Abstract: In the representative embodiment of the new and improved apparatus disclosed herein, a so-called "stuck-point indicator" or "freepoint-indicator" tool includes a deformation-responsive sensor tandemly supported between upper and lower selectively-operated tool anchors of a unique arrangement which, in the preferred embodiment of the tool, are cooperatively arranged to be sequentially engaged with longitudinally-spaced wall portions of a string of well pipe believed to be stuck in a well bore. In the disclosed embodiment of the tool, each tool anchor respectively includes a set of pivoted anchor members and actuating links adapted to swing the anchor members outwardly into anchoring engagement with the pipe wall for securing the tool against longitudinal movement in the pipe string.

Abstract: In the representative embodiment of the new and improved apparatus disclosed herein, a so-called "stuck-point indicator" or "freepoint-indicator" tool includes a deformation-responsive sensor tandemly supported between upper and lower hydraulically-operated tool anchors cooperatively arranged to be sequentially engaged with longitudinally-spaced wall portions of a string of well pipe believed to be stuck in a well bore. In the preferred embodiment of the tool, each tool anchor respectively includes a piston actuator which, upon application of a predetermined pressure as developed by a hydraulic-control system on the tool, operates to retract a set of movable anchoring elements and, upon a reduction in that hydraulic pressure, is biased by a spring to extend the anchoring elements.

Abstract: In the representative manner of practicing the new and improved method disclosed herein, a so-called "stuck-point indicator" or "freepoint-indicator" tool including a unique deformation-responsive sensor tandemly arranged between unique upper and lower tool anchors is positioned in a string of well pipe believed to be stuck in a well bore. The tool is then moved to a selected depth location in the pipe string and, in keeping with the principles of the present invention, operated so that the upper anchor is engaged with the pipe string wall before the lower anchor is engaged. Thereafter, upon application of forces to the upper end of the pipe string, independent measurements are produced by the sensor which are respectively representative of tensional forces and torsional forces acting on that portion of the pipe string between the upper and lower anchors.

Abstract: In the representative embodiment of the new and improved apparatus disclosed herein, a so-called "stuck-point indicator" or "freepoint-indicator" tool includes a unique deformation-responsive sensor tandemly arranged between upper and lower hydraulically-operated tool anchors which, in the preferred embodiment of the tool, are cooperatively arranged to be sequentially engaged with longitudinally-spaced wall portions of a string of well pipe believed to be stuck in a well bore. In the disclosed embodiment of the tool, the new and improved sensor is arranged as an elongated body tandemly interconnecting the tool anchors and having upper and lower portions thereof cooperatively arranged for being preferentially deformed in response to tensional forces and torsional forces acting on the body.

Abstract: In the representative embodiment of the present invention disclosed herein, a nuclear-magnetism logging tool is arranged with at least its polarizing and detecting coil isolated in an enclosed chamber containing a uniquely-treated hydrogenous oil and preferably coupled to a suitable compensating system operatively arranged for responding to borehole pressure and temperature conditions. In particular, a selected, minor amount of a ferromagnetic colloid is dispersed in the oil in a sufficient concentration for uniquely effecting a controlled decay of nuclear magnetic noise signals from the coil-isolating oil, with this decay being of selected rapidity sufficient to avoid interference with the measurement of nuclear magnetic measurement signals from earth formations.

Abstract: In the representative embodiment of the apparatus of the present invention disclosed herein, a plurality of outwardly-biased bow springs are disposed around the lower end of the body of a spinner-type flowmeter and cooperatively arranged for centering at least that portion of the tool body in a well bore. The upper ends of the bow springs are pivotally secured to the tool body and their lower ends are coupled together below the body and adapted for longitudinal movement in relation thereto. To maintain the bow springs at a uniform spacing from the tool body when the flowmeter is in a deviated well bore, a corresponding number of rigid arms are pivotally coupled to the mid-portion of each spring and extended upwardly to a pivotal connection on a downwardly-biased collar which is slidably mounted on the tool body below the spring pivots. The spinner is provided with pivoted blades which are cooperatively arranged to be extended and retracted in response to the expansion and contraction of the bow springs.

Abstract: In the representative embodiments of the present invention disclosed herein, new and improved termination assemblies for multi-conductor electrical cables are manufactured by first molding a unitary fluid barrier around the cable conductors for integrally bonding or fusing this barrier around the conductor insulating sheaths so as to block fluid-leakage paths within the barrier and along the exterior of the conductor sheaths. The forward face of the barrier and the rear face of the contact support member of an electrical connector are also specially prepared so that as a selected thermosetting polymer, such as an unvulcanized elastomer, is subsequently molded to form a body individually surrounding each of the conductors extending ahead of the barrier, the now-vulcanized elastomer will be bonded to both the contact support member and the fluid barrier so to block fluid-leakage paths within the body and ahead of the fluid barrier which might otherwise intercommunicate the interiors of these sheaths.

Abstract: In the representative embodiments of the safe-handling arming apparatus of the present invention disclosed herein, a spring-biased indicator is cooperatively arranged on an enclosed-carrier perforating gun for visually representing whether an obscured or secluded detonator enclosed within the carrier is either in an ineffectual or "safe" status or is in an effective or "armed" status in readiness for detonating one or more shaped explosive charges in the gun. In one embodiment of the new and improved arming apparatus of the present invention, a unique arrangement is provided for releasably retaining a selectively-movable detonator in either of two predetermined operating locations. In another embodiment of the invention, the detonator is instead fixed and isolated by a selectively-movable barrier whose presence or absence is shown by the indicator.

Abstract: In the representative embodiments of the apparatus of the present invention disclosed herein, a plurality of outwardlybiased bow springs are disposed around a tool body and cooperatively arranged for centering the tool body in a well bore. The upper ends of the bow springs are pivotally secured to an intermediate portion thereof and their lower ends coupled together for longitudinal movement in relation to the lower portion of the body. To maintain the bow springs at a uniform spacing from the tool body when the tool is in a deviated well bore, a corresponding number of rigid arms are pivotally coupled to the mid-portion of each spring and extended upwardly to a pivotal connection on a collar which is slidably mounted on the tool body and biased downwardly. Diameter-measuring devices are cooperatively arranged on the tool body for operation in response to the expansion and retraction of the bow springs.

Abstract: In the representative embodiment of the present invention disclosed herein, a first ported or grooved signal-producing member is coaxially disposed within the apparatus for dividing drilling fluids flowing through the drill string into two or more longitudinally-directed streams or jets. A second ported or grooved signal-producing member is coaxially arranged in the apparatus adjacent to the first member and adapted for rotation in a transverse plane to cyclically obstruct the fluid jets for developing an alternating or cyclic acoustic signal of a desired frequency in the drilling fluid stream.

Abstract: In the representative embodiment of the invention herein, delicate instruments and electronics circuitry used for obtaining downhole measurements are mounted on an elongated support or chassis which is removably disposed within a tubular housing and uniquely restrained from movement in response to shocks and vibrations which might otherwise damage or destroy the components. In this preferred arrangement, at least one set of angularly-disposed transverse rollers of a somewhat-resilient material is mounted on the chassis and respectively arranged for being slightly compressed and rollingly engaged with the internal wall of the tubular enclosure as the chassis is inserted into the enclosure.

Abstract: In the representative embodiment of the new and improved apparatus disclosed herein for positioning acoustic well-logging tools, outwardly-bowed elongated spring members of a wear-resistant metal are cooperatively spaced around the body of an acoustic-logging tool and arranged as required for maintaining the tool substantially centered within a well bore. To at least minimize or significantly attenuate the acoustic noise inherently generated by the rubbing of the outward faces of the spring members along the well bore walls which noise may otherwise unduly interfere with the reception of the acoustic logging signals, the inward faces of at least the mid portions of the several spring members are respectively covered with a composite material including an elastomer containing a substantial number of small embedded particles or interspersed balls of a sound-absorbing material such as lead.

Abstract: In the representative embodiment of the present invention disclosed herein, this new and improved perforating apparatus includes a plurality of encapsulated shaped explosive charges having their forward ends respectively fitted and threadedly secured in a facing relationship along the concave rear face of an elongated steel carrier strip of a unique design having its forward face complementally shaped for accommodation within a given size of well bore piping thereby allowing the largest possible mass of explosive to be disposed in each capsule. To assure the proper installation of the detonating cord, the rear portions of the two-part charge capsules are cooperatively arranged in a unique fashion so as to be rotatably positionable in relation to their forward portions for facilitating proper alignment of transversely-oriented cord-receiving openings provided in the base of each capsule.

Abstract: In the representative embodiment of the present invention disclosed herein, this new and improved perforating apparatus includes a unique elongated carrier strip of a ductile steel carrying encapsulated shaped explosive charges having their forward ends fitted and snugly secured against the concave rear face of the strip by means of externally-threaded axial projections respectively threaded into tapped charge-mounting holes closely spaced along the carrier. The forward face of the carrier strip and the rear portions of the capsules are complementally shaped for accommodation within a given size of well bore piping thereby allowing the largest-possible mass of explosive to be disposed in each capsule.

Abstract: In the several representative embodiments of the new and improved methods disclosed herein, a cable-suspended spinner-type flowmeter is successively lowered and raised at selected speeds in a well bore containing one or more flowing fluids whose velocity or flow rate are to be determined. In one manner of practicing the invention, the flowmeter is passed back and forth through a lower static well bore interval for establishing the response of the tool at zero flow rates. In this way the output measurements obtained from the runs through the higher or dynamic intervals can be uniquely correlated for accurately determining the velocity and flow rate of the well bore fluids in each dynamic interval independently of differences in fluid viscosity.

Abstract: In the representative embodiment of the new and improved apparatus for testing earth formations disclosed herein, fluid-admitting means are sealingly engaged with a potentially-producible formation and a selectively-movable chamber is expanded to draw mudcake and other plugging materials from the isolated face of the formation into the receiving chamber. Thereafter, the chamber is shifted to communicate the screened entry port of the fluid-admitting means with the isolated formation so as to retard or prevent the erosion of loose formation materials as the formation is tested. When the testing is completed, the chamber is cleared and returned to its initial port-closing position and the fluid-admitting means disengaged to ready the apparatus for subsequent operations.

Abstract: In the representative embodiment of the present invention disclosed herein, shaped charges adapted for installation in a typical end-loaded carrier are respectively provided with a domed annular retainer member of a thin, but substantially rigid and stiff, material which is coaxially disposed over the forward end of each charge. A smaller-diameter externally-tapered sleeve of a somewhat yieldable or deformable material is cooperatively arranged for positioning on each domed retainer member once its associated shaped charge is installed in the carrier facing and aligned with a lateral port therein. Then, as a port plug having an internally-tapered recess is installed in the port and telescopically forced over the sleeve, the forward portion of the retainer sleeve will be laterally compressed for securing the shaped charge in position with little or no inward or axial deflection of the domed retainer.

Abstract: In the representative embodiments of the present invention described herein, a drilling mud is circulated through a drill string at a sufficient rate to effectively operate an impeller-driven electrical generator arranged on a tool coupled in the drill string for supplying power to downhole electrical circuits and one or more downhole condition-measuring devices on the tool. By selectively controlling the flow of drilling mud past the impeller in accordance with the conditions being monitored by the condition-measuring devices, data-encoded acoustic signals are produced in the circulating fluid and transmitted to the surface for detecting and decoding as power is simultaneously supplied to the downhole system by the generator.

Abstract: In the representative embodiment of the present invention disclosed herein, new and improved pipe-inspection apparatus for examining oilfield piping includes, along with other flaw-inspection devices, a flux-leakage inspection device uniquely arranged for detecting minute magnetic-flux anomalies which are indicative of metal defects such as cracks, pits, holes and the like. In contrast, however, to the prior-art high-intensity electromagnetizers typically having cores of minimum magnetic reluctance, the unique pipe-inspection apparatus of the present invention instead employs an electromagnetizer having a core of a substantial length and minimum cross-sectional area to specifically make its reluctance relatively large in relation to the combined magnetic reluctances of the magnetized piping wall and the annular clearances between the piping wall and the magnetizer pole pieces.

Abstract: In the representative embodiment of the new and improved formation-testing apparatus disclosed herein, a wall-engaging sealing pad is arranged around the forward end of a normally open tubular probe which is adapted to be placed in communication with an adjacent earth formation and carries an extendible filter probe coaxially supported therein by a tubular valve member. If a formation being tested is relatively incompetent, the filter probe will be advanced into the formation without allowing further erosion of loose formation materials with the valve member acting to block communication through the outer probe. Alternatively, should a formation being tested be relatively competent, the filter probe will remain in its normal retracted position and the valve member will cooperatively block communication through the filter probe and instead provide an unrestricted flow passage through the outer probe to a sample-collecting system on the apparatus.