Abstract: A well tool can include a magnetic sensor having opposite sides, and a magnetic shield that conducts an undesired magnetic field from one side to the other side of the sensor. Another well tool can include a magnetic sensor in a housing, the sensor having opposite longitudinal sides relative to a housing longitudinal axis, and a magnetic shield interposed between the housing and each of the opposite longitudinal sides of the magnetic sensor. Another well tool can include at least two magnetic sensors, one magnetic sensor sensing a magnetic field oriented orthogonal to the housing longitudinal axis, and another magnetic sensor sensing a magnetic field oriented parallel to the longitudinal axis, and a magnetic shield interposed between a housing and each of opposite longitudinal sides of the magnetic sensors.

Abstract: A method of servicing a wellbore comprising providing a flowable component comprising syntactic foam, communicating the flowable component into a wellbore, and allowing the flowable component to be removed from the wellbore.

Abstract: A magnetic system for determining the location of a wellbore component in a first string relative to a wellbore component in a second string. The system includes a circumferentially distributed array of magnets positioned in the first string that is operable to produce a magnetic field in the wellbore proximate the location of the array of magnets. A magnetic field detector is operably associated with the second string and is operable to detect a magnetic signature of the magnetic field. One of the first and second strings is stationary within the wellbore. The other of the first and second strings is moveable in the wellbore such that the magnetic field detector is moveable relative to the magnetic field and such that when the magnetic field detector identifies the magnetic signature, the location of the array of magnets is correlated with the magnetic field detector.

Abstract: A system for use with a subterranean well can include a tubular string with a fluid discharge apparatus, the fluid discharge apparatus including a curved flow path which directs a fluid to flow less toward a structure external to the tubular string. A fluid discharge apparatus can include a generally tubular housing having a longitudinal axis, and at least one curved flow path which directs fluid to flow more parallel to the longitudinal axis from an interior of the housing to an exterior of the housing. A method of mitigating erosion of a structure external to a discharge port in a well can include directing a fluid to flow through a curved flow path, thereby reducing impingement of the fluid on the structure in the well.

Abstract: A wellbore isolation device comprising: a first material, wherein the first material: (A) is a metal or a metal alloy; and (B) partially dissolves when an electrically conductive path exists between the first material and a second material and at least a portion of the first and second materials are in contact with an electrolyte; and an electrolytic compound, wherein the electrolytic compound dissolves in a fluid located within the wellbore to form free ions that are electrically conductive. A method of removing the wellbore isolation device comprises: placing the wellbore isolation device into the wellbore; and allowing at least a portion of the first material to dissolve.

Abstract: A method of using a wellbore isolation device comprises: introducing the wellbore isolation device into the wellbore, wherein the isolation device comprises: (A) a matrix, wherein the matrix has a phase transition temperature less than or equal to the bottomhole temperature of the wellbore; and (B) at least one reinforcement area, wherein the reinforcement area: (i) comprises at least a first material, wherein the first material undergoes galvanic corrosion; and (ii) has a greater tensile strength and/or shear strength than the matrix.

Abstract: Methods of actuating a well tool can include releasing chemical energy from at least one portion of a reactive material, thermally expanding a substance in response to the released chemical energy, and applying pressure to a piston as a result of thermally expanding the substance, thereby actuating the well tool, with these steps being repeated for each of multiple actuations of the well tool. A well tool actuator can include a substance contained in a chamber, one or more portions of a reactive material from which chemical energy is released, and a piston to which pressure is applied due to thermal expansion of the substance in response to each release of chemical energy. A well tool actuator which can be actuated multiple times may include multiple portions of a gas generating reactive material, and a piston to which pressure is applied due to generation of the gas.

Abstract: A wellbore isolation device includes a substance; and a pH maintainer, wherein the pH maintainer maintains the pH of a wellbore fluid surrounding the isolation device at a desired pH or range of pH values for a desired period of time, and wherein the substance is capable of decomposing at the desired pH or range of pH values. A method of removing the wellbore isolation device includes placing the isolation device into the wellbore; and causing or allowing at least a portion of the substance to decompose.

Abstract: A wellbore isolation device comprising: a material that dissolves via corrosion when in contact with a wellbore fluid, a surface of the material, wherein the surface of the material is altered via a surface treatment, and wherein the altered surface delays corrosion of the material for a desired amount of time. A method of removing the wellbore isolation device comprising: contacting or allowing the wellbore isolation device to come in contact with a wellbore fluid; and causing or allowing at least the portion of the material to dissolve.

Abstract: A magnetic system for determining an operating position of a downhole tool. The system includes an array of magnets operable to produce a magnetic field that is operably associated with a stationary component of the downhole tool. A moveable component of the downhole tool has at least first and second positions relative to the stationary component. In the first position, the moveable component has a first degree of interference with the magnetic field. In the second position, the moveable component has a second degree of interference with the magnetic field. A magnetic field detector is operable to be run into the wellbore and moved relative to the downhole tool such that the position of the moveable component relative to the stationary component is determined by detection of a magnetic signature produced by the moveable component and the array of magnets.

Abstract: A method of plugging a flow passage in a well can include conveying a plug into an isolation tool in the well, and then contracting a plug seat of the isolation tool. An isolation tool for plugging a flow passage in a subterranean well can include a piston, and a longitudinally displaceable plug seat. The plug seat longitudinally displaces in response to displacement of the piston. Another method of plugging a flow passage can include conveying a plug into an isolation tool in the well, and then longitudinally displacing a plug seat of the isolation tool, thereby radially contracting the plug seat.

Abstract: A method of performing an operation in a wellbore comprising: introducing a tool into the wellbore, wherein the tool comprises: (A) a mandrel comprising a port; and (B) a plug, wherein the plug is located within the port, and wherein the plug comprises at least a first material, wherein the first material partially or wholly dissolves via corrosion; introducing a cement composition into an annulus located between the outside of the tool at least at the location of the port and the inside of the wellbore; and causing or allowing at least a portion of the first material to dissolve, wherein the step of causing or allowing is performed after the step of introducing the cement composition.

Abstract: A wellbore isolation device comprising: a first material, wherein the first material: (A) is a metal or a metal alloy; and (B) partially dissolves when an electrically conductive path exists between the first material and a second material and at least a portion of the first and second materials are in contact with an electrolyte; and an electrolytic compound, wherein the electrolytic compound dissolves in a fluid located within the wellbore to form free ions that are electrically conductive. A method of removing the wellbore isolation device comprises: placing the wellbore isolation device into the wellbore; and allowing at least a portion of the first material to dissolve.

Abstract: At least a portion of a wellbore isolation device consists essentially of: a metal alloy, wherein the metal alloy: (A) comprises magnesium at a concentration of at least 50% by volume of the metal alloy; and (B) at least partially dissolves in the presence of an electrolyte. A method of removing the wellbore isolation device comprises: contacting or allowing the wellbore isolation device to come in contact with an electrolyte; and allowing at least a portion of the metal alloy to dissolve.

Abstract: A method of activating a downhole tool can include configuring the tool having an electrical power source, an electrical load, control circuitry which controls the electrical load, and a switch which selectively permits current flow between the power source and the circuitry, and generating electricity, thereby causing the switch to permit current flow between the power source and the circuitry. A downhole tool can include an electrical power source, an electrical load, control circuitry, a switch which selectively permits current flow between the power source and the circuitry, and a generator. Another method can include displacing a fluid and/or an object at the tool, generating electricity in response to the displacing, permitting current flow between an electrical power source and a control circuitry in response to the generating and, after the permitting and in response to detection of a predetermined signal, the circuitry causing activation of an electrical load.

Abstract: Switching a downhole tool between a first operation mode, a second operation mode, and a third operation mode, operation modes may include a sleep mode in which the downhole tool consumes less energy, a twilight mode in which the downhole tool consumes more energy than in sleep mode and/or may perform limited functions, and an awake mode in which the downhole tool consumes more energy than in the sleep mode or in the twilight mode and may perform additional tool functions.

Abstract: A wellbore isolation device comprising: a first material, wherein the first material: (A) is a metal or a metal alloy; and (B) partially dissolves when an electrically conductive path exists between the first material and a second material and at least a portion of the first and second materials are in contact with an electrolyte; and an electrolytic compound, wherein the electrolytic compound dissolves in a fluid located within the wellbore to form free ions that are electrically conductive. A method of removing the wellbore isolation device comprises: placing the wellbore isolation device into the wellbore; and allowing at least a portion of the first material to dissolve.

Abstract: A wellbore isolation device comprises: a first material and a second material, wherein the first material and the second material form a galvanic couple and wherein the first material is the anode and the second material is the cathode of the galvanic couple, and wherein the second material is a fiber or a plurality of fibers. A method of removing the wellbore isolation device comprises: contacting or allowing the wellbore isolation device to come in contact with an electrolyte; and causing or allowing at least a portion of the first material to dissolve.

Abstract: A wellbore isolation device comprises a first material and pieces of a second material, wherein the first material: is a metal or a metal alloy; forms a matrix of the portion of the wellbore isolation device; and partially or wholly dissolves when an electrically conductive path exists between the first material and the second material and at least a portion of the first and second materials are in contact with the electrolyte, wherein the pieces of the second material: are a metal or metal alloy; and are embedded within the matrix of the first material; wherein the first material and the second material form a galvanic couple and wherein the first material is the anode and the second material is the cathode of the couple. The isolation device can also include a bonding agent for bonding the pieces of the second material into the matrix of the first material.

Abstract: A production sleeve assembly for use in a wellbore comprises a wellbore tubular, a plurality of fluid pathways configured to provide fluid communication within the downhole component, a plurality of electronic actuators configured to selectively provide fluid communication through one or more of the plurality of fluid pathways, and at least one sensor coupled to the plurality of electronic actuators. One or more of the plurality of electronic actuators are configured to selectively actuate to allow or prevent fluid flow through a corresponding fluid pathway of the plurality of fluid pathways in response to the at least one sensor receiving a suitable signal.