Abstract: An assembly for use to cement an uncased wellbore and create a sidetrack of a wellbore with a single trip into the wellbore. The assembly includes a mill selectively connected to a whipstock. A snorkel tube is positioned within a bore of the mill and within a bore of the whipstock. The assembly is connected to drill string and positioned within an openhole portion of the wellbore. After the assembly has been anchored, cement may be pumped down the drill string and through the snorkel tube. The mill may be removed from the whipstock by shearing a shearable device connecting the mill to the whipstock. The mill is used engage a diverting surface on the whipstock and create a sidetrack. The mill may also mill a portion of the snorkel tube or the snorkel tube may be removed from wellbore up the drill string prior to milling the sidetrack.

Abstract: A backup ring design for a packer sealing element features a folding shape where opposed legs are pushed together for extension in a radial direction toward the surrounding tubular to span the extrusion gap. The design can use a V-shape where the vertex is toward the mandrel and the legs are oriented toward the surrounding tubular. The legs in that instance can be thicker than the vertex thickness to aid in folding while providing enhanced strength at the surrounding tubular where shear forces apply as a result of seal compression against the surrounding tubular. The design features a single or multiple vertices that are similarly aligned or alternatingly oppositely aligned to create a zigzag shape in cross-section. Material selection can vary with the expected service conditions.

Abstract: An apparatus for suspending a liner within a bore comprising a central tubular member and first and second sets of radially expandable arms. Each set of arms are expandable by corresponding longitudinally movable cones spaced apart along the tubular member. The apparatus further includes a seal located between the first and second sets of radially expandable arms and a selectably longitudinally compressible sleeve located between the first and second sets of radially expandable arms.

Abstract: A downhole tool and associated methods. The downhole tool includes a body with a throughbore; at least one extendable cutting member; and an actuation member. The actuation member is operatively associated with the extendable cutting member and movable relative to the body to extend the cutting member laterally from the body along an extension axis. The extension axis is offset from a radius of the body.

Abstract: A downhole injection tool has an injection unit with a first expandable cup adapted to provide a first seal against the inside wall, and a second expandable cup adapted to provide a second seal against the inside wall. The two cups, in an expanded state, together define an isolated zone of the annular space. At least one pipe element extends in a longitudinal direction between the two cups, the pipe element providing a fluid passage between an inlet arranged in one end of the pipe element and an outlet arranged in the pipe element in between the cups, the second expandable cup being slidably connected with the pipe element and displaced in the longitudinal direction away from the first expandable cup under the influence of the injection fluid injected into the isolated zone, whereby a distance d between the two cups is increased.

Abstract: A lock capable of self-locking onto a tubular and onto another centralizer. The lock collar being of the type used in production strings of tubulars in the oilfield. The lock collar relates to mechanisms such as stop rings for centralizers commonly used in downhole applications to prevent axial and rotational movement of centralizers mounted on the tubing or casing outer surface.

Abstract: A fluid sensor for a downhole tool positionable in a wellbore penetrating a subterranean formation. The downhole tool has a housing with a flowline therethrough receiving a downhole fluid therein. The fluid sensor includes an insulative base positionable in the downhole tool, a conductive shield positionable on the insulative base, and a plurality of electrodes each having a non-conductive coating thereon. Each of the electrodes includes a sensing element and a pin. The sensing element is positionable in the insulative base and exposed to the downhole fluid passing through the flowline. The pin operatively connects the sensing element to a downhole unit whereby parameters of the downhole fluid are measured.

Abstract: A rotary drill and a double-layer drilling rod mechanism are disclosed. A connecting rod (2) is provided in the rotary connecting sleeve (9), and the rotary connecting sleeve (9) is connected with the double-layer drilling rod mechanism (11). An impact drilling string (25) located by a guide bearing bush (26) is arranged in the outer rotary drilling pipe (28) of the double-layer drilling rod mechanism (11); a latch (24) for connecting the connecting rod (2) is arranged at the top of the inner impact drilling string (25); and an impact head (12) connected with the impact drilling string (25) is arranged in the drilling bit connecting sleeve (29). The drilling bit (13) below the impact head (12) is connected with the drilling bit connecting sleeve (29) by a front connector (30).

Abstract: Apparatus, systems, and methods for continuously circulating drilling fluid through a tubular string are described. The methods include connecting a sub having a central bore and a side bore to the tubular string, connecting a top drive to the tubular string, connecting a manifold to the sub and top drive, wherein the manifold comprises a plurality of electrically controlled valves, and controlling the flow of drilling fluid through the sub and top drive by selectively opening and closing the electrically controlled valves.

Abstract: A mechanism for selectively activating a plurality of downhole pathways. The method includes a casing segment which includes a plurality of casing ribs, a valve which includes a sleeve coupled for movement between an open and normally closed position, a rocker member mounted to the sleeve, a dart for pumping in hole including a dart profile matched to the rocker member profile such that the dart profile couples to the rocker member profile when in close proximity and, in turn, the sleeve moves using hydraulic force from the closed position to the open position.

Abstract: A system for placement of a liner in a lateral wellbore, access to which is provided through a window having a V-shaped downhole end. The system includes a running tool including an upper end through which the running tool is manipulated from surface, a lower end, a key positioned between the upper end and the lower end, the key protruding from the running tool for locating the V-shaped downhole end of the window and a liner-engaging portion on the downhole end for releasably securing the wellbore liner to the running tool, the liner-engaging portion configured to secure the liner adjacent the key with the key protruding above the liner and the liner extending from the lower end. The invention also provides methods for placing a wellbore liner in a lateral wellbore extending from a main wellbore.

Abstract: A downhole retrieval tool for engaging and retrieving an object from a wellbore includes a mandrel and a grapple having a contracted position and an expanded position. In the expanded position, the grapple engages the object for retrieval. The grapple is operably associated with an expansion member disposed on the mandrel to facilitate movement of the grapple between the contracted and expanded positions. The expansion member is releasably connected to the mandrel. In the event that the downhole tool and object, once secured to each other, are unable to be retrieved from the wellbore, the expansion member can be released from the mandrel which, in turn, causes the grapple to release from the object so that the downhole tool can be removed from the wellbore. A stored energy member facilitates movement of the grapple from the contracted position to the expanded position.

Abstract: Drill string assemblies, bottom hole assemblies (BHAs), and powertrains for a BHA in a drill string are presented herein. A BHA for use in a drill string to drill boreholes in an earth formation is disclosed. The BHA includes a housing, a drill bit rotatably coupled to the housing, and a fluidly driven motor assembly, such as a positive displacement motor (PDM). The PDM assembly includes a drive shaft to output rotational drive forces generated by the PDM. Also included is a differential gear set with a first gear member coupled to the drive shaft, a second gear member intermeshing the first gear member with the housing, and a third gear member couple to the drill bit. The differential gear set transmits the rotational drive forces from the drive shaft to the drill bit and rotates the drill bit at a speed greater than the speed of the PDM assembly.

Abstract: A lock collar for locking a centralizer in place on a tubular of the type used in production strings in the oilfield. The lock collar relates to mechanisms such as stop rings or lock collars commonly used in downhole applications to prevent axial and/or rotational movement of centralizers mounted on the tubing or casing outer surface.

Abstract: A technique facilitates selectively disengaging a running string from a lateral tube assembly. The running string comprises a running sub which is engageable with the lateral tube assembly. The running string further comprises a window finder which is positioned to extend into a main bore casing window when the running string is deployed downhole with the lateral tube assembly. Additionally, the running string comprises an extension sub which is coupled to the window finder. The extension sub is selectively extensible to disengage the window finder from the main bore casing prior to release of the running sub from the lateral tube assembly via a release force applied through the running string.

Abstract: A centralizer capable of self-locking onto a tubular. The centralizer being of the type used in production strings of tubulars in the oilfield. The centralizer relates to mechanisms such as stop rings for centralizers commonly used in downhole applications to prevent axial and rotational movement of centralizers mounted on the tubing or casing outer surface.

Abstract: A setting assembly for a packer seal features peripherally mounted rod pistons that abut the seal to be set by advancing the seal relative to a tapered surface. When parts of the seal engage an inner tubular wall before other parts of the seal the continuation of application of hydraulic pressure to the pistons moves parts of the seal that have yet to make contact with the tubular wall further relative to the ramp so that plastic deformation of the seal assembly can occur to allow portions thereof to move radially further outwardly to seal in the region where the radius of the tubular is enlarged. When hydraulic pressure is applied to the pistons in an opposite direction a lock mechanism is defeated and the c-ring or scroll reverts to a smaller shape optionally aided by a garter spring so that the packer can be selectively retrieved.

Abstract: A method for determining along a length of a wellbore situated in an underground hydrocarbon-containing formation, regions within the formation to inject a fluid at a pressure above formation dilation pressure, to stimulate production of oil into the wellbore. An initial information-gathering procedure is conducted prior to formation dilation/fracturing, wherein fluid is supplied under a pressure less than formation dilation or fracture pressure, to discrete intervals along the wellbore, and sensors measure and data is recorded regarding the ease of penetration of such fluid into the various regions of the formation. Regions of the formation exhibiting poor ease of fluid penetration or regions of higher oil saturation, are thereafter selected for subsequent stimulation or dilation, at pressures above formation dilation pressures. Where initial fluid pressures and/or formation dilation pressures are provided in cyclic pulses, a downhole tool is disclosed for such purpose.

Abstract: Systems, devices and methods for evaluating a downhole fluid from a borehole intersecting an earth formation. The method may include filtering magnetic particles in the downhole fluid by activating a switchable magnetic filter when the downhole fluid enters a sample chamber in the borehole. The filter may include a wire mesh comprising strands of conductor oriented in a first direction; and strands of soft magnetic material oriented in a second direction. The method may also include cleaning the switchable magnetic filter by deactivating the switchable magnetic filter. Cleaning the switchable magnetic filter may include removing filtered particles using a fluid. The method may further include estimating a parameter of interest of the downhole fluid in the sample chamber.

Abstract: A wellhead hanger assembly is provided. In one embodiment, a system includes a wellhead hanger, such as a casing hanger. This system also includes a spacer ring positioned along a neck of the wellhead hanger between a threaded portion of the neck and a shoulder of the wellhead hanger. In at least some instances, the spacer ring may cooperate with a running tool threaded onto the wellhead hanger to reduce the break-out torque needed for disconnecting the running tool from the wellhead hanger. Additional systems, devices, and methods are also disclosed.