Abstract: An apparatus and method for testing the integrity of oil delivery tubing within an oil well casing includes a rupture disc holder coupled with the tubing near the lower end thereof. As successive lengths of tubing are added, the assembled tubing is subjected to a test pressure with the pressure maintained by the presence of the rupture disc within the holder. When the tubing assembly is complete, it is subjected to a higher burst pressure sufficient to rupture the disc. This opens a passage through the holder for installation of the push-pull rod and for passage of oil from the pump, which is coupled with the tubing below the level of the holder.

Abstract: A downhole choke and associated methods provide enhanced efficiency and accuracy in well sampling and testing operations due to its capability for substantially minimizing the amount of time needed to establish steady state flow conditions in a well, and the ability to sample fluids downhole at varying downhole flow restrictions. In a described embodiment, a downhole choke is operable to restrict fluid flow therethrough by applying a predetermined fluid pressure to an annulus formed between the choke and the wellbore. The downhole choke has an axial flow passage formed therethrough, a portion of which has interchangeable flow areas. The flow areas are interchanged upon application of the predetermined fluid pressure, and again interchanged upon expiration of a time delay. One of the flow areas permits substantially unrestricted fluid flow therethrough, and another of the flow areas permits restricted flow therethrough.

Abstract: A downhole valve for use within a string of tools in a well for controlling a hydraulic activation circuit. The valve has a housing with an inlet and an outlet, defining a portion of the circuit extending between the inlet and the outlet. A moveable piston within the housing in a first position provides communication between uphole and downhole parts of the circuit, and in a second position isolates the uphole and downhole parts of the circuit. A frangible member is constructed to support, in an intact condition, the piston in one of these two positions against a biasing force, and in a shattered condition enables the piston to move in response to the biasing force to the other position. A detonating member extending through the frangible member propagates a detonation wave to shatter the frangible member when desired, closing the valve.

Abstract: A gravel pack apparatus and associated method of completing subterranean wells provides convenient and economical gravel packing operations, permitting a sand control screen to be run into the well attached to the apparatus which is, in turn, attached to production tubing, and further permitting the tubing to be detached from the screen. In a preferred embodiment, a gravel pack apparatus has interoperable valve and tubing release portions. The valve portion may be closed after the gravel packing operation is completed. Closure of the valve portion activates the release portion, permitting the apparatus to be separated.

Abstract: A downhole cut-off valve used for cementing a casing string, comprising: an outer hollow body, having a top end connected at the lower end of the casing string, an inner hole, an inner surface and a projecting shoulder forming on the inner surface and extending inwardly; an inner hollow body, arranged slidably in said outer hollow body and having an inner hole, a wall with a plurality of through holes and a projection forming on the wall and below the through holes and extending outwardly, the projection being adapted to fit with the projecting shoulder of said outer body to define a preliminary position of said inner body with respect to said outer body; the longitudinal positions of the through holes and the projection being arranged in such a manner that the projecting shoulder of said outer body is located therebetween when said inner body is placed in said outer body and will at least partially cover the through holes in response to the movement of said inner body; a relief member, blocking the upper end

Abstract: A plug for actuating a movable member of a device in a wellbore includes a housing adapted to be lowered into the wellbore and a seal member mounted on the housing. The seal member is arranged to engage the movable member such that a pressure applied to the first end of the housing moves the housing and the movable member. A chamber is provided in the housing, and a pressure responsive member at an inlet end of the chamber permits fluid communication with the chamber when the pressure applied to the first end of the housing reaches a predetermined pressure.

Abstract: A subterranean well assembly and method of installation which uses a selectively rupturable flow control device to initially block flow and after rupture to allow flow therethrough. The selectively rupturable device is eccentric, in that, it withstands higher pressures without rupture in a flow direction which ruptures when lower pressures are applied to the device in the opposite direction. The rupturable device is installed in a subterranean well in the flow path between the production tubing string and casing.

Abstract: A device and method for selectively controlling the flow of production fluid through a tubing string in an oil and gas well according to which a housing is connected to a tubing string for insertion into the well, and well fluid is passed from the ground surface into the housing. The housing is provided with a plug to establish well fluid pressure in the housing to actuate a packer and/or other ancillary devices. The plug can be removed from the hosing by increasing the pressure of the well fluid in the housing above a predetermined value, thus permitting the flow of production fluid from the formation zone, through the housing and the tubing string, and to the ground surface.

Abstract: The present invention relates to tools for use in wellbores which are actuated by means of actuating balls. The invention provides a method of actuating a tool located in a wellbore, the method comprising the sequential steps of: (a) locating a frangible actuating ball (2) on a seat, the seat being provided in the tool for receiving the actuating ball (2); (b) pumping fluid down a tubing string attached to the tool so as to apply a force to the seat and thereby actuate the tool, the force being transmitted to the seat through the actuating ball (2); and (c) breaking the actuating ball (2) to permit fluid to flow through the seat. The invention has the advantage over the prior art of providing means for actuating a downhole tool with an actuating ball (2) so that the actuating ball (2) does not form an undesirable obstruction once the tool has been actuated.

Abstract: A casing annulus remediation system for overcoming problems associated with lowering a flexible hose into an annulus between strings of casing in a petroleum well by pressurizing the hose so that the hose is rigid and may be forced down the annulus. It is necessary to insert the hose through an outlet into the annulus region for brine displacement when pressure builds up in the annulus between casing strings due to leaks in the casing. Pressure build-up in the annulus is reduced by pumping a heavy liquid through the hose into the annular space experiencing the pressure build-up. A nozzle is affixed to the lower end of the hose. The hose may be inserted several hundred feet into the well. Therefore, the hose is pressurized to maintain rigidity to keep the hose from winding about the well during deployment. To keep the hose rigid, internal pressure is maintained in the hose. The nozzle is provided with a burst disk that holds the pressure.

Abstract: A downhole valve is disclosed for use in a tubing-conveyed string of tools in a well bore, constructed to be actuated to open under pressure forces by dropping a drop bar from the well surface through the tubing. The valve, deployed in the well in a closed condition, has a frangible member arranged to be broken by the drop bar to enable the valve to open. The valve opens under well pressure forces when well pressure exceeds tubing pressure, and opens under tubing pressure forces when tubing pressure exceeds or substantially equals well pressure. The valve is particularly useful when opened in conjunction with the detonation of a perforating gun for overbalanced or underbalanced well perforation. Methods of operating a string of tools including the valve are also disclosed.

Abstract: A linear indexing apparatus and associated methods of using same provide convenient operation of tools in a subterranean wellbore. In a preferred embodiment, a linear indexing apparatus has an outer tubular housing and a tubular mandrel axially slidably disposed within the housing. Two sets of slips are utilized to incrementally displace the mandrel relative to the housing. A piston associated with one of the sets of slips permits the mandrel to be incrementally indexed in response to a series of repeated applications of a predetermined differential pressure.

Abstract: An apparatus and method are disclosed for pumping segregated fluids through a tubular member, such as is required when cementing a liner into a well bore. A liner wiper plug has an internal bore formed therethrough, with a flapper valve mounted in the liner wiper plug. The flapper valve can pivot to an open position to allow fluid flow through the wiper plug, and the flapper valve can pivot to a closed position to prevent fluid flow through the wiper plug. A work string, or a stinger attached to a work string, can be positioned within the internal bore of the wiper plug, holding the flapper valve in the open position. The wiper plug can be run into the well on the work string, with the flapper valve held open, and with flow of a first fluid in progress. The wiper plug can be releasably supported from the liner. The work string is withdrawn from the wiper plug to allow the flapper valve to close.

Abstract: Methods and apparatus are provided for draining or removing well fluid from a production tubing string into a well borehole while pulling the tubing string from the well. A special length of tubing is provided near the lower end of the tubing string with a drain port communicating the interior and exterior of the tubing. The drain port is initially plugged and sealed with a knock out plug. When it is desired to remove the tubing string from the well and drain its fluid into the borehole, a drop sleeve is dropped from the surface to shear and open the knock out plug. A sleeve stop catches the drop sleeve for re-use.

Abstract: A fluid loss device has a housing, a seal assembly, a running tool, and a plug. The housing of the fluid loss device is placed in a production string before a well bore is completed. The plug is attached to the running tool, and the running tool is attached to a wash pipe.The fluid loss device is activated by lifting the wash pipe and the running tool, thereby engaging the plug with the seal assembly, engaging the seal assembly with the housing, and severing the plug from the running tool. Activation of the fluid loss device inhibits fluid communication through the fluid loss device and reduces damage to the well structure behind the fluid loss device while completion operations are performed in other areas of the well bore.The fluid loss device is deactivated by forcing the plug through the fluid loss device with mechanical force or pressure, or by chemically eroding the diameter of the plug until the plug passes through the fluid loss device.

Abstract: The apparatus and method of the present invention involve a casing or liner component that has a sliding sleeve operable therein. A plurality of ports are plugged off externally to the liner. A series of perforating charges are aligned adjacent the plugs extending from the ports which they plug. The charges may be set off hydraulically with the valve within the liner in the open or closed position, depending on the configuration. The perforating charges may be oriented differently with respect to each other to increase the zone of perforation of the formation. The plugs and charges can be distributed in such a manner as to obtain significant coverage of perforations for the zone in question.

Abstract: A downhole valve 10 opens or closes a bypass (12,13) in response to the pressure of the fluid in the valve. The valve housing body 14 is adapted for fluid communication with a tubular within a well bore. The valve bypass may be repeatedly cycled from open to closed position by selectively raising and lowering the fluid pressure. A replaceable flow restriction 18 in the valve is sized to produce a desired flow-induced pressure drop across the valve to cycle the valve with fluid flow. Differential sealing areas (11c and 15,16) are provided to cycle the valve by varying the static fluid pressure in the valve. According to the method, a flowing fluid pressure drop induced by fluid flow through the valve is used to change the state of the valve, and a subsequent change in hydrostatic fluid pressure or fluid pressure is used to return the valve to its original state.

Abstract: An apparatus and method for selectively restricting fluid flow in a well or well conduit. A dissolvable core material is positioned in the well and is isolated from the well fluids with an inpermeable sheath. The sheath is punctured with a control mechanism or other device so that the sheath is breached. The fluid dissolves the core material and permits fluid flow through the well or well conduit. The sheath can be punctured by pressurizing the well fluid, or by controlling the fluid pressure to activate a pressure sensitive control mechanism.

Abstract: A subsurface safety valve has a tubular valve housing, a valve closure member movable between an open and a closed position, an axially shiftable flow tube for opening the valve closure member, a spring for biasing the flow tube to a closed position, a piston and cylinder assembly to move the flow tube to an open position, and a plug inserted within an opening in the valve housing. This opening is in fluid communication with the piston and cylinder assembly. The plug is adapted to be displaced from the opening to lock out the safety valve, and to establish secondary hydraulic fluid communication with an interior of the safety valve in order to operate secondary tools, such as wireline set secondary valves, inserted into the locked out safety valve.

Abstract: The invention discloses an apparatus for storing one or more constituents in a downhole tool. The constituents are segregated from each other until such time as the tool is actuated. At that time, the constituents are forced from their storage position and mixed as they are pushed from their storage position. The resultant mix is then directed to the location where the mixture will finally be placed for eventual solidification. The apparatus and method are useful for inflation of bridge plugs or external casing packers, as well as other downhole applications. Significant time is provided for the surface operator prior to initiation of the constituent elements by segregating the ingredients until shortly before they are mixed and directed to their final destination. Should a problem arise prior to mixing, the unmixed ingredients can be withdrawn from the wellbore.

Abstract: An apparatus and method for controlling the pressure at which a fluid is introduced into a well penetrating a subterranean formation. The apparatus comprises a blow out sub having a sealed chamber between two plugs. The chamber is filled with a fluid at a known pressure. Thus, the pressure required to release the first plug is independent of the pressure in the well below the sub. The sub is attached to a tubular and positioned within the well. The first plug is then released upon application of a predetermined pressure fluid pressure, and the second plug is released upon application of a lesser pressure. The blow out sub may additionally comprise a tube forming a channel through the first plug, the chamber, and the second plug, with a means for controlling fluid flow through the channel. A first fluid may be introduced into the well via the channel prior to releasing the first plug.

Abstract: A perforation trigger bypass conduit assembly (10) for a well perforation gun (17) positioned in a well casing (12) at a down-hole location below a tubular completion assembly (16). A pressure sensing device (20) senses a detonation pressure of fluid communicated from a pump (21) through bypass conduit assembly (10) to the sensor (20). The sensing device (20) triggers the gun upon sensing a pressure surpassing a predetermined value, which perforates the casing (12). The bypass conduit assembly (10) is formed to enable blocking of the bypass conduit assembly (10) after triggering of the perforation gun (17) to prevent pumping of production and power fluid back into the formation upon severing of a portion (34) of the conduit assembly (10). Blocking can be effected by removing a member (25) which contains a passageway (51) forming part of the bypass conduit assembly (10) and replacing the removable member (25) with a passageway-free insert member (35).

Abstract: A method and apparatus for cementing a casing string utilizes a port collar which may be hydraulically opened and mechanically closed, and permits the passage of downhole tools through the port collar, without opening the port collar.

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: An operating well such as an oil well is provided with a safety valve in the tubing thereof. A control cartridge controls the safety valve under the command of control signals transmitted from the surface. The control cartridge includes a housing mounted in the tubing and a receiver for receiving signals transmitted from the surface. A power supply is provided in the housing and is connected to an electronic control system, which control system is also connected to the receiver. A hydraulically operated actuator controls the safety valve, and a source of hydraulic fluid is provided in the housing and connected with the hydraulically operated actuator for operating the actuator. The source of hydraulic fluid is also connected to the power supply for operation thereof.

Abstract: The present invention provides a cementing tool for cementing multiple stages within a well. The assembly includes a housing assembly which defines one or more cementing ports. A first sleeve assembly is retained within the housing and is movable from a first position, where the sleeve covers the port, and thereby precludes fluid flow therethrough, to a second position wherein the sleeve opens the cementing port. The apparatus also includes a second sleeve assembly which is movable from a first position away from the cementing port to a second position wherein the sleeve assembly covers the port. The first sleeve is cooperatively configured with the housing assembly to provide engaging surfaces which resist rotation of the first sleeve relative to the housing. Additionally, the first sleeve and the second sleeve assembly are configured to limit relative rotation when the two pieces are longitudinally adjacent one another.

Abstract: Washing tool for removing internal deposits in tubing parts and components in wells for oil or gas production, wherein the tool is to be run on coiled tubing and to be operated by fluid pressure. The tool comprises a main body (10) provided with discharge nozzles for discharging a washing fluid, and a valve member (12) which is axially movable within the main body (10) under pressure actuation and against a spring force (24), for opening one or more of the discharge nozzles. An external valve member (14) at an upper portion of the main body (10) is arranged for axial movement against the action of a spring (15A) urging the external valve member towards a position for blocking the fluid pressure from above.

Abstract: A production valve includes an outer housing having a production port, a piston disposed within the outer housing and adapted to move from one position to another position, a frangible breakup element supporting the piston in the one position, and a detonating cord adapted for propagating a detonation wave passing through the center of the piston and the breakup element. The detonation wave shatters the frangible breakup element when the detonation wave, propagating within the detonating cord, passes through the breakup element. When the breakup element shatters, the support provided to the piston by the breakup element is removed. When the support provided to the piston by the breakup element is removed, the piston moves from the one position to the other position in response to either tubing pressure or rathole pressure or both, and the production port of the production valve opens when the piston moves to the other position.

Abstract: A safety valve landing nipple selectively provides a pin for closing communication in the bore between the first control line and the safety valve control line so that communication between the first control line and an insert safety valve in the landing nipple housing is achieved by use of a rotary member. A rotary shifting tool is used to rotate the rotary member so that a cam sleeve pushes a poppet pin to form a metal to metal seal with a fitting adaptor connecting the first control line and the safety valve control line so as to provide communication between the surface control line and the internal bore of the landing nipple.

Abstract: Hydraulic fractures are initiated or extended into fluid-producing earth formations from a cased well by filling a space within the casing adjacent the formation zone of interest with liquid which extends into a tubing string and forming a pressure gas charged portion of the tubing string by introducing pressure gas or liquid into the tubing string to compress a column of gas therein to a pressure which exceeds the formation fracture breakdown pressure. By perforating the casing or, if perforations already exist, releasing a frangible disk type closure interposed in the tubing string, the gas charge in the tubing string forces fluid into the formation at sustained pressure and flow conditions not attainable by surface pumped fracture fluids.

Abstract: A method and apparatus for isolating a zone (12) of a wellbore (14) penetrated by a casing (16) and then opening ports (28) in the zone (12) for extraction or injection of fluids is provided. The zone (12) is isolated by inflating jackets (42) and then closing a safety valve (38) by sliding a sliding member (44) relative to a first conduit (46). The ports (28) are opened by sliding a piston (80) of a sliding sleeve valve (76) so that openings (84) therein align with the ports (28). The invention provides improved zone isolation and reduced wear of seals (86) in the sliding sleeve valve (76).

Abstract: A safety valve landing nipple selectively provides communication between a surface control line and the internal bore of said landing nipple by use of a rotary member. A rotary shifting tool is used to rotate the rotary member so that a cutting means shears the end of a shearable plug in the wall of the landing nipple, so as to provide communication between the surface control line and the internal bore of the landing nipple. A method of providing communication within a landing nipple between the surface control line and the internal bore of the landing nipple by use of the rotary shifting tool and a rotary shifting tool having a rotatable outer mandrel means, an inner mandrel means, a travel means and a diametrically retractable means.

Abstract: A propulsion apparatus is provided for attachment to a selected tool for propelling and positioning the tool in a tubular member in response to fluid pressure in the tubular member and includes a tubular mandrel terminating in a lower free end, a tubular sleeve disposed over the mandrel and adapted for coaxial sliding movement with respect thereto, a cup assembly mounted on the sleeve and cooperating therewith and with the fluid pressure exerted within the tubular member for translating fluid differential pressure developed across the cup assembly into preselected propelling forces, and sleeve retaining means for cooperating with the sleeve and mandrel for positioning and retaining the sleeve in a first position with respect to the mandrel and transmitting the propelling forces to the mandrel and attached tool for propelling and positioning the tool to selected locations within the tubular member.

Abstract: A travelling disc valve assembly, comprising a length of tubing lowered down a cased wellbore; a crossover tool secured to the lower end of the length of tubing; a length of wash pipe secured to the lower end of the crossover tool; a disc valve assembly secured to the wash pipe and positioned to a lower circulation position in the well bore; a disc valve secured in a bore of the assembly; a shearing device in the upper portion of the assembly for shearing off the connection between the wash pipe and the disc valve assembly, when the disc valve assembly is in an upper position, providing a way to prevent fluid from flowing into the formation below the disc valve and to prevent production flow to the surface; and a rupturer/disengager to rupture and/or disengage the disc valve at a predetermined time so that the production within the formation is allowed to flow through the assembly bore to the surface.

Abstract: A bypass valve for bypassing well fluids, and method of use thereof. The valve comprises a tubular housing defining a bypass port therethrough with an inner sleeve mandrel defining a bypass port initially aligned with the bypass port in the housing. The valve also comprises a power mandrel slidably disposed within the housing such that, as weight is set down on the power mandrel, pressure is increased in a first oil chamber which has a rupture disc in communiction therewith. When the pressure reaches a predetermined level, the rupture disc ruptures so that the oil chamber is emptied into the well annulus. This allows the power mandrel to move and strike an operating mandrel which is also slidably disposed in the housing. The jarring force shears a shear pin which allows the operating mandrel to move a floating piston disposed in a second oil chamber. A metering cartridge restricts flow of fluid out of the second metering chamber, thereby providing a time delay for movement of the operating mandrel.

Abstract: A method of cementing oil well casings and a cementing tool used when performing the method are provided. A novel top cementing plug functions in a conventional manner during proper oil well casing cementing operations, but if inserted into the oil well casing in error, allows cement to be pumped through it. The top plug includes an outer, hard rubber casing having vertically spaced fins formed about its circumference. A central passage is provided through the outer casing and receives a cylindrical, metal sleeve. In one embodiment, a bore is formed in a portion of the metal sleeve to define a shoulder within the sleeve. The bore receives a cylindrical housing which carries a spring loaded, ball valve mechanism. The valve mechanism includes an annular spring retainer which rests on the shoulder. One end of a helical spring within the housing contacts the retainer while the other end of the spring biases a ball against an annular flange at the top of the housing to seal the passage.

Abstract: An expendable plug is shown for use in a well bore tool for controlling the flow of well bore fluids from a production zone to the well surface. The plug is located within a tubular housing which is made up in a well tubing string having an internal bore with a predetermined minimum internal diameter. The plug initially closes off the internal bore of the tubing string at a selected location. An actuator is triggered by an appropriate signal to expend the plug of expendable material, and to remove the plug from the internal bore of the tubing string, whereby fluids in the surrounding earthen formation are allowed to flow up the tubing string to the well surface.

Abstract: In the disclosed pressure operated valve, a sleeve valve controlling flow between outside and inside the valve is releasably connected in a housing when the sleeve valve is in open position. Pressure on a ball sealingly engaging the sleeve valve operates the sleeve valve from open to latched closed to disconnect positions and expends the sleeve valve from the housing.

Abstract: A pressure responsive below packer valve apparatus which allows operation of a below packer valve through application of pressure to the wellbore annulus above the packer. The valve apparatus includes a crossover located in a tool string above the packer which communicates upper annulus pressure to a conduit inside the tool string. This conduit communicates annulus pressure to a valve mechanism below the packer. A selectively releasable mechanism such as a rupture disk communicates pressure to the valve mechanism once a threshold pressure is reached, thereby facilitating operation of the valve mechanism through application of annulus pressure.

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 multiple stage inflation packer with secondary opening rupture disc. The inflatable packer comprises a case with a closing sleeve, an opening sleeve and a releasing sleeve therein. An opening plug is dropped into the casing string and is allowed to free fall, or is pumped down, to actuate the opening sleeve to allow inflation of the packer element. A back check valve prevents the packer from deflating. After the packer is inflated, additional pressure is applied which ruptures a rupture disc to open a port to the well annulus above the set packer element. Cementing may be carried out through this port, and after the cementing operation, a closing plug is pumped down the well casing behind the cement to actuate the releasing sleeve and move the closing sleeve to seal off the ports. Another check valve insures that pressure is equalized on both sides of the rupture disc as the packer is run into the well bore.

Abstract: A gravel packer and service tool combination for use in subterranean wells operates sequentially to lock and seal the packer in the well at a producing formation, release a mechanical connection between the packer and service tool, and open a passage through which gravel packing can be performed. Each operational step can be performed in primary and secondary fluid pressure-responsive modes of operation. The secondary mode of operation can be employed in the event the primary mode of operation fails.

Abstract: An equalizing blank valve apparatus for use in a sidepocket mandrel in an underground well. The apparatus comprises a first body member and a second body member. The first body has a chamber therein, and the second body member has a proximal end, a distal end, a first orifice located proximate said proximal end, a second orifice located proximate said distal end, and a passageway therethrough communicating with the said first and second orifices. The second body member is configured such that said proximal end of the second body member and said first orifice are telescopically insertable into the chamber in the first body member. Means cooperating with the first and second body members is provided for substantially sealing said first orifice when said first orifice is inserted into the chamber in the first body member. Means is also provided for preventing said proximal end of the second body member from being removed from the chamber in the first body member.

Abstract: Apparatus is disclosed for use in placing cement within the annulus between a casing string and a well bore in which the casing string is suspended, such apparatus including a stage collar connectible as part of the casing string and having a packing element mounted thereon and adapted to be inflated into engagement with the well bore, one or more side ports through which cement may be circulated into the annulus above the packer, tubular members or sleeves for opening and closing the ports following inflation of the packing element.

Abstract: An apparatus and method are disclosed which are utilized in oil wells incorporating a reciprocating pump. The improvement is for the situation where the typical sand release apparatus has failed to clear a sand lock. The disclosed apparatus is such that the rotation of the two telescoping sleeves relative to each other is restricted thereby allowing the tool string to be unthreaded at a reverse thread at the top of the sand release apparatus. In this way, the apparatus allows removal of the tool string above the location where the tool is locked through rotation in a direction opposite of that normally used to unthread tool strings.

Abstract: A system for controlling flow in a well conduit including a landing nipple in the well conduit and a standing valve, which after landing in the landing nipple may be retrieved or expended from the landing nipple. The standing valve permits upward flow and prevents downward flow through the landing nipple and conduit and has a resilient seal which expands into a groove in the landing nipple to provide limited resistance to upward flow moving the standing valve upwardly out of the landing nipple. Sufficient weight on the standing valve or pumping down the conduit with sufficient pressure releases a landing ring on the standing valve to retract, permitting the standing valve to be moved downwardly and expended out of the landing nipple.

Abstract: The present invention achieves a more reliable multiple fracturing of a subterranean formation by inserting high pressure tubing and isolating a portion of the wellbore (including the formation of interest and an end portion of the tubing) with packers. Near the end of the tubing is a closable end and a rupturable plenum holding a sufficient volume of pressurized gas to produce a pressure ramp sufficient to cause multiple fractures in the isolated portion when the plenum is ruptured. The closable end is closed after filling the isolated portion with a fracture fluid and proppant. The rupturable means is provided by at least one rupture disc. Multiple discs can provide a step wise pressure rise ramp to tailor the multiple fracture producing pulse. By providing a known volume of pressurized gas and rupture discs, a controlled pulse loading can be achieved.

Abstract: A valve in a tool may be opened and closed by sequential application of a first predetermined annulus pressure and a second predetermined annulus pressure. A first rupture disc ruptures when the first predetermined annulus pressure is applied to the well annulus thereby allowing such pressure to be applied against a surface of an operator and moving the mandrel. This moves a yoke connected to the valve, opening the valve. A second rupture disc ruptures when the second predetermined annulus pressure is applied to the well annulus thereby allowing such pressure to be applied against a surface of a collet mandrel, moving the collet mandrel in a direction opposite to the direction in which the operator mandrel originally moved. Since the collet mandrel is connected to the operator mandrel and to the yoke, movement of the collet mandrel in the opposite direction moves the operator mandrel and the yoke in the opposite direction, thereby closing the valve.

Abstract: A hydraulic safety joint for use in a downhole tool string. The hydraulic safety joint includes a mandrel assembly slidably disposed in a case assembly such that a chamber is defined therebetween. The chamber is filled with a volume of fluid so that the mandrel is held in a first operating position. When in this first position, the mandrel is in splined engagement with a nipple at the lower end of the case assembly. Upon application of a predetermined tensile load on the tool string, a rupture disc in communication with the fluid chamber is ruptured so that the fluid is vented therefrom. When the pressure is thus released, the mandrel assembly is moved to a second position in which it is further extended from the case assembly. In this position, the mandrel assembly is no longer in splined engagement with the nipple, but a series of lugs prevents relative rotation between the mandrel assembly and an upper portion of the case assembly.

Abstract: A well completion assembly is constructed to be run on a tubing string into a well. The well can be gravel packed and subsequently opened to production without removing the tubing string from the well. The well completion assembly includes a packer, and a screen located below the packer. A gravel packing and production control assembly is located between the packer and the screen for initially permitting flow of gravel packing slurry down the tubing string and into a lower well annulus surrounding the exterior of the screen, and for subsequently permitting production of well fluids through the screen into the interior thereof and up through the tubing string without tripping the tubing string out of the well.