Abstract: A monitoring well installation comprising metallic casing (2) running down from the surface into a borehole and a sealing material plug (6) provided downhole for blocking the interior of the casing and sealing the borehole against the egress of fluid from a zone below the plug. There is an axial spacing (2A) between adjacent casing portions (2) in the region of the plug (6) such that there is an uncased length of borehole in which the material of the plug seals against the formation. There is provided a sensing tool (3) located below the plug (6) for sensing at least one parameter below the plug (6) and a communication arrangement (3, 4, 5) for use in transmitting data from the sensing tool (3) towards the surface. The communication arrangement comprises across plug communication apparatus (5) for facilitating transmission of signals carrying data across the plug (6) towards the surface.

Abstract: A well installation comprising downhole power delivery apparatus for delivering electrical power from a surface power source S to a downhole tool T. The well installation comprises downhole metallic structure (2) running down into a borehole. The apparatus comprises an electrical cable (3) for carrying electrical power from the surface power source S, a power transfer arrangement (4) and a power pick up arrangement (5). The cable 3 runs down into the borehole together with the metallic structure (2) to the power transfer arrangement (4) which is provided at a first downhole location for transferring electrical power carried by the electrical cable (3) onto the downhole metallic structure (2) for onward conduction. The power pick up arrangement (5) is provided at a second downhole location, spaced from the first, for picking up electrical power from the downhole metallic structure (2) for supply to the downhole tool T.

Abstract: A downhole power delivery system for use in a well comprising downhole metallic pipe (2) running in a borehole of the well with a downhole sealing plug (31) provided in a bore or annulus at least partly defined by the downhole metallic pipe. The power delivery system comprising below plug apparatus (5) located in the borehole below the plug (31) including a downhole device (53) requiring electrical power and downhole power supply apparatus (6) located in the borehole above the plug (31). The power supply apparatus (6) comprises at least one battery (64) for powering the downhole device and the downhole power supply apparatus (6) and below plug apparatus (5) being arranged for delivering electrical power from the downhole power supply apparatus (6) to the downhole device (53) across the downhole sealing plug (31).

Abstract: Downhole electrical energy harvesting and communication in systems for well installations having metallic structure carrying electric current, for example CP current. In some instances there is a harvesting module (4) electrically connected to the metallic structure (2) at a first location and to a second location spaced from the first location, the first and second locations being chosen such that, in use, there is a potential difference therebetween due to the electric current flowing in the structure (2); and the harvesting module (4) being arranged to harvest electrical energy from the electric current. In addition or alternatively, there may be communication apparatus (4, 5, 6) for communication by modulation of the current, for example CP current, in the metallic structure (2).

Abstract: Downhole electrical energy harvesting and communication in systems for well installations having metallic structure carrying electric current, for example CP current. In some instances there is a harvesting module (4) electrically connected to the metallic structure (2) at a first location and to a second location spaced from the first location, the first and second locations being chosen such that, in use, there is a potential difference therebetween due to the electric current flowing in the structure (2); and the harvesting module (4) being arranged to harvest electrical energy from the electric current. In addition or alternatively, there may be communication apparatus (4, 5, 6) for communication by modulation of the current, for example CP current, in the metallic structure (2).

Abstract: Downhole electrical energy harvesting and communication in systems for well installations having metallic structure carrying electric current, for example CP current. In some instances there is a harvesting module (4) electrically connected to the metallic structure (2) at a first location and to a second location spaced from the first location, the first and second locations being chosen such that, in use, there is a potential difference therebetween due to the electric current flowing in the structure (2); and the harvesting module (4) being arranged to harvest electrical energy from the electric current. In addition or alternatively, there may be communication apparatus (4, 5, 6) for communication by modulation of the current, for example CP current, in the metallic structure (2).

Abstract: Downhole electrical energy harvesting and communication in systems for well installations having metallic structure carrying electric current, for example CP current. In some instances there is a harvesting module (4) electrically connected to the metallic structure (2) at a first location and to a second location spaced from the first location, the first and second locations being chosen such that, in use, there is a potential difference therebetween due to the electric current flowing in the structure (2); and the harvesting module (4) being arranged to harvest electrical energy from the electric current. In addition or alternatively, there may be communication apparatus (4, 5, 6) for communication by modulation of the current, for example CP current, in the metallic structure (2).

Abstract: Apparatus (100) for use in sensing temperature in a wellbore, comprising: tubing (110) comprising a plurality of temperature sensor modules (120, 320, 420, 520, 620, 720) provided at locations along the inside of the tubing, said temperature sensor modules comprising temperature sensors (321, 421) provided at least in part by at least one semiconductor element having electrical properties that vary with temperature; an electrical network (115) configured to electrically connect to the semiconductor elements to in use allow measuring of the respective electrical properties of the semiconductor elements to infer a thermal characteristic of the semiconductor element; and at least one control module (130, 330, 430) electrically connected to multiple temperature sensor modules, via the electrical network, and configured to receive and process an electrical signal associated with the temperature sensor modules to enable inference of the temperature of the semiconductor elements and the environment to which the tubi

Abstract: A method to manipulate a well, comprising running an apparatus (60a) having a container (68a) with a volume of gas at a higher pressure than a surrounding portion of the well. The well is isolated, and a wireless control signal, such as an electromagnetic or acoustic signal, is sent to operate a valve assembly (62a) to selectively allow or resist fluid exit from a portion of the container (68a), via a port (61a). Some of the pressurised gas may itself be expelled in to the surrounding portion of the well, or it may be used to drive a fluid out of the container, such as an acid.

Abstract: A method of monitoring a reservoir comprising setting at least one barrier in a well separating it into upper and lower isolated sections. A perforating gun or other perforating device is provided in the lower isolated section, along with a control mechanism, wireless communication device and a pressure sensor. After the barrier is set, the perforating gun is activated in order to create at least one perforation between the well and a surrounding reservoir. The well, or part of it, is suspended or abandoned but the pressure is still monitored and a wireless, preferably acoustic or electromagnetic, data signal is transmitted from the lower isolated section to above the barrier. Data from the suspended/abandoned part of the well may be used to infer characteristics of the reservoir so that it may be exploited more appropriately especially through another well.

Abstract: Apparatus for use in sensing temperature in a wellbore, comprising: tubing comprising a plurality of temperature sensor modules provided at locations along the inside of the tubing, said temperature sensor modules comprising temperature sensors provided at least in part by at least one resistive element having electrical properties that vary with temperature; an electrical network configured to electrically connect to the resistive elements to in use allow measuring of the respective electrical properties of the resistive elements to infer a thermal characteristic of the resistive element; and at least one control module electrically connected to multiple temperature sensor modules, via the electrical network, and configured to receive and process an electrical signal associated with the temperature sensor modules to enable inference of the temperature of the resistive elements and the environment to which the tubing is exposed at the location of that resistive element.

Abstract: A method to manipulate a well comprising providing an apparatus (60) in a well (14) below a packer (22) or other annular sealing device, the apparatus comprising a container (68) having a volume of gas which is sealed at the surface and nm into the well, such that the pressure in the container (68) is at a lower pressure than the surrounding well. When the apparatus is below the packer, a wireless control signal, is sent to operate a valve assembly (62) to selectively allow fluid to enter the container whereby at least 50 litres of fluid is drawn into the container. In this way, the apparatus can be used independent of perforating guns, to clear perforations or other areas in the well or may be used for a variety of tests such as an interval test, drawdown test or a connectivity test such as a pulse or interference test.

Abstract: Apparatus (100) for use in sensing temperature along a wellbore, comprising: tubing (110) comprising a plurality of temperature sensor modules (120) provided at locations along the inside of the tubing, having electrical properties that vary with temperature; and an electrical network (115) comprising a plurality of wires and said plural temperature sensor modules, wherein the wires and plural temperature sensor modules are configured as a matrix by which the wires comprise a first group of wires and a second, different group of wires and each wire of the first group is electrically connected to each wire of the second group once, by different temperature sensor modules, such that each temperature sensor module can be individually electrically connected by a pair of wires comprising a first wire from the first group and a second wire from the second group.

Abstract: A method of pressure testing a casing system (12) comprising deploying an apparatus (110) with a container (68) formed from drill pipe or production tubing, on a string of drill pipe or production tubing into a well, such that a port (61) thereof is provided in an isolated section of the well. The isolated section of the well has a higher pressure than the pressure of a gas sealed in the container (68). The port (61) is opened and pressure in the isolated section is monitored to assess its integrity. Communication with the apparatus is achieved by wireless means sending pressure data, control signals for controlling the port and/or other data or commands.

Abstract: A method to manipulate a well, comprising running an apparatus having a container and an electrically powered pump into the well. The well is isolated, and a wireless control signal, such as an electromagnetic or acoustic signal, is sent to operate the pump in response in order to pump fluid from within the container to the surrounding portion of the well. The apparatus may comprise a pressure balancing means, such as a floating piston between two ports of the container, and/or an in well charging means.

Abstract: A downhole apparatus and method for expelling fluid which comprises a container defining a void which is separated into three separate sections by a floating piston and control member, each having a dynamic seal. A portion of the container defining one of the void sections has a different cross-sectional area than the portion of the container defining another void section. In use, a fluid to be expelled is provided in one void section, and a reduced pressure (compared to the well) is sealed in another void section. The apparatus also comprises a wireless electromagnetic or acoustic receiver. When a signal is received by the wireless receiver to activate the apparatus, a valve or other mechanism maybe activated to release the floating piston and connected control member such that the lower pressure void and differing cross-sectional areas of the container drives and expels fluid out of the apparatus.

Abstract: A well comprising a pressure activated device exposed to pressure in an annulus above a barrier between an upper tubular and the borehole. An acoustic or electromagnetic (EM) transmitter is coupled to the pressure activated device and configured to transmit a control signal to a respective receiver below the barrier for controlling a valve. In the event of an emergency, certain embodiments allow the pressure in the annulus to be quickly dropped, activating the transmitter to close the valve below the barrier, thus isolating the well below the barrier. A variety of default states may be programmed into the transmitter, such as transmitting a ‘stay-open’ signal to the receiver controlling the valve, which is configured to close if this signal is not received. A further EM or acoustic transmitter may be coupled to the valve to send information from below the barrier to above the barrier, such as pressure data or valve status.

Abstract: A well (10) comprising a packer apparatus, the packer apparatus comprising: a packer (16) and an activation mechanism; wherein the activation mechanism comprises an expansion mechanism for expanding the packer (16) and a wireless receiver (360) optionally a transceiver. For certain embodiments the wireless receiver may be acoustic and/or electromagnetic. The receiver is adapted to receive a wireless control signal and control the activation mechanism and wherein the packer apparatus is provided downhole in any one of the following locations, (i) on a production tubing; (ii) in a casing annulus between two different casing strings; (iii) between the casing and formation; (iv) on a sub-assembly within an uncased section of the well and (v) on a drill string.

Abstract: A safety mechanism comprising: an obstructing member moveable between a first position where fluid flow is permitted, and a second position where fluid flow is restricted preferably blocked; a movement mechanism; and a wireless receiver, often an acoustic transceiver, adapted to receive a wireless signal; wherein the movement mechanism is operable to move the obstructing member from one of the first and second positions to the other of the first and second positions in response to a change in the signal being received by the wireless receiver. Embodiments of the invention thus provide a safety mechanism for a well such as a valve, packer, plug or sleeve, which can be operated wirelessly and so may allow operation of safety mechanisms in a well even when emergency situations have occurred.

Abstract: A well comprising: (a) a safety mechanism, the safety mechanism comprising: (i) an obstructing member moveable between a first position where fluid flow is permitted, and a second position where fluid flow is restricted; (ii) a movement mechanism; (iii) and a wireless receiver, adapted to receive a wireless signal; wherein the movement mechanism is operable to move the obstructing member from one of the first and second positions to the other of the first and second positions in response to a change in the signal being received by the wireless receiver; (b) sensors to detect a parameter in the well, in the vicinity of the safety mechanism; wherein a sensor is provided above and a sensor is provided below the safety mechanism. Embodiments of the invention have acoustic and/or electromagnetic receivers or transceivers.