Abstract: In certain embodiments, a downhole swivel sub includes a first swivel part configured to connect to a first section of a workstring, and a second swivel part configured to connect to a second section of the workstring. The second swivel part is rotatable relative to the first swivel part. The downhole swivel sub also includes a locking sleeve rotationally coupled with the first swivel part and movable axially between a locking position wherein the first swivel part and the second swivel part are rotationally coupled and an unlocking position wherein the first swivel part is rotatable relative to the second swivel part. The locking sleeve includes at least two first rows of teeth disposed at a same radial position and separated axially on the locking sleeve. The at least two first rows of teeth are configured to engage and disengage with at least two second rows of teeth located on the second swivel part.

Abstract: The invention relates to a connecting assembly to be plugged into a mating receptacle in a wellbore, comprising a first sleeve including a second sleeve and having a top connecting end and a bottom connecting end, characterized in that: —the first sleeve comprises the bottom end and has a top end opposite to said bottom connecting end, said bottom connecting end being provided with an end cap for preventing entrance of materials and capable of being opened; —said second sleeve comprises said top connecting end located outside of the first sleeve and has a bottom end opposed to said top connecting end; —said connecting assembly comprises a locking mechanism adapted to lock said second sleeve in a position relative to said first sleeve such that the bottom end of the second sleeve is inside said first sleeve, and —the dimensions of the first sleeve and second sleeve are adapted such that when said locking mechanism is unlocked, said second sleeve is allowed to move relative to said first sleeve to impinge and o

Abstract: A drill string comprises a mechanical drill bit and a ram accelerator with a launch tube proximate to the mechanical drill bit. A projectile accelerated by the ram accelerator exits the mechanical drill bit through an orifice and impacts a geologic formation. The impact weakens a portion of the formation, enabling the drill bit to penetrate the weakened portion more easily. An endcap may be used to prevent outside material from entering the ram accelerator. The projectile may pass through or otherwise displace the endcap during operation. The launch tube may be positioned at an angle relative to the drill bit such that projectiles impact and weaken the formation on a particular side. Contact between the drill bit and the formation may direct the drill bit toward the weakened side, enabling the ram accelerator to be used to steer the drill bit.

Abstract: A steering assembly includes a housing having a longitudinal axis, a mandrel having a front connecting extremity and a rear connecting extremity, the mandrel passing through the housing and arranged in a first position coaxially to the longitudinal axis of the housing, a deflector device configured to exert a side force on the mandrel to offset the front connecting extremity of the mandrel from the longitudinal axis, and a tool face assembly configured to rotate the front connecting extremity of the mandrel in a desired direction.

Abstract: The invention relates to a swivel sub for a string to be lowered into a wellbore and a method of operation in a wellbore, wherein such swivel sub is used and comprises: —a first end provided with connection means for connecting a bottom section of a string; —a second end provided with connection means for connecting an upper section of the string; —a first member, including the first end and a sleeve portion opposed to the first end; —a second member including the second end and comprising a section opposed to the second end and partially located within the sleeve portion; the first member and the second member being arranged to rotate relative to each other.

Abstract: A drill string comprises a mechanical drill bit and a ram accelerator with a launch tube proximate to the mechanical drill bit. A projectile accelerated by the ram accelerator exits the mechanical drill bit through an orifice and impacts a geologic formation. The impact weakens a portion of the formation, enabling the drill bit to penetrate the weakened portion more easily. An endcap may be used to prevent outside material from entering the ram accelerator. The projectile may pass through or otherwise displace the endcap during operation. The launch tube may be positioned at an angle relative to the drill bit such that projectiles impact and weaken the formation on a particular side. Contact between the drill bit and the formation may direct the drill bit toward the weakened side, enabling the ram accelerator to be used to steer the drill bit.

Abstract: The invention relates to a connecting assembly to be plugged into a mating receptacle in a wellbore, comprising a first sleeve including a second sleeve and having a top connecting end and a bottom connecting end, characterized in that: the first sleeve comprises the bottom end and has a top end opposite to said bottom connecting end, said bottom connecting end being provided with an end cap for preventing entrance of materials and capable of being opened; said second sleeve comprises said top connecting end located outside of the first sleeve and has a bottom end opposed to said top connecting end; said connecting assembly comprises a locking mechanism adapted to lock said second sleeve in a position relative to said first sleeve such that the bottom end of the second sleeve is inside said first sleeve, and the dimensions of the first sleeve and second sleeve are adapted such that when said locking mechanism is unlocked, said second sleeve is allowed to move relative to said first sleeve to impinge and open

Abstract: The present invention relates to a tool for selectively connecting or disconnecting components of a downhole workstring comprising a drive shaft (3) and a housing couplable to said drive shaft, and housing comprising first and second housing parts (21, 22) releasably connected to one another, transmission means such as a reduction gear mechanism (52-54) coupled to the drive shaft, the transmission means being arranged to selectively connect or disconnect the housing parts by rotating the drive shaft.

Abstract: In certain embodiments, a downhole swivel sub includes a first swivel part configured to connect to a first section of a workstring, and a second swivel part configured to connect to a second section of the workstring. The second swivel part is rotatable relative to the first swivel part. The downhole swivel sub also includes a locking sleeve rotationally coupled with the first swivel part and movable axially between a locking position wherein the first swivel part and the second swivel part are rotationally coupled and an unlocking position wherein the first swivel part is rotatable relative to the second swivel part. The locking sleeve includes at least two first rows of teeth disposed at a same radial position and separated axially on the locking sleeve. The at least two first rows of teeth are configured to engage and disengage with at least two second rows of teeth located on the second swivel part.

Abstract: The invention relates to a swivel sub for a string to be lowered into a wellbore and a method of operation in a wellbore, wherein such swivel sub is used and comprises: a first end provided with connection means for connecting a bottom section of a string; a second end provided with connection means for connecting an upper section of the string; a first member, including the first end and a sleeve portion opposed to the first end; a second member including the second end and comprising a section op posed to the second end and partially located within the sleeve portion; the first member and the second member being arranged to rotate relative to each other.

Abstract: A steering assembly includes a housing having a longitudinal axis, a mandrel having a front connecting extremity and a rear connecting extremity, the mandrel passing through the housing and arranged in a first position coaxially to the longitudinal axis of the housing, a deflector device configured to exert a side force on the mandrel to offset the front connecting extremity of the mandrel from the longitudinal axis, and a tool face assembly configured to rotate the front connecting extremity of the mandrel in a desired direction.

Abstract: The assembly comprise a bent sub (1411), and optionally a swivel (1480). The bend angle a of the bent sub in relation to the central axis of the assembly can be adjusted by rotating lower bend member (1431) relative to upper bend member (1430), which is non-rotatably attached to downhole motor (1460), using harmonic drive (1413) arranged between lower and upper bend members. In order to adjust the rotational orientation of the bent sub (1411), a swivel (1480) is provided having upper and lower swivel members (1432, 1433). Upper swivel member can be rotated relative to lower member, which is non-rotatably attached to the downhole motor, using a second harmonic drive (1423) arranged between lower and upper swivel members.

Abstract: The present invention relates to a tool for selectively connecting or disconnecting components of a downhole workstring comprising a drive shaft (3) and a housing couplable to said drive shaft, said housing comprising first and second housing parts (21, 22) releasably connected to one another, transmission means such as a reduction gear mechanism (52-54) coupled to the drive shaft, the transmission means being arranged to selectively connect or disconnect the housing parts by rotating the drive shaft.

Abstract: A steering assembly includes a housing having a longitudinal axis, a mandrel having a front connecting extremity and a rear connecting extremity, the mandrel passing through the housing and arranged in a first position coaxially to the longitudinal axis of the housing, a deflector device configured to exert a side force on the mandrel to offset the front connecting extremity of the mandrel from the longitudinal axis, and a tool face assembly configured to rotate the front connecting extremity of the mandrel in a desired direction.

Abstract: A downhole tool includes a mandrel, an inner sleeve, and an outer housing. The inner sleeve being rotatable relative to the outer housing and the mandrel being rotatable relative to the inner sleeve and the outer housings. The outer surface of the inner sleeve includes more than one selected position organized in at least one set. At least two of the selected positions include magnets. The downhole tool also includes at least one magnetic sensor to sense at least one of the amplitude and polarity of the magnetic field for the selected positions and to transmit a signal indicative of the sensed magnetic field. The downhole tool also includes an electronics system to process the sensor signal to determine a magnet reference position of the inner sleeve relative to the outer housing.

Abstract: A rotary vector gear for controlling longitudinal axis offset about a central longitudinal axis is disclosed. The device uses single rotary motion through a rotary vector gear to produce hypotrochoidic offset similar to a flower petal and is capable or ready return to zero offset. The device may be used in downhole rotary steerable oil and gas drilling tools and in computer controlled milling machines for providing controlled offset.

Abstract: A rotary vector gear for controlling longitudinal axis offset about a central longitudinal axis is disclosed. The device uses single rotary motion through a rotary vector gear to produce hypotrochoidic offset similar to a flower petal and is capable or ready return to zero offset. The device may be used in downhole rotary steerable oil and gas drilling tools and in computer controlled milling machines for providing controlled offset.

Abstract: An inductive coupling system including a mandrel and an inner sleeve and outer housing that surround and rotate relative to the mandrel. The system also includes a mandrel electronics system and a housing electronics system that communicate electronically using a mandrel inductive coupler and a housing inductive coupler. The mandrel electronics system may also communicate with equipment on the surface. Alternatively, the system may include a mandrel and first and second mandrel electronics systems in different mandrel sections. The first and second mandrel electronics systems communicate electronically using a mandrel inductive coupler. Also alternatively, the system may include a mandrel and an inner sleeve and outer housing that surround and rotate relative to the mandrel. The system also includes a mandrel electronics system and a housing electronics system that communicate electronically using a housing inductive coupler.

Abstract: An apparatus for selectively controlling the direction of a well bore comprising a mandrel rotatable about a rotation axis; a direction controller means comprising at least two parts configured to apply a force to said mandrel with a component perpendicular to the said rotation axis; a housing having an eccentric longitudinal bore forming a weighted side and being configured to freely rotate under gravity; and a driver for selectively varying the angle of the force relative to the weighted side of the housing about said rotation axis, the driver being configured to move the two parts independently of one another.

Abstract: An apparatus for selectively controlling the direction of a well bore comprising a mandrel rotatable about a rotation axis; a direction controller means comprising at least two parts configured to apply a force to said mandrel with a component perpendicular to the said rotation axis; a housing having an eccentric longitudinal bore forming a weighted side and being configured to freely rotate under gravity; and a driver for selectively varying the angle of the force relative to the weighted side of the housing about said rotation axis, the driver being configured to move the two parts independently of one another.