Abstract: The present invention provides a latch assembly carriable on a tubing string extendible into a subterranean well, the latch assembly being selectively engageable between upper and lower sections of the tubing string. The latch assembly comprises an outer housing and an inner body, with latching means carried on one of the housing and the body for selectively securing the latch apparatus to the lower section. Latch engaging means are carried on the other of the housing and the body and the lower tubing section for selective co-engagement between the latching means, the lower tubing section, and one of the housing and the body. Piston means are on one of the housing and the body and have a piston head with first and second piston chambers between the piston head.

Abstract: In hanger apparatus of the type comprising a hanger mandrel carried by an inner pipe, an outer body which can be carried by an outer pipe, and a resiliently contractable annular locking device carried by the mandrel for locking the mandrel to the hanger body to suspend the inner pipe, the locking device comprises two independent annular resilient means, the upper one of which constitutes a locking means to cooperate with a locking groove in the hanger body and the lower one of which constitutes a catching means to cooperate with a catching groove in the hanger body below the locking groove. The two annular means are disposed in an outwardly opening annular recess presented by the mandrel. The invention has the advantage that the locking means, which may be a split ring, can be wholly within the mandrel recess as the mandrel is run down to the hanger body, the active outer surfaces of the locking ring thus being protected from being damaged during the trip down to the hanger body.

Abstract: A large diameter duct structure is adapted for vertical disposition in an ocean. An elongate tensile core assembly is adapted to be supported at one end, as from a floating platform, and to extend downwardly a desired distance. A plurality of duct wall sections, each of selected length, are alignable in serial order to define a tubular assembly having a diameter substantially greater than that of the core. Support means are engageable with the core at selected locations along the core and with the wall sections. The support means support the wall section substantially concentrically about the core and secure the wall sections from movement relatively along the core. Seals are engageable between the ends of adjacent wall sections disposed about and along the core, and define substantially liquid-tight connections between the wall sections.

Abstract: A tubing hanger assembly adapted to carry a tubing string suspended therefrom and to be connected to a landing tool for lowering of the tubing hanger assembly and tubing string into a well casing means, and landing said tubing hanger assembly on said casing means and simultaneously locking said assembly to said casing means without relative rotation of said landing tool and tubing hanger assembly. A tubing hanger assembly adapted to be releasably connected to a landing tool under conditions where the weight of the landing string is imposed upon the tubing hanger assembly whereby the connection between the landing tool and the tubing hanger assembly is releasable by relative rotation of the landing tool with respect to the tubing hanger assembly in one direction only.

Abstract: In hanger apparatus of the type comprising a hanger mandrel carried by an inner pipe, an outer body which can be carried by an outer pipe, and a resilient locking ring carried by the mandrel for connecting the mandrel to the hanger body to suspend the inner pipe the locking ring is in the form of an integral piece comprising a body portion, which cooperates with the hanger body to support the mandrel, and a dependent skirt which carries an inturned bottom flange cooperating with a retaining groove on the mandrel.

Abstract: An improved hanger apparatus for suspending an inner pipe from an outer pipe or other annular member. The invention applies to hanger apparatus of the type comprising a hanger mandrel carried by an inner pipe, an outer hanger body, which can be carried by an outer pipe, and a resilient locking ring carried by the mandrel for connecting the mandrel to the hanger body to suspend the inner pipe. Hanger apparatus according to the invention have both special catch surfaces, coacting between the mandrel and outer hanger body to assure that full engagement occurs as a result of lowering the mandrel into the hanger body, and special load bearing surfaces for transferring the load to the outer hanger body when engagement has been achieved.

Abstract: A well casing hanger for suspending an inner string of well casing at a predetermined location in an outer casing string, including a pair of semi-circular segments each having a plurality of outwardly biased latching fingers extending upwardly from an externally threaded semi-circular support base. An internally threaded connecting ring is threaded onto external screw threads on the casing string and onto the semi-circular support bases which are positioned around the hanger body to secure the segments on the string until the inner casing string is positioned accurately. The weight of the inner casing string shears the connecting ring to permit the latching fingers to be releasably locked in an outwardly urged latched position.

Abstract: A sub for use in an acoustic telemetry system provides a sound path of low impedance to facilitate the transmission of acoustic signals through a string of pipe positioned in a wellbore. The sub section of pipe includes a tubular receiving member positioned in the bore of a pipe section and spaced from the interior walls thereof. Ports and flow channels are also provided to permit the passage of well fluids through the pipe section when an acoustic instrument is positioned in the tubular receiving member. A lateral shoulder is formed in the interior wall of the receiving member and is arranged to matingly receive a flat portion on the instrument. The abutment of the flat portion of the instrument and the shoulder provides a positive sound path for transmission of longitudinal sound waves from the instrument to the receiver member.

Abstract: A tubular member is provided with seals thereon for sealing in a liner receptacle supported in a well string in a well bore. Expandable seal means are provided on the tubular member with actuating means for expanding the expandable members into engagement with the well string above the receptacle, and releasable retaining means engage the actuating means with the tubular member to retain the actuating means in a non activated position until the releasable retaining means are actuated. Additional means secure the actuating means on the tubular member to inhibit premature release of the releasable retaining means as the seal nipple packer is lowered through the well string to be positioned in the receptacle. Slip segments are releasably connected to an expander cone, with both being mounted on the tubular member in longitudinal spaced relation to the actuating means at the other end of the expandable seal means.

Abstract: A hanger for supporting dual tubing strings in a well casing from hanger mandrels which can swivel to facilitate threadedly connecting each mandrel to its associated tubing string. The hanger includes an orienting sleeve for receiving safety shut-off valves, the sleeve being adapted to swivel with respect to the rest of the hanger, making it easier to assemble the hanger onto the running and setting tool used for setting the hanger in the casing.

Abstract: Apparatus is provided for running, setting and anchoring a liner in a well bore casing, comprising inner and outer bodies with expander and gripping means carried on the bodies to provide means for gripping engagement with casing. A running tool is secured to the bodies and defines drag means thereon to resist longitudinal travel while the apparatus is being mechanically set. A piston element is carried on the running tool and is responsive to fluid pressure entrappable in a piston pressure chamber to hydraulically set the hanger. Mechanical setting means are provided and may be activated to set the hanger upon failure of the hydraulic activation means.

Abstract: The described invention includes method and apparatus for the installation of a casing hanger supporting a string of casing down hole in an oil or gas well, for removal of the installation equipment, and for tying back the hanger to an insulated production riser extending to the surface. The casing hanger is lowered into the well on drilling casing, having a smaller outside diameter than the insulated production riser casing, to permit a sufficiently large annulus for the passage of fluid between the drilling riser and the previously installed drilling riser. The drilling riser is removed by disconnecting it from the hanger by clockwise rotation of the drilling riser. The insulated production riser casing, or other special riser pipe, having a larger outside diameter than the drilling riser casing, is used to tie back with the hanger where standard riser casing is not suitable for the production of oil or gas, e.g. in the case of production through permafrost, by a clockwise rotation of the drilling riser.

Abstract: Well completion apparatus for disposition in a well conduit comprising first and second seal assemblies. The first seal assembly comprises a first cylindrical receptacle member fixed with respect to the well conduit and a first insert member including a first tubular body portion received within the first receptacle member. One of the first members includes a first annular seal coaxial with and sealingly engaged between the first receptacle member and the first tubular body portion. The second seal assembly comprises a second cylindrical receptacle member rigidly adjoining the first tubular body portion and a second insert member including a second tubular body portion received within the second receptacle member. One of the second members includes a second annular seal means coaxial with and sealingly engaged between the second receptacle member and the second tubular body portion.

Abstract: A tubing hanger for suspending multiple strings of tubing in a subsea wellhead or casing hanger upon being lowered from the drill vessel into a properly oriented seating position in the casing hanger. The tubing hanger is releasably secured to the casing hanger by hydraulic manipulation of the running tool after the tubing hanger has been oriented in the casing hanger. Thereafter, by further hydraulic manipulation, the running tool is released from the hydraulic set tubing hanger for retrieval to the drill ship. The running tool may later be returned and connected to the tubing hanger and, by further manipulation of the running tool, the hanger is disconnected from the casing hanger and elevated to the drill ship.

Abstract: A well tool for running and landing underwater casing hangers. The tool includes a resilient split ring with external threads that engage complementary internal threads on the hanger, and an hydraulic system that is actuated through a control line at the surface, thereby facilitating release of the hanger from the tool by either hydraulic pressure or rotation of the running string to which the tool is attached.

Abstract: An apparatus and method are provided for running, setting and anchoring a liner in a well bore casing, said apparatus being connectable to a tubular member extendible to the top of the well. The apparatus comprises an inner longitudinally extending body with an outer longitudinally extending body being around the inner body. Connection means on one of said inner and outer bodies are provided for connection of a liner extending below the apparatus. Expander means are carried on one of the inner and outer bodies, with gripping means being carried on the other of the inner and outer bodies. The gripping means are engagable with the expander means such that the gripping means are shifted into gripping engagement with the casing. A manipulatable tubular running tool is releasably secured to the inner and outer bodies.

Abstract: A dual marine riser for use in drilling deepwater oil and gas wells from a floating vessel, the marine riser incorporating concentric inner and outer risers, the outer riser being provided with one or more remotely-actuatable valves adapted to bring the annular space between the risers into communication with surrounding sea water in order to equalize pressures over the wall of the outer riser when the inner riser has been installed.

Abstract: Precompletion apparatus for use in air drilling and casing a problem formation in a well including a casing landing nipple at the lower end of a first string of solid well casing installed by suitable conventional techniques, an expendable plug for engagement in the casing landing nipple to plug a well bore after air drilling below the casing landing nipple to control the well during inserting of a slotted liner, an expending shoe for engaging and displacing the plug downwardly from the landing nipple, a slotted well bore casing for lining a well bore along a problem formation which has been air drilled, and a casing hanger for supporting the slotted liner along the air drilled portion of the well bore from the landing nipple. The plug and hanger each have locking keys engageable with a casing landing nipple and expandable seals for sealing with a seal surface along the casing landing nipple.

Abstract: The described invention includes method and apparatus for the installation of a casing hanger supporting a string of casing down hole in an oil or gas well, for removal of the installation equipment, and for tying back the hanger to an insulated production riser extending to the surface. The casing hanger is lowered into the well on drilling casing, having a smaller outside diameter than the insulated production riser casing, to permit a sufficiently large annulus for the passage of fluid between the drilling riser and the previously installed drilling riser. The drilling riser is removed by disconnecting it from the hanger by clockwise rotation of the drilling riser. The insulated production riser casing, or other special riser pipe, having a larger outside diameter than the drilling riser casing, is used to tie back with the hanger where standard riser casing is not suitable for the production of oil or gas, e.g. in the case of production through permafrost, by a clockwise rotation of the drilling riser.

Abstract: Disclosed is a swivel assembly with multiple fluid bearings. The embodiment shown is a rotatable liner swivel assembly to be used, in conjunction with a liner hanger, cam dog assembly, and setting tool, for placing and cementing a liner in a well. Fluid-filled annular bearing chambers in the swivel assembly support the load of the liner pipe string, and permit the rotation of the liner pipe string with respect to the liner hanger during the cementing process. The bearing chambers are interconnected to equalize the fluid pressure and distribute the load uniformly over the bearing chambers.

Abstract: An apparatus and method for running a compression-type annulus packoff on a drill or other pipe string into an oil or gas well, setting the packoff without rotating the drill string, and then shifting the axial load of the drill string from the packoff to a casing hanger or other suitable well element so that the packoff can be pressure tested under conditions closely simulating normal service conditions. The apparatus comprises an hydraulically actuated well tool that functions both as a means for connecting the packoff to the drill string on which the tool and packoff are run as an assembly into the well, and also as a means for converting hydraulic pressure in the drill string into torque and then transmitting this torque to the packoff for rotating its seal-compressing element, thereby compressing its seal into fluid-tight engagement with the adjacent well elements.

Abstract: A liner hanger assembly and method of installation for use in oil and gas well operations having multiple individual hanger units arranged in series for even load distribution. Each individual hanger unit carries a proportional amount of the weight load of a suspended well pipe (casing liner) and has a balanced pressure, sealed bearing which facilitates rotation of the casing liner in the well bore during cementing operations.

Abstract: Precompletion apparatus for use in air drilling and casing a problem formation in a well including a casing landing nipple at the lower end of a first string of solid well casing installed by suitable conventional techniques, an expendable plug for engagement in the casing landing nipple to plug a well bore after air drilling below the casing landing nipple to control the well during inserting of a slotted liner, an expending shoe for engaging and displacing the plug downwardly from the landing nipple, a slotted well bore casing for lining a well bore along a problem formation which has been air drilled, and a casing hanger for supporting the slotted liner along the air drilled portion of the well bore from the landing nipple. The plug and hanger each have locking keys engagable with a casing landing nipple and expandable seals for sealing with a seal surface along the casing landing nipple.

Abstract: Apparatus and method for cementing a liner in a well bore in which the apparatus may comprise: a setting tool having a tubular mandrel connected in a pipe string for extension through the liner; a liner wiper releasably disposed within the liner near one end of the mandrel; a plug member for effecting a movable seal behind cement as it is pumped through the pipe string into the liner; a seal assembly sealingly engaging the exterior of the mandrel and the interior of the liner above the liner wiper; and a latch assembly releasably connecting the seal assembly to the liner so as to permit limited axial movement of the mandrel without disturbing the axial position of the seal assembly. In the method of cementing a liner using the apparatus, the force due to pressure applied to the seal assembly, during pumping of cement, is transferred to the liner without transfer to the mandrel.

Abstract: Running apparatus is releasably connected to a packing assembly, the combination being lowered on a tubular running string until the packing assembly is disposed between a hanger body and a surrounding wellhead underlying a body of water. The apparatus is responsive to weight to effect setting of the packing in the annular space between the hanger body and wellhead. Test pressure is applied to the packing and more firmly sets it. The apparatus is rotated relative to the packing to shift a locking nut to lock the packing in place, the apparatus then being retrieved to the drilling rig at the water surface.