The present invention provides a spacer (11) and a spacer segment (13). One or more spacer segments (13) form the spacer (11). The one or more spacer segments (13) are adapted to be interconnected and fitted to/on a first surface. The spacer segment (13) comprises a first collar portion (17), a second collar portion (19), and at least one support assembly (15) extending between the first collar portion and the second collar portion. The at least one support assembly is movable from a normal position, wherein no or minimal force is exerted on the support assembly, to a compressed position, wherein the support assembly supports a load or a portion of a load.

A system includes a flexi-string having a first lateral end, a second lateral end, and an outer diameter. The outer diameter defines an outer circumferential surface, and the outer diameter is smaller than an inner diameter of a casing shoe. The system further includes an anchor disposed on the outer circumferential surface of the first lateral end, where the anchor interacts with the casing shoe, or a last joint of casing, to hold the first lateral end of the flexi-string within the casing shoe. The system also has centralizers located between the first lateral end and the second lateral end of the flexi-string. The centralizers are configured to center the flexi-string within the casing shoe and the washout section. Finally, the system includes a roller guide for lowering the flexi-string inside the casing shoe and to a depth below the washout section of the well.

A method for drilling a subterranean wellbore includes rotating a bottom hole assembly (BHA) in the wellbore to drill. The BHA includes a rotary steerable tool or a steerable drill bit having at least one external pad that extends radially outward into contact with a wall of the wellbore and thereby steers while drilling. A toolface demand is received and processed to compute open and close toolface angles for opening and closing a valve that actuates the steering pad. The rotation rate of the BHA is measured and processed to compute times for opening and closing the valve. The valve is opened and closed at the computed times and toolface angles at which the valve opens and closes are measured. The open and close toolface angles are compared with the measured toolface values to obtain a toolface error which is then processed to compute new open and close toolface angles.

A method for drilling a subterranean wellbore includes rotating a bottom hole assembly (BHA) in the wellbore to drill. The BHA includes a rotary steerable tool or a steerable drill bit having at least one external pad configured to extend radially outward into contact with a wall of the wellbore and thereby steer the drilling. A rotation rate of the BHA is measured and a drilling parameter waveform is received. The rotation rate and the waveform are processed to select discrete times for extending the at least one external pad while drilling.

Downhole cutting tool positioning assemblies and methods to cut a tubular are presented. The assembly includes a drive screw, a drive nut coupled to the drive screw and configured to shift from a first position to a second position as the drive screw rotates in a first drive screw direction, a pressure piston configured to shift from a first position to a second position in response to force applied to the pressure piston, a chamber having a pressure fluid that is pressurized by the pressure piston as the pressure piston shifts from the first position towards the second position, a sleeve configured to slide from a first position towards a second position in response to pressure from the pressure fluid, and a latch key having a profile configured to shift radially to engage a tubular groove as the sleeve shifts from the first position towards the second position.

A rotary steering tool includes a steering member configured to move between a retracted configuration and an extended configuration. The rotary steering tool also includes a pump configured to pump a fluid, a power source independent of the downhole motor, the power source configured to power the pump, and a piston in fluid communication with the pump. The piston is configured to apply a force to the steering member to move the steering member from the retracted configuration to the extended configuration when the pump pumps the fluid at an operating system pressure. The rotary steering tool includes a controller to operate the pump at a range of operating system pressures, and a variable pressure control valve. The variable pressure control valve adjusts the operating system pressure between the range of operating system pressures to adjust the force applied to the steering member.

Bottom hole assemblies with a combined roller-underreamer assembly can include: a body configured to be attached to a drill pipe; an uphole ring attached to the body; a downhole ring attached to the body between the uphole ring and the downhole end of the body; a sliding ring mounted around the body between the uphole ring and the downhole ring; a set tube slidably mounted around the body between the uphole ring and the sliding ring; a reamer assembly with at least one first articulated arm with extending between the uphole ring and the downhole end of the set tube; and a roller assembly with: at least one second articulated arm extending between the uphole end of the set tube and the sliding ring; and a rolling positioned at a joint of each second articulated arm.

A valve apparatus having a valve body configured with a flow passage. There is a main piston movably disposed within the flow passage, and configured to move to and from a first piston position to a second piston position. The valve apparatus also has a movable member movably disposed within the valve body, the movable member comprising: a no-go position for stopping movement of the main piston, and a go position to facilitate movement of the main piston.

Provided, in one aspect, is a downhole tool. The downhole tool, according to this aspect, may include a helically wound structure having first and second ends, as well as a first member coupled to the first end and a second member coupled to the second end. In accordance with this aspect, the first and second members are rotatable or linearly translatable with respect to each other to move the helically wound structure between a radially retracted state having at least one coils and a radially deployed state.

A system for an adjustably flexible downhole tool includes first and second connector ends each configured to connect to adjacent downhole tools and a shaft extending between the first and second connector ends. The shaft is configured to bend in response to passing through curved portions of a wellbore. The adjustably flexible downhole tool also includes an outer sleeve disposed around at least a portion of the shaft and extending from the first connector end in a direction toward the second connector end and at least one adjustable member configured to move axially, with respect to the shaft, from a first position to a second position to increase bending stiffness and/or torsional stiffness of the adjustably flexible downhole tool. The at least one adjustable member at least partially restrains bending of the shaft in the second position.