Abstract: A novel hydraulic set packer is set independently of the setting of two other straddle packers, the straddle packers being set by other than hydraulic means, such as by inflation or compression. If the straddle packers are set by inflation, a novel inflate deflate valve is associated with both straddle packers for providing an additional method to deflate the inflatably set straddle packer. If the straddle packers are compression set, it may be necessary to allow a top staddle packer to set only after the bottom straddle packer is already set, that is, the top straddle packer is not permitted to set when the straddle packer assembly is being pushed into a deviated/horizontal borehole or through a restriction in the borehole. Accordingly, a novel hydraulic ratchet, disposed above a bottom straddle packer on a tubing but below the top straddle packer on the tubing, will enable the top straddle packer to set only after the bottom straddle packer is already set.

Abstract: An input stimulus provides a necessary input to a microprocessor implemented control system. The control system may fire one or more perforating guns of a perforating apparatus or it may change the state of a valve in a well testing apparatus. The input stimuli may comprise a pressure pulse transmitted down a well annulus disposed between a tubing string and a borehole casing, a pressure pulse transmitted internally down the tubing string, an output of a strain gauge for sensing the set down weight of a well tool disposed in the borehole, or an output of an inductive coupler connected to the well surface.

Abstract: An input stimulus provides a necessary input to a microprocessor implemented control system. An output signal from the control system may fire one or more perforating guns of a perforating apparatus or it may change the state of a valve in a well testing apparatus. The input stimuli may comprise a pressure pulse transmitted down a well annulus disposed between a tubing string and borehole casing, a pressure pulse transmitted internally down the tubing string, an output of a strain gauge for sensing the set down weight of a well tool disposed in the borehole, or an output of an inductive coupler connected to the well surface.

Abstract: A piston of a well tool is disposed external to a tool housing, and within a space defined by an external sleeve and the housing, and pushes mud solids out of an open end of said space when the piston moves within the space of the tool. Due to the orientation of the tool within the borehole of an oil well, the open end of the space is subject to the force of gravity. Thus, when the piston moves downwardly within the space, mud solids disposed between the piston and the open end of said space are pushed out of the open end in response to the movement of the piston and the force of gravity.

Abstract: A well testing tool includes a plurality of valves, a plurality of well tool control systems connected, respectively, to the plurality of valves, and an electronics section connected to the plurality of well tool control systems for energizing one of the control systems thereby opening or closing a valve associated with the one control system when the electronics section of the tool detects the existance of an input stimulus transmitted downhole by an operator at the well surface. The operator need only know the particular input stimulus to transmit for a particular valve and need not know how many well tools are disposed downhole or in which tool a particular valve is disposed. The opening or closing of a particular valve is accomplished independantly of any other valves disposed in the tool.

Abstract: A multi-valve well testing system adapted to be disposed downhole in a borehole, includes a plurality of valves and a plurality of well tool control systems connected, respectively, to the plurality of valves and further includes an automatic control mode feature. The well testing system includes a controller board which comprises a microprocessor and a read only memory (ROM). The ROM has encoded therein a set of microcode which, when executed by the microprocessor, causes the various plurality of valves in the well testing system to be opened and closed automatically, without intervention from the operator at the well surface. A kickoff stimulus is required in order to begin execution of the microcode by the microprocessor. This kickoff stimulus could include a sensing, by a pressure transducer, of a predetermined bottom hole pressure, or a sensing, by a strain gauge, of a predetermined set down weight of the well testing system.

Abstract: In accordance with illustrative embodiments disclosed herein, a formation testing tool suspended in a well on a pipe string includes a valve actuator control system which responds to a command signal having a certain signature. The command signal is applied at the surface to the well annulus, and includes a series of two or more low level pressure pulses which are detected at the downhole tool, each pressure pulse having, for example, a certain peak value which lasts for a certain time. On detection of the command signal, a control system within the testing tool permits selective application of hydrostatic pressure which forces the valve actuator to shift from one position to another, thereby to open or close an associated valve element.

Abstract: In accordance with illustrative embodiments disclosed herein, a formation testing tool suspended in a well on a pipe string includes a valve actuator control system which responds to a command signal having a certain signature. The command signal is applied at the surface to the well annulus, and includes a series of two or more low level pressure pulses which are detected at the downhole tool, each pressure pulse having, for example, a certain peak value which lasts for a certain time. On detection of the command signal, a control system within the testing tool permits selective application of hydrostatic pressure which forces the valve actuator to shift from one position to another, thereby to open or close an associated valve element.

Abstract: A permanent completion tubing conveyed perforating (TCP) system including a firing head that responds to the difference between annulus and rathole pressure, has a floating piston seal that functions before the guns are dropped to communicate annulus pressure to a closed oil-filled pressure conduit system extending from the piston to the firing head. After the guns are dropped, the piston seals communication between the annulus and the production tubing bore.

Abstract: In the representative embodiment of the invention disclosed herein, a disc valve is cooperatively arranged to include a disc member of a ductile material which is transversely positioned within an enlarged chamber in the axial bore of a tubular housing and sealingly secured to the housing. A piston-actuated tubular mandrel having a forward position defining a slanted annular cutting edge with a notch on one side thereof is arranged in the housing so that as the mandrel is advanced against the disc, the inclined cutting edge will progressively sever the central portion of the disc from its peripheral portion and progressively bend that part of the central disc portion disposed in the notch outwardly to confine the central disc portion between the housing wall and the exterior of the mandrel.

Abstract: In accordance with an illustrative embodiment of the present invention, a full-bore sampler and safety valve apparatus includes a housing having a hydraulically operable mandrel assembly slidably arranged therein, axially spaced, normally open ball valve elements mounted by trunnions on said mandrel assembly for rotation from positions simultaneously opening a flow passage through said mandrel assembly in one longitudinal position of said mandrel assembly to positions simultaneously closing said flow passage in another longitudinal position of said mandrel assembly, a first actuator member fixed with respect to said housing for applying closing torque to one ball valve as said mandrel assembly is shifted toward said other position, and a second actuator member movable relative to said housing and said mandrel assembly and operable in response to rotation of said one ball valve for applying closing torque to the other of said ball valves.

Abstract: A well perforating technique utilizes a predetermined pressure difference developed at different points in the borehole to actuate the firing mechanism of a tubing conveyed perforating gun. A first embodiment incorporated as part of a well test string includes a packer for isolating a wellbore interval and a perforating gun connected in the string below the packer which is fired in response to development of a greater pressure in the annulus above the packer than in the isolated interval, thereby causing perforation at "underbalanced" conditions. A modified "full-bore" embodiment has an annular configuration firing mechanism as part of a tubing string and fires the perforating gun in response to development of a predetermined difference between the pressures at a point in the annulus and a point in the central bore of the tubing string.

Abstract: In accordance with an illustrative embodiment of the present invention, a drill stem testing apparatus includes a housing leaving a full-opening bore, and a main test valve for opening and closing the bore in order to flow and shut-in the formation interval being tested. The apparatus further includes a first port means for communicating the pressure of fluids in the bore below the test valve to a first pressure transducer, a second port means for communicating the pressure of fluids in the bore above the test valve to a second pressure transducer, and a third port means for communicating the pressure of fluids in the well annulus externally of the housing to a third pressure transducer. The outputs of the respective transducers are fed to a recording gauge so that a pressure record is obtained of the changes in fluid pressure that occur in the bore of the housing above and below the test valve as well as in the annulus externally of the housing.

Abstract: In accordance with an illustrative embodiment of the present invention, a full-bore sampler and safety valve apparatus includes a housing having an actuator mandrel slidably arranged therein, axially spaced normally open ball valve elements mounted on the mandrel assembly and cooperable with fixed eccentric pins on the housing for simultaneously closing a flow passage extending through the housing when the mandrel assembly is shifted from one axial position to another, a hydraulically operable piston on the mandrel assembly normally subject to balanced pressures, and means responsive to a predetermined pressure of fluids in the well annulus for exposing the hydraulically operable means to well pressure to cause shifting of the actuator mandrel assembly and simultaneous closing of the ball valve elements.

Abstract: In accordance with an illustrative embodiment of the present invention, a well perforating and testing system includes packer and test valve means for respectively isolating a well bore interval and controlling flow of well fluids therefrom, a perforating gun connected below the packer means, and firing means responsive to a greater pressure in the well annulus above the packer means than in said isolated interval for actuating the perforating gun so that the casing can be perforated at underbalanced pressure conditions.

Abstract: In accordance with an illustrative embodiment of the present invention, a pressure controlled reversing valve includes a housing defining a reversing port, a spring-loaded sleeve valve normally closing the reversing port, means for locking the sleeve valve in the closed position, an operator mandrel mounted for reciprocating movement within the housing, clutch means for shifting the locking means with the operator mandrel as it moves in one axial direction, means for urging the operator mandrel in the opposite axial direction, and means responsive to a series of excess annulus pressure changes for reciprocating the operator mandrel to causing shifting of the locking means by an amount sufficient to disable the same and permit the valve sleeve to open.

Abstract: In accordance with an illustrative embodiment of the present invention, a pressure controlled reversing valve for use in drill stem testing includes a housing having reversing ports that normally are closed by a valve sleeve that is mounted on a spring-loaded actuator mandrel, stop means for preventing opening movement of said actuator mandrel, a mechanical counter for disabling said stop means and enabling such opening movement only after a predetermined minimum number of pressure increases have been applied to the fluids standing in the pipe string in which the reversing valve is connected, and means responsive to a subsequent pressure increase for reclosing the valve sleeve and reactivating the stop means.

Abstract: In accordance with an illustrative embodiment of the present invention, a drill stem testing apparatus that utilizes upper and lower inflatable packer elements to isolate an interval of the borehole includes a unique pump system that is adapted to supply fluids under pressure to the respective elements in response to manipulation of the pipe string extending to the surface. The pump system includes a first pump assembly that is operated in response to rotation of the pipe string for inflating the lower packer element, and a functionally separate second pump assembly that is operated in response to vertical movement of the pipe string for inflating the upper packer element. The rotationally operated pump assembly is uniquely designed to limit the inflation pressure that is supplied to the lower packer, whereas the inflation pressure generated by the vertically operated pump can be monitored at the surface.

Abstract: In accordance with an illustrative embodiment of the present invention, a valve apparatus adapted for use in drill stem testing to apportion a pressure differential across two vertically spaced packers includes a housing mounted between the packers and having a flow passage leading from the exterior to the interior thereof, a first valve means including a spring-loaded mandrel arranged to close the passage at a preselected difference in pressures inside and outside the housing, and a second valve means that also can close the passage after a measured quantity of fluids has flowed through the passage.

Abstract: A multi-valve well testing system adapted to be disposed downhole in a borehole, includes a plurality of valves and a plurality of well tool control systems connected, respectively, to the plurality of valves and further includes an automatic control mode feature. The well testing system includes a controller board which comprises a microprocessor and a read only memory (ROM). The ROM has encoded therein a set of microcode which, when executed by the microprocessor, causes the various plurality of valves in the well testing system to be opened and closed automatically, without intervention from the operator at the well surface. A kickoff stimulus is required in order to begin execution of the microcode by the microprocessor. This kickoff stimulus could include a sensing, by a pressure transducer, of a predetermined bottom hole pressure, or a sensing, by a strain gauge, of a predetermined set down weight of the well testing system.