Abstract: A connector for tying back a riser from a subsea wellhead to a platform, wherein the wellhead has an internal wellhead housing with external grooves thereon. The connector having a plurality of dog members carried within a cavity which engage the external grooves. The dog members are actuated by axial movement of a piston linked to a cam ring. The connector has a plurality of transfer members located within the cavity to support the dog members and transfer upward loading to the wellhead housing during tension on one side due to bending. Further, the connector has a release ring which forces the dog members out of engagement with the external grooves when the connector is released.

Abstract: A hydraulic actuator for a valve that fails as-is in the event of control line failure. The actuator has a housing carrying an actuator piston for actuating the valve open or closed. An elongate gripper shaft extends upward from the actuator piston. A collet member is carried within the housing and adapted to engage the gripper shaft when moved upward relative to the housing. The collet member is biased upward by a spring. A release piston abutting the dog members prevents their upward movement when actuated to a lower position. The release piston is supplied with the same hydraulic fluid pressure as the actuator piston. If pressure is removed, the spring moves the collet member into locking engagement with the shaft.

Abstract: A subsea well has a tubing hanger which has an annulus bore and a production bore. A check valve is located in the annulus bore. A running tool runs the tubing hanger on a monobore riser such as a drill string while holding the check valve in the open position. After setting and testing, the running tool is lifted and a blowout preventer is closed around the landing string. The operator monitors the choke and kill line of the drilling riser, which will be in communication with the check valve. If the check valve is leaking, an annulus plug may be installed in the annulus bore. The installation of the annulus plug may be handled by using a retrieval tool configured to align the annulus bore with the landing string passage. A wireline tool may be lowered through the landing string and retrieval tool to retrieve the check valve and install the plug. Alternately, the check valve may remain in the tubing hanger and the plug is set in the annulus bore above it.

Abstract: A casing annulus remediation system for lowering a flexible hose into an annulus between strings of casing in a petroleum well by pressurizing the hose so that the hose is rigid and may be forced down the annulus. It is necessary to insert the hose through an outlet into the annulus region for well fluid displacement when pressure builds up in the annulus between casing strings due to leaks in the casing. Pressure build-up in the annulus is reduced by pumping a heavy liquid, sealant or other media through the hose into the annular space experiencing the pressure build-up. A tubing nose is affixed to the lower end of the hose. The hose may be inserted hundreds of feet into the well. Therefore, the hose is pressurized to maintain rigidity to keep the hose from winding about the well during deployment. To keep the hose rigid, internal pressure is maintained in the hose. The tubing nose is provided with a check valve that holds the pressure.

Abstract: Drill pipe protection rings for filling external identification slots in drill pipe tool joints prevent damage to the internal seals of a drilling head. The rings are formed from resilient elastomeric materials. In cross-section, each ring has slightly convex inner and outer surfaces, and a series of circumferentially spaced-apart, hemispherical bumps located along its inner surface. One ring is mounted within each slot on each drill pipe section. The rings stretch slightly while being installed, but form a tight fit once they are properly seated. When installed, the outer surfaces of the rings will protrude slightly outward from or beyond the slots. The hemispherical bumps help align and center the rings within the slots. Without the rings, sharp edges of the slots on the drill pipe tool joints could cause severe damage as they passed through the drill head. However, with the rings, the outer surfaces of the slots are substantially filled to prevent their edges from cutting or gouging the elastomers.

Abstract: A dual in-line ball valve assembly for a subsea tree intervention tool has a pair of axially-movable pistons and a rotatable linkage member pinned between each of the pistons and the independently operable ball valves. The linkage members have eccentric hubs which rotate the ball valves between open and closed positions when the pistons are axially actuated. A recess is formed in each ball valve adjacent to the central flow passage of the assembly for accommodating a lower side of tubing or wireline. The recesses prevent shearing of the tubing or wireline in two places when one of the valves moves to the closed position.

Abstract: Two or more opposing and outward facing profiles are fabricated and joined to each other along their outer edges, forming a section of a guide string. The sections of the guide string are secured together in an assembly and lowered into a single conductor. The assembly lands on the bottom of the well and may support its own weight. The guide string defines two separate longitudinal cavities or sections of the well. Each separate cavity allows drilling and installation of casing in the conductor.

Abstract: A subsea wellhead connector has an upper body that abuts the rim of a wellhead member. A hydraulic wellhead connector is carried by the upper body and extends over the wellhead member. The hydraulic wellhead connector carries dogs for moving into an engaged position with a profile on the exterior of the wellhead member. The mating or complementary stepped profile at the top or rim of the wellhead housing is designed to engage at three surfaces. The first surface is the flat surface at the inner diameter. The second surface is the tapered surface at the step. The third surface is the flat surface on the rim from the tapered surface to the outer diameter of the rim. The profiles are dimensioned with bias toward initial contact at the outer diameter flat on the rim of the well housing, second contact is at the inner diameter flat on the rim of the well housing, and the third contact is at the tapered step.

Abstract: A tubular wellhead member has an inner seal surface. A hydraulic passage extends through the wellhead member and terminates at a port at the seal surface. A tubing hanger having an outer mating surface lands in the wellhead member. A hydraulic line extends from a hydraulically operated downhole safety valve to a passage in the tubing hanger and terminates at a tubing hanger port. A seal is located at the tubing hanger port for sealing the junction with the tubular member port. A check valve is located within the seal to maintain the tubing hanger fluid passage closed until the tubing hanger lands in the wellhead. An adapter is employed to apply a running-in hydraulic fluid pressure to the tubing hanger hydraulic fluid passage with the check valve open. Then, the adapter closes the check valve to trap hydraulic fluid pressure in the line leading to the downhole safety valve. This pressure is sufficient to maintain the downhole safety valve in an open position during running in.

Abstract: A caisson wellhead system having a weak point wherein the wellhead system may be installed in a well as a single unit. The caisson wellhead system of the invention includes a lower tubular member having an upper rim. A lower rim of an upper tubular member is placed on the upper end of the lower tubular member. A removable connector is installed inside of and between the lower tubular member and upper tubular member for temporarily connecting the upper tubular member and the lower tubular member. A weak point is formed at the interface between the lower tubular member and the upper tubular member when the removable connector is removed. Therefore, the caisson wellhead system will break at a controlled location if any external components of the well equipment are struck by a foreign object such as an iceberg.

Abstract: An apparatus for performing workover operations on a subsea well that has a subsea production tree with a production passage and an annulus access passageway. The subsea production tree is secured to a lower riser portion. The lower riser portion connects to the tree and has a production passage which registers with a production passage of the tree. The apparatus also has an annulus access passage which registers with the annulus access passage of the tree. The apparatus further includes a monobore riser which extends downward from the surface. A string of tubing, preferably coiled tubing, extends through the monobore riser and defines an inner riser passage and an annular riser passage. A circulation plug is secured proximate a lower end of the coiled tubing and is landed in the lower riser portion of the subsea well. The circulation plug communicates the inner riser passage with the annulus access passage.

Abstract: A flowline connection apparatus having a pivotally mounted funnel an upright frame, which is a permanent part of a subsea well installation such as a manifold or subsea production tree. The funnel rotates is rotatably mounted to rotate from a vertical position to a horizontal position. Retractable pins engage a slot in the funnel to lock the funnel in a vertical position or can be retracted to unlock the funnel, allowing the funnel to rotate to the horizontal position to engage a hub connector. A flowline end termination stabs into the funnel while the funnel is in the vertical position. The flowline termination body has a flange connector on one end that connects to a flexible flowline. The body has an annular external recess for securing the body within the funnel once in place. Pins engage the annular recess to hold the flowline end termination body in the engaged position. A mandrel is carried within an axial bore of the body for axial reciprocal movement.

Abstract: A hydraulic coupling having a lower tubular member and an upper tubular member for sealing engagement one with the other. The lower and upper members are maintained in axial engagement by an axial load. The lower member and the upper member each have an annular body having an axial bore therethrough for the passage of fluid. A metal, concentric inner annular seal leg and outer annular alignment leg extend from the body of the upper member, defining an annular sealing recess between the seal legs. An annular metal sealing portion or wall extends from the body of the lower member and has an inner diameter that defines a sealing surface for insertion into the sealing recess for sealingly engaging the inner annular seal leg. The sealing recess has a backup elastomer ring, which is axially compressed by the sealing portion. When the couplers are made up, the metal-to-metal seal is achieved due to an interference fit between the coupler halves.

Abstract: A subsea wellhead assembly has a tubular housing having a sidewall, an axial bore, and a housing lateral passage extending from the bore through the sidewall. A blocking sleeve fits around the housing to block the housing lateral passage while drilling through the housing. A tubing hanger is secured to a string of tubing and landed in the housing. The tubing hanger has a vertical passage which communicates with the tubing and a tubing lateral passage which extends from the vertical passage and registers with the housing lateral passage. A lower annulus port is in the sidewall of the housing below the lower seal and leads to a tubing annulus. An upper annulus port is in the sidewall of the housing above the upper seal and leads to the bore of the housing. A tree block having a central opening for receiving the housing is lowered over the housing after removal of the blocking sleeve.

Abstract: An adjustable wellhead connector is secured to the lower end of a BOP and riser assembly and has a housing which surrounds a groove profile on the upper outer surface of a first wellhead housing. The housing has a window on its inner surface which contains a removable first locking member. The first locking member has a groove profile on its inner diameter which mates with the groove profile on the first wellhead housing. The first locking member is movable between inner and outer radial positions which correspond to locked and unlocked positions, respectively. The first locking member is moved by a hydraulic system contained within the housing. The wellhead connector may be readily adapted to connect to a second wellhead housing having a different outer diameter than the first wellhead housing by replacing the first locking member with a second locking member. The second locking member enables the wellhead connector to connect a riser to the second wellhead housing.

Abstract: A well production assembly includes a production tree which has a lateral production passage extending laterally from a vertical bore of the tree. A tubing hanger, also having a lateral production passage, lands in the tree, with the lateral passages registering with each other. The junction of the lateral passages has flat, tapered sealed areas which mate with one another. An annulus passage extends vertically through the tubing hanger offset from and parallel to the tubing hanger vertical production passage. The annulus passage also has a lateral passage which registers with the lateral passage formed in the tree. The annulus lateral passages have a flat seal area at their junction. The tubing hanger has a downward facing hydraulic connector which registers with an upward facing hydraulic connector located on a shoulder formed in the bore. Once mated, the connectors provide hydraulic or other auxiliary fluid communication to downhole equipment.

Abstract: A horizontal tree has a vertical bore and a horizontal production passage and is landed in a wellhead housing. A tubing hanger lands in the bore and has a vertical passage and a horizontal passage that aligns with that of the tree. A retrievable first plug seals the vertical passage. A tree cap seals in the tree bore above the tubing hanger and has an axial passage. A retrievable second plug seals the tree cap passage. A vent port extends laterally through the tree cap between its axial passage and outer surface. A pair of seals on the second plug seal above and below the vent port. A tubing annulus passage communicates with the vent port and an annulus passage. The second plug serves as a second pressure barrier to the first plug and blocks the vent port. The annulus passage is sealed from communication with a void between the plugs.

Abstract: An angled passageway is provided in a tubing head of a wellhead assembly for reducing an angle of bend in a control line exiting from a tubing hanger. The angled passageway extends from the bottom to the top of the tubing hanger and is angled relative to the longitudinal axis. By traversing the longitudinal axis with the angled passageway, a sufficient angular orientation of the control line is achieved to minimize bend in the control tube. Another embodiment teaches an upper angled passageway segment in communication with a lower angled passageway segment that interface with one another at an angle. By providing two interacting angled passageways, the required angle of bend of the control tube exiting from the tubing hanger is further reduced.

Abstract: A tensioning device is provided for applying tension to a riser from a surface deck of an offshore oil or gas well. The tensioning device is used with a riser of the type having threads formed on an exterior surface thereof. A tension ring of the tensioning device is formed from first and second ring halves that are clamped together about the riser. The first and second halves have inner threads for engaging the threads of the riser. A clearance exists between the first and second ring halves when the ring halves are clamped together about the riser to allow the first and second ring halves to be tightened against the exterior surface of the riser so that the tension ring is securely fastened to the riser. Fastening means are used for clamping the first and second ring halves together about the riser. Tensioning members that couple at one end to the tension ring and at the other end to the surface deck are used to apply tension to the riser from the surface deck.

Abstract: An undersea telescopic joint for a riser system is connected to a drilling vessel with a plurality of tensioners. The joint has a bearing with inner and outer annular mating members. A cap seals the outer member to the joint. The outer member closely receives and is axially movable relative to the inner member. A flat thrust bearing is located in a chamber between the two members. The members are sealed to one another with upper and lower swivel seals. A passage communicates hydraulic fluid to the chamber. The bearing has a pressure gage which registers with a passage that extends between the swivel seals. The chamber is filled with hydraulic fluid so that the two members are separated and the drilling vessel may rotate easily. The gage is used to detect whether the primary swivel seal is leaking.