Abstract: A method to establish a well using a nested drill/completion string. The nested drill/completion string includes an inner pipe nested in an outer pipe, a flow crossover disposed at an end of the nested drill string and a drill bit disposed to one side of the flow crossover. Drilling fluid is pumped into the well through a first annular space between the inner pipe and the outer pipe, and drill cuttings created by the drill bit are returned to surface through in inner pipe. For the completion of the well, either (i) fluid in the annular space is displaced with a lower conductivity fluid or (ii) the annular space; is evacuated. Fluid to be heated is pumped through a second annular space between the well and the exterior of the nested drill string and geothermally heated fluid is moved from the subsurface to the surface through the inner pipe.

Abstract: A well completion pipe has a plurality of pipe joints, each comprising an outer pipe, an intermediate layer disposed inside the outer pipe and an inner pipe disposed inside the layer. The inner pipe extends longitudinally beyond a respective longitudinal end of the outer pipe or the outer pipe extends longitudinally beyond a respective longitudinal end of the inner pipe. The inner pipe and the outer pipe comprise respective threaded connections at each longitudinal end. The respective threaded connections form a metal to metal seal when engaged to corresponding mating threads. A pressure isolated passageway extends through the intermediate layer. In some embodiments, the inner pipe comprises well casing. In some embodiments, the outer pipe comprises a well completion tubular.

Abstract: A casing drilling system includes combination conduit of a casing and a pipe inside the casing. A first adapter has a flow diverter to redirect at least flow of drilling fluid returning from a bottom of a wellbore to either an interior of the pipe or an annular space between the casing and the pipe. A second adapter has a flow diverter to redirect flow of drilling fluid into the conduit through the other one of the interior of the pipe and the annular space. The second adapter has a fluid connection between either the interior of the pipe or the annular space and a rotationally fixed fluid outlet. The system includes a casing chuck having means to support the casing and a slidable conduit operable to expose an uppermost end of the casing and a connection between the second adapter and an uppermost end of the pipe.

Abstract: The present invention regards a sealing arrangement for a valve, comprising a valve element (3) provided with a sealing element (4), arranged to be abutting a valve seat (2) in a closed state of the valve. The valve element (3) comprises at least two parts, a first and second part (31,32), each comprising an abutting surface (310,320), which abutting surfaces (310,320) are arranged facing each other and to abut against corresponding sealing element surfaces (41,42) of the sealing element (4), and whereof at least one part (31) of the valve element (3) is being arranged to be moveable relative another part (32) of the valve element (3) and the at least one part (31) of the valve element (3) comprises a pressure surface (311) exposed to a surrounding fluid in a closed state of the valve giving pressure on the sealing element (4) responsive to the pressure in the surrounding fluid.

Abstract: A down hole well tool for installing a casing or liner in a well bore includes a tool unit and an expansion module for expansion of the casing or liner. The expansion module has at least two sets of rolling means arranged along an axial direction of the expansion module, and each set of rolling means is provided at an outer circumference of the expansion module. The diameter of the rolling means decreases at least between the two sets along the expansion module, providing the expansion module with a decreasing diameter in an axial down hole direction of the well bore.

Abstract: A down hole well tool (3) for installing a casing/liner (1) in a well bore (2), wherein the down hole well tool comprises a tool unit comprising at least one first fluid conduit (6) and a return fluid conduit (5) in use forming an annulus between the tool unit and the casing/liner. The tool unit further comprises at least one piston (7a, 7b) in the annulus dividing the annulus into annulus spaces (8a, 8b, 8c). At least two expansion modules (9a, 9b) for the expansion of the casing are positioned displaced in the axial direction of the casing. The expansion modules are arranged to be moved relative to each other in the axial direction of the casing.

Abstract: The present invention relates to a system for transferring signals through a drill pipe system during drilling of a subsurface well. The drill pipe system comprises a first pipe (1) provided concentric inside a second pipe (2) by means of hanging devices (3, 3a). The first pipe (1) is electrically insulated from the second pipe (2). A first signal transceiver is electrically connected to the top of the drill pipe system. A second signal transceiver is electrically connected along or in the bottom of the drill pipe system. The first and second signal transceivers are electrically connected to the first and second pipes (1, 2) for transferring the signals through the drill pipe system.

Abstract: A sealing system between a relatively rotating element and a stationary element has at least three sealing elements arranged between the rotating element and the stationary element and arranged in series between a process fluid and an environment, and a barrier fluid arrangement to provide a barrier fluid to spaces formed between the sealing elements. The barrier fluid arrangement has at least two compensator devices where under use the pressure in the process fluid is acting on one side of a piston in the compensator device and the pressure in the barrier fluid is acting on the opposite side of the piston. There is a difference between cross sectional areas of the two sides of the piston and the difference varies between the at least two compensator devices.

Abstract: The present invention regards a valve device for use with a down hole tool comprising at least a first fluid line and a return fluid line, the valve device comprises a first inlet and a first outlet forming a first flow path between them, and a second inlet and a second outlet forming a second flow path between them, at least one closure element for closing and or opening at least one of the flow paths. According to the invention there is at least one closure element together with the respective flow paths forms a first and second check valves, which in a first state prevents a fluid from flowing from the first outlet to the first inlet and a fluid from flowing from the second inlet to the second outlet. The invention also regards a method for operating a down hole valve device.

Abstract: The invention concerns a unit for a down hole well tool comprising a tool unit comprising at least one first fluid conduit and a return fluid conduit in use forming a well annulus space between the tool unit and the well bore. The tool unit is arranged with at least one piston provided for dividing the well annulus space into at least two well annulus spaces. The communication of fluid between the adjacent well annulus spaces at each side of the piston is controlled by the relative movement between the first fluid conduit and a control element.

Abstract: The present invention relates to a method for cleaning and possibly sealing a subsurface well. According to the method a multichannel tool string comprising an adapter on a first end of the tool string, a guide device at the second end of the tool string are run into the well, whereupon the guide device is activated in order to permit the well to be flushed by the supply of fluid through at least one of the channels in connection with the tool string and fluids and particles from the well are transported back to the surface through at least one other of the channels in connection with the tool string. The invention also relates to a device for cleaning and possibly sealing a subsurface well.

Abstract: A method and device for a running tool for drilling or cleaning and setting a lining and a completion string in an underground borehole. The running tool comprising a drilling tool, an expandable casing, an expansion tool, a packer arranged to seal against the wall of the casing, and at least one conduit extending up to the surface. The drilling tool is releasably connected to the lower portion of the expanding casing, and the expansion tool and the packer are releasably connected to the upper portion of the expanding casing. The running tool is arranged to communicate with the surface through at least one pipe conduit.

Abstract: A method and a device for establishing an underground borehole (10) and setting a casing (6) in the borehole (10), wherein the running tool (1) including a drilling tool (14), an expandable casing (6), an expansion tool (32) and a packer (30) which is arranged to seal against the wall of the borehole (10), is placed at the bottom of the borehole (10), whereupon the borehole (10) is drilled to the necessary length in order then to set the expandable casing (6), and in subsequent operations the casing is reinforced and a completion string is run, having built-in cables for downhole control and monitoring.