Abstract: A self-contained downhole apparatus for being lowered into an oil or gas well to internally record samples of at least one environmental condition comprises three body sections linearly and releasably interconnected. One of the body sections is a selected one of a plurality of transducer housing sections. The selected transducer housing section is mechanically and electrically connected to a second body section containing microcomputer-operated signal processing circuitry. The third body section contains a power supply.

Abstract: An earth well completion apparatus and method wherein a work string equipped for jet washing downhole filtration devices, such as well screens and for back washing said downhole filtration devices and containing multiple ball catcher subs which utilize the same drop ball to prevent the inadvertent operation of hydraulically powered tools as well as to permanently valve closed a portion of said work string is concentrically disposed in a production string and run in said well simultaneously. Said ball catcher sub which prevents the inadvertent actuation of said hydraulically operated tools is contained within the main fluid bore of said work string and has an expellable inner collar with an outwardly biased catcher ring which, when expelled, shears hollow shearable means thereby actuating said tool.

Abstract: A downhole shut-in tool includes in one aspect a pilot valve which when opened places a differential pressure across a piston which in turn operably engages a shut-in valve element to close the shut-in tool. An electronic timer assembly and electric drive motor are provided for controlling the action of the pilot valve. The drive motor is controlled by a load sensor which senses that the motor has stalled when an actuator engages a movement limiting abutment. In another aspect a pilot valve is provided which can selectively communicate the pressure differential across the piston so as to repeatedly open and close the shut-in valve element. Efficient methods of drawdown and buildup testing using such an automated multiple operating shut-in tool are provided. Associated automated sampling tools are also disclosed.

Abstract: Apparatus and methods are provided for measuring a parameter of a hydrocarbon-bearing well fluid sample while the sample is still in place in the well and at downhole pressure and temperature conditions. A tool is lowered into the well to a downhole location. A well fluid sample is trapped in the tool at the downhole location. While the tool remains within the well, the volume of the well fluid sample is expanded while repeatedly measuring the pressure of the trapped well fluid sample at different volumes and thereby generating pressure versus volume data for the trapped well fluid sample. From this data, various parameters such as bubble-point pressure and compressibility of the sample can be readily obtained. The apparatus is suited for drawing and testing multiple samples in succession. After each sample is tested, it is expelled from the tool so that another sample can be taken. The data can be stored for subsequent analysis at the surface or it can be transmitted to the surface for real time analysis.

Abstract: An annular safety system for a well produced by gas lift includes a packer, a landing nipple below the packer and an operating seal unit to which primary and secondary well tubings and a control line are connected. There is an inline valve in the secondary tubing and safety valve operated by the control line in a primary flow conduit in the operating seal unit. After the operating seal unit is inserted through the packer to automatically land and be locked in the landing nipple and the packer operated to anchor and seal in a well casing, flow passages are formed for conveying lift gas from the secondary tubing to around the landing nipple for lifted flow upward through the primary conduit and tubing. When the well is being produced by lift gas, and pressure in the control line is reduced purposely or by rupture of the control line, the safety valve operates to prevent upward lifted flow in the primary tubing.

Abstract: A combination perforating/gravel pack assembly includes a crossover circulation tool, a gravel pack screen, gravel pack accessories and a perforating gun which are interconnected by tubular flow conductors. External seals are located at longitudinally spaced locations along the upper end of the flow conductor string, above the gravel pack accessories and screens. External seals are also located at longitudinally spaced locations along the lower end of the flow conductor string, intermediate the screen and the perforating gun assembly. After crossover and reverse circulation are established, gravel slurry is pumped through an inner service string into the production annulus between the screen and the perforated casing. The slurry liquid is returned through a tell-tale screen upwardly through the washpipe and circulation tool, where it crosses over for return flow to the surface through a bypass annulus between the inner service string and the upper flow conductor seal assembly.

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 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: Multiple sintered metal sand screen sections are mechanically coupled to a perforated screen mandrel in an arrangement which is capable of sustaining normal bending loads associated with run-in in highly deviated and horizontal well bores, without breaking the mechanical connections or otherwise damaging or impairing the structural integrity of the sintered metal screen sections. The multiple screen sections are held under compression by end collars. Adjacent screen sections are separated by annular spacing rings and by resilient seal rings which seal the union between adjacent end portions of the sintered metal screen sections. The end collars are welded directly onto the screen mandrel, with the sintered metal screen sections being stabilized about the perforated mandrel by longitudinal compression loading, so that it is not necessary to form a weld joint on the sintered metal material.

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 two-way retrievable packer plug is installed in the production bore of a flow conductor by straight insertion, and is retrieved by a one trip straight pull operation. The plug assembly includes a core mandrel which is enclosed within a tubular latch mandrel on which an annular seal assembly is mounted for sealing engagement against the production bore of a flow conductor. A latch key is yieldably biased by a coil spring for interlocking engagement with a latch retainer lug carried on a landing receptacle attached to the flow conductor. The latch key is moveable from a radially extended position in which it is engageable against the latch retainer lug so that the latch key is blocked against axial displacement relative to the landing receptacle as the plug mandrel is inserted into or withdrawn out of the flow conductor.

Abstract: A downhole tool apparatus for use in a well includes a housing having a cylindrical chamber defined therein. A power piston is slidably disposed in the cylindrical chamber and divides the cylindrical chamber into first and second chamber portions on opposite sides of the power piston. First and second explosive charges are contained within the housing and communicated with the first and second chamber portions on opposite sides of the power piston. Firing of the first explosive charge moves the power piston in a first direction. Firing of the second explosive charge moves the power piston back in a second direction opposite the first direction. Thus, the operating power for a downhole tool is provided by selective firing of explosive charges which provide the operating pressure to move the power piston of the tool.

Abstract: In a retrievable packer adapted for service under high temperature and high pressure operating conditions, improved sealing is provided by a seal element prop surface which is radially offset with respect to the seal element support surface of the packer body mandrel. At least one seal element is supported on the elevated prop surface and is subjected to a radial squeeze in the set configuration, even though the lowermost outside seal element may be subject to longitudinal separation. The split level seal element support arrangement provides an annular pocket into which the seal elements can be retracted upon release and retrieval of the packer, thereby providing clearance for unobstructed retrieval. Upon release of the packer, a retainer collar is shifted away from a metal backup shoe, thereby providing an annular pocket into which the metal backup shoe is deflected, so that it does not obstruct the drift clearance as the packer is retrieved.

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 subsurface well flow control system includes a series of movable sleeve type flow control devices installed in a well flow conductor at various fluid-containing fracture zones, and a shifter tool movable through the conductor and operable to selectively shift any selected number of the sleeve portions of the flow control devices, in either direction between their open and closed positions, without removing the tool from the conductor. Radially retractable anchor and shifter key sets are carried in side wall openings of the tool body, and are respectively configured to be lockingly engaged with interior side surface groove sets on the body and movable sleeve portions of any of the flow control devices. The key sets are spring-biased radially outwardly toward extended positions, and an electromechanical drive system disposed within the tool body is operative to radially retract the key sets, and to axially drive the shifter key set toward or away from the anchor key set.

Abstract: The flow apertures of a perforated mandrel are temporarily sealed by a foil covering sheet which is made of a sacrificial material, for example, zinc, aluminum and magnesium The sacrificial covering sheet prevents dirty completion fluid from passing through and in and out of the screen as it is run into the hole, thereby protecting the screen from plugging. During the time the screen mandrel is temporarily sealed by the sacrificial foil covering, cleaning fluid is circulated through the work string and is returned through the annulus between the screen and the open well bore for removing filter cake, drilling debris and lost circulation material. After the annulus has been cleaned, the annulus is filled with an acid solution or caustic solution, which dissolves the sacrificial foil and opens the base pipe perforations.

Abstract: A combination packer/safety valve assembly is connectable to the bottom end of a tubing string and lowerable therewith into the casing string portion of a gas storage well to control the upward flow through the casing string of pressurized gas stored in a subterranean cavern below the casing string. In response to the delivery through the tubing string to the interior of the assembly of control fluid at a first predetermined pressure a normally closed, axially extending interior passage of the assembly is opened to permit upward flow therethrough of pressurized gas for delivery to the well surface through the casing string.

Abstract: A measuring device for measuring length of flexible line moved through the device along with tensile force in moving or stationary line. The device has a grooved counterwheel and pressure wheels pressing the line into a groove around the counterwheel and includes adjusters for adjusting the pressing force exerted by each pressure wheel on the line. A load cell mounted on the device is used to measure the resultant force on the counterwheel from tensile force in the line. A counter or counterdrive is connectible to the counterwheel shaft.

Abstract: Two embodiments of a metal valve, each having a body with flow passages and curved internal sealing surfaces and a valve member with a flow passage and external curved sealing surfaces. Both the body and valve member sealing surfaces are curved as a portion of the involute of a circle and are sealingly engageable. The valve member is mounted in the body for rotation between open and closed positions, permitting and preventing flow through valve.

Abstract: A shifting tool for sliding sleeve valves for use in oil and gas wells which has locating dogs that are used for selectively locating and engaging a shoulder inside the valve. Primary keys engage and selectively shift the sliding sleeve to an equalized position as well as prevent premature shifting to a fully open position. Also included is apparatus for selectively overriding the shifting prevention following equalization. Secondary keys lead the primary keys in the shifting direction and engage the sleeve and move it to the fully open detent position. There is also selective disengagement of the shifting tool from the sleeve valve to allow withdrawal of the shifting tool form the well. Furthermore, a method for selectively and sequentially shifting the sliding sleeve for a sliding sleeve valve from the closed to equalizing position, and then from the equalizing to fully open position is disclosed.