shaft is operatively connectable to the hammer motor and rotated thereby. The driver is operatively connectable to the shaft, and includes a cam (such as guide channel 232) rotatable with the shaft and a fixed guide (such as guide pins 230) having a guide surface thereon. The cam is engageable with the guide surface and axially movable thereabout during rotation thereof. The hammer is operatively connectable to the driver and axially movable therewith, axially movable within the housing (215) independently from axial movement of the housing, and engageable with the bit to impart an impact thereto whereby the bit is hammered.

Abstract: A downhole tool (10) comprising rotatable inner and outer sleeves (62, 63). The sleeves (62, 63) comprise coupling portions for transmitting a torque between the sleeves (62, 63). The tool is reconfigurable between a first configuration whereby the coupling portions are axially misaligned to prevent transmission of torque between the inner and outer sleeves (62, 63), and a second configuration whereby the coupling portions are axially aligned to permit a transmission of torque between the sleeves (62, 63). At least one of the coupling portions is configured to prevent the transmission of torque above a predetermined torque threshold.

Abstract: A tubular retrieval method involves applying a cyclically varying fluid pressure to the interior of a section of cut bore-lining tubular. The tubular may be casing which it is desired to remove from a bore. A pulling force may also be applied to the tubular.

Abstract: A method of translating a member through a bore involving moving fluid through a tubular member such as a drill string, and generating impulses on the member by varying the passage of fluid through the member using a valve which opens at a first rate and closes at a different second rate to urge the member to advance in a selected direction. The valve may close quickly and open slowly, or may close slowly and open quickly.

Abstract: A pulse generator comprises a stator coupled to a housing and a rotor that is rotatably disposed within the housing. An annulus is formed between the rotor and the stator. An inner bore is formed through the rotor. One or more outer flow ports provide fluid communication between the annulus and the inner bore. A retrievable valve assembly is rotationally coupled to the rotor and at least partially disposed within the inner bore. The retrievable valve assembly includes a rotary valve member having one or more primary flow ports. A fluid flow path is periodically formed by the one or more outer flow ports, the annulus, and the one or more primary flow ports as the rotor rotates.

Abstract: A method of operating a downhole tool in a no-flow configuration in which a piston and a flow-restriction cooperate to occlude a tool throughbore. The tool is reconfigured to an intermediate configuration by flowing fluid through the tool at an intermediate flow-rate lower than an operating flow-rate and axially translating the piston to an intermediate position in which the piston and flow-restriction cooperate to define an intermediate flow area. Axial translation of the piston between a no-flow position and the intermediate position includes an occlusional stage of a first axial extent during which the piston and the flow-restriction occlude the tool throughbore, and a transitional stage of a second axial extent during which the piston and the flow-restriction cooperate to provide a step-change in flow area. The tool is reconfigured to an operating configuration by flowing fluid through the tool at the operating flow-rate and axially translating the piston.

Abstract: A drilling assembly, drilling system and method is provided. The drilling system includes a drilling rig with a drill string deployable therefrom and drivable thereby. The drill string has a bottom hole assembly with a drill bit at a lower end thereof advanceable into a subterranean formation to form a wellbore. The drilling assembly includes at least one mandrel operatively connectable to the drill string, at least one sleeve positionable about the mandrel (the sleeve having an offset stabilizer on an outer surface thereof selectively positionable in contact with a wall of the wellbore), and an orienter with a receptacle on an interior of the sleeve and a socket on an exterior of the mandrel. The socket is interlockingly engageable with the receptacle whereby the sleeve is orientable about the drill string. The one mandrel and the sleeve have a mass offset from the drill string whereby rotation of the drill string is affected during drilling.

Abstract: A tubular retrieval method comprises applying a cyclically varying fluid pressure to the interior of a section of cut bore-lining tubular (20). The tubular may be casing which it is desired to remove from a bore. A pulling force may also be applied to the tubular.

Abstract: Drilling apparatus comprises: a body; a pilot hole-drilling assembly (14) mounted to the body for drilling a pilot hole of a first diameter; and a hole-opening assembly (16) mounted to the body for opening the pilot hole to a larger second diameter. The apparatus is configured such that the pilot hole-drilling assembly (14) will drill at a faster rate than the hole-opening assembly (16) for a given unit loading. As the pilot hole-drilling assembly (14) has the capability to drill at a faster rate than the hole-opening assembly (16), the pilot hole-drilling assembly will tend to experience relatively low weight-on-bit (WOB). The pilot hole-drilling assembly (14) will thus tend to maintain a vertical orientation. The hole-opening assembly (16) will follow the path of the pilot hole, while opening the hole to the required diameter.

Abstract: A method of translating a member through a bore comprises moving fluid through a tubular member such as a drill string (2A), and generating impulses on the member by varying the passage of fluid through the member using a valve (60) which opens at a first rate and closes at a different second rate to urge the member to advance in a selected direction. The valve may close quickly and open slowly, or may close slowly and open quickly.

Abstract: A downhole tool including a fluid-actuated piston and a motor-driven valve. The fluid-actuated piston is operatively associated with a reciprocating mass. The motor-driven valve is configured to supply actuating fluid sequentially to drive the piston downwards and upwards. A method of reciprocating a mass in a downhole tool. The method including cycling a motor-driven valve between a first configuration and a second configuration. In the first configuration actuating fluid pressure drives a piston associated with the mass downwards. In the second configuration actuating fluid pressure drives the piston upwards.