Abstract: An actuator apparatus for actuating a downhole well tool according to which a housing extends in the well and a tool to be actuated is disposed in the housing. A drive member is connected to the tool for operating the tool, and an actuator system is disposed in the housing and is normally connected to the drive member for driving the drive member and operating the tool. In the event the actuator system fails, an additional actuator system is disposed in the housing and is adapted to be connected to the drive member for also driving the drive member and operating the tool.

Abstract: A multi-cycle circulating sub apparatus having a control member for controlling the movement of a sleeve between a first or closed position and a second or open position. The control member is slidably mounted in a body and is moveable by fluid pressure in the body in a first axial direction relative to the body. The control member also has a spring biasing the control member in an opposite axial direction of the body. A pin is secured to either the body or the control member. A central groove, in which a portion of the pin is received, is formed in the other of the body or control member. The central groove is shaped to limit axial displacement of the control member in response to pressure variations in the body such that only after a predetermined number of movements of the control member to a first limit position is the control member able to move to a second limit position to displace the sleeve into the second position. The apparatus may also be reset many times while remaining in a downhole position.

Abstract: A circulating valve and associated methods of using same provide control of fluid flow within a subterranean well. In a described embodiment, a circulating valve includes a fluid pressure storage chamber in fluid communication with the exterior of the valve. When positioned in a wellbore, fluid pressure in an annulus between the valve and the wellbore is stored in the storage chamber. A subsequent, relatively rapid, increase in the annulus fluid pressure causes the valve to operate.

Abstract: Apparatus and associated methods provide convenient and reliable deposition of a radially deflectable blocking member relative to a downhole tool. In a described embodiment of the apparatus, a lock-out tool has mechanisms which effect latching of the tool to an internal profile of a safety valve, displacement of an opening prong of the safety valve to open the safety valve, and deposition of an expandable ring to prevent closure of the safety valve. The ring is accurately positioned by the tool and is constructed in a manner which enables it to resist relatively large axial loads, but which also enable it to be significantly radially compressed.

Abstract: Apparatus is provided which reliably and conveniently controls fluid flow through a sidewall of a tubular string. In a described embodiment, an auto-fill sub includes a check valve disposed in a housing. The check valve includes a generally tubular flexible member for sealingly engaging a sidewall of the housing to prevent fluid flow through an opening formed through the sidewall. A flow deflector may be provided to prevent abrasive wear, flow cutting and extrusion of the flexible member. Other features may include a lockout sleeve and a piston for displacing the lockout sleeve relative to the housing.

Abstract: A formation isolation valve (FIV) method and apparatus is disclosed for building a tool string of any desired length prior to lowering that tool string downhole for the purpose of performing wellbore operations during a single trip into the wellbore.

Abstract: A downhole tool apparatus (34) including a housing (42) adapted to be connected in a pipe string (30), the housing (42) having a generally cylindrical bore (44) defined therein, an operating assembly (112) disposed within the cylindrical bore (44) of the housing (42) having open and closed positions and a mandrel (142) slidably received in the cylindrical bore (44) of the housing (42) and adapted to be selectively telescoped between first and second axial positions relative to the housing (42) to manipulate the operating assembly (112) and selectively rotated between first and second circumferential positions relative to the housing (42) to selectively lock the mandrel (142) in an axial position relative to the housing (42).

Abstract: A formation isolation valve (FIV) method and apparatus is disclosed for building a tool string of any desired length prior to lowering that tool string downhole for the purpose of performing wellbore operations during a single trip into the wellbore.

Abstract: A downhole activated circulating sub is adapted to be interconnected between various tools installed on coiled tubing and placed into a wellbore; for example, between a coiled tubing/measurement while drilling tool and a downhole motor/drill bit for drilling a wellbore. The circulating sub can be repeatedly set and reset while the circulating sub is disposed in the wellbore. As a result, it is not necessary to retrieve the circulating sub to the wellbore surface for the purpose of resetting the sub. The circulating sub includes a latch mechanism which locks and latches the sub in either a set condition or a reset condition when a fluid is pumped through the circulating sub. When fluid flow through the circulating sub stops, the latch mechanism is unlocked and the circulating sub can change between the set condition and the reset condition.

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: A pressure limit valve for well tools where a valve member is moveable between a first closed portion, an open position and a second closed position. A spring for closing the valve is separated from a locking chamber which contains locking elements. The locking elements are located in a locking chamber and are held deactivated by a release sleeve which separates from the valve member in an open position. When the valve moves to the second closed position it is locked by engagement of the locking elements with a stop shoulder. In use between closely coupled inflatable packers, the valve prevents trapped pressure between the packers from affecting operation of the packer 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 cementing system where cement slurry is pumped down the annulus between the casing string and the well bore wall and then allowed to harden therein. A cement shoo on the lower end of the casing string prevents upward flow of fluids as the casing string is run, and then is opened and locked open in response to inside pressure. A normally open check valve in the casing string several joints above the cement shoo has flow passages that are closed by balls or ball discs which are suspended in a fluid spacer that is run ahead of the lower end of the column of cement slurry as it descends in the annulus.

Abstract: There is disclosed a subsurface safety valve which is adapted to be installed in a tubing string within a well bore and of a type which remains open only so long as a controlled condition is maintained. Also disclosed are several embodiments of a mechanism for holding a rotary control rod of such a valve or other apparatus in a desired rotational position to maintain it open, or otherwise in a desired state, and then releasing it, upon loss of the controlled condition, for return to its original rotational position.

Abstract: A tool is disclosed, e.g. but not limited to a wellbore cementing stage tool, which has a hollow body member with one or more lined ports through which fluid can flow from an interior of the body member to space outside the body member, e.g. to the annulus of a wellbore between an exterior surface of the tool and an interior surface of the wellbore or vice versa. The port or ports are lined with a metal tube which has a portion projecting into the body member. The projecting portion may be crushed shut forming, preferably, a metal-to-metal seal to seal off the corresponding port to flow. A hollow member is disclosed with a port through it which has a metal liner with a portion projecting from the port. Methods are disclosed for using the items with one or more lined ports.

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 flapper valve assembly for use in a flow conduit in a subterranean well, the assembly having a valve closure member pivotally connected to a floating hinge assembly that slidably engages a sleeve comprising the valve seat. A strut assembly comprising circumferentially spaced struts pivotally connected to the valve closure member away from the floating hinge member and pivotally connected to a spring guide surrounding the flow conduit is also provided, and is biased to force the valve closure member toward the closed position.

Abstract: A tubing retrievable safety valve, lockout tool and method of use are disclosed that are adapted to lock the valve open permanently and provide access to control line pressure by perforating the piston in the valve. The lockout tool comprises a track mandrel having a ramp slidably disposed beneath a punch that is adapted to penetrate the piston wall of the valve at a point adjacent to the control fluid annulus, thereby creating a protrusion adapted to lock the valve open and establishing fluid communication between the control fluid annulus and the valve bore.

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: 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: An injection valve for use in a well having a valve closure element positioned below a valve seat moving between an open position to a closed position on the valve seat for blocking off upward flow through the bore, but allowing downward flow. A flow tube is telescopically movable in the housing for controlling the movement of the valve closure member and a piston is movable in the housing and connected to the flow tube and exposed to fluid in the bore. An upwardly facing shoulder on the flow tube receives a retrievable orifice member for providing a force for fully opening the valve when fluid is injected downwardly through the bore. A retrievable lockout sleeve is provided to lock the valve open when the retrievable orifice is removed.

Abstract: An automatic timed shut-in valve for pressure transient testing of a well and the like includes a body member adapted for connection to a locking device for locating the valve at a predetermined point in a tubing string. The valve includes a clock timer and an actuator which is operable to close the valve at a predetermined time after insertion of the valve in the tubing string. Various operations may be carried out including automatic times shut-in of a well or pressure transient testing by recording at least one of pressure and temperature in the well in timed relationship to actuation of the valve so that wellbore and formation conditions can be measured upon shut-in of the well.

Abstract: A hydraulically actuated subsurface well safety valve having a first hydraulic piston and cylinder assembly for normally actuating a flow tube and controlling the opening and closing of the valve. A second lock-out piston and cylinder assembly is provided for holding the valve in the open position and a hydraulically actuated release mechanism engages the lock-out for releasing the lock-out and allowing the valve to close. A releasable and engagable latch mechanism in the second assembly releasably holds the second assembly inactive but can be overcome and reengaged for multiple operations.

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: A casing shut-in valve system (74) having a flapper valve assembly (34) and a shift head assembly (76); the flapper valve assembly (34) having an upper body member (36), lower body member (38), flow sleeve (40), valve seat sleeve member (42), flapper (54), flapper hinge assembly (56), and a plurality of spring strut assemblies (58) disposed on opposite sides of the flapper hinge assembly; the shift head assembly (76) having key housing (134) with bit sub (144) rotatably mounted in bearing (152), a plurality of outwardly biased shift keys (80), and a load equalizer plate (138) at each end of the key housing; the shift head assembly (76) being adapted to selectively open or close the valve by engaging and moving the flow sleeve (40) between defined upper and lower positions, thereby controlling the movement of flapper (54) through an angle (128) of rotation that is less than 90 degrees, and preferably about 45 degrees.

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).

Abstract: An improved lockout housing (48) and lockout sleeve (46) for a tubing retrievable safety valve (36) having cooperating lugs and lug recesses that are adapted to reduce the likelihood of premature shearing or leaking. Sets of circumferentially spaced, shearable retaining lugs (64) are alternated with sets of circumferentially spaced, shearable communicating lugs (54) that extend radially inward around the upper portion of lockout housing (48) and are preferably unitarily formed as an integral part of the lockout housing (48). First and second sets of longitudinally extending slots (62, 66) are likewise circumferentially spaced around the lower end of outside wall (68) of lockout sleeve (46), and are adapted to slidably engage the longitudinally aligned lugs (54, 64) of the lockout housing. Slots (62) aligned longitudinally with communicating lugs (54) are preferably longer than slots (66) aligned with the retaining lugs (64), and extend a greater distance up outside wall (68) of lockout sleeve (46).

Abstract: A safety valve for use in a well conduit which is automatically actuated to close when production flow impingement on a retrievable flow choke in the safety valve operating tube is sufficient. The safety valve utilizes all metal to metal seals and includes a unique roller detent mechanism, which releasably positions the operating tube in valve open position and provides snap closure of the valve. The operating tube has internal locking recesses and a metal seat. A flow choke of the size to cause safety valve closure at a selected flow rate is connected on a lock mandrel having a metal sealing surface. The lock mandrel with choke is lowered into the safety valve and operated to seal on the metal seat and lock in the locking recesses. When it is desirable to change the choke size, the lock mandrel is retrieved from the safety valve to surface.

Abstract: An annulus pressure responsive tool is temporarily deactivated so as to no longer be responsive to changes in well annulus pressure. The tool includes a tool housing with a power piston slidably disposed in the housing. A first pressure conducting passage in the housing communicates the well annulus to one side of the power piston. A reference pressure means is disposed in the housing for providing pressure to the second side of the power piston. Thus, a pressure differential is created across the power piston. Also, a selectively operable temporary deactivating means is provided so that the power piston is no longer responsive to changes in the well annulus pressure.

Abstract: A well safety valve having a flow tube telescopically controlling the movement of a valve element. A coil spring yieldably moves the tube in a direction for opening the valve and a choke bean is connected to the flow tube for controlling the closure of the valve. A spring-loaded release latch engages the flow tube yieldably preventing the flow tube from moving to the closed position. The latch is adjustable and includes a belleville spring for providing a large restraining force without undue deflection.

Abstract: Method and apparatus for introducing treatment fluid into a subterranean formation by use of a reverse jet pump located in a bypass of a tubing string. A plug in the tubing between the inlet and outlet of the bypass forces production fluid to flow through the bypass. When operation of the jet pump is terminated treatment fluid introduced into the tubing string causes a sleeve to slide down over the inlet and outlet, isolating the bypass. The plug is then forced out the tubing, leaving a clear path for the treatment fluid down the tubing and out the casing perforations into the formation. This arrangement enables rapid changeover from pumping formation fluid to introducing treatment fluid.

Abstract: A method and apparatus for operating a ball valve in a test tool string for a subterranean well, including a tubular actuator for the ball valve which is movable from a closing position of the ball valve to an opening position and beyond the opening position to a lock setting position, preventing the return of the tubular actuator to the ball valve closing position until the cycle of additional movements of the tubular actuator is accomplished. A metal-to-metal seal is provided for the ball valve and a larger than normal biasing force derived from a spring and a trapped pressurized gas is applied to the tubular actuator in its valve position to insure the integrity of the metal-to-metal seal.

Abstract: A subsurface well safety valve having a housing with a valve seat positioned in the housing and a valve closure member movable between open and closed positions. A flow tube is telescopically movable in the housing for controlling the movement of the valve closure member, a biasing member in the housing acts on the flow tube moving the valve to a closed position, and a hydraulic piston and cylinder assembly actuates the flow tube. The flow tube and/or the valve closure member are made of a light weight material, and allow the use of smaller and less expensive springs. The low weight flow tube reduces the required output of the biasing member and/or allows the valve to be set deeper.

Abstract: A lock open mechanism for downhole safety valve of the type having a valve head movable downwardly from a closed to an open position relative to the bore of a well conduit. The housing of the safety valve is provided with a first downwardly facing locking shoulder above the valve head. The upper portion of the safety valve housing is provided with a no-go shoulder and above that a second downwardly facing latching shoulder. A mandrel has a tubular locking body shearably secured to its lower end which locking body is abutable with the valve head. The valve head is displaced downwardly by incremental jar produced downward movements of the mandrel until a locking collet carried on the locking body engages the first downwardly facing locking shoulder.

Abstract: A combination circulating valve and fluid unloader adapted for connecting in a tubing string disposed within the well bore of a producing well which is closed to downward flow of fluids therethrough. The valve includes a tubular member with ports through the wall thereof having a sliding sleeve disposed around the outside surface which is also provided with ports through the wall thereof for passage of fluid into the annulus. Opening and closing of the valve is accomplished by shifting the sliding sleeve between three positions by changing the pressure of the fluids contained in the tubing string to overcome the force exerted by a spring biasing the sliding sleeve toward a first, closed position. When the pressure of the fluid is increased to a first selected pressure, the sliding sleeve is shifted with respect to the tubular member to a second, circulating position in which the ports of the tubular member are in fluid communication with the ports of the sliding sleeve.

Abstract: An inflatable packer is mounted on the bottom end of a well casing by valve housing defining an annular chamber which is in communication at its lower end with the inflatable packer. A radial port is provided in the inner wall of the annular chamber for communicating with the bore of the casing and, during run-in, such radial port is closed by a sleeve valve shearably secured in the annular chamber. Application of pressured inflation fluid to the sleeve valve causes it to shift to a position permitting inflation fluid to flow through the annular chamber to the inflatable packer. Intermediate the first sleeve valve and the inflatable packer is a second sleeve valve which is shearably secured in a normally open position with respect to fluid flow through the annular chamber.

Abstract: The bleeder comprises a hydraulically remotely controlled bleed valve (150) and device for guaranteeing that during bleeding, the gas is exhausted away from the well head zone. The bleed valve (150) is advantageously situated at the top end of the pressure lock and has a valve body (9) defining a main channel (17) of sufficient cross-section to pass to wireline tool. The bleed valve also has a gas exhaust lateral orifice (16) for being put selectively into communication with a first transverse channel (15) which opens out into the main channel (17) by a closure member constituted by a valve seat and a valve member formed at one end of a piston (5). A second transverse channel (14) puts the main channel (17) into communication with a rear face of the piston (5), where the rear face has a greater section than its valve-forming front face.

Abstract: A stage valve for stage cementing of casings in a well bore including a tubular collar and a telescopic tubular sleeve where the sleeve has a piston portion disposed in a collar chamber and the piston portion separates a sleeve port from a collar port in a lower position. In the lower position, the sleeve mechanically engages the collar and is movable to an upper position by a differential hydraulic pressure across the piston portion to an upper position placing the sleeve port and the collar port in fluid communication with one another. In moving to the upper position, the sleeve removes a barrier from a ratchet ring in the collar so that when the sleeve is moved downwardly from an upper position, a ratchet portion on the sleeve engages the ratchet ring in a lower position of the sleeve to lock the sleeve in a closed position.

Abstract: A sampler apparatus for use in a well includes a housing having a full opening bore therethrough. A first removable sample chamber for trapping a well fluid sample is removably disposed in the housing in a location such as to avoid restricting the full opening bore regardless of whether the sample chamber is in an open or closed position. Preferably a plurality of such sample chambers are provided.

Abstract: The drilling tool proposed serves for making perforations and is equipped with an exchangeable feed helix. To prevent the feed helix from being damaged if the drilling tool becomes tilted or if the feed helix is jammed, the feed helix can execute a specific stroke by means of a supporting spring, in such a way that the drill shank can rotate freely relative to the feed helix.

Abstract: A dual flapper valve assembly permits a well logging operation to be carried out after a gravel pack has been deposited without losing a large amount of completion fluid into the formation. The dual flapper valves can be closed and fractured independently of each other and selectively to accommodate a gravel pack operation, a well logging operation and a completion fluid recovery operation. The closure plate of the lower flapper valve is propped open by the wash pipe during the gravel pack operation. The lower closure plate is fractured to accommodate a well logging operation, while the closure plate of the upper flapper valve is held open by a prop sleeve. Upon completion of the well logging operation, the prop sleeve is retracted out of engagement with the closure plate of the upper flapper valve, thereby permitting the upper flapper valve to close.

Abstract: A downhole flow testing valve having a tubular housing with a valve and flow tube movable within the housing between an open position where valve ports therein are positioned in registry and a closed position where the valve ports are out of fluid communicating registry. The valve and flow tube is closed by a resultant force developed by compressed gas and opened by pressure introduced into the valve from the annulus between the valve and well casing. The normally closed flow testing shuttle valve is secured in its closed and safe condition during installation by a hydraulically locked sleeve valve. Upon fracture of a break plug by an implement dropped through the straight through flow passage of the flow tube hydraulic fluid captured within a locking chamber is released from the locking chamber by the force of a compression spring.

Abstract: Apparatus for testing a selected zone of a subterranean bore, which may comprise a subterranean uncased well bore, comprises a pair of inflatable packers mounted in spaced relationship on a tubular outer housing to define the axial extent of the selected zone to be tested. Fluid pressure passages for inflating the packers, for monitoring the fluid pressure between the inflated packers, and above and below the inflated packers, are defined by a plurality of peripherally spaced passages formed in a multi-section tubular conduit. The fluid passages in each conduit section do not extend axially beyond the ends of the particular section but communicate with peripherally spaced radial ports.

Abstract: Apparatus for retaining axial mandrel movement relative to a cylindrical housing. A cylindrical housing has an open longitudinal passageway therethrough and a circulation port disposed through a wall thereof. A valve mandrel is slidably received in the housing and is moveable between a position in which fluid may be circulated only between the passageway and the exterior of the housing, a position in which fluid may be circulated only between the exterior of the housing and the passageway and a position in which fluid may not be circulated in either direction. An annular piston is operatively connected to the valve mandrel and has a first side exposed to the pressure exterior of the housing and a second side exposure to the pressure interior of the housing to permit movement of the valve mandrel to its various positions by application of pressure to the interior and exterior of the housing.

Abstract: In a safety valve having an axially shiftable actuating sleeve operable to move a valve head from a closed to an open position, the actuating movement of the actuating sleeve is normally produced by a small diameter piston mounted on an axially extending spindle secured to the valve housing and cooperating with a primary cylinder which is abuttingly secured to the actuating sleeve. A secondary spindle and cooperating cylinder are provided which are supplied with fluid pressure by an entirely separate line extending to the well surface. The second cylinder has only abutting contact with the actuating sleeve and may be utilized to effect the movement of the actuating sleeve in the event of the failure of the primary cylinder. In a modification, a fixed cylinder housing defines a pair of secondary cylinder bores in which secondary rod pistons are slidably mounted to effect the movement of the actuating sleeve.

Abstract: A surface pipeline safety valve having a tubular member telescopically movable in the housing for controlling the movement of a valve closure member, a rod piston and cylinder assembly contacting and moving the tubular member in response to pressure in the bore of the housing in which the second side of the assembly is in communication with the atmosphere. High and low pressure responsive mechanisms for closing the valve. Seals in the assembly and high and low pressure responsive mechanisms are replaceable from the exterior of the housing.

Abstract: A choke and kill control system for stopping production of an oil and/or gas well by injecting a fluid from the outside of the well conduit into the well bore through a check safety valve. A biasing piston and cylinder assembly initially latches the valve in the open position and is actuated by a retrievable control positioned in a sidepocket mandrel. The control may be a bias valve, a rupture disc, or may be a blanking plug for maintaining the valve in the open position. The assembly may be flushed and cleaned when desired to overcome well contamination.

Abstract: In a drill string connected to a wash pipe for retrieval of a fish in a well borehole, an apparatus comprising a connected tubular member therebetween having an internal movable sleeve. The sleeve is located close over a set of bypass ports to the exterior. The ports are selectively opened or closed; when closed, the fluid flow is directed to the fish in the wash pipe. A method of washing is set forth including the steps of controlling fluid flow so that, during running in of the wash pipe over the fish, fluid is bypassed. The bypassing occurs during the fish engagement improving speed of running in up to the time the wash pipe telescopes significantly over the fish.

Abstract: The tubing tester valve of the present invention comprises a tubular housing assembly having a downwardly closing, spring biased flapper valve disposed therein near the top thereof. A tubular mandrel assembly is disposed within the housing assembly below the flapper valve, and is secured to the housing assembly with shear pins. The tubing tester valve may be permanently opened through the application of annulus pressure from the rig floor to the annulus surrounding the pipe string, which pressure moves the mandrel assembly upward to rotate the flapper valve to an open position. In order to assure that the mandrel assembly does not retract downwardly, thus permitting the flapper valve to reclose, a spring biased locking means is provided to hold the mandrel assembly in its "up" position.

Abstract: An annulus pressure responsive downhole tool includes a housing with an operating element disposed in the housing. The operating element is movable from a first element position to a second element position relative to the housing. A hydrostatic well annulus pressure referenced annulus pressure responsive first power piston is disposed in the housing and movable from a first to a second position thereof relative to the housing in response to an increase in well annulus pressure. A lower than hydrostatic well annulus pressure referenced annulus pressure responsive second power piston is disposed in the housing and is operatively associated with the operating element for permitting the operating element to move from its first element position to its second element position in response to movement of the second power piston from a first position to a second position thereof relative to the housing.