Abstract: A disconnect sub for a tubing conveyed perforating gun is shown which includes a tubular member and a sliding mandrel telescopingly received within the interior of the tubular member. A perforating gun is supported by the lower end of the sliding mandrel and the mandrel has an upper colleted end which is initially retained within the tubular member on an internal profile. A retaining sleeve has a lower extent which initially underlies the colleted end of the sliding mandrel within the tubular member. After firing the perforating gun, the sliding mandrel is released by draining an initially filled fluid chamber within the device and by locking the retaining sleeve out of engagement with the colleted end of the mandrel, thereby allowing the mandrel to slide from within the tubular member and fall away within the well bore.

Abstract: A method and apparatus for sealing electrical conductors through a pressure barrier provides high pressure sealing. The apparatus includes a tubular housing with conductor rods which are inserted in the housing, which is then filled with epoxy and allowed to harden. The conductor rods are also insulated. A grommet is press fitted on each end of the housing, by pushing the grommet over installation pins which insert over the conductor rods. A mandrel is used to drive the grommet into compressive contact with the bore of the housing. Once in place, the installation pins are pulled and the mandrel is removed.

Abstract: A cementing apparatus is shown for use with a wireline run setting tool. The apparatus includes a retainer with external gripping and sealing members for sealing off a lower region of the well below the sealing members. The cement retainer has a plurality of cementing ports at the lower end thereof which communicate the interior of the retainer with the lower well region. A sliding valve located within the lower end of the retainer can be moved between open and closed positions to control communication of fluids between the interior of the retainer and the lower well region. An inner body is initially received within the interior of the retainer end is retained in position by means of a collet latch. Actuation of the setting tool sets the gripping and sealing elements of the retainer and moves the inner body to shear the collet latch. This action simultaneously closes the cementing ports by moving the sliding valve within the lower end of the cement retainer.

Abstract: A method of manufacturing a steel bodied bit is shown in which a hardfacing of a highly conformable metal cloth containing hard, wear resistant particles is applied to the bit face as well as to the interior of the bit nozzle openings. By hardfacing the nozzle openings, fluid erosion in the region of the openings is eliminated.

Abstract: Rotary power slips mounted in the rotary table of an earth drilling rig and having slips for gripping and releasing pipe in the rotary table. The air transfer ring has concentric grooves in the upper surface. An annular seal ring is secured to the body of the rotary power slips and has a pair of air passageways. The air passageways lead to secondary fluid conduits in the body, which, in turn, lead to each end of the pneumatic cylinders to raise and lower the slips. Expansive rings are secured to the surface of the air transfer ring by mounting the edges of the rings into the grooves in the air transfer ring. When air pressure is applied through one of the primary fluid conduits, one of the expansive rings expands and cooperates with the lower surface of the seal ring to form an expansive fluid duct. The air pressure flows through a perforation in the expansive ring into the expansive fluid duct, and then through the air passageway and the secondary fluid conduit to the pneumatic cylinders.

Abstract: A tie-back connector for a subsea well allows the tie-back connection to be made without rotation. A set of threads is located on an inner wall of the outer conduit into which the tie-back connection is to be made. An annular latch is carried by the inner conduit which is being tied back from the surface to the outer conduit. The latch has threads on its exterior which ratchet past the threads on the inner wall as the inner conduit is lowered into the outer conduit. After the threads of the latch are ratcheted fully into alignment with the threads in the outer conduit, the inner conduit is pulled upwardly relative to the latch to secure it in tension. A retainer is actuated when the inner conduit is in the upper position to prevent the inner conduit from moving downwardly again relative to the latch. The inner conduit can be removed by rotation relative to the outer conduit.

Abstract: A protection circuit for a power transistor cuts off the transistor if an overcurrent condition occurs. The protection circuit includes control transistors that are switched on and off to alternately supply positive voltage to the base of the power transistor to turn it on and negative voltage to turn it off. A control circuit provides signals to the control transistors to turn them on and off. A latch has an input connected across the collector and emitter of the power transistor for monitoring the voltage. If the voltage exceeds a threshold level at the latch, the latch will provide a disabling output to the control circuit to turn off the power transistor.

Abstract: A downhole motor has a rotor and a stator, of the progressive cavity type, inside a housing. A bearing shaft is mounted within the housing, with a bearing between the housing and the bearing shaft, and the bearing shaft is rotatable about the longitudinal axis of the bearing shaft and the housing. A flexible rod, with a connection on each end, extends between the rotor and the bearing shaft, for translating the rotation and gyration of the rotor to the true rotation of the bearing shaft. A cylindrical overload sub is located concentrically around the rod. A plurality of splines and slots on the connections engage a plurality of splines and slots on the sub to allow the connections to rotate axially a limited amount in relation to one another. Teeth may be used instead of splines and slots.

Abstract: A centrifugal submersible pump has wear resistant features to resist erosion due to sand laden fluid from a well. The pump has diffusers and impellers located within a housing. Wear resistant inserts are secured to the diffusers and impellers. The inserts include inserts with cylindrical surfaces for radial support and sealing, and inserts with flat transverse surfaces for thrust. The inserts are preferably formed of tungsten carbide and are harder than the material of the impellers and the diffusers.

Abstract: A low volume submersible pump assembly has features to stabilize the operation. The pump assembly includes a centrifugal pump driven by a submerged electrical motor. The centrifugal pump has an impeller configuration that is designed for high specific head, but potentially unstable operation. At the design speed, the pump potentially could deliver an indeterminate flow rate for a given head. Also, at the design speed, the design flow rate will yield a design head that is very close to the maximum head at zero flow. The pump has the characteristic of requiring a significant increase in torque to produce higher flow rates. To stabilize the potentially unstable pump, a variable speed drive varies the speed of the motor to maintain constant torque. Maintaining a constant torque allows a considerable variance in head with only a small variance in flow rate resulting.

Abstract: A gear mechanism, of the Moineau type, having an outer gear member with a helical inner surface. The motor also has a helical inner gear member within the outer member. A resilient sleeve is located between the inner and outer gear members, and has helical inner and outer surfaces. The inner gear member has one less helical thread than the inner surface of the resilient sleeve. The outer surface of the resilient sleeve is similar to, but rotationally offset from, the inner surface of the resilient sleeve.

Abstract: A template levelling system includes a pile receptacle carried within the template receptacle mounted to the template. The pile receptacle has a lower flange that extends outwardly from and below the template receptacle. Slips are located in the pile receptacle for gripping the pile to prevent downward movement of the template. A hydraulic jack will grip the pile receptacle and pull the pile receptacle upwardly, causing the flange to contact the lower side of the template to lift the template. The pile receptacle is laterally movable in the template receptacle. A release sleeve can selectively release the slips to allow the pile receptacle to be lowered on the pile.

Abstract: An earth boring bit having a lubrication system that includes a pressure compensator and seals to confine lubricant within the bearings between rotatable cutters and shafts, the seals being of the asymmetrical shear/compression type, each half of which having a load deflection curve resulting from components satisfying the following criteria:D.sub.H >A.sub.p SandD.sub.C >A.sub.p S[(S-1)/S].sup.1/2Where:D.sub.H =Assembly deflection of shaft seal ring with bearing thrust faces in contact (in.);D.sub.C =Assembly deflection of cutter seal ring with bearing thrust faces in contact (in.);A.sub.p =Axial cutter play (in.);S=Ratio seal to cutter movement.Also preferably, D.sub.C .perspectiveto.D.sub.H [(S-1)/S].sup.1/2.

Abstract: A thrust reducing apparatus for a progressing cavity pump used in a well and driven by a submersible pump motor. A piston is mounted to the top of the rotor and located in a bore between the stator and the tubing which extends to the surface. A bypass passage enables fluid discharged from the pump to flow past the bore and the piston. An annulus passage extends into the bore above the piston for communicating fluid pressure in the annulus to the top of the piston. The lower side of the piston is exposed to discharge fluid pressure from the pump, resulting in a net upward force on the piston. The piston pulls upwardly on the rotor to reduce the downward thrust on the rotor.

Abstract: A matrix bit is shown of the type having a metallic mandrel with a connecting end for connection in a well pipe string leading to the well surface. An opposite end is covered with a cast matrix material which defines a central bit body. A plurality of integral blades are formed of the cast matrix material and extend axially and radially from the central bit body. Each of the blades is reinforced by a metallic extension which is contained within the matrix material and extends coaxially with each blade.

Abstract: A top head drive well drilling apparatus having a drive unit for rotating a drill string about the longitudinal axis of the drill string. The drive unit is mounted on a carriage, which is guided along a guide track. A stem extends downward from the drive unit to transmit torque from the drive unit to the drill string. A wrench assembly is mounted on the drive unit for making and breaking connections between the stem and the drill string. The wrench assembly can be moved vertically and horizontally in relation to the stem. A stabbing guide is mounted on the wrench assembly for aligning the stem and the drill string. The stabbing guide can be moved vertically relative to the wrench assembly, and has a gripping head having a pair of pivotal latch arms for closing around the drill string. A trigger and a limit switch automatically close the latch arms around the drill string when the stabbing guide is moved onto the drill string.

Abstract: An earth boring bit having a cantilevered bearing shaft and a compensator system to equalize the pressure of the lubricant with the hydrostatic pressure of the drilling fluid surrounding the bit. A rigid face seal assembly, positioned between the cutter and bearing shaft of the bit, moves axially in response to, and to compensate for, dynamic pressure changes in the lubricant adjacent the seal. The positioning of the seal groove and seal assembly in relation to the bearing surface is such that rigid face seal movement is decreased relative to axial cutter movement during drilling to enhance seal life. Preferably the ratio of rigid ring movement to axial cutter movement is substantially one half to one.

Abstract: A casing hanger seal for a subsea well uses a seal ring having inner and outer walls spaced radially apart from each other. An energizing ring is moved from disengaged position to an engaged position between the walls, wedging them apart to form the metal seal. Vertical slots are formed in the walls to facilitate expansion. The slots ae located in a gripping section that engages wickers formed on the inner and outer tubular members of the well. Circumferential grooves are located in the sealing areas.

Abstract: A method for hardening a selected region of a steel bearing surface of an earth boring bit using the steps of stretching a rubber protector over a seal region to be protected from treatment (the rubber being selected from the group consisting of silicone, neoprene and nitrile), exposing the bearing surface and protector to a medium (selected from the group consisting of carburizing, nitriding, carbonitriding, siliconizing, chromizing and boronizing) of the type for altering the chemical composition of the steel to be hardened, heating the medium and bearing surface, cooling the bearing and protector, and removing and cleaning the surface.

Abstract: A method and apparatus allows dynamic data to be recorded in a drill string for later playback at the surface. The system includes a transducer located in a sub in the drill string which provides electrical responses to a analog to digital converter. A timer circuit provides timer pulses to the converter to cause the response to be converted into a digital value for storing in a recorder. The timer pulses are also used to address the memory location. The timer circuit has the ability to provide a variable number of timer pulses at a variable frequency and at variable intervals. A surface timer circuit provides simultaneous timer pulses to a counter to indicate at the surface which memory location is being filled at any given time.