Abstract: A system or apparatus for use in downhole communication or detection comprises a downhole arrangement defining a throughbore and primary and secondary elements. One of the primary and secondary elements is provided on the downhole arrangement and the other of the primary and secondary elements is provided in the throughbore. The primary and secondary elements are configurable for coupling of an electromagnetic field therebetween. The primary or secondary element which is provided in the throughbore may be provided on a tool such as a shifting tool which is deployable through the throughbore. The secondary element may be configured to provide the electromagnetic field coupled between the first and second elements with one or more characteristic features. The system may be configured for use, in particular though not exclusively, for communicating information to and/or from a downhole tool in an oil or gas well.

Abstract: A system for isolating a wellbore having a fluid flow passage extending from surface to a subterranean location has a first, downhole, valve and a second, uphole, valve. The downhole valve is located in the wellbore at a first subterranean location and the uphole valve is located in the wellbore at a second subterranean location spaced from the first valve. Downhole valve is operable between a first configuration permitting access through the flow passage and a second, well isolation, configuration isolating the flow passage below the valve. Uphole valve is operable between a first configuration permitting access therethrough and a second, isolation, configuration providing an isolated or isolatable volume between the first and second valves. A pressure sensor disposed in the isolated volume between the downhole valve and the uphole valve and, in use, permits a pressure in the isolated volume to be measured and/or communicated to a remote location.

Abstract: A spool of optical fibre comprises a spool axis and a length of optical fibre wound around the spool axis to form a plurality of wrap segments arranged axially along the spool axis, wherein adjacent wrap segments partially overlap in the axial direction. Each wrap segment comprises a first wrap layer wound in a first axial direction over a first axial distance, and a second wrap layer wound over the first wrap layer in a reverse second axial direction over a second axial distance greater than the first axial distance, the optical fibre extending from the second wrap layer of one wrap segment to the first wrap layer of an adjacent wrap segment. The spool may be mounted in a device such that the optical fibre can be despooled and deployed from the device.

Abstract: A valve assembly (10) comprises a flow path extending from an assembly inlet (20) to an assembly outlet (22), a valve (24a/26a) arranged within the flow path and a filter assembly arranged within the flow path between the assembly inlet and the valve. The filter assembly comprises a filter chamber defining a particle settlement region, a filter chamber inlet for facilitating inflow of a fluid into the chamber, and a filter chamber outlet for facilitating outflow of fluid from the chamber towards the valve, wherein the filter chamber outlet includes a particle filter.

Abstract: A valve assembly comprises an actuation fluid inlet, an actuation fluid outlet and a valve member moveable between a closed position in which the actuation fluid outlet is closed, and an open position in which the actuation fluid outlet is opened. A locking arrangement is provided for locking the valve member in its closed position, wherein the locking arrangement is operable in response to a first predetermined fluid pressure event associated with at least the actuation fluid inlet to release the locking arrangement to permit the valve member to be moved to its open position in response to a second subsequent predetermined fluid pressure event associated with at least the actuation fluid inlet.

Abstract: A deployable device including a deployable member. The deployable member includes an optical fibre. The deployable member is stowed at the device in a first wound configuration and arranged to be deployed from the device to a second unwound configuration within a well. In examples, the deployable device is configured such that, when unwound, the deployable member has a propensity to adhere to a wall within the well. In examples, the deployable member includes at least a first length and second length, the first and second lengths having different mechanical properties.

Abstract: A system or apparatus for use in downhole communication or detection comprises a downhole arrangement defining a throughbore and primary and secondary elements. One of the primary and secondary elements is provided on the downhole arrangement and the other of the primary and secondary elements is provided in the throughbore. The primary and secondary elements are configurable for coupling of an electromagnetic field therebetween. The primary or secondary element which is provided in the throughbore may be provided on a tool such as a shifting tool which is deployable through the throughbore. The secondary element may be configured to provide the electromagnetic field coupled between the first and second elements with one or more characteristic features. The system may be configured for use, in particular though not exclusively, for communicating information to and/or from a downhole tool in an oil or gas well.

Abstract: A system or apparatus for use in downhole communication or detection comprises a downhole arrangement defining a throughbore and primary and secondary elements. One of the primary and secondary elements is provided on the downhole arrangement and the other of the primary and secondary elements is provided in the throughbore. The primary and secondary elements are configurable for coupling of an electromagnetic field therebetween. The primary or secondary element which is provided in the throughbore may be provided on a tool such as a shifting tool which is deployable through the throughbore. The secondary element may be configured to provide the electromagnetic field coupled between the first and second elements with one or more characteristic features. The system may be configured for use, in particular though not exclusively, for communicating information to and/or from a downhole tool in an oil or gas well.

Abstract: A method of actuating at least one of a plurality of downhole tools (10) connected to at least one hydraulic fluid line (L1, L2) is disclosed. The method includes the steps of: a) providing each of the downhole tools with a control unit (20) comprising a timer which permits fluid communication between the at least one hydraulic fluid line and the downhole tool during a window of time; and b) controlling the pressure in the at least one hydraulic fluid line for at least a sufficient period of time required to at least actuate the said downhole tool, wherein the said sufficient period of time coincides at least partially with the said window of time.

Abstract: A screen assembly, such as a downhole/sand screen assembly, comprising first and second screen portions or screens longitudinally coupled together, wherein there is provided a fluid flow path between the first and second screen portions or screen. Optionally, the first and second sleeves are coupled or connected by a centralizer or further sleeve or screen, and/or optionally by or via first and second support ring.

Abstract: A downhole arrangement (32) comprises first (34) and second (41) members, a lock profile (4) fixed relative to one of the first and second members, and a lock member (10) for engaging the at least one lock profile. A release member (40) is provided which is moveable to selectively lock the lock member in engagement with the lock profile so as to selectively secure the second member relative to the first member. Such a downhole arrangement may permit a releasable connection between the first and second members.

Abstract: A downhole actuator (30) comprises a tubular housing (34) which includes an indexing profile (42) on an inner surface thereof, and an indexing sleeve (46) mounted within the housing (34). The indexing sleeve (46) comprises an engaging arrangement including first and second axially spaced engagement members (52, 54) which cooperate with the indexing profile (42) of the housing (34) to be sequentially engaged by an actuation object (48) passing through a central bore (50) of the indexing sleeve (46) to drive the indexing sleeve (46) one discrete step of movement through the housing (34) towards an actuation site.

Abstract: A system or apparatus for use in downhole communication or detection comprises a downhole arrangement defining a throughbore and primary and secondary elements. One of the primary and secondary elements is provided on the downhole arrangement and the other of the primary and secondary elements is provided in the throughbore. The primary and secondary elements are configurable for coupling of an electromagnetic field therebetween. The primary or secondary element which is provided in the throughbore may be provided on a tool such as a shifting tool which is deployable through the throughbore. The secondary element may be configured to provide the electromagnetic field coupled between the first and second elements with one or more characteristic features. The system may be configured for use, in particular though not exclusively, for communicating information to and/or from a downhole tool in an oil or gas well.

Abstract: A screen assembly, such as a downhole/sand screen assembly, comprising first and second screen portions or screens longitudinally coupled together, wherein there is provided a fluid flow path between the first and second screen portions or screen. Optionally, the first and second sleeves are coupled or connected by a centralizer or further sleeve or screen, and/or optionally by or via first and second support ring.

Abstract: A downhole tool (32) comprises a tool housing (34) defining a central bore (35) and including a fluid port (20), and a valve member (40) mounted within the housing (34) and being movable from a closed position in which the fluid port (20) is blocked to an open position in which the fluid port (20) is opened. The tool (32) further comprises a catching arrangement (41) mounted within the housing (34) and comprising one or more radially movable seat members (106), and being configurable from a free configuration in which the seat members (106) permit an object (48) to pass through the tool (32), to a catching configuration in which the seat members (106) catch an object (48) passing through the tool (32).

Abstract: A downhole tool (32) comprises a tool housing (34) defining a central bore (35) and including a fluid port (20), and a valve member (40) mounted within the housing (34) and being moveable from a closed position in which the fluid port (20) is blocked to an open position in which the fluid port (20) is opened. The tool (32) further comprises a catching arrangement (41) mounted within the housing (34) and comprising one or more radially moveable seat members (106), and being configurable from a free configuration in which the seat members (106) permit an object (48) to pass through the tool (32), to a catching configuration in which the seat members (106) catch an object (48) passing through the tool (32).

Abstract: A downhole actuator (30) comprises a tubular housing (34) which includes an indexing profile (42) on an inner surface thereof, and an indexing sleeve (46) mounted within the housing (34). The indexing sleeve (46) comprises an engaging arrangement including first and second axially spaced engagement members (52, 54) which cooperate with the indexing profile (42) of the housing (34) to be sequentially engaged by an actuation object (48) passing through a central bore (50) of the indexing sleeve (46) to drive the indexing sleeve (46) one discrete step of movement through the housing (34) towards an actuation site.

Abstract: The switching device comprises an electronic switch embedded within a downhole tool (100) and an activator for remote switching of the electronic switch. The activator may be a handheld unit that is used at the surface of the wellbore by an operator or may be a wireline run unit. The activator permits wireless and contactless activation of the electronic switch without the need for mechanical switches which could provide a point of failure for the downhole tool. The electronic switch comprises an electronics module and a power source such as one or more batteries wherein in the active configuration, the switch can allow electrical connection between the electronics module and the power source and in the inactive configuration, the switch prevents electrical connection between the electronics module and the power source.

Abstract: A downhole tool (32) comprises a tool housing (34) defining a central bore (35) and including a fluid port (20), and a valve member (40) mounted within the housing (34) and being moveable from a closed position in which the fluid port (20) is blocked to an open position in which the fluid port (20) is opened. The tool (32) further comprises a catching arrangement (41) mounted within the housing (34) and comprising one or more radially moveable seat members (106), and being configurable from a free configuration in which the seat members (106) permit an object (48) to pass through the tool (32), to a catching configuration in which the seat members (106) catch an object (48) passing through the tool (32).

Abstract: A method of actuating at least one of a plurality of downhole tools connected to at least one hydraulic fluid line is disclosed. The method includes the steps of:— a) providing each of the downhole tools with a control unit comprising a timer which permits fluid communication between the at least one hydraulic fluid line and the downhole tool during a window of time; and b) controlling the pressure in the at least one hydraulic fluid line for at least a sufficient period of time required to at least actuate the said downhole tool, wherein the said sufficient period of time coincides at least partially with the said window of time.