Abstract: The present disclosure is directed to the filtering and collection of downhole fluids. An example system to filter and sample downhole fluids includes a first sampling chamber that includes one or more cone-shaped filters to receive downhole fluid, filter the downhole fluid, and store the downhole fluid, a second sampling chamber, a spool valve to allow the downhole fluid to flow into the first sampling chamber in a first position and to redirect the downhole fluid to the second sampling chamber or a base block in a second position, and a setting line to selectively move the spool valve from the first position to the second position.

Abstract: A flow stop valve (200, 300, 400) for placement in a downhole tubular operating in a dual fluid density system, wherein the flow stop valve is arranged such that it is in communication with a pressure difference between one of: fluid outside the downhole tubular and inside the downhole tubular at the flow stop valve; and fluid above and below the flow stop valve inside the downhole tubular, wherein the flow stop valve comprises a first valve element (226?, 326?, 424) arranged such that the pressure difference acts across at least a portion of the first valve element and that the first valve element is movable between open and closed positions under action of said pressure difference so as to selectively permit flow through the downhole tubular, wherein the first valve element comprises a first passage (212, 312, 446) arranged so as to transmit fluid from a first port (213, 313, 447) in a first side of the first valve element to a second side of the first valve element, the first port being positioned such tha

Abstract: A modular pressure operated actuator can be coupled with a downhole tool to selectively operate it at least once. In the preferred embodiment the module can be mounted adjacent an isolation valve and after a fixed number of on and off pressure cycles allow a spring to push an actuator to operate the valve to an open position. The actuator, in another embodiment, can be reset with a tool run into the module to move the actuator back against a power spring and hold that spring force until the pressure cycling begins again. The preferred application is for a formation isolation ball valve but other valves, such as sliding sleeves, or other types of downhole tools can be actuated with the module that permits a retrofit of a hydraulic operation to a heretofore purely mechanically actuated tool.

Abstract: A system including a plurality of differential pressure actuated tools; a seat receptive to a plug; a first conduit fluidly communicating tubing pressure upstream of the seat to one end of each of the plurality of tools; and a second conduit fluidly communicating tubing pressure downstream of the seat to an opposite end of each of the plurality of tools and method.

Abstract: A method of actuating multiple valves in a well can include applying a pressure cycle to the valves without causing actuation of any of the valves, and then simultaneously reducing pressure applied to the valves, thereby actuating the valves. Another method can include releasing a locking device of each valve which prevents actuation, and then reducing pressure applied to the valves, thereby actuating the valves. A valve can include a port which provides for fluid communication between an exterior and an interior of the valve, a closure member which selectively permits and prevents fluid flow through the port, the closure member permits flow through the port in response to a decrease in a pressure differential from the interior to the exterior of the valve, and a locking device which prevents displacement of the closure member, the locking device being released in response to mechanical force applied to the locking device.

Abstract: An actuator assembly for effective interventionless activation of a valve in wells of multilateral architecture. The assembly may be pressure actuated from an oilfield surface even in certain circumstances where another valve in another leg of the well has been opened in a manner compromising pressure control of the well. Due to the multi-stage nature of the actuator, pressure based activation remains viable as a result of supplemental and/or fail-safe modes of actuation, for example, where such pressure control becomes compromised.

Abstract: An apparatus for controlling flow of a fluid includes a closure member, a biasing member applying a biasing force to the closure member, and a sealing member receiving the closure member. A dampener is operatively connected to the closure member and may resist a force applied to the closure member. A fluid seal may be formed when the biasing member presses the closure member against the sealing member. The apparatus may include a wellbore tubular in which the fluid conduit is formed and the closure member and sealing member may cooperate to control fluid flow along the fluid conduit. The apparatus may include an actuator configured to control the force applied to the closure member. The actuator may adjust the biasing force, and/or the dampening force. Also, a controller may control the actuator and may be responsive to a signal generated at a surface location, a signal generated at a downhole location, and/or a signal generated by a sensor.

Abstract: A regulation mechanism configured to automatically close off fluid flow through a line based on flow rate exceeding a predetermined level. This mechanism may be particularly beneficial when employed in conjunction with downhole chemical injection systems that are directed at well locations prone to becoming low pressure in nature. That is, in a conventional system, once the inherent pressure at the downhole end of an injection line exceeds that of the adjacent downhole environment, the flow rate of the column of fluid in the line may naturally increase as chemical is unintentionally emptied into the well. However, use of embodiments of the flow-based regulation mechanism detailed herein may near-automatically prevent such undesirable emptying of chemical into a low pressure well.

Abstract: An actuator or valve for use in a well comprising: an obstructing member, such as a piston, moveable between: a first position and a second position; and a retaining member, such as a ball, moveable between: a retaining position which retains the obstructing member in the first position; and, a release position which does not retain the obstructing member in the first position and/or allows or causes the obstructing member to move to the second position; wherein the retaining member is adapted to move in use, from one of the retaining position and release position to the other of the retaining position and release position, at least in part, by centrifugal forces caused by rotation of the actuator/valve. Thus at least some control of the actuation of the actuator/valve may be afforded by rotation thereof. In preferred embodiments some control is also afforded by fluid flow contacting the actuator/valve.

Abstract: A method of actuating multiple valves in a well can include applying one or more pressure cycles to the valves without causing actuation of any of the valves, and then reducing pressure applied to the valves, thereby resetting a pressure cycle-responsive actuator of each valve. A pressure cycle-operated valve for use in a well can include a closure member, a piston which displaces in response to pressure applied to the valve, and a ratchet mechanism which controls relative displacement between the piston and the closure member. The ratchet mechanism may permit relative displacement while one or more pressure cycles are applied to the valve, and the ratchet mechanism may prevent relative displacement in response to a pressure sequence of: a) a reduction in pressure applied to the valve, b) a predetermined number of pressure cycles applied to the valve, and c) an increase in pressure applied to the valve.

Abstract: A safety valve for an effluent-production installation, the safety valve comprising a longitudinal shell in which there extends a production tube defining an inside volume for effluent flow, the tube being movable in translation inside the shell in an axial direction between an advanced position in which effluent flow is authorized from the bottom of the installation towards the surface, and a retracted position in which effluent flow is prevented, the valve being characterized in that it further includes a connection duct between a feed line for feeding at least one additive from the surface and an injection line for injecting the additive downhole, a safety plug being provided in the connection duct in order to close or open the duct depending on whether the production tube is in its retracted position or its advanced position.

Abstract: A tool for selectively treating a wellbore with fluid that includes a tubing string having a sidewall defining an inner bore, the sidewall comprising a flow area having at least one fluid flow port that permits fluid flow through the sidewall. Fluid is prevented from flowing through the flow area when a closure is in a closed position. When in the open position, fluid flows through the flow area. An axial seal is connected to the closure to selectively close the inner bore against fluid pressure to apply the predetermined opening force to move the closure to the open position. A releasable connector connects the axial seal to the closure and a retrieval tool attachment releases the axial seal from the closure upon application of a predetermined release force by a retrieval tool.

Abstract: A remote actuation tool equipped with an intermediate volumetric mechanism for enhanced tool durability in high pressure differential downhole environments. Valve segments of the tool are actuated by power available due to a pressure differential between atmospheric and hydrostatic chambers of the tool. Yet, the intermediate volumetric mechanism, whether in the form of a discrete chamber or a hydraulic line system, minimizes stresses of the differential pressure on tool hydraulics. Thus, failure rates are substantially reduced. So, for example, the tool may be reliably employed in downhole environments which present differential pressures in excess of about 30,000 PSI.

Abstract: A system isolates a control system for a downhole tool from the internal pressures in the tubing in which the tool is mounted. Opposed seals are used on a moving component in the tool so as to offset pressure induced forces regardless of the internal operating pressure of the tool. In a particular application to a subsurface safety valve the control system can be isolated from tubing pressure by offset seals between the passage and the flow tube or around exposed portions of the operating piston for the flow tube.

Abstract: A downhole circulating tool including a sleeve with a cam slot having continuous and symmetrical wishbone patterns through which a cam pin moves. The cam pin moves simultaneously through symmetrical portions of the cam slot to alternate the opening and closing of first and second fluid port openings. A first port opening is operable to communicate fluid to a drill bit when open. A second port opening is operable to communicate fluid directly into the borehole or casing wall of a wellbore when open.

Abstract: An apparatus includes a string that extends into a well and a tool that is disposed in the string. The tool is adapted to form a seat to catch an object communicated to the tool via a passageway of the string in response to the tool being perforated.

Abstract: A drill pipe having a tubular body through which is provided a main bore, a side port provided in an exterior surface of the body, a side bore extending through the body from the main bore to the side port, and a valve member which is movable between a closed position in which fluid flow through the side bore is substantially prevented and an open position in which fluid flow through the side bore is permitted, wherein the movement of the valve member between the closed position and the open position comprises translational movement, and the valve member is located at least predominantly within the side bore.

Abstract: A pressure-actuated valve fit to a tubing string for alternately closing to communicate fluids from a wellbore to the tubing string and opening to communicate fluids from a wellbore annulus to the tubing string. The valve is particularly useful for lifting liquids which accumulate in the tubing string when the reservoir has a diminished pressure. In this case, gas is accumulated in the wellbore annulus and when the valve is opened the gas enters the valve and is directed to the tubing string for lifting the liquids. The valve is closed by a spring and has a closing-assist which applies an additional force to the spring to ensure the valve is fully closed.

Abstract: A downhole valve assembly including a valve mounted in a tubular body, the valve moveable between an open and closed position. Movement is achieved by a fluid operated valve actuation mechanism located downhole of the valve having a fluid inlet port located uphole of the valve. A method of controlling fluid flow downhole is also described allowing the valve to be moved between the open and closed positions and between closed and open positions.

Abstract: A pressure pulse signal is processed and a valve is operated to allow tubing or annulus pressure to move a piston against an atmospheric or low pressure chamber. Movement of the piston triggers the release of the dogs that previously held two components together for a separation. Redundant release mechanisms that respond to discrete pressure pulse signals are provided for backup purposes.

Abstract: A running tool has a stem for connecting to a string of conduit, a body, and a plurality of functional positions selected in response to rotation of the stem relative to the body. A feedback mechanism assembly is connected to the running tool and is operational with rotation of the stem relative to the body. The feedback mechanism assembly increases the torque required to rotate the stem relative to the body when the running tool has reached one of the plurality of its functional positions. The increased torque thereby provides a positive indication that the running tool has reached and is in the desired and proper functional position.

Abstract: A multi-barrier system includes a first valve in fluid communication with a lower completion, and a second valve in fluid communication with the lower completion. The first valve and the second valve are positioned proximate an uphole extent of the lower completion, and a packer located proximate the first valve and the second valve is closable in response to retrieving an upper completion.

Abstract: A hydraulic control system (100) for actuating a downhole tool. The hydraulic control system (100) includes a plurality of valve members (124) operable to selectively allow and prevent fluid communication between high and low pressure sources (54, 56) and first and second sides (58, 60) of an actuator (64) operably associated with the downhole tool. In the hydraulic control system (100), a first valve member (124) is ported between the high pressure source (54) and the first side (58) of the actuator (64), a second valve member (124) is ported between the low pressure source (56) and the first side (58) of the actuator (64), a third valve member (124) is ported between the high pressure source (54) and the second side (60) of the actuator (64) and a fourth valve member (124) is ported between the low pressure source (56) and the second side of the actuator (60).

Abstract: A bi-stable valve includes a first chamber having a first aperture and a second aperture, and a second chamber having a first aperture and a second aperture. The bi-stable valve also includes a shaft having a first valve member adjacent a first end of the shaft and a second valve member adjacent an opposite second end of the shaft. The shaft is movable between a first position, in which the first valve member closes off the second aperture of the first chamber and the second valve member closes off the second aperture of the second chamber to prevent fluid from passing through the second apertures of the first and second chambers, and a second position, in which the first valve member and the second valve member allow fluid to pass through the second aperture of the first chamber and the second aperture of the second chamber.

Abstract: A flow restrictor for controlling the flow of cement or other fluid in oil wells comprises a plurality of restrictor elements, each defining first and second apertures, which are assembled in a stacked configuration and slidingly inserted into the well casing or other tubing so that the first apertures define a direct flowpath, preferably including a non-return valve, and the second apertures define a second, indirect flowpath between the elements and the inner surface of the tubing. The elements include seals for fluidly sealing each element in the bore of the tubing which are preferably slidably retractable and resiliently radially outwardly biased so as to adapt conformably to different tubing types having different internal diameters. The restrictor may slide along the tubing in use.

Abstract: A work string tool to be operably associated with a weight-set packer tool uses pressure applied by fluid circulated from the surface above the weight-set packer, to deploy a hydraulic hold-down anchor mechanism above the packer to reduce the risk of unsetting during a high pressure “positive” wellbore integrity test. An axial bore of a tool tubular body houses first and second inner sleeves, and is configured to accommodate independent axial movement of the sleeves to provide multiple fluid flowpath configurations through the tool which allow use of circulation fluid to pressure to circulate a ball obturator to a valve seat in a sleeve when a configuration change is required to deploy or release the anchor means.

Abstract: The present invention regards a device designed for injection of fluids in a well bore, typically an offshore well bore for petroleum production and gas injection/gas lift system for fluid injection. The device comprises a outer hollow housing (1) with an internal body (2) moveable within the outer housing (1) with an internal bore (3) which in a first closed position is closed with a metal to metal seal system between the outer housing (1) and the internal body (2), which internal body (2) is operated by pressure differential across the internal body (2), where the internal body (2) is designed with slots (4) forming outlets of the internal bore (3) which in an open position of the device is positioned outside of the outer housing (1).

Abstract: A safety valve for use in a subterranean well can include a housing assembly having a flow passage extending longitudinally through the housing assembly. An outer diameter of the housing assembly is eccentric relative to the flow passage. A well tool can include a magnetic coupling between magnet devices. One magnet device includes a series of magnets which are unequally spaced circumferentially about the other magnet device. Another safety valve can include a longitudinally extending flow passage, a closure device which selectively permits and prevents flow through the flow passage, and an outer diameter which is eccentric relative to the flow passage.

Abstract: The present invention regards a device designed for injection of fluids in a well bore, typically an offshore well bore for petroleum production and gas injection/gas lift system for fluid injection. The device comprises a outer hollow housing (1) with an internal body (2) moveable within the outer housing (1) with an internal bore (3) which in a first closed position is closed with a metal to metal seal system between the outer housing (1) and the internal body (2), which internal body (2) is operated by pressure differential across the internal body (2), where the internal body (2) is designed with slots (4) forming outlets of the internal bore (3) which in an open position of the device leads to the outside of the outer housing (1).

Abstract: A wellbore tubular port closure system includes a mechanism to delay the opening of the port after the port closure has been actuated to open. A method and apparatus incorporate the wellbore tubular port closure system with a port opening delay mechanism configured to act after actuation of the pressure responsive mechanism to delay full movement of the port-closure to the port-open position until after a selected time has lapsed.

Abstract: A downhole assembly includes an apparatus for generating a fluid pressure pulse downhole. A disclosed apparatus for generating a fluid pressure pulse downhole includes an elongate, generally tubular housing defining an internal fluid flow passage and having a housing wall. The apparatus also includes a device for selectively generating a fluid pressure pulse, the device having a cartridge which can be releasably mounted entirely within a space provided in the wall of the tubular housing. The internal fluid flow passage defined by the tubular housing is a primary fluid flow passage. A secondary fluid flow passage has an inlet which communicates with the primary fluid flow passage. The cartridge houses a valve actuable to control fluid flow through the secondary fluid flow passage to selectively generate a fluid pressure pulse. Data relating to a measured downhole parameter or parameters can be transmitted to surface via the pressure pulses.

Abstract: A gas-lift valve comprising an elongated vertically orientated tubular body with inlet ports positioned for communication with the inlet ports of a gas-lift valve mandrel, a valve seat and valve port at the upper end of the valve body, a movable gas charged dome positioned within the body below the valve seat, a valve ball assembly attached to the dome, and a collapsible bellows positioned to move the dome and manipulate the valve ball assembly downward onto and off of the valve seat in response to pressure from said inlet ports of the valve body and pressure on the seat and thereby allow injection gas to flow upward through the valve port to exit at the upper end of the valve body. A tubular latch is provided with a removable plug to provide for pressure testing and completion of the well with only one wireline trip.

Abstract: An apparatus and process for gas, oil, and other fluid production using bailer technology with stimulation to enhance production. An enclosed apparatus and process for removing gas, oil, and/or other fluids from a well while reducing environmental impact. A novel divalve for simultaneously closing a conainer and dumping liquids into it.

Abstract: A chemical injection system for controlling injection of an injection fluid from an injection fluid supply at a surface location into a production tubing assembly having an upper flow path, a first flow zone, and a second flow zone. The chemical injection system comprises a first fluid injection line configured to inject the injection fluid into the first flow zone and a second fluid injection line configured to inject the injection fluid into the second flow zone. A main fluid supply line is configured to fluidly connect both the first fluid injection line and the second fluid injection line to the injection fluid supply.

Abstract: A fill-up and circulation tool includes a mandrel; a packer assembly is disposed around the mandrel; and a valve assembly connected to the mandrel, wherein the valve assembly is configured to selectively control fluid flow into the tool and out of the tool.

Abstract: An apparatus and method is disclosed for remotely operating a downhole tool within a wellbore. The wellbore extends from a ground or subsea surface downward into the earth. The apparatus includes a tool having a production assembly with at least one sleeve adapted for movement from a first sleeve position facilitating entry of formation fluids past the sleeve into the wellbore to a second sleeve position that retards entry of formation fluids. The downhole tool may be configured to resume production following fracturing, gravel packing or other operations without the need for additional trips into the well for the purpose of opening production sleeves. A fluid pressure pulse or electromagnetic signal or other signal may be delivered downhole for remote mechanical actuation of the apparatus.

Abstract: An apparatus and device for hydrocarbon recovery in a well for coal bed methane (CBM) recovery, tight sand gas extraction, and other gas extraction techniques provides for the formation of a hydrocarbon foam comprised of a fluid delivered into a downhole portion of the well and the hydrocarbon, maximizing water removal for gas recovery. The apparatus may include a check valve that feeds a nozzle to deliver or atomize the spray of fluid into the downhole portion of the well when the pressure applied to the fluid is sufficient to overcome a hydrostatic pressure in the downhole portion of the well and to deliver the fluid into the downhole portion of the well. The fluid is not sprayed directly into the formation, thereby protecting the formation from damage and recovering the fluid even in the case where water is not present. The capillary tube feeding the fluid to the check valve may be placed externally to the production tube to facilitate ease of cleaning and clearing of the production tube.

Abstract: A downhole isolation valve for testing the integrity of a tubular within a wellbore includes a tubular body (12) with an axial through bore (14) having a reduced diameter portion (29) defining a valve seat (16) and a ledge (17); an inner sleeve (18), with a closed end (22) configured to seal within the valve seat, a shoulder (28) spaced from that closed end, and a radial outlet (24) positioned between the shoulder and the closed end; wherein in use the inner sleeve is selectively moveable within the bore at a predetermined pressure between a closed position, in which there is no flowpath through the bore, and an open position, in which the closed end is positioned beyond the valve seat to expose the radial outlet to the through bore beyond the valve seat and provide a flowpath through the bore of the outer tubular body.

Abstract: In one aspect, an apparatus for use downhole is disclosed that in one configuration includes a downhole device configured to be in an active position and an inactive position and an actuation device that includes: a housing including an annular chamber configured to house a first fluid therein, a piston in the annular chamber configured to divide the annular chamber into a first section and a second section, the piston being coupled to a biasing member, a control unit configured to enable movement of the first fluid from the first section to the second section to supply a second fluid under pressure to the tool to move the tool into the active position and from the second section to the first section to stop the supply of the second fluid to the tool to cause the tool to move into the inactive position.

Abstract: A safety valve system includes a safety valve having an actuator and a line connected to the actuator. The safety valve is operable by opening the line in the well, with the line being free of any connection to a surface control system. Another safety valve system includes multiple safety valves. An actuator of each safety valve is connected to an actuator of another safety valve via a line. A biasing force in each of the actuators is operative to close the respective one of the safety valves in response to opening of the line. The biasing force is produced at least in part by hydrostatic pressure in a well.

Abstract: Back pressure control devices used to control fluid pressure in a wellbore require various utilities for operation, such as an air supply. Apparatus disclosed herein provide for the continued operation of one or more back pressure control devices when supply of utilities for operation of the back pressure control devices are intentionally or unintentionally interrupted.

Abstract: A differential pressure operated blanking tool includes a Y-tool having first and second limbs connected together via a throat. A ball valve is selectively positionable to close one or other limb of the Y-tube against fluid flow. A housing has an opening in one side thereof of a size sufficient to allow the hall to pass through, and an actuator mounted on the second limb and in the housing wherein fluid flow within the tool carries the ball valve through the opening in the housing to a position where the second limb is closed against bias of the actuator. When the fluid flow is removed, the actuator operates to force the ball valve out of engagement with the second limb whereupon the ball passes through the opening in the housing towards the first limb.

Abstract: A method of actuating a well tool utilizing first and second pressure sources includes the steps of: placing an actuator chamber in communication with the first pressure source, thereby displacing a piston from a first position to a second position; and then placing another chamber in communication with the second pressure source, thereby displacing the piston to a third position. A multi-position actuator includes an operating member which displaces to operate a well tool, a first position of the operating member corresponding to a pressure source being in communication with a chamber and another pressure source being in communication with another chamber, a second position of the operating member corresponding to the same pressure source being in communication with both of the chambers, and a third position of the operating member corresponding to the pressure sources being connected to the chambers oppositely to that of the first position.

Abstract: A downhole valve comprises a tubular body and a valve member. The valve member is normally closed and in the closed position may prevent or restrict passage of a working fluid through the body. The valve member is movable to an open position, a first working fluid pressure differential being necessary to move the valve member from the closed position and a lower second working fluid pressure differential being necessary to maintain the valve member in the open position.

Abstract: Drill string flow control valves and more particularly, drill string flow control valves for prevention of u-tubing of fluid flow in drill strings are provided. Drill string flow control valves may comprise a valve housing, a valve sleeve axially movable within a valve housing from a closed position to an open position, a piston axially movable within said valve housing and bearing against the valve sleeve, a biasing mechanism for biasing the valve sleeve into the closed position, a static pressure port for actuating said piston utilizing internal fluid pressure within said valve and a plurality of dynamic pressure ports for allowing a differential pressure to be exerted on the valve sleeve during dynamic flow conditions. The differential pressure exerted on the valve sleeve may be the result of an upstream pressure and a downstream pressure during fluid flow through said valve.

Abstract: A downhole tool assembly is configured for repeated and selective hydraulic actuation and deactuation. A piston assembly is configured to reciprocate axially in a downhole tool body. The piston assembly reciprocates between a first axial position and second and third axial positions that axially oppose the first position. The downhole tool is actuated when the piston assembly is in the third axial position and deactuated when the piston assembly is in either of the first or second axial positions. A spring member biases the piston assembly towards the first axial position while drilling fluid pressure in the tool body urges the piston assembly towards the second and third axial positions. Downhole tool actuation and deactuation may be controlled from the surface, for example, via cycling the drilling fluid flow rate.

Abstract: A system for pressure testing the joints and walls of a production pipe includes a fluid system component that can be disposed at a first end of the production pipe so as to seal off the first end of the production pipe. The fluid system component prevents the flow of fluid out of the first end of the production pipe when the pressure within the production pipe is below a predetermined level. The fluid system component includes a sacrificial element that is adapted for preferential failure when the pressure within the production pipe exceeds the predetermined level. Upon failure of the sacrificial element, fluid is able to flow out of the production pipe through the fluid system component. The system may also include a test plug that prevents the activation of a drain component in the production pipe during the pressure testing of the production pipe.

Abstract: A method of actuating a valve in a well can include storing energy as a result of a differential pressure across a closed closure device of the valve, and releasing at least a portion of the stored energy while opening the closure device. A valve for use in a well can include a closure device, a biasing device, and an actuator which stores energy in the biasing device in response to a pressure differential across the closure device. A well system can include a tubular string, and a valve which controls fluid flow through the tubular string. The valve may include a closure device and an actuator which actuates the valve at least partially in response to a pressure differential across the closure device.

Abstract: A mud saver valve, positionable at the bottom of the drill string, above the bit, which includes an elongated body portion; portion of the valve housing a compressible spring a pressure; a valve mechanism which is a sliding sleeve moveable between open and closed positions within the valve; while in the closed position, drilling fluid cannot pass through the valve; when a combination of static and pump pressure exceeds the setting pressure of the dome, the sleeve will be moved by actuation pistons to the open position, at which drilling fluid is allowed to through the valve. Also, wherein when the valve is normally closed, as long as the fluid column pressure is less than the setting pressure, the valve remains closed, and allows the drill string to be disconnected and a section of pipe can added without the fluid draining from the drill column above the bit, and thus saving fluid.

Abstract: A method of controlling operation of multiple valves interconnected in a tubular string in a subterranean well can include opening each of the valves, and then closing the valves in response to an application of pressure to the tubular string. A well system can include multiple valves interconnected in a tubular string, each of the valves including an actuator, and a valve control device interconnected in the tubular string. The valve control device may be connected to each of the valve actuators via multiple flow paths, whereby a pressure differential generated between the flow paths is also generated in each of the valve actuators.