Abstract: A downhole tool (34) comprising a housing (60), a mandrel (76) slidably disposed within the housing (60), the mandrel (76) having a fluid passageway (52) extending axially therethrough, a valve (50) disposed within the mandrel (76), the valve (50) having first and second positions to selectively permit and prevent fluid flow through the fluid passageway (52) of the mandrel (76) and first and second pistons (98, 104) slidably disposed between the housing (60) and the mandrel (76), the first and second pistons (98, 104) slidably displacable in opposite directions relative to the housing (60) in response to a differential fluid pressure, the first and second pistons (98, 104) selectively engagable with the mandrel (76) to respectively displace the mandrel (76) in first and second directions, thereby operating the valve (50) between said first and second positions.

Abstract: A downhole tool comprises a tubular body (12) for location in a tubular member, such as a drill string, and defines a through bore (20) and a number of circumferentially spaced ports (26). A valve member which may be in the form of a piston sleeve (24) is mounted in the bore (20) and is movable relative to the body (12) between a first position in which fluid may flow through the port (26) and a second position in which the valve member (24) closes the port (26), the valve member being movable between the first and second positions by application of differential fluid pressure. Movement of the valve member (24) is provided by a cam arrangement including a circumferentially extending cam groove (56) and a cam follower (57).

Abstract: A subsurface safety valve includes a one piece pressure housing having a flow passage provided therethrough and a recess formed in a side wall of the flow passage. A flapper member having first and second, respectively open and closed positions, is mounted to the housing in the recess. A control mechanism controls movement of the flapper member between its first and second positions. The control mechanism may include at least one piston substantially longitudinally aligned with flow passage wall, the at least one piston being positioned in longitudinal relation to a portion of a surface of the wall, the surface of the wall being provided with a longitudinal groove and the at least one piston being provided with a protrusion which is received within the longitudinal groove.

Abstract: Apparatus and method of isolating a well to allow intervention equipment to be installed in the upper section of tubing and surface equipment to be tested prior to running in the well is described which enables a surface test tree to be leak-off tested on a regular basis and enables the SSTT valves to be pressure tested before opening and after relatch. This is achieved by providing a completion lubricator valve comprising a fail open valve (18) located above a conventional downhole safety valve (20), the fail open valve (18) being closable by the application of hydraulic closure pressure (42) to allow a pressure differential to be supported from above. The valves (18, 20) are flapper valves and are spring-biased to open or closed positions as necessary. This allows the intervention equipment to be installed in the upper section of the tubing and the surface equipment to be tested prior to running in the well and enables the injection head to be installed immediately upon the production tree.

Abstract: A new valve has been invented, in some aspects useful in wellbore operations and/or as a mud saver valve which valve has a body through which fluid is flowable, a valve seat connected in and to the body and through which fluid is flowable, a valve member positioned adjacent the valve seat and selectively movable to seat against the valve to close the valve to fluid flow and selectively movable away from the seat to open the valve to fluid flow, and at least one recess on the valve member for holding debris and thereby preventing the debris from inhibiting valve closure.

Abstract: An annular safety valve system provides a retrievable annular safety valve and packer. In a preferred embodiment, an annular safety valve system has an annular safety valve connected to an upper tubing string extending to the earth's surface. The annular safety valve is initially connected to the hydraulically set packer which has no openings through an inner mandrel thereof. The safety valve is retrievable separate from the packer after the packer has been set. The safety valve is rotated relative to the packer in order to release the safety valve from the packer. As the safety valve is rotated, a setting line of the packer is severed. Other transmission lines, electrical wires, etc. may be severed as well. The safety valve may then be raised to the earth's surface with the tubing above it. A replacement safety valve is also provided for installing in the packer after the prior safety valve is retrieved.

Abstract: The present invention is directed to an annulus access valve system for selectively opening and sealing an annulus bore in a wellhead apparatus comprising an annular bore insert sealingly and fixedly attached within the annulus bore; at least one flow port formed in the bore insert for establishing a fluid path through the annulus bore; an annular valve sleeve sealingly and slideably attached within the bore insert; and a hydraulic actuator for raising and lowering the valve sleeve over the flow port; whereby the sleeve may be actuated to open the flow port and thereby open the annulus bore and the sleeve may be actuated to close the flow port and thereby seal the annulus bore.

Abstract: A fill valve includes a tubular housing which accommodates a valve member which is biased toward a closed position by a light spring. The valve member includes a head and a tubular portion which is provided with two large windows. When the fill valve is open fluid flows freely through the tubular portion of the fill valve and out of the windows.

Abstract: A fill valve includes a tubular housing which accommodates a valve member which is biased toward a closed position by a light spring. The valve member includes a head and a tubular portion which is provided with two large windows. When the fill valve is open fluid flows freely through the tubular portion of the fill valve and out of the windows.

Abstract: A time delay mechanism wherein there is provided a time delay between the application of a pressure to the mechanism and an action being carried out as a result of the application of said pressure. The mechanism may comprise a first piston and piston chamber and a second piston and piston chamber. Communication of a viscous fluid between said piston chambers may be achieved by means of at least one contoured flow passage.

Abstract: A bore-hole pump for pumping a highly viscous fluid, into which is fed a solvent which has a low viscosity and which is miscible with the fluid. A shutoff device is disposed between an inlet of the bore-hole pump and an actual inlet of the pump part. The shut-off device is activated by the solvent.

Abstract: The invention relates to a control system for a subsurface safety valve (SSV). A pressure-balance feature is introduced such that the control system components are unaffected by the depth of placement of the SSV. Through the use of this feature, the standard hydraulic control system used for surface components can also be used for an SSV regardless of its depth of installation. In another feature of the invention, a shuttle valve is provided so that each time the SSV is stroked, a volume of control fluid is purged into the annulus. One embodiment of the shuttle valve may or may not be sensitive to annulus pressure and employs annulus pressure as an aid to stroking the shuttle valve upon application of surface control pressure to assist in actuation of the SSV, while at the same time providing for a purge of a controlled volume of fluid.

Abstract: A subsurface safety valve of minimized length comprises a tubular valve housing with a valve closure member therein movable between an open and a closed position, an axially shiftable flow tube for opening the valve closure member, a plurality of longitudinally disposed springs radially spaced about the housing for biasing the flow tube to a closed position, and a piston and cylinder assembly to move the flow tube to an open position, with a portion of the assembly longitudinally overlapping at least one of the springs. The safety valve includes simple mechanisms to lock out the safety valve, and to establish secondary hydraulic communication with a wireline set secondary valve set within the locked out safety valve.

Abstract: An improved mechanical system selectively locks the tester valve of an annulus pressure responsive tester valve in position for an indeterminate number of well annulus pressure cycles. The tester valve can be closed upon demand. The forces which accomplish opening of the ball valve act across a power piston, but the forces which close the valve act across an actuating piston. The tester valve can be run into a well with an operating element of the tester valve in a first position, such as a closed position. Upon reaching the desired depth within the well and setting of an associated packer system, well annulus pressure is then increased to a first level above hydrostatic pressure to move the power piston and thus move the tester valve to an open position. During a normal mode of operation, well annulus pressure can be cycled between hydrostatic pressure and the first level to open and close the tester valve.

Abstract: A fill valve includes a tubular housing which accommodates a valve member which is biased toward a closed position by a light spring. The valve member includes a head and a tubular portion which is provided with two large windows. When the fill valve is open fluid flows freely through the tubular portion of the fill valve and out of the windows.

Abstract: A mud saver valve has been developed for controlling flow of drilling fluid through an upper portion of a drill string, the mud saver valve in one aspect has a tubular housing, a ball closure rotatably disposed within the tubular housing, the ball closure having a body, a flow channel therethrough, a first body side and a second body side opposite the first body side, a first lug projecting from the first body side and a second lug projecting from the second body side, a sleeve assembly movably disposed within the tubular housing, the sleeve assembly having a first and a second actuator e.g, dogs, to engage corresponding first and second lugs of the ball closure to open or close the ball closure in response to fluid pressure conditions as well as engagement and disengagement of the tubular housing with the drill pipe against the force of a coil spring disposed within the tubular housing.

Abstract: The present invention provides a single trip system for placing perforating apparatus and sand control equipment in a wellbore. This system includes a casing string equipped with extendible pistons and a pumpable activator plug for extending the pistons. Additionally, this system utilizes a single gravel-pack and completion tool string. Further, this system includes a means for opening the extendible pistons to fluid flow.

Abstract: A subsea well assembly has guides for orienting electrical connectors located on a concentric tubing hanger and on the tree. The guides use a guide slot and key to rotate the electrical connectors on the lower end of the tree when the tree is installed on the wellhead. The tree electrical connectors are located on the upper guide member and rotate relative to the tree as the guide slot engages the guide key. An annulus valve in the tubing hanger uses a sleeve with inner and outer metal seal lips.

Abstract: Internal and external metal-to-metal radially interfering seals are provided for an annular chamber. Typically, an annular chamber is used in tubular goods to be part of the hydraulic control circuitry, such as for operating subsurface equipment such as a subsurface safety valve. Resilient seals are eliminated and sealing reliability is enhanced by a design which features metal-to-metal seals internally and externally, preferably assembled by an external two-step thread. The radial interference seal, which is internally disposed, is constructed so as to be incapable of experiencing tensile loads. This reinforces joint integrity by minimizing stresses on thin components.

Abstract: An annulus pressure responsive tool of the type which contains lateral circulation ports and a ball valve, each operable between open and closed positions to configure the tool into different modes of operation. These modes include a well test position in which the ball valve is open and the circulation ports are closed, a blank position in which the ball valve and circulation ports are both closed, and a circulating position in which the ball valve is closed and the circulating ports are open. Through manipulation of annulus pressure, the tool mode can be changed during the annulus pressure release to move out of the well test position and into the blank and circulating positions. An operating mandrel assembly is slidably disposed within the exterior housing of the tool and its movement dictates the positions of both the circulation ports and the ball valve.

Abstract: A fill valve includes a tubular housing which accommodates a valve member which is biased toward a closed position by a light spring. The valve member includes a head and a tubular portion which is provided with two large windows. When the fill valve is open fluid flows freely through the tubular portion of the fill valve and out of the windows.

Abstract: The present invention provides a method and apparatus for controlling the flow of fluids being injected into an oil or gas well through a tubing string, including a generally cylindrical hollow body for connection to the tubing string for receiving and selectively conveying fluids received from the tubing string therethrough, the body having an open top end and an open bottom end, the body having a flow passage therein for conveying fluids from the top end of the hollow body to the bottom end of the hollow body, the top end being provided with a device for connecting the top end to the tubing string, the bottom end being provided with a device for connecting the bottom end to a tool for injecting the fluids into a well, a movable piston slidably received in the body, the movable piston being movable upward against a top seal to stop the flow of fluids through the flow passage and being movable downward against a stop to enable fluids to flow through the flow passage from the top end to the bottom end in respo

Abstract: A coiled tubing completion system is provided with a plurality of completion apparatus, all of which is designed flush with the diameter of the coiled tubing outside diameter for avoiding upsets and are flexible, spoolable on a coiled tubing reel and having through bores large enough to pass wireline tools for performing other operations. The spoolable coiled tubing system may use standard coiled tubing well control equipment and can be used in live wells. The flush, flexible, spoolable and through bore completion equipment may include a tubing retrievable safety valve, an annular control valve, concentric gas lift valves, a zone packer, a landing nipple, a sliding sleeve, and may include at the end a non-flexible but flush and open bore production packer and pump out plug. The completion system may be retrieved through a retrieval system.

Abstract: There is disclosed a surface controlled, subsurface tubing safety valve having a tubular body with a bore therethrough disposable in a tubing string, and a flapper which is movable within-the body between open and closed positions and yieldably urged toward its closed position. The flapper is adapted to be opened by a flow tube which is vertically reciprocable within the body between upper and lower positions. The flow tube is yieldably urged to its upper position to permit the flapper to close, and is lowered to open the flapper by a flexible bellows which has a well pressure on one side and a pressure chamber on one side containing hydraulic fluid which is displaced to cause the bellows to move between expanded and contracted positions in response to the exhaust or supply of control fluid from a source at the surface, the bellows being connected to the flow tube to lower it as the bellows is moved to one position and to permit it to rise as the bellows moves to the other position.

Abstract: There is disclosed a subsurface tubing safety valve having a normally closed flapper which is adapted to be moved to open position by a flow tube reciprocable within the body of the valve. The flow tube is urged to flapper opening position by hydraulic fluid from a remote source and is urged to a position permitting the flapper to close by a curved beam type spring.

Abstract: A differential pressure operated valve for use as a circulating and/or deflation valve in a well bore. The valve comprises a housing defining first and second bores therethrough and a passage providing communication between the interior and exterior of the housing. A valve sleeve is slidably disposed in the housing and has a first outer surface slidably disposed in the first bore and a second outer surface slidably disposed in the second bore. A valve port is defined in the valve sleeve providing communication between a central opening thereof and the passage in the housing when the valve sleeve is in an open position. When the valve sleeve is closed, the valve port and passage are isolated from one another. The first and second outer surfaces of the valve sleeve define a differential area, and the valve is closed by fluid flow creating a differential pressure acting across this area. A spring biases the valve toward the open position.

Abstract: A tandem safety valve for use in a tubing string in a wellbore has a pair of identical valves disposed in a valve housing. Each valve has a flow tube for selectively opening and closing each valve. Each valve is provided with an hydraulic normal-operation actuator and an hydraulic looking actuator. The normal-operation actuator and locking actuator are selectively engaged with the flow tube disposed within the valve housing. Each flow tube is provided with a latch to releasably engage the normal-operation actuator, and a a locking dog to selectively engage the flow tube in a locked-open position. The locking actuator engages the latch to release the normal-operation actuator from engagement with the latch and to permit the locking dog to engage the valve housing to maintain the flow tube and valve in a locked-open position.

Abstract: A well fluid sampling tool and method for retrieving single-phase hydrocarbon samples from deep wells. The sampling tool is lowered to the required depth, an internal sample chamber is opened to admit well fluid at a controlled rate, and the sample chamber is then automatically sealed. The well fluid sample is immediately subjected to a high pressure to keep the sample in its original single-phase form until it can be analyzed.The sample is pressurized by a hydraulically-driven floating piston powdered by high-pressure gas acting on another floating piston. Once sampling is initiated, e.g. by an internal clock, the entire sequence is automatic.Also disclosed is a sample transfer container for securing the pressurized sample from the tool and maintaining it in single-phase form during transport to an analytical laboratory.This invention avoids the disadvantages arising from phase separation of hydrocarbon well fluid samples.

Abstract: In the present invention a testing tool having an axial flow passage is arranged to be connected in a pipe string and placed in a well bore. Communication through the flow passage is controlled by a valve member which is cooperatively arranged in the body to be moved back and forth for selectively opening and closing communication through the flow passage. The testing tool further includes upper and lower mandrels that are selectively coupled together by a unique clutch mechanism that enables the valve member to be successively opened and closed as the well bore pressure is increased and decreased a predetermined number of times in a testing cycle. The clutch mechanism is thereafter operable for temporarily uncoupling the mandrels to enable the valve member to be retained in its open position as the well bore pressure is increased and decreased in a subsequent operating cycle of the test valve before resuming the testing operation.

Abstract: A fluid flow control valve having an adjustable opening pressure and using expendable components therein for use in pumping highly abrasive fluids therethrough.

Abstract: A subsurface safety valve has a valve seat and an upwardly closing flapper plate whose sealing surfaces each have a matched spherical radius of curvature. The sealing surface of the valve seat is a concave spherical segment and the sealing surface of the flapper plate is a convex spherical segment. The matching spherical surfaces are lapped together to provide a metal-to-metal seal along the interface between the nested convex and concave sealing surfaces. This permits angular displacement of the flapper plate relative to the valve seat without interrupting positive sealing engagement. The concave spherical seating surface of the safety valve seat will tolerate a limited amount of misalignment of the flapper plate which sometimes occurs during operation of the safety valve under high flow rate, high differential pressure conditions.

Abstract: A system for controlling a plurality of downhole apparatus comprises a housing inside which a biasing force is provided. An activating force can be received in the housing so that the activating force acts in opposition to the biasing force. The plurality of downhole apparatus are selectively operated in response to different magnitudes of the activating force acting in opposition to the biasing force. The present invention also provides a corresponding method.

Abstract: A safety system including a surface controlled subsurface safety valves for use in a well having annulus fluid flow. One of the safety valves has a valve closure member, and a small diameter offset piston actuator to move the valve closure member in response to control fluid pressure conducted from the well surface to its open position which allows annulus fluid flow. A spring biases the valve closure member to block annulus fluid flow. The annulus safety valve has an enlarged flow area for use in high volume gas injection wells. The annulus safety valve has metal-to-metal sealing systems to improve valve life under harsh downhole well environments.

Abstract: A subsurface well safety valve having a flow tube telescopically movable in the housing for controlling movement of a valve closure member. A piston and cylinder assembly actuates the flow tube and it is in communication with hydraulic control fluid on one side and a gas biasing chamber on a second side and includes a biasing spring acting on the flow tube to close the valve. A second piston is telescopically positioned in the first piston with two different sized sealing areas, one of which is exposed to hydraulic fluid and the second of which is exposed to the gas chamber. In the event of loss of gas pressure, the second piston will separate from the first piston causing hydraulic pressure equalization and failsafe closure of the valve.

Abstract: A downhole, inline well safety shutoff valve has a spring-loaded, normally closed flapper shutoff valve element that may be opened by a downwardly driven movement of an operator tube coaxially and slidably disposed within the tubing string bore. The operator tube is vertically driven by a rod structure disposed in an offset passageway in the safety valve housing and operated by fluid control pressure transmitted thereto from the surface. To substantially preclude undesirable communication in the passageway between pressurized production fluid and pressurized rod control fluid, the rod structure is slidably carried within a specially designed seal structure including a cylindrical sleeve coaxially received in the offset passageway, and a sealing ring captively retained between the top end of the sleeve and an annular ledge formed in the passageway. The sealing ring functions to create a dynamic seal around the rod side surface and a static seal between the ring and the interior passageway surface.

Abstract: Improved methods and apparatus are provided for obtaining multiple fluid samples from subterranean formations of interest. The present invention is particularly well suited for testing nuclear migration in ground water utilizing test wells surrounding a nuclear test site. A plurality of flow ports are provided in the casing each at a depth of a formation of interest, and a sliding sleeve is positioned over each port. A wireline tool is lowered to the selective depth, and downhole electric motor energized to power a pump and pass pressurized fluid to move a first dog radially outward. The downhole tool may be axially moved until the first dog locks into a groove provided in the casing. Fluid entering the casing is sealed above and below the sliding sleeve. Fluid pressure may then be applied to move a second dog radially outward to engage the sliding sleeve, and a control valve regulated to apply fluid pressure to axially move the sleeve and open the port.

Abstract: A well completion system and method in which reeled tubing is connected in the completion string which includes a safety valve and a sliding sleeve valve. A straddle assembly is provided within the sliding sleeve valve for sealing against axial flow of fluid and isolating a lateral fluid flow path. A stinger assembly is provided which is insertable within the straddle assembly and connectable to the reeled tubing to lock the reeled tubing relative to the straddle assembly and the sleeve valve. The sliding sleeve valve functions to selectively control the lateral flow of production fluid into the production string for upward flow through the safety valve and the reeled tubing to the ground surface.

Abstract: A downhole, inline well safety shutoff valve has a spring-loaded, normally closed flapper shutoff valve element that may be opened by a downwardly driven movement of an operator tube coaxially and slidably disposed within the tubing string bore. The operator tube is vertically driven by a rod structure disposed in an offset passageway in the safety valve housing and operated by fluid control pressure transmitted thereto from the surface. To substantially preclude undesirable communication in the passageway between pressurized production fluid and pressurized rod control fluid, the rod structure is slidably carried within a specially designed seal structure including a cylindrical sleeve coaxially received in the offset passageway, and a sealing ring captively retained between the top end of the sleeve and an annular ledge formed in the passageway. The sealing ring functions to create a dynamic seal around the rod side surface and a static seal between the ring and the interior passageway surface.

Abstract: For use as part of a test string employed to evaluate the production potential of a chosen formation through which an oil well has been drilled, an annulus-pressure-operated sub-surface control valve, typically a ball valve, wherein to deal with the problem of the high pressure of fluid acting on the upstream side of the ball resulting in the frictional forces caused by the ball being pressed up against the seating on its downstream side making the ball stick, the utilization of a differential thread force multiplier by which the actuating force may be applied to the ball.

Abstract: An annulus pressure responsive downhole tool includes a housing with a power piston slidably disposed therein. First and second pressure conducting passages communicate a well annulus exterior of the housing with first and second sides of the power piston. A flow restrictor is disposed in the second pressure conducting passage so that a relatively rapid increase in well annulus pressure creates a pressure differential across the power piston to move the power piston. A volume of silicone oil is contained in a first portion of the second pressure conducting passage between the second side of the power piston and the flow restriction, for accommodating displacement of the power piston as it moves. An operating element is disposed in the housing and movable from an initial position to a final position. The operating element is associated with the power piston so that the power piston moves the operating element from its initial position to an intermediate position.

Abstract: The present invention relates to a subterranean well annulus pressure safety valve. In one embodiment, the valve is full opening to permit complete access therethrough of wireline and other remedial tools, and contains the annulus safety valve members completely offset from the central housing. The invention also relates to an annulus safety valve wherein a series of valve elements are placed exterior of a central housing and may be staged to open in series upon incremental increase of pressure thereacross. The annulus safety valve also provides pressure equalization means to equalize pressure across the valve cluster prior to opening of the cluster. The annulus safety valve also has selectively disengagable sealing plug means therein which may be removed while the valve is in the well to increase total fluid flow area through the valve components of the apparatus. A method of controlling an annular area interior of casing within a well using the annulus safety valve also is disclosed.

Abstract: A downhole, inline well safety shutoff valve has a spring-loaded, normally closed flapper shutoff valve element that may be opened by a downwardly driven movement of an operator tube coaxially and slidably disposed within the tubing string bore. The operator tube is vertically driven by a rod structure disposed in an offset passageway in the safety valve housing and operated by fluid control pressure transmitted thereto from the surface. To substantially preclude undesirable communication in the passageway between pressurized production fluid and pressurized rod control fluid, the rod structure is slidably carried within a specially designed seal structure including a cylindrical sleeve coaxially received in the offset passageway, and a sealing ring captively retained between the top end of the sleeve and an annular ledge formed in the passageway. The sealing ring functions to create a dynamic seal around the rod side surface and a static seal between the ring and the interior passageway surface.

Abstract: Apparatus for the venting and isolation of an oil well test tool drill string comprises reference pressure gas release apparatus having two spaced pistons (7, 11) located at opposite ends of the reference gas chamber (10) and blocking both a gas vent (17) to annulus and a hydraulic liquid passageway (22) extending further up the test string, the pistons being held together by a shear pin (13) until the application of a predetermined higher pressure across those pistons causes the pin to shear, allowing sequential movement of the two pistons toward each other, firstly opening the gas vent to annulus, and secondly opening the passageway (22) to a chamber (24) of hydraulic liquid. The hydraulic liquid pressure within this passageway then causes actuation of ball valve apparatus for isolating the upper section of tubing, which in turn enables transfer of hydraulic pressure to apparatus for venting the contents of the tubing to annulus.

Abstract: There is disclosed apparatus for use in controlling flow through a tubing string suspended and packed off within a well bore and within the annulus between the string and well bore above and below the packer by tools adapted to be lowered into and raised from landed positions within a pocket to one side of a bore through a mandrel connected as part of the tubing string for releasing the packer to be set and opening a bypass therein and for opening and closing a flapper in the bore, as well as the bypass responsive to the supply of control fluid from a remote source to the pocket.

Abstract: An annulus pressure responsive well tool includes a selectively actuatable hydraulic bypass for bypassing a pressure differential across a power piston of the tool so that an operating element associated with the power piston will remain in a chosen position during a subsequent change in well annulus pressure.

Abstract: A valve employing a coupling disk to rotate the valve member so that rotative force is applied to the valve member in a direction away from the seat during opening of the valve and/or in a direction toward the seat during closing of the valve. Closing force is provided by a spring in a dome chamber and a gas charge in the dome chamber. A float valve controls fluid entry into the dome chamber to trap the gas charge therein while permitting the introduction of liquid from a balance-closure assist line to increase the pressure of the gas charge and assist in closing the valve member.

Abstract: There is disclosed a subsurface tubing safety valve comprising a body having ports therein connecting the bore of the body with the annulus thereabout, a sleeve for reciprocating in the body between positions opening and closing the ports, and a piston which reciprocates within the sleeve, and a pair of coil springs, a first of which acts between the piston and sleeve and a second of which acts between the sleeve and body. When the sleeve is raised to its open position, the piston may be caused to move upwardly within the sleeve in response to a predetermined increase in pressure differential acting upwardly across the piston so as to compress and generate energy in both springs. As the piston moves up, the sleeve is connected to it for downward movement therewith in response to a predetermined decrease in the pressure differential across the piston to a position in which the sleeve is released by an expandable end of a bellows in response to a predetermined drop in the pressure of the well fluid.

Abstract: A mud saver valve in which a cylindrical resilient sleeve is pressed against an inner tubular member by a pressurized gas to prevent flow from above the valve to below the valve at low pressures, and which is fully opened for free flow at higher pressures.

Abstract: A hydraulically controlled apparatus responsive to changes in well annulus pressure is disclosed. The apparatus is run into a well bore intersecting an oil and gas reservoir with perforations communicating the oil and gas reservoir with the well bore. The apparatus has an associated packer to effectively seal off the perforations in the well bore. The apparatus contains a cylindrical housing with ports on the top end and bottom end, and an operating mandrel is disposed therein. A disengaging sleeve operably connected with the operating mandrel allows the ports contained on the lower portion of the cylindrical housing below the packer to be opened and closed selectively, thereby allowing communication of the reservoir pressure through the apparatus. The disengaging sleeve and operating mandrel are activated by either an increase or decrease in annulus pressure.

Abstract: Injection valve for injecting chemicals into subsurface formations penetrated by an oil or gas well, comprising a cylindrical housing (10) with seals (24A, 24B) for cooperation with well tubing (100), said housing enclosing a cylindrical chamber (1) in which a piston-like sleeve (2) is movable axially so as to cover or uncover one or more radial ports (10A) through a cylindrical wall of said housing (10). A spring (3) normally urge the sleeve (2) to a position in which the ports (10A) are covered. A collet (4) is mounted for axial displacement in a chamber extension (1A) beyond an inner end of the sleeve (2), a compression spring (5) urging the collet against said inner end of the sleeve (2).