Abstract: Methods and devices for restoring control of at an offshore oil well following an uncontrolled fluid release after an explosion include lowering through a riser of successive flow restricting inserts into the oil well to gradually reduce the uncontrolled fluid release. Flow restricting inserts may be inserted in parallel or in series with each other. Following attachment of the riser to the oil well, provisions are made to restore oil production from the well. Flow restricting inserts may further be used to adjust flow resistance from the well in order to optimize oil production. Passages between the riser and the flow restricting inserts may also be used to form a gas lift in order to maximize production of oil from the well.

Abstract: A blowout preventer assembly comprising a blowout preventer and control apparatus, the blowout preventer comprising a housing a sealing element and a fluid pressure operated actuator mounted in the housing, the actuator 18 dividing the interior of the housing into two chambers, namely an open chamber and a close chamber, substantially preventing flow of fluid between the two chambers, and being movable, by means of the supply of pressurised fluid to the close chamber, to urge the sealing element into sealing engagement with a drill pipe extending through the blow out preventer, the control apparatus including a close line which extends from the exterior of the housing to the close chamber, and a source of pressurised fluid which is connected to the close line, wherein the source of pressurised fluid is located adjacent to the housing.

Abstract: Systems and methods for the prevention or dissolution of hydrates in an undersea well. One example system includes a submersible isolation bell for capturing effluent being exhausted from the well, and an umbilical. A power cable supplies electric power to the submersible isolation bell, for example for heating of the interior of the submersible isolation bell to prevent or discourage the formation of methane hydrates and the precipitation of other byproducts. Diluents may be supplied to the submersible isolation bell to further discourage the formation of hydrates and precipitation of other byproducts. The diluents may be heated locally at the submersible isolation bell, using electric power supplied by the power cable. A conformable seal may substantially seal the submersible isolation bell to a riser or other structure at the wellhead.

Abstract: A two phase gas-liquid separation apparatus is provided that shapes the flow in a flow shaping line. Shaping the two-phase flow allows centrifugal force to send the heavier, denser liquid to the outside wall of the flow shaping line and allows the lighter, less dense vapor or gas to occupy the inner wall of the flow shaping line. With the gas positioned on the inner wall of the flow shaping line, an exit port on the inner wall will allow for the majority, if not all, of the gas, along with a low amount of liquid, to be sent to a conventional separator. A high ratio of vapor/liquid at a flow rate much lower than the total flow rate within the flow shaping line is sent to the conventional separator. This allows for efficient separation of the vapor from the liquid with the use of a smaller conventional separator.

Abstract: A method of separating a tubular element, comprising providing a tubular element having an inner and an outer surface, a circumference of said outer surface, and a first end and a second end; radially surrounding said tubular element with an explosive material, wherein said explosive material is capable of generating a high-velocity plasma jet in response to an activation signal, and wherein said explosive material comprises an electrically conductive layer; transmitting said activation signal to said explosive material; generating said high-velocity plasma jet; and separating said tubular element into a first portion comprising said first end and a second portion comprising said second end when said high-velocity plasma jet penetrates said outer surface of said tubular element and exits said inner surface of said tubular element.

Abstract: A method and apparatus for forming an elongate tubular from a composite material. The composite material includes fibers and epoxy resin that are disposed around an elongated mandrel. The fibers are wound around the outer circumference of the mandrel and the epoxy resin may be applied to the fibers, before, during, or after, being wound onto the mandrel. A trough is provided that supports the mandrel between ends of the mandrel. An example trough includes a flexible membrane supported on its lateral ends to resemble a catenary.

Abstract: There is provided a high power shear laser module, which can be readily included in a blowout preventer stack. The shear laser module as the capability of delivering high power laser energy to a tubular within a blowout preventer cavity, cutting the tubular and thus reducing the likelihood that the tubular will inhibit the ability of the blowout preventer to seal off a well.

Abstract: Methods and systems for drilling subsea wells bores with dual-gradient mud systems include drilling the subsea well bore while employing a subsea pumping system, a subsea choke manifold and one or more mud return risers to implement the dual gradient mud system. When a well bore influx is detected, the well bore is shut in, and components determine if pressure control may be used to circulate the influx out of the well bore, the size of the influx, and how much the mud system weight will need to be reduced to match the dual gradient hydrostatic head before the influx reaches the subsea pump take point. The subsea pumping system, subsea choke manifold, and mud risers are isolated while the influx is circulated up one or more fluid passages in the drilling riser package using the surface pump, through the wellhead, and out the surface choke manifold.

Abstract: Methods and systems for a backup emergency disconnect signal (EDS) transmission in an offshore oil and gas installation are provided. A backup EDS transmission system includes a pressure pulse generator located close to a water surface and configured to generate a predetermined pressure variation pattern including at least one of positive and negative pressure pulses and corresponding to an emergency disconnect signal, the signal being propagated downwards in a mud column. The pressure pulse generator is located at a surface end of the mud column. The backup EDS transmission system also includes a pressure pulse receptor connected to a controller of blowout preventers and configured to measure a pressure in the mud column, at a subsea location.

Abstract: A connector is lowered onto and secured to a subsea member, effecting a seal between subsea member and the connector. The connector includes an outer body defining a cavity, and an inner body defining a bore, wherein the lower end of the inner body resides within the cavity. The connector also includes an engaging member coupled to the outer body and adapted to engage the subsea device, the engaging member radially movable between a disengaged position and an engaged position. The connector includes a seal carried by the inner body and adapted to form a seal between the bore and the subsea device. Finally, the connector includes a pre-loading member coupled to the outer body, operable to urge the inner body and seal against the subsea device to exert a pre-loading force on the seal. A differential pressure between the bore and a subsea environment energizes the seal.

Abstract: Subsea power sources and related systems include a housing having at least one first magnetic member, an internal member having at least one second magnetic member, and at least one elastic member positioned in the housing. Movement of the one or more second magnetic members relative to the one or more first magnetic members, which can be obtained by positioning the power source in a subsea environment such that forces therein contact and move the housing or internal member, produces an electromagnetic output for powering a subsea object. Contact between the internal member and one or more elastic members causes the one or more elastic members to impart a force to the internal member to facilitate continued movement and power generation. Power generated in this manner or through other means is usable to operate a subsea kill plant, usable to kill a well or operate a subsea blowout preventer.

Abstract: A hydraulic control system for operating a subsea blowout preventer includes a surface manifold configured to convey hydraulic power to the blowout preventer, a surface actuation valve hydraulically connected to subsea valves and configured to operate the blowout preventer, and a control system monitoring apparatus. The control system monitoring apparatus includes a surface manifold pressure transducer hydraulically connected to the surface manifold, an electronic readback system, and a surface control line pressure transducer hydraulically connected to the surface end of at least one control hose and the surface actuation valve. The control system monitoring apparatus is configured to read, record, and process pressure data supplied by the surface manifold and surface control line pressure transducers.

Abstract: An apparatus which includes a housing defining a chamber, the chamber being sealed from an exterior of the housing, wherein the housing further defines an opening in fluid communication with the chamber and the exterior of the housing. The apparatus further includes a valve in fluid communication with the opening and positioned between the chamber and the exterior of the housing and a member at least partially positioned within the chamber and moveable relative to the housing such that opening of the valve allows fluid to enter the chamber from the exterior of the housing and move the member. A method to operate the same is provided.

Abstract: A method for pressurizing a hydraulic accumulator includes creating an annulus pressure zone in hydraulic communication with the hydraulic accumulator through a hydraulic recharging circuit and applying a hydraulic pressure to the annulus pressure zone. Operating the hydraulic recharging circuit in response to applying the hydraulic pressure and pressurizing the hydraulic accumulator in response to operating the hydraulic recharging circuit.

Abstract: A pressure tolerant battery that may be utilized in a subsea riser includes one or more lithium polymer cells enclosed in a pressure compensated housing. The pressure tolerant battery can be mounted on a landing string a disposed in the riser annulus to provide electrical power to landing string and subsea well system devices.

Abstract: Certain aspects and embodiments of the present invention are directed to a subsurface safety valve disposed in a wellbore through a fluid-producing formation. The subsurface safety valve can include a closure mechanism. In some embodiments, the subsurface safety valve can be coupled with an electric submersible pump. The subsurface safety valve coupled to the electric submersible pump can be positioned in a passageway defined by a tubing string via a power cable coupled to the electric submersible pump. In some embodiments, the subsurface safety valve can include at least one terminal. The at least one terminal can form an electrical connection between the subsurface safety valve and the electric submersible pump. The subsurface safety valve can receive power from the electric submersible pump via the electrical connection.

Abstract: A fluid control device is provided for controlling and/or halting an uncontrolled flow of petroleum or natural gas from an open well head on the sea floor. The fluid control device includes an elongated member having a diameter smaller than the inside diameter of the well head casing. A tapered section in connection with the elongated section, has a diameter equal to or greater than the inside diameter of the well head casing. An end section connected to the tapered section has a diameter greater than or equal to the outside diameter of the well head casing. The fluid control device, under its own mass or under an external force, overcomes the upward forces created by the flowing petroleum or natural gas, resulting in sufficient downward movement of the fluid control device and contact with the open well to seal the well head casing or drill pipe.

Abstract: A method and an apparatus for killing of uncontrolled oil fountain include a series of rods with the first rod having the smallest diameter and successive rods having increasing diameters. Such telescopic assembly of rods is lowered into the well to cause gradual reduction in cross-sectional area available for oil flow discharge. Once sufficiently large rods are lowered into the well, the oil fountain discharge will be greatly diminished. Final sealing may be accomplished by pumping cement into a space formed between the well pipe and the rod assembly. A novel system for aligning the rods to the center of the well is also described.

Abstract: Systems and methods supplementing existing management methods to corroborate performance of a blow out preventer for a submerged well. The corroborator is located on the blow out preventer and includes a flow meter external to a pipe to measure flow inside the pipe, a pipe joint locator, a ram seal confirmation agent and a dedicated communication connection from the corroborator to a computer topside. Data from at least one sensor topside, which may represent a mud tank level, is also received. The computer calculates a probability that a malfunction related to the well occurs. The computer implements a Principal Component Analysis model of the well based on historical data, to assess a likelihood that a threshold value will be surpassed based on collected sensor data and to generate an alert.

Abstract: In-riser power generation devices and methods are utilized to generate power subsea to operate subsea devices of a subsea well system. A turbine power generator is located in fluid communication with a subsea fluid flow path of a subsea well system and the turbine power generator is operationally connected to a subsea power device.

Abstract: A device comprising a sleeve in the form of a cylinder to be placed over a defective deep-water subsea oil-well equipment structure such as a defective Blow-Out Preventor (BOP), said cylinder being anchored by suction anchors and including a roof in the form of a funnel and including pipelines for introducing methanol for preventing hydrates formation and pipelines for removing water/oil/methanol mixture, where the space between the inner wall of the cylinder and the outer surface of the sub-sea equipment may be filled with grout, is suitable for stopping run-away oil-well leakage. A process for stopping run-away oil-well leakage by using said structure is also disclosed.

Abstract: The present invention regards a device designed for injection of fluids in a well bore, typically an offshore well bore for petroleum production and gas injection/gas lift system for fluid injection. The device comprises a outer hollow housing (1) with an internal body (2) moveable within the outer housing (1) with an internal bore(3) which in a first closed position is closed with a metal to metal seal system between the outer housing (1) and the internal body (2), which internal body (2) is operated by pressure differential across the internal body (2), where the internal body (2) is designed with slots (4) forming outlets of the internal bore (3) which in an open position of the device is positioned outside of the outer housing (1).

Abstract: A method for killing an uncontrolled fountain in an oil well following a blowout includes a serial lowering into the well of narrow flow restricting rods, each rod being sufficiently small in diameter to allow its insertion against a high well pressure urging the rods out of the well. Each subsequent rod reduces the cross-sectional area of the well and gradually reduces the flow of fluid discharge out of the well. Once the fountain is sufficiently reduced, the well may be killed using traditional sealing techniques such as pumping cement down the well.

Abstract: The invention provides a drilling system for drilling subsea wells from a floating mobile offshore drilling unit (MODU), the system comprising a subsea BOP. The system is distinctive in that the subsea BOP has relative small weight and size, the system includes no marine riser but the system comprises: flexible choke and kill lines arranged between the subsea BOP and the MODU, means for drill string guidance and cleaning, for guiding when inserting or taking out a drill string from the BOP and for drill string cleaning when pulling the drill string out from the BOP, means for controlled leakage of seawater into a recovery funnel arranged below the means for drill string cleaning but above the BOP, and means for return from the recovery funnel to the MODU of drilling fluid and seawater leaked into the recovery funnel.

Abstract: A subsea safety system (50) for use during a well treatment operation. The subsea safety system (50) includes a tubular string having an inner flow passage (112). At least one valve assembly (116, 134) is positioned within the tubular string. The valve assembly (116, 134) is operable between open and closed positioned to selectively permit and prevent fluid flow therethrough. A frangible liner (134) is disposed within the valve assembly (116, 134). The frangible liner (134) has a close fitting but not fluid tight relationship with the valve assembly (116, 134). The frangible liner (134) is operable to protect the valve assembly (116, 134) from particle flow during the well treatment operation. In addition, the frangible liner (134) is operable to shatter responsive to closure of the valve assembly (116, 134), thereby allowing full operation of the valve assembly (116, 134).

Abstract: A wellhead safety device can include a tubular with outer surface portions having different diameters. A first seal groove can be disposed on a first outer diameter. A locking groove can be formed in a first outer surface portion, and can have sloping sides that taper to a center for receiving locking pins of a tubing head. A sloping guide can extend from a first end towards a central bore of the wellhead safety device. A second seal groove can be disposed on a second outer surface portion for containing a second seal. A guide shoulder can be formed on a second end, and can taper from the second outer surface portion to the central bore. A J-latch can be formed in the first end. A landing shoulder can stop the wellhead safety device from slipping into wellbores.

Abstract: A system for drilling and/or producing a subsea wellbore comprises a primary BOP comprising a primary ram BOP. In addition, the system comprises a secondary BOP releasably connected to the primary BOP, the secondary BOP comprising a secondary ram BOP. The primary rain BOP is actuatable by a first control signal. The secondary ram BOP is actuatable by a second control signal. The secondary rain BOP is not actuatable by the first control signal.

Abstract: The invention relates to oil-and-gas industry and can be used in emergency killing of wells. The method of emergency killing of a well of underwater head position comprises a cementing composition squeezing, wherein depth of the well section to be cemented is defined basing on the well condition and pressure in it, an injector, fixed on the tank with cementing composition and placed inside a bag made of some flexible material, is bottomed and inserted into the wellhead, the bag being filled with cementing composition which is squeezed into the bag through the injector from the tank, and providing for a firm contact of outer surface of the bag with inner surface of the well, the injector being kept at a target depth by means of the weight of the whole structure filled with the cementing composition, pressure in the bag being maintained till the cementing composition hardening.

Abstract: A stabilization device is for a wellhead wherein an upper portion of a wellhead casing extends up above a seabed, the upper wellhead casing portion being sideways supported in a suction substructure. A blowout preventer extending up from the upper portion of the wellhead casing is provided with multiple supporting elements abutting supportingly an edge portion of an end cover on the suction substructure. A method is for stabilizing a wellhead wherein an upper portion of a wellhead casing extends up above a seabed and is sideways supported in a suction substructure surrounding the wellhead casing portion and extends downward in an uncompacted material.

Abstract: Several, preferably three, deflection elements are placed and fixed around the wellhead, preferably in equal circumferential distances around the wellhead. For each deflection element a guiding cable is lowered with its head end from one or several, preferably three workspaces in the direction of the wellhead. Each guiding cable is looped with its head end through the corresponding deflection element, wherein each deflection element forms a point of reversal. Each guiding cable is pulled back with its head end side to the corresponding workspace while in return additional guiding cable is supplied and passed through the corresponding deflection element. A sealing element which is fastened to each guiding cable is lowered in the direction of the wellhead by pulling the guiding cables at their head end sides upwards and, in return, supplying the guiding cables in the direction of the wellhead on the lowering side.

Abstract: An embodiment of a method for limiting the probability of failure on demand of a subsea test tree (“SSTT”) includes the steps of providing a safety shut-in system for actuating a safety valve of the SSTT, the safety shut-in system including a surface control station positioned above a water surface connected via an umbilical to a subsea control system positioned below the water surface to actuate the safety valve; and diagnostically testing the safety shut-in system without actuating the safety valve.

Abstract: An apparatus and method for the creation of an impermeable pile in the vicinity of a dysfunctional oil well are provided. The impermeable pile is sealed and impervious to sea water and of sufficient strength to sustain the oil pressure to prevent oil leakage into the sea. The impermeable pile is configured for receiving oil from the well and discharging oil through a pipe leading to the surface.

Abstract: Method and deadman test circuit for testing a functionality of a shearing blowout preventer. The circuit includes a solenoid valve configured to be electrically controlled and to receive a fluid under a first pressure; a sub plate mounted valve configured to be hydraulically controlled by the solenoid valve and to receive the fluid under a second pressure; and a selector valve fluidly connecting an output of the sub plate mounted valve to a shearing blowout preventer and to a device. The selector valve is configured to be operated by an operator.

Abstract: System and method for controlling a blowout preventer (BOP) stack and a tree attached to a wellhead of a well. The system includes at least a MUX pod configured to receive electrical signals and a fluid under pressure, and to provide a first set of functions to the LMRP part, and a second set of functions to a lower BOP part; a pod extension module configured to receive the fluid under pressure from the MUX pod, and to provide a third set of functions to the tree based on the received fluid under pressure; and a control part configured to be attached to the tree and to communicate with the pod extension module. The third set of functions for the tree is different from the second set of functions provided to the lower BOP part.

Abstract: The method of providing increased motive force for one or more rams of a subsea blowout preventer comprising providing a one or more pistons connected to the one or more ram, the pistons having a distal side and a proximate side with respect to the ram, providing a tank contain a first pressure less than the ambient pressure of seawater at the location of the subsea blowout preventer, and communicating the first pressure with the proximate side of the one or more pistons to cause or enhance the differential pressure across the one or more pistons to urge the rams toward the center of the bore of the subsea blowout preventer.

Abstract: The invention provides a method and system for accessing a well to subterranean formations in which a first well control assembly is directly associated with the well and a second well control assembly is remotely and capable of being in fluid communication with the well.

Abstract: A BOP stack encapsulation system has dual partially hemispherical dome sections which are each supported and guided for linear movement to open and closed positions relative to base plate. The dual containment domes are moved from open positions to closed and hermetically sealed positions about a BOP stack responsive to sensing BOP leakage or a dangerous pressure condition and are controllable from a remote location. When both containment domes are closed they develop concentrically arranged dual hermetically sealed spaces that enclose the BOP stack and capture any leaked fluid and pressure. Captured well fluid constituents can be bled from the internal spaces of the concentric encapsulation domes as desired.

Abstract: A valve system for ensuring well closure upon exposure to a predetermined condition even where a well access line is disposed through the valve. This system may be configured with a supplemental power supply capable of effectuating a cutting closure of the valve. Thus, any obstructing well access line such as coiled tubing may be cut during closure to ensure sealing off of the well, even if the cutting mechanism is separated from its traditional power supply by shear or parting of a portion of the landing string. Once more, the supplemental power sufficient for a cutting closure is only provided in the event of a predetermined condition such as the emergence of a potentially hazardous tubular separation.

Abstract: The present invention relates to blocking a flow of crude oil or natural gas from a steel pipe for extracting the oil or the like that has been installed in the sea when the steel pipe is broken. When a steel pipe 4 for petroleum well in the deep sea is broken, a carrying pipe 6 is inserted from a hole 5 that is a broken point in the steel pipe 4 to a predetermined depth and is fixed. The carrying pipe 6 is an elongated pipe made of nonmagnetic material such as synthetic resin. The carrying pipe 6 has a diameter that is approximately one-half the diameter of the steel pipe 4. A circular mesh plate 8 is hung at a tip portion of the carrying pipe 6.

Abstract: A method for controlling hydrocarbons flowing from a subsea structure comprises lowering an adapter from the surface to a subsea structure. The adapter has a through bore extending between an upper connector having a first connector profile and a lower connector having a second connector profile that is different than the first connector profile. In addition, the method comprises coupling the lower connector of the adapter to the subsea structure. Further, the method comprises lowering a containment cap from the surface to the adapter. Still further, the method comprises coupling the containment cap to the upper connector of the adapter.

Abstract: A diverter system for a subsea well has a blowout preventer and a diverter affixed to an outlet of the blowout preventer. The blowout preventer will have an interior passageway with an inlet at a bottom thereof and an outlet at a top thereof. The diverter has a flow passageway extending therethrough and communication with the interior passageway of the blowout preventer. The diverter has a valve therein for changing a flow rate of a fluid flowing through the flow passageway. The diverter has at least one channel opening in valved relation to the flow passageway so as to allow the fluid from the flow passageway to pass outwardly of the diverter. At least one flow line is in valved communication with the flow passageway so as to allow fluids or materials to be introduced into the flow passageway.

Abstract: A modular containment cap for containing a subsea wellbore discharging hydrocarbons comprises a lower assembly including a spool body having an upper end, a lower end opposite the upper end, and a first throughbore extending from the upper end to the lower end. In addition the containment cap comprises an upper assembly including a spool piece having an upper end, a lower end opposite the upper end, a throughbore extending from the upper end to the lower end, and a first spool piece valve disposed in the throughbore. The first spool piece valve is configured to control the flow of fluids through the throughbore of the spool piece. The upper end of the spool body is releasably connected to the lower end of the spool piece, and the first throughbore of the spool body is coaxially aligned with and in fluid communication with the throughbore of the spool piece.

Abstract: A subsea connection device for connecting to an existing subsea joint comprises a body having a central axis, a first end, a second end opposite the first end, and a throughbore extending axially from the first end to the second end. The first end comprises a connector configured to couple the body to a capping stack. In addition, the device comprises a seal element mounted in the throughbore at the second end of the body. Further, the device comprises a latching assembly disposed about the second end of the body. The latching assembly includes a base coupled to the body and a plurality of circumferentially spaced latching members pivotally coupled to the base.

Abstract: A deepwater blow out throttling apparatus and method. The apparatus is sized to reach an equilibrium between the force of the oil flow against the equipment that constitute the apparatus during its assembly and the forces available from the ROV and the drill ship and connexion pipe to hold the pieces in position for assembly. This solution is applicable to all wells and requires sizing the diffusion transition spool and the throttling valves such that the forces of the flow of the free discharging oil can be overcome by the forces available from the ROV and drill ship. Downward loading from the drill ship during the throttling is applied as throttling generates forces and vibration that can exceed the physical strength of the riser piping and connections. Slow closing of the throttling device must be assured to avoid shocking (or water hammering) the oil well installation.

Abstract: Oceanic petroleum oil wells, though evolving over decades in technology, catastrophic events with mortality and morbidity, and damage to the aquatic and terrestrial ecosystem are still threats to any ventures in this intriguing avenue. The present embodiments of inventions are directed to emergency measures to weather through adversities of some commonly encountered situations. They further include temporary and permanent reparative measures aiming at salvaging the oil well, whose work and economic involvements are far from normal dimensions. The novelty, simplicity, and workability in situations when none such consolations exist, the instant inventions are worthy of a try by all measures. The author inventor, also has to invent a suitable aphorism, to write along with: ‘When there is a thunder storm, rain or hail, a mansion may await . . . yet a shelter had to be found, even if a doll house.

Abstract: A device for relieving pressure in a subsea component comprises a housing including an inner cavity, an open end in fluid communication with the inner cavity, and a through bore extending from the inner cavity to an outer surface of the housing. In addition, the device comprises a connector coupled to the open end. The connector is configured to releasably engage a mating connector coupled to the subsea component. Further, the device comprises a burst disc assembly mounted to the housing within the through bore. The burst disc assembly is configured to rupture at a predetermined differential pressure between the inner cavity and the environment outside the housing.

Abstract: A method of, and system for, collecting and controlling hydrocarbons leaking from offshore sea bottom environments entail providing a concrete containment barrier and catenary gasket around the leak source, pumping concrete onto the catenary gasket, opening ports and valves in a containment vessel while it is positioned over the leak source, at least partially embedding the containment vessel in the pumped concrete, closing the ports and valves to capture leaking fluids, and communicating the fluids to the surface for further processing. The modular containment barrier may be placed around an existing or potential well site, or an operating well, abandoned well or sea bottom fissure to facilitate implementation of the method in the event of a leak.

Abstract: A subsea system including a frame including an intensifier, the intensifier providing structural support to the frame and capable of providing pressurized delivery fluid. The intensifier includes an intensifier chamber and a delivery fluid chamber separated by a piston, the intensifier chamber capable of receiving ambient pressure to provide a pressure on the delivery fluid through the piston. Also, a regulation system regulates the amount of ambient pressure communicated to the intensifier chamber to maintain the delivery fluid pressure substantially constant as the delivery fluid is depleted.

Abstract: A riser system connects a subsea source of hydrocarbons to a collection vessel. The system includes a riser, a lower end of the riser fluidly coupled to a seal stem, the seal stem in turn fluidly attached to a lower riser assembly through a polished bore receptacle. The upper end of the riser is connected to the collection vessel, the riser being maintained in a near vertical position. Methods of installing and using the riser systems for killing and cementing wells are described.

Abstract: An apparatus for blocking or capping a pipe end is disclosed. The apparatus includes a tubular body defining a central cavity having an inlet, an outlet, and an axis. The apparatus also includes a plurality of conical blocker rings mounted to an inner diameter surface of the tubular body within the cavity, at least some of the blocker rings being rigid and some of the blocker rings being compliant. The blocker rings are adapted to seal to a pipe end inserted into the central cavity. The rigid blocker rings have an outer diameter joined to an inner diameter of the central cavity, and the compliant blocking rings have an inner diameter smaller than an inner diameter of the rigid blocker rings and are adapted to seal around an exterior of the pipe when inserted from the inlet.