A tie-back string and a method of coupling the tie-back string to a casing is disclosed. The tie-back string is disposed within the casing. The tie-back string includes an anchor and an actuator section. The actuator section including a sleeve that forms a first chamber and a setting piston that forms a second chamber. A pressure differential is created between the first chamber and the second chamber to move the setting piston to engage the anchor of the tie-back string.

The present invention relates to a wireline expansion tool for setting of a completion tubular component such as a straddle, a liner, a patch or a liner hanger, the wireline expansion tool having an axial extension and comprising an electric motor connectable with and powered through a wireline, an axial force generator driven directly or indirectly by the electric motor for providing a movement along the axial extension, a radial expansion tool section connected with the axial force generator, and a completion tubular component, arranged at least partly around at least part of the radial expansion tool section for expanding at least part of the completion tubular component, wherein the radial expansion tool section comprises a first element movable along the axial extension by the axial force generator and a support structure connected with the first element, the support structure supporting the completion tubular component during expansion, and the first element being connected with the support structure for moving the support structure at least partly radially outwards for simultaneous expanding the completion tubular component. The invention also relates to a downhole tool string comprising the wireline expansion tool and a driving unit, such as a downhole tractor, for propelling the wireline expansion tool forward in the well.

A hydraulic thruster system for providing an axial force. In one embodiment, the system comprises a pump, a motor for driving the pump, and a hydraulic thruster comprising: a cylinder comprising a plurality of cylinder pistons; a shaft comprising a plurality of shaft pistons; a plurality of first pressure chambers; and a plurality of second pressure chambers, wherein the plurality of shaft pistons are positioned inside the cylinder, between the cylinder pistons to form the plurality of first and a second pressure chambers, wherein the shaft further comprises a first fluid passage connected to the pump and to the first pressure chambers, and a second fluid passage connected to the pump and to the second pressure chambers, and wherein the pump may pump fluid into the first pressure chambers and suction fluid from the second pressure chambers providing an axial force between the shaft and the cylinder.

A disposable setting tool includes a housing having a first end, a second end, and an intermediate portion having an outer surface and an inner surface defining a passage. A piston assembly is arranged in the passage. The piston assembly including a first piston portion and a second piston portion that extends axially outwardly of the second end of the housing. The first piston portion includes a first end portion, a second end portion, and an intermediate section having an outer surface portion and an inner surface portion that extends between the first end portion and the second end portion. The inner surface portion defines a pressure passage. An atmospheric chamber is defined between the inner surface of the housing and the outer surface portion of the piston assembly.

An actuating tool actuable by degradation of at least a portion of a seal assembly to set an auxiliary tool downhole in an oil and gas wellbore. A system and method for actuating the auxiliary tool downhole in the oil and gas wellbore using the actuating tool by degrading at least a portion of the seal assembly of the actuating tool.

A setting tool for setting a downhole tool comprises a housing attached at its downhole end to a setting mandrel. A piston is slidably movable axially inside the housing and defines an upper and lower pressure chambers within the housing. A power charge is disposed in the piston. A crosslink sleeve supported on the setting mandrel is coupled to a crosslink key that extends into a slot in the wall of the setting mandrel, such that movement of the crosslink key along the slot also moves the crosslink sleeve axially relative to the mandrel. To actuate the setting tool, the power charge is ignited to increase pressure in the upper pressure chamber, thereby exerting an axial force on the piston to directly push the crosslink key, along with the crosslink sleeve, to shift downhole relative to the housing. The shifting of the crosslink sleeve sets the downhole tool.

A technique facilitates setting of a liner hanger in a casing or within other tubular structures via a setting tool. The liner hanger may be constructed with an expandable hanger body between fixed ends. The expandable hanger body is formed from a material, e.g. metal, sufficiently ductile to undergo plastic deformation as it is expanded into engagement with a surrounding casing or other tubing. The expandable hanger body is expanded via fluid delivered under high pressure by the setting tool. The setting tool has a pressure booster to achieve the desired high pressure. The pressure booster may be in the form of a multi-diameter piston constructed to establish the desired high pressure during a single stroke.

A system and method set a liner hanger in a borehole by actuating a hydraulic setting mechanism on the hanger to engage slips in the borehole. A setting tool runs the hanger into position. A reserve volume of the tool holds a clean fluid separate from the borehole. A piston of the tool has a tool volume for the fluid. During run in, pressure in the tool volume is balanced to hydrostatic pressure by drawing actuation fluid from the reserve volume to the tool volume through a check valve. To set the hanger, a plug is engaged on a seat in the tool, tubing pressure is applied behind the engaged plug, and the seat is unlocked. With more applied pressure, the piston moves, reduces the tool volume, and intensifies pressure of the clean fluid communicated to the hanger's setting mechanism. Over-pressure can be handled by a venting valve.

A downhole tool includes a top sub-assembly configured to connect to a downhole conveyance that is operable to run the tool into a wellbore formed from a terranean surface to a subterranean formation; a housing coupled at an uphole end to the top sub-assembly, the housing defining an interior volume; a vacuum positioned in the interior volume and configured to generate a fluid suction; a debris chamber fluidly coupled to the vacuum and positioned in the interior volume; a nozzle coupled at a downhole end of the housing, the nozzle including one or more openings; and a controller communicably coupled to the vacuum and configured to perform operations including activating the vacuum to generate the fluid suction to circulate wellbore debris through the vacuum and into the debris chamber.

A system and method set a liner hanger in a borehole by actuating a hydraulic setting mechanism on the hanger to engage slips in the borehole. A setting tool runs the hanger into position. A reserve volume of the tool holds a clean fluid separate from the borehole. A piston of the tool has a tool volume for the fluid. During run in, pressure in the tool volume is balanced to hydrostatic pressure by drawing actuation fluid from the reserve volume to the tool volume through a check valve. To set the hanger, a plug is engaged on a seat in the tool, tubing pressure is applied behind the engaged plug, and the seat is unlocked. With more applied pressure, the piston moves, reduces the tool volume, and intensifies pressure of the clean fluid communicated to the hanger's setting mechanism. Over-pressure can be handled by a venting valve.