A wellbore lining system that puts liners into place immediately behind the drill head tool is used in drilling and for preparing natural gas hydrate (NGH) deposits for production of its natural gas. The system overcomes the requirement of setting casing from the wellhead, which controls well bore diameter with depth and allows for flexibility in well bore size at any depth. Wellbore liners stabilize the well walls by being very tightly fitting against bounding rocks and sediments, which overcomes the requirement for cementing, which commonly accompanies conventional well casing. In addition, liners can be emplaced with designed impermeability, permeability, and complex flow-through patterns so that production processes, such as sand flow, can be put in place as part of a liner section.

A downhole tool for transmitting rotation to a casing string includes a tool body having a bore extending from a first end to a second end. The downhole tool also includes a cam positioned within the tool body, the cam being axially translatable along an axis of the bore. The downhole tool further includes a recess, formed in an outer diameter of the cam. The downhole tool includes a locking mechanism, positioned at least partially within the tool body. The locking mechanism includes a tool key. The locking mechanism also includes a biasing member, the biasing member driving the tool key toward the retracted position.

Systems and methods for casing drilling riserless sections of a subsea bore may include casing drilling a section of a bore for a casing of the subsea bore to a predetermined depth. The method also may include, while casing drilling the section of the bore, obtaining information indicative of pore pressure and fracture pressure of a geological formation through which the section is casing drilled, and determining a pressure range based at least in part on the pore pressure, the fracture pressure, and a modification to mechanical properties of the geological formation due to the casing drilling of the section. The method further may include selecting, based at least in part on the pressure range and the predetermined depth, a pressure of the bore for casing drilling the section.

A method of locating bore-lining tubing, such as a liner (120), in a drilled bore (106) comprises selecting a buoyant material, such as air (138), having a density lower than the density of an ambient fluid, such as well fluid (180, 182). The buoyant material (138) and an inner tubing (140) are located within the bore-lining tubing (120) with the inner tubing (140) extending from a distal end of the bore-lining tubing to a proximal end of the bore-lining tubing. The inner tubing (140) is sealed to the distal end of the bore-lining tubing (120) and to a portion of the bore-lining tubing (120) spaced from the distal end to define an inner annulus (152) between the inner tubing (140) and the bore-lining tubing (120). A volume of the buoyant material (138) is retained within the inner annulus (152). An assembly (168) comprising the inner tubing (140) and the bore-lining tubing (120) and containing the volume of buoyant material (138) is run into a drilled bore (106). Fluid (126a) may be flowed through the inner tubing (140) and into an outer annulus (124) surrounding the bore-lining tubing (120).

A system for preventing annular pressure buildup comprising: a wellbore; two or more annuli located within the wellbore; a piston assembly located adjacent to a wellhead of the wellbore; and a pipe system that connects the two or more annuli in parallel to the piston assembly, wherein when the amount of pressure in the pipe system exceeds a predetermined amount, then a piston of the piston assembly moves whereby the movement reduces the amount of pressure in the two or more annuli.

A device is for reducing the load on a wellhead casing from a bending moment generated by a horizontal load component from a well element arranged over a wellhead. A supporting frame is connected to an upper portion of the wellhead casing and projects outwards from the center axis of the wellhead casing and is provided with an abutment which rests supportingly against a base at a radial distance from the wellhead casing. The supporting frame is arranged to absorb a portion of said bending moment.

A method of forming a wellbore includes providing a drilling assembly comprising one or more lengths of casing and an axially retracting assembly having a first tubular; a second tubular at least partially disposed in the first tubular and axially fixed thereto; and a support member disposed in the second tubular and movable from a first axial position to a second axial position relative to the second tubular, wherein, in the first axial position, the support member maintains the second tubular axially fixed to the first tubular, and in the second axial position, allows the second tubular to move relative to the first tubular; and an earth removal member disposed below the axially retracting assembly. The method also includes rotating the earth removal member to form the wellbore; moving the support member to the second axial position; and reducing a length of the axially retracting assembly.

Reducing the diameter of a well bore has many advantages. To achieve this a subsurface well bore is provided comprising one or more expandable sleeve components, preferably expandable liners, each expandable sleeve component being fully overlapped by one or more non expandable sleeve component, preferably conventional liners, such that the interior of the well bore is cased entirely by non expandable sleeve components. In addition the through holes for downhole lines can be provided within the well head rather than the tubing hanger. As the tubing hanger does not need to provide space for through holes and associated mounting couplings, its diameter can be reduced, thus reducing the internal diameter of the well bore by several inches.

System, method, and apparatus for harnessing geothermal power from superhot geothermal fluid (SHGF) and magma reservoirs. An exemplary apparatus can include a well screen coupled to an end of a casing string. The well screen, which is at least partially submerged within an underground reservoir, defines a volume in the underground reservoir that can be filled with superhot geothermal fluid. A slidable casing is aligned coaxially with the well screen and configured to be repositioned relative to the well screen. A draw pipe extending through the slidable casing is configured to convey SHGF from the underground reservoir towards the surface in response to the slidable casing being repositioned to obstruct more of a set of apertures in the well screen and an increase in pressure within a cavity of the slidable casing.

Casing installation assemblies for installing a casing within a borehole, as well as systems and methods related thereto are disclosed. In an embodiment, the casing installation assembly includes a tubular string, an isolation sub coupled to a downhole end of the tubular string, and a diverter sub coupled to and positioned downhole of the isolation sub. In addition, the casing installation assembly includes a landing string coupled to the diverter sub and configured to be coupled to the casing. The isolation sub includes a valve assembly that is configured to selectively prevent fluid communication between the tubular string and the diverter sub.