A technique facilitates control over at least one flow control assembly position to control fluid with respect to a tubing string. The flow control assembly is disposed along the tubing string and comprises a flow control valve and a motor to control the operational position of the flow control valve. The flow control valve may comprise a plunger and a seal system to provide a seal between the plunger and a surrounding structure. Additionally, the flow control valve comprises a pressure balanced system. The pressure balanced system serves to balance pressure acting on the plunger such that the motor is able to move the plunger by simply overcoming friction of the seal system without overcoming a pressure differential otherwise acting on the plunger.

Downhole apparatus comprises first and second tools for location in a tubing string. The first tool has a first seat of a first diameter and the second tool has a second seat of a second diameter larger than the first diameter. First and second activating devices are provided for use in activating the respective first and second tools. The first activating device includes a first activating profile having an extended diameter larger than the first diameter and smaller than the second diameter and a retracted diameter smaller than the first diameter. The second activating device includes a second activating profile having an extended diameter larger than the second diameter and a retracted diameter smaller than the first diameter.

Downhole apparatus comprises first and second tools for location in a tubing string. The first tool has a first seat of a first diameter and the second tool has a second seat of a second diameter larger than the first diameter. First and second activating devices are provided for use in activating the respective first and second tools. The first activating device includes a first activating profile having an extended diameter larger than the first diameter and smaller than the second diameter and a retracted diameter smaller than the first diameter. The second activating device includes a second activating profile having an extended diameter larger than the second diameter and a retracted diameter smaller than the first diameter.

A tool string carrying an external tool, such as a liner hanger, on a release mechanism is lowered into the wellbore. Interlocking lugs and J-slot profile, defined between the exterior surface of the mandrel and interior surface of the release mechanism, allow relative movement of release mechanism and mandrel without releasing the release mechanism. The relative movement allows mechanical operation of a valve or other tool positioned below the release mechanism. Weight-down and rotation of the tool string and mandrel actuates the lower valve assembly by turning a sleeve into alignment with cooperating members of the mandrel. The sleeve, no longer constrained, moves longitudinally in response to a biasing mechanism. Movement of the sleeve allows closure of the valve. After actuation of the valve tool, further weight-down releases the release mechanism from the carried tool.

A flexible collet on a subterranean tool has sacrificial soft components to protect seal bores through which the collets have to compress to get through. The sacrificial components can be replaced when the tool is removed to the surface. In one embodiment, threaded fasteners are used alone or with washers for height adjustment such that the heads of the fasteners which are softer than the seal bore material ride on the seal bore and take the wear. The tool can ultimately be used to latch into shifting sleeves to move such sleeves to open or close wall ports. Alternatively axial ridges with beveled profile ends can be used or rolling members such as wheels or balls can be used to keep sharp edges off the seal bore. EDM method can be used to create multiple fingers with an axial ridge profile and rounded end transitions.

A flexible collet on a subterranean tool has sacrificial soft components to protect seal bores through which the collets have to compress to get through. The sacrificial components can be replaced when the tool is removed to the surface. In one embodiment, threaded fasteners are used alone or with washers for height adjustment such that the heads of the fasteners which are softer than the seal bore material ride on the seal bore and take the wear. The tool can ultimately be used to latch into shifting sleeves to move such sleeves to open or close wall ports. Alternatively axial ridges with beveled profile ends can be used or rolling members such as wheels or balls can be used to keep sharp edges off the seal bore. EDM method can be used to create multiple fingers with an axial ridge profile and rounded end transitions.

A method for logging in a cased well is disclosed. The method includes receiving well data comprising an orientation of the cased well, selecting a logging while levitating (LWL) assembly type based on the well data, running the LWL assembly into the well to a start depth, and activating the LWL assembly based on a downhole condition so that the LWL assembly levitates in a center of the cased well, wherein the activated LWL assembly moves downhole in the cased well while levitating. The method further includes determining whether the LWL assembly has reached a target depth and performing logging in the cased well while the LWL assembly is levitating in the cased well when the target depth is reached.

A roller tool 1 that can be connected into a string for deployment into an oil or gas well includes at least two rollers or wheels 10 located on each side of the roller tool 1, with axes of rotation that are perpendicular to the axis of the roller tool 1. The roller tool further includes at least two interconnecting tubular portions, where one tubular portion 41 comprises a mandrel 45 that connects to another tubular portion 42. An annular hub 20 is fitted over the mandrel 45 and the rollers 10 are connected onto the hub 20. The tubular portions 41, 42 comprise circumferential sleeve sections 56a, 56b that partially extend over the rollers 10 and resist detachment of the rollers 10 from the roller tool 1. The roller tool 1 can aid passage of a string through a well by holding the string away from the walls of the well and reducing frictional contact.

A method of actuating a downhole component comprises positioning a magnetic positioning tool adjacent an actuable component within a wellbore, where the magnetic positioning tool comprises a plurality of magnets arranged in a first position, transitioning the plurality of magnets from the first position to a second position, detecting the plurality of magnets using a sensor associated with the actuable component, generating a signal indicative of the plurality of magnets being in the second position, and actuating the actuable component within the wellbore in response to the signal.

Some examples of the present disclosure relate to a method for washing an annulus that at least partially surrounds a casing in a well. The method comprises locating a tool inside a wellbore casing, and flowing a washing fluid from an injection aperture on the tool and into the annulus via a first casing aperture in the casing. An inflow region of the casing is created having a reduced pressure relative to the annulus, and the method involves flowing the washing fluid from the annulus and into the inflow region of the casing through a second casing aperture in the casing.