Abstract: A well tool and method are provided for evaluating a subterranean formation through an exposed formation surface, such as the wall of a newly drilled well bore. The tool has a tubular main housing that is connectable into a well work string. A probe and a scraper are extendible from the main housing in response to a first signal of a signal set transmitted from the surface. The probe and the scraper are returnable to the main housing in response to a second signal set transmitted from the surface. The probe provides an isolated fluid conduit from the formation surface to a sensor for measuring a condition in the well. The scraper is for removing debris and for smoothing the formation surface, thereby helping to establish a sealed engagement of the probe to the formation surface. The tool can also be provided with a sampling vessel for taking samples of formation fluids obtained via the isolated fluid conduit in the probe.

Abstract: A wellbore completion system utilizes casing conveyed devices to establish a fluid communication path between a downhole formation and the casing string. Extendible pistons are mounted in the wall of the casing pipe string and are extended toward contact with the downhole formation after the casing is set. An explosive device is mounted in the pistons and includes a detonator and a shaped charge. The detonator is housed in a plug threaded into one end of the piston. The shaped charge is housed in a canister conveniently inserted into the other end of the piston. The explosives included in the system may thus be conveniently assembled at the well site. Explosive in the pistons are activated by a separately conveyed activation system which produces a pressure wave to detonate the explosives and establish fluid communication between the casing and formation.

Abstract: A formation testing apparatus and associated methods provide efficient and convenient evaluation of formations. In a described embodiment, a formation testing apparatus has a pair of relatively closely spaced apart inflatable packer elements exteriorly disposed thereon. When positioned opposite a formation, the packer elements are inflated to substantially isolate a volume of the wellbore adjacent the formation. With the packer elements inflated and sealingly engaging the formation, the elements are alternately further inflated and partially deflated to thereby alternately expand and compress the volume therebetween. The volume is in fluid communication with an interior fluid passage of the apparatus, and the alternate expansion and compression of the volume results in fluid being pumped through the fluid passage.

Abstract: This invention provides a formation evaluation tool for collecting a formation fluid in a chamber at a predetermined pressure and for maintaining the pressure of the collected fluid at a desired level during the retrieval of the chamber to the surface. The formation fluid is pumped into the chamber while a piston exposed to the hydrostatic pressure maintains the chamber pressure at the hydrostatic pressure. During retrieval of the chamber, the pressure in the chamber is maintained at a predetermined level by pumping wellbore fluid to the piston. A control unit at the surface is utilized for controlling the operation of the formation tool.

Abstract: A magnetic coupling for substantially synchronously transferring linear motion through a non magnetic barrier from a first movable element to a second movable element. The coupling comprises magnets disposed at spaced apart locations along the first element. The magnets each have a magnetization direction substantially perpendicular to a direction of motion of the first element along the non magnetic barrier. The coupling includes magnets disposed at spaced apart locations along the second element at locations corresponding to locations of the magnets op the first element. Each of the magnets on the second element has a magnetization direction inclined at an oblique angle with respect to the magnetization direction of the corresponding magnet so as to capture magnetic flux from the magnets on the first element when either of the elements is moved along the barrier.

Abstract: An injector (1) for injecting a traceable material into an oil and/or gas reservoir is lowered down into a bore hole that is in communication with the reservoir. An electro-hydraulic system is activated to inject a traceable material stored in a container into the reservoir. The injector is provided with a gland plate (7) that seals a space between the injector and the wall of the bore hole (16) in a manner that prevents traceable material from being distributed in the bore hole, but secures direct injection of the material into the reservoir. The injector is adapted to be positioned at a specific depth level in the bore hole, and to be cleaned by pressurized liquid after the injection operation is completed.

Abstract: A well logging instrument string including a first section adapted to be operated substantially in contact with a wall of a wellbore, a coupling connected at one end to one end of the first section. The coupling includes first and second flexible joints for enabling relative angular deflection between the first section and a second section. The coupling includes a biasing mechanism for urging at least one of either the first or the second flexible joints, or both, to assume their positions of maximum angular deflection. The instrument string includes a second section connected to the other end of the coupling. The second section is adapted to be operated spaced apart from the wellbore wall.

Abstract: An apparatus for perforating a wall, such as the casing wall of a well hole, taking a sample of the fluids which may be behind the wall, and subsequently sealing the perforation so formed in the wall, wherein the perforating portion, the sampling portion and the sealing portion are operably disposed in the apparatus, so as to permit all of the perforating, sampling and sealing functions to be carried out without substantial movement of the apparatus between functions.

Abstract: An improved formation testing method increases the accuracy of in-situ formation pressure measurements by characterizing the mudcake properties. Specifically, after a formation tester is lowered to a desired depth within a wellbore, a pad is extended to gently abut and seal against the mudcake without disturbing the mudcake. When pressed against the mudcake, the pad experiences momentarily higher pressures, which are measured by a probe housed by the pad. These pressures may be enhanced by briefly rejecting fluids through the probe, so as to avoid disturbing the mudcake. The probe continues to measure pressure, which eventually decreases relative to hydrostatic pressure in the wellbore, due to the flow of high-pressure wellbore fluids through the mudcake.

Abstract: This invention provides a closed-loop system for in situ testing of formation fluid conditions and for selectively collecting substantially mud filtrate free formation fluid samples at original formation conditions. The system contains an elongated member having a probe that is sealingly placed against the wellbore formation to withdraw formation fluids. A surface controlled pump controls the flow of a fluid from the formation into a flow line placed in the elongated member. A pressure sensor provides downhole hydrostatic pressure and differential pressure sensor provides difference in pressure across two fixed points across the flow line. A temperature sensor and resistivity device are utilized in a conventional manner to respectively provide downhole fluid temperature and the resistivity of the formation fluid.

Abstract: An apparatus for withdrawing fluid from an earth formation comprising an elongated housing, a first inflatable elastomeric seal adapted to expansively fill an annular space between the housing and the wall of a wellbore. The seal includes axially spaced seal lips protruding from a surface of the seal. The seal lips circumscribe the seal and define a flow channel therebetween. The flow channel includes radially spaced filler blocks which divide the channel into radial segments. Each segment further includes a flow port. The apparatus includes means for inflating the seal. The apparatus includes valves connected to each of the flow ports for connecting selected flow ports to an intake of a fluid pump and connecting selected other flow ports to a discharge port of the pump. The pump is operable in conjunction with the valves to withdraw fluid from selected flow ports and to discharge fluid into other flow ports.

Abstract: The present invention is a sample tank for storing and transporting a fluid sample withdrawn from an earth formation by a formation fluid sampling tool. The sample tank includes a storage cylinder adapted to withstand high internal pressure. The storage cylinder is selectively hydraulically connected to the sampling tool for conducting the fluid sample into the storage cylinder. A fusible metal substantially surrounds the storage cylinder. The fusible metal has a melting temperature not more than the temperature of the fluid sample, so that solidification of the fusible metal maintains the fluid sample substantially at the melting temperature of the fusible metal during solidification of the fusible metal as the tool is withdrawn from the wellbore and cooled. The fusible metal is surrounded by an outer housing which contains the fusible metal when it is in a liquid state.

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

Abstract: A ported fluid flow member has been developed in which one or more ports each is lined with a metal tube which has a portion projecting into the body member. The projecting portion may be crushed shut forming a metal-to-metal seal to seal off the corresponding port to flow. Methods have been invented for using the items with one or more of the lined ports.

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: Blowout preventers (BOP) include a tubular shell which is insertable within, and thus contained by, an upper portion of the well casing. The tubular shell includes a removable inner sealing/pressure-reducing (SPR) assembly which provides for a high-pressure seal against the exterior surface of the drill stem as well as reducing the pressure of rising subterranean gas. The SPR assembly includes a channel passageway for the rising subterranean gas in which a series of longitudinally separated transverse orificed baffles is disposed. In this manner, the pressure of the subterranean gas flowing upwardly through the channel passageways will be reduced as the gas encounters the orificed baffles. A longitudinally separated pair of split sealing blocks is also preferably disposed within the sealing/pressure-reducing assembly.

Abstract: Apparatus for obtaining horizontal and/or vertical permeability measurements through a probe having an elongate aperture. The invention uses the elongate aperture in the probe to orient fluid flow in an earth formation horizontally or vertically. The elongate aperture is approximated through the use of a single elongate opening or through the use of a group of aligned openings of varying shapes. Measurements can be taken at different orientations by including additional probe openings along more than one axis.

Abstract: This invention relates to a downhole activated centralizer for centralizing pipes in a wellbore for the exploration and production of hydrocarbons. The downhole activated centralizers are carried within either the pipe casing or the collars or both and remain generally within the maximum outward profile of the pipe string so as not to interfere with the movement and placement of the pipe string in the wellbore. The pipe string may be rotated, reciprocated and circulated which enhances the ability of the installer to place the pipe string in a deviated or long reach wellbore. Once the pipe string is in place, the centralizers may be deployed by one of several methods such that pistons mounted in openings in the peripheral wall of the pipe string move outwardly with sufficient force to move the pipe string way from the walls of the wellbore sufficient to form a complete annulus for cementing.

Abstract: This invention relates to a method and apparatus for perforating the formation in a wellbore wherein the wellbore is established for the production of hydrocarbons. The formation is perforated by explosive material carried in pistons which are carried within either the pipe casing or the collars or both and remain generally within the maximum outward profile of the pipe string so as not to interfere with the movement and placement of the pipe string in the wellbore. The pipe string may be rotated, reciprocated and circulated which enhances the ability of the installer to place the pipe string in a deviated or long reach wellbore. Once the pipe string is in place, the pistons may be deployed by one of several methods such that pistons mounted in openings in the peripheral wall of the pipe string move outwardly with sufficient force to move the pipe string way from the walls of the wellbore sufficient to form a complete annulus for cementing.

Abstract: A well probe including two offset shoes fixed outside of a tubular column and an intermediate shoe provided with a central passage having a cross section larger than a cross section of the column. The intermediate shoe is connected to a lower offset shoe by a mobile hasp. A mobile harness is adapted to be moved into and out of a lateral cavity of the intermediate shoe for enabling coupling and uncoupling of the intermediate shoe with a wall of the well. The mobile harness includes a casing for accommodating sensors and a hydraulic triggering arrangement, with the sensors and the hydraulic triggering arrangement being connected to a surface installation by cables and an electronic cartridge.

Abstract: A device is provided for installing multiple piezometers in a borehole at predetermined elevations. An inner support pipe which may be interconnected with a string of grouting pipe is utilized. A continuous fluid passageway for introduction of grout to the bottom of the borehole results by inclusion of the support pipe as an integral part of the string. A tray member is provided which carries a piezometer embedded in a layer of permeable material. The latter makes a hydraulic connection with the borehole wall. A spring assembly is adapted to move the tray outwardly and radially so as to bring the layer into contact with the borehole wall. A wire restrains the tray against the support pipe so as to permit the device to be inserted into the borehole. A messenger is inserted into the fluid passageway to sever the wires whereupon the spring expands, bringing the layer of permeable material into hydraulic connection with the borehole wall.

Abstract: A wireline tool, and process for its use, for lowering into wellbores for testing the gas pressure, and connate fluid flow rates, in low permeability oil or gas producing subsurface formations. The tool features a jet charge perforator for detonation to perforate through the wall and positively establish fluidic communication with the non damaged portion of the subsurface formation to be tested. It also includes, in the combination, a mechanism for affixing and stabilizing the tool in the wellbore at the wall of the subsurface formation to be tested, inclusive of a packer assembly for isolating from wellbore fluids the opening between the subsurface formation, created by the jet perforator, and tool test components. On blasting into the wall of the subsurface formation, the pressure in the flowline is maintained at formation pressure, avoiding formation damage.

Abstract: A method for obtaining samples of connate fluids from formations traversed by a borehole, wherein a sample test chamber is brought in communication with an isolated portion of the borehole wall, and is opened so as to allow the connate fluids to fill the chamber, and wherein the connate fluids are filtered through porous material including particles of determined sizes. The particles are bound together so as to form a rigid porous member, and have an average diameter which is a multiple of the diameter of the formation particles. Filter includes sieved gravel/sand embedded in a thermosetting resin. Alternatively, the filter includes metal bound together by superficial melting or welding.

Abstract: A pressure packer assembly adapted for positioning in a bore of a gas or oil well, and having a compressible sealing element which when actuated prevents fluid flow from below the compressed sealing element, with the packer assembly including the sealing element, having a lateral opening therethrough so that fracturing fluid passes through such lateral opening in the packer assembly into fracturing contact with the well bore. A notch gun coacting with the packer is also disclosed.

Abstract: A method and apparatus are disclosed for determining hydraulic properties of formations surrounding a borehole. In one embodiment, trial values of hydraulic properties such as vertical and horizontal permeability are selected and used to obtain computed formation pressure responses that are compared to measured pressure responses taken at a source and two observation probe positions. Trial values can then be modified to bring the computed pressure responses closer to the measured ones. An improved technique is also disclosed for obtaining the computed pressure responses.

Abstract: A tool for use downhole has an elongate body, arms movably mounted on the body and means for controlling movement of the arms between an operational position and a retracted position. Movement of the arms is controlled by a motor and a transmission, according to one aspect of the invention the arms being suspended independently of one another and in a second aspect of the invention, movement of the arms being controllable remotely from the tool.

Abstract: A tool for use downhole has means (18, 19, 20, 44) for engaging materials surrounding the hole. The engagement means (18, 19, 20, 44) are operated by hydraulic pressure controlled by a hydraulic circuit (10). A hydraulic power module (11) is provided for varying hydraulic pressure in the hydraulic circuit (10) to effect movement of the engagement means (18, 19, 20, 44). In case of failure, a dumping assembly (17) is provided to allow relief of hydraulic pressure in the circuit (10). The dumping assembly (17) includes a dump chamber (62) of variable volume, a dump valve (60) and a non-return valve (61); the hydraulic circuit being capable of being re-set downhole after dumping, there being no need to bring the tool to the surface.

Abstract: Apparatus is provided for collecting a plurality of samples of fluids in earth formations traversed by a well bore. The sampling apparatus includes an elongated body member adapted to carry an extensible and retractible fluid admitting probe which is selectively placed in sealing engagement with potentially producible earth formations. The fluid admitting probe is coupled to a fluid passage which is selectively placed into fluid communication with a fluid sample collection chamber. A selectively controllable pressure control system located in the fluid passage intermediate the fluid admitting probe and the sample collection chamber allows the flowing pressure within the formation fluid sample line to be maintained at any selected pressure level functionally related to hydrostatic pressure during fluid sample collection.

Abstract: A borehole tool member has an elongated slot with a surrounding seal for engaging the wall of the borehole for sampling fluid from the subsurface formations. A passage extends from the slot through a portion of the tool member to an upper opening which is connected to a conduit that extends to the surface. The seal surrounding the slot is forced against the borehole wall by two pistons located in two cylindrical chambers formed into the tool member. The pistons are actuated for movement outward of the tool member by fluid under pressure injected from the surface by way of a pressure control line extending from the surface to a second passage formed in the tool member and which extends to the two cylindrical chambers. Springs are provided for returning the pistons inward upon release of the fluid pressure in the cylindrical chambers.

Abstract: Apparatus is provided for collecting a plurality of samples of fluids in earth formations traversed by a well bore. The sampling apparatus includes an elongated body member adapted to carry an extensible and retractible fluid admitting probe which is selectively placed in sealing engagement with potentially producible earth formations. The fluid admitting probe is coupled to a fluid passage which is selectively placed into fluid communication with a fluid sample collection chamber. A pressure control assembly located in the fluid passage intermediate the fluid admitting probe and the sample collection chamber maintains the pressure within at least a portion the fluid passage of a predetermined proportional minimum level of formation pressure during fluid sample collection.

Abstract: Apparatus is provided for collecting a plurality of samples of fluids in earth formations traversed by a well bore. The sampling apparatus includes an elongated body member adapted to carry a telescopically extensible and retractible fluid admitting probe which is selectively placed in sealing engagement with potentially producible earth formations. The fluid admitting probe has a central passage in fluid communication with a first fluid sample chamber and a plurality of outer passages which are selectively communicated with formation fluid sample storage chambers within the body member.

Abstract: A formation tester apparatus for use in a well bore for multiple testing of pressures of earth formation fluids and the taking of a fluid sample, including pad and shoe means selectively operable for sealingly engaging a well bore. Upon sealing engagement of the pad means with the wall of a well bore, a fluid sample is ingested into an expanding chamber while its pressure is sensed. Upon completion of the pressure test, the pad means is retracted from the wall of a well bore, and the expanding chamber contracts to expel the fluid sample. The pressure test may be repeated any number of times. The expanding chamber includes a piston operated with fluid pressure used to actuate the pad means. A choke delays the application of pressure to the piston until after the pad means seals on the wall of the well bore. When a fluid sample is desired, the fluid pressure used to actuate the pad means is increased to operate a first valve means which connects the pad means of a water cushion sampling chamber.

Abstract: A duct-forming device is disclosed for use in a well completion apparatus of the kind, wherein a bore hole casing is positioned in a bore hole and duct-forming devices of alkali- and acid-resistant metal--such as steel--are secured at spaced levels to the casing in alignment with holes machined in the casing wall. In accordance with the invention, a closure device is arranged within the duct-forming device which permits flow of predetermined amounts of liquid, such as acid, from the interior of the casing through the duct-forming device and into the producing formation, while gradually being moved by the liquid into a position in which such fluid flow is prevented.

Abstract: A tool for testing earth formations in boreholes provides a failsafe function for retracting the sealing pad elements of a formation isolation device, in the form of elements operable in response to failure of downhole power supply for the tool to effect release of hydraulic setting pressure on the seal pad elements. The tool further provides a formation mini-sample chamber of variable volume with elements permitting aboveground monitoring and control of same independently of any other tool function. The mini-sample chamber control device also controls the operation of a formation fluid sample flow line valve. The tool is divided into upper and lower pivotable sections to alleviate the problem of becoming differentially stuck. A unique pivot structure incorporating sample chamber seal valve assembly, is provided. A unique sand screen device is provided to permit the tool to function when working with unconsolidated formations.

Abstract: The isolating packer unit is made up of a cylindrical measuring casing one end of which is connected by a cylindrical coupler tube to an end of a similar measuring casing, this coupler tube having a measuring port normally closed by a valve which is operable from within the tube to open the port. An elongate elastic packer tube is mounted on and concentric with each casing and is secured at its ends to the casing. When the packer unit is in a well or bore hole, the packer tubes are expanded or inflated by fluid directed thereinto to engage the wall of the well or bore hole to isolate the measuring port of the coupler tube from the portions of the well or bore hole above and below the packer unit.

Abstract: A formation tester apparatus for use in a well bore for multiple testing of pressures of earth formation fluids and the taking of a fluid sample, including pad and shoe elements selectively operable for sealingly engaging a well bore. Upon sealing engagement of the pad element with the wall of a well bore, a fluid sample is ingested into an expanding chamber while its pressure is sensed. Upon completion of the pressure test, the pad element is retracted from the wall of a well bore, and the expanding chamber contracts to expel the fluid sample. The pressure test may be repeated any number of times. The expanding chamber includes a piston operated with fluid pressure used to actuate the pad element. A choke delays the application of pressure to the piston until after the pad element seals on the wall of the well bore.

Abstract: A well tool system including a device for downhole suspension by means of conduit for engaging and penetrating the casing wall of a wellbore and introducing a fluid into the adjacent penetration. The downhole device includes an expansion piston that extends with sufficient force to seal at least one end of the device against a wellbore casing of relatively large diameter. A projectile is subsequently fired from the device to penetrate the engaged casing and provide a selected path of egress for squeeze cementing or the like therethrough. Thereafter, the device is released from its fixed position in the wellbore by retraction of the piston and retrieved therefrom. The device is disclosed with the expansion piston and method of operation therefor shown and described in several embodiments including explosive and hydraulic actuated mechanisms.

Abstract: An apparatus for treating rock surrounding a wellbore comprises a hollow elongated housing having nozzles radially mounted therein, which are projectable externally thereof. Each nozzle has a through passage communicating with the internal space of the housing to pass the flow of a fluid with an abrasive filler therethrough. The external end faces of the nozzles are shaped so as to press against the wall of the casing. Each through passage of the nozzle has a larger-diameter portion at the end thereof, facing the casing wall. The body of each nozzle has auxiliary passages, each such passage having one end thereof communicating with the larger-diameter portion of the through passage and the other end thereof communicating with the space externally of the nozzle, the auxiliary passages affording the flow of the fluid with the abrasive filler from the space defined by the said larger-diameter portion of the through passage and the adjacent casing wall, as the nozzle is closely pressed against the casing.

Abstract: A well logging instrument comprises a focus section having a focus upper guard, a center electrode and lower focus guard. The bottom section of the instrument includes a pad device having electrodes on its borehole wall-engaging surface and adapted to be urged against the borehole wall and also having a plurality of pressure relief holes formed therein to reduce differential pressure which might otherwise build up between the surface of the pad and the borehole wall. The remote electrode of the focus portion of the instrument is the armor surrounding the logging cable. The lower focus guard serves a dual function in that it is also the mini-focus remote electrode. Means are provided for measuring the potential between the focus guard and the cable armor and also between the microguard and the lower focus guard, both measurements then being sent up the logging cable to the surface electronics.