Abstract: A method is described for monitoring a fluid flow in a flow line from a location in a subterranean reservoir to a surface storage or production facility using the steps of employing sensors located in the wellbore, along the flow line and surface systems for monitoring flow conditions, establishing parameters which determine the hydrocarbon phases like liquids and gases, precipitation of solid components from the fluid flow as a result of changes in temperature, pressure and compositions, setting alert parameters relating to the precipitation parameters, and determining an operating profile representative of present conditions along the flow line, wherein the precipitation parameters, the alert parameters and the operating profile and extrapolation of the operating profile are represented in a single parameter space.

Abstract: Managing hydrates in a subsea includes a host production facility, a production cluster comprising one or more producers, a water injection cluster comprising one or more water injectors, a water injection line, and a single production line for directing production fluid from the one or more producers to the host production facility. The methods comprise placing a pig in the subsea production system, shutting in production from the producers, and injecting a displacement fluid into the subsea production system in order to displace the hydrate inhibitor and any remaining production fluids in the production flowline and to further move the pig through the production flowline. The method may also include further injecting displacement fluid into the subsea production system in order to displace the hydrate inhibitor and pig through the single production line and to the host production facility.

Abstract: A method for assembling a control module having a fixed part and a removable section. The method includes configuring the fixed part of the control module to be attached to a pressure supply line for receiving a fluid under pressure; providing in the fixed part a valve manifold that houses a hydraulic activated valve; detachably attaching the removable section of the control module to the fixed part; fluidly connecting an electrically activated valve of the removable section to the hydraulic activated valve such that the electrically activated valve controls the hydraulic activated valve; and configuring the electrically activated valve to electrically connect to a control section.

Abstract: A subsea structure flowline connection assembly has a subsea structure with a flowline therein, a junction plate affixed to the subsea structure so as to support a flowline connector thereon, a receptacle affixed to or adjacent to the junction plate, and a fly-in connector assembly having a connector thereon. The connector of the fly-in connector assembly being engaged with the flowline connector of the junction plate. The fly-in connector assembly having a flow passageway in communication with the connector of the fly-in connector assembly. The receptacle has at least one slot formed therein. The fly-in connector assembly has an insert member slidably received by the slot. The fly-in connector assembly has an actuator coupled to the connector thereof so as to allow an ROV to rotate an end effector so as to move the connector of the fly-in connector assembly toward the flowline connector.

Abstract: A system for interconnecting a floating rig and a riser assembly includes a rotating control device permitting pressurization of the riser assembly; and a sliding joint connected to the rotating control device, the sliding joint being longitudinally extendable and compressible while the riser assembly is pressurized. Another system includes a sliding joint including more than two telescoping sleeves, and the sliding joint being longitudinally extendable and compressible while the riser assembly is pressurized at the surface. An apparatus includes a sliding joint with multiple sets of telescoping sleeves, each set including at least two of the sleeves. Another apparatus includes a sliding joint with multiple radially overlapping seal assemblies.

Abstract: A method for control of liquid or liquid slugs in multi phase fluid pipelines, including a multiphase pipeline for the transportation of a fluid, consisting of mainly gas and some liquid such as water an/or gas condensate. The gas is evacuated via a gas separation unit connected to the multiphase pipeline to a second gas transport pipe, and the liquid is fed to a dedicated pipeline section acting as a buffer volume pipeline. The separation unit includes one or several vertical pipes connected at a distance from one another along the multiphase pipeline, whereby the gas is transported separately to a downstream processing facility on a platform or onshore or the like, and whereby the liquid proceeds to the loop which may preferably be an extension of the multiphase pipeline, or the liquid and gas may be re-combined and led in a common transport pipeline to the desired destination.

Abstract: Systems and methods for lifting drilling fluid from a well bore in a subsea formation are disclosed. Some system embodiments include a drill string suspended within a drilling riser to form the well bore, and a drilling fluid source for supplying drilling fluid through the drill string during drilling. A diverter is coupled between the drilling riser and a return line, while a power riser coupled to the return line at an interface. A lift fluid source supplies lift fluid through the power riser into the return line. The lift fluid is intermittently injected from the power riser through the interface into the return line to form one or more slugs of lift fluid positioned between slugs of drilling fluid, such that the combined density of lift fluid and drilling fluid in the return line is less than the density of the drilling fluid alone.

Abstract: A travel joint (100) for space out operations in a wellbore. The travel joint (100) includes a generally tubular mandrel assembly (112) and a generally tubular housing assembly (102) slidably disposed about the mandrel assembly (112). The mandrel assembly (112) included an infinite slot (118) and at least one axial slot (120). A lock assembly (128) is positioned between the mandrel assembly (112) and the housing assembly (102). The lock assembly (128) is operable to selectively prevent and allow relative axial movement between the mandrel assembly (112) and the housing assembly (102). A floating lug ring (140) is positioned between the mandrel assembly (112) and the housing assembly (102). The floating lug ring (140) includes at least one lug (142) and is operable to rotate relative to the mandrel assembly (112) and the housing assembly (102) when the lug (142) travels in the infinite slot (118).

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 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: 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 tool for actuating a blow out preventer includes one or more connections for receiving hydraulic power from a remotely operated vehicle (“ROV”), a first pump for increasing pressure of an operating fluid for the blowout preventer (“BOP”), a second pump for increasing flow rate of the operating fluid, and a conductor for transporting the operating fluid to the BOP. The tool rapidly increases the pressure and flow rate of the fluid flowing to the BOP, and the BOP may be rapidly closed.

Abstract: Methods and apparatuses for controlling the flow of hydrocarbons from a structure or conduit are provided. An engagement apparatus having a body with threads disposed on an end is lowered into a position suitable for engagement with the structure or conduit, the threads including a deformable material. Rotation of the apparatus to engage the threads with the structure or conduit deforms the material to form a wedge shape that provides a seal between the apparatus and structure or conduit, and resists removal of the apparatus from the structure or conduit. Additional conduits can be secured to the upper end of the apparatus, in combination with a valve. The valve can direct the flow of hydrocarbons from the structure or conduit to selected additional conduits, enabling vessels and/or containers to be removed and/or replaced without wholly ceasing the flow of hydrocarbons in a manner that could cause a buildup of pressure.

Abstract: A method for managing hydrates in a subsea production system is provided. The production system includes a host production facility, a control umbilical, at least one subsea production well, and a single production line. The method generally comprises producing hydrocarbon fluids from the at least one subsea production well and through the production line, and then shutting in the production line. In addition, the method includes the steps of depressurizing the production line to substantially reduce a solution gas concentration in the produced hydrocarbon fluids, and then repressurizing the production line to urge any remaining gas in the free gas phase within the production line back into solution. The method also includes displacing production fluids within the production line by moving displacement fluids from a service line within the umbilical line and into the production line. The displacement fluids preferably comprise a hydrocarbon-based fluid having a low dosage hydrate inhibitor (LDHI).

Abstract: Apparatus and methods are described for subsea control system testing including one or more of electrical, optical and fluidic conduit testing, wherein the testing is conducted subsea using a subsea testing skid. In one embodiment of the invention a subsea pipeline service skid is provided that includes at least one skid mounted pump dimensioned to deliver from about 3000 to about 20000 p.s.i. of pressure for pressure testing the fluidic conduits to desired pressures. Modular construction of the skid permits customization for testing service of unique subsea control equipment.

Abstract: A system for remediating hydrates has a heat storage box with an interior volume, a heater for heating fluid flowing into the hot fluid inlet of the heat storage box, a heat exchanger positioned in the interior volume of the heat storage box so as to be in heat exchange relationship with heated water from the interior volume of the heat storage box, and a line connected to a heated water outlet of the heat exchanger so as to be manipulated toward a location of the hydrates for the purpose of delivering the heated water toward the hydrates. The heat exchanger is piping extends in a serpentine pattern within an upper portion of the heat storage box. The line can be connected to a hot stab suitable for a manipulation by an ROV.

Abstract: The present invention is a blowout preventer including a large frustoconical funnel. The large end of the funnel is placed over a well pipe (or other pipe) through which oil (or gas or other fluid) is blowing out. The small end of the funnel is connected to a return pipe. A high pressure pipe with a smaller diameter is inserted into the well pipe. Air is pumped under high pressure through the high pressure pipe, separating the oil and forcing the oil, that is not kept down in the well pipe by the pressure, up through the return pipe. The funnel can be moved into alignment with the well pipe using jets. There are sensing devices on moveable arms. A stopper is forced into the well pipe. There are one-way valves in the stopper. There are stacked turbines in the return pipe. There is a gasket with pivoting overlapping plates.

Abstract: Method, riser assembly and gas handler for diverting gas from a riser. The riser assembly includes a riser having a first end and a second end and a conduit extending from the first end to the second end; a gas handler connected to the riser and provided between the first end and the second end, the gas handler having an external casing; plural pipes attached to an outside of the riser such that at least one pipe of the plural pipes enters through the external casing; and a gas vent pipe configured to start at the gas handler and extend towards the second end of the riser and the gas vent pipe is further configured to divert a gas from the gas handler through the outside of the riser.

Abstract: An acoustic modem located on a blowout preventer stack communicates with a running tool acoustic modem located on a subsea running tool disposed within a subsea wellhead, tree or tubing spool. The acoustic modem and the running tool acoustic modern transmit and receive acoustic signals through a column of fluid in the blowout preventer stack. The acoustic modem is communicatively coupled to a subsea electronics module located on the blowout preventer stack and further communicatively coupled to a central control unit located on a platform at the surface. The running tool acoustic modem is communicatively coupled to a controller that receives data from sensors on the running tool and sends operational signals to functions of the running tool. An operator at the surface may control the running tool through the acoustic modems, and the running tool may communicate the running tool status to the operator through the acoustic modems.

Abstract: An apparatus comprises a jet pump assembly affixed to a riser string and to a blowout preventer. The jet pump assembly comprises a conduit and a sealing assembly configured to accelerate a drilling fluid's return flow by a power fluid delivered by an umbilical connected to the conduit.

Abstract: An offshore unit includes a hull and/or a deck frame, a mat attached to at least one connecting leg or a spud can attached to each of at least one connecting leg or lower hull attached to at least one connecting means. A wellhead deck is removably attached to the hull and/or deck frame and a sub-sea clamp in conjunction with a caisson or a sub-sea conductor frame is removably attached to the mat or to the at least one connecting leg, where a spud can is attached to each of the at least one connecting leg, or to the lower hull. The offshore unit is relocatable and is a platform or a rig capable of performing drilling, production, construction, accommodation, hook-up and commissioning or a combination of any of these functions thereof. The offshore unit is a self-elevating mobile platform or submersible platform or semi-submersible platform.

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: A pressure relief device is used to relieve pressure in a void within a wellhead housing. In one embodiment, the pressure relief device includes a plunger having a stepped plug, wherein the plug can be fully open to allow flow from the void, restricted to allow a predetermined flow to relieve pressure, or closed to prevent flow from the void. In another embodiment, the pressure relief device includes a vacuum puller that creates negative pressure in a vessel. As fluid in the void expands, it is able to enter the space formerly occupied by the plunger. In yet another embodiment, a rupture disc is used to prevent fluid from flowing from the void, through a passage, to the wellbore. If pressure in the void exceeds a predetermined value, the rupture disc yields and allows the trapped fluid to flow to the wellbore.

Abstract: A hydraulic coupler for providing fluid communication between adjacent members that includes a two way check valve formed from a double headed poppet set in a hollow cylinder with corrugated bellows like walls. Contoured bores are provided in the cylinder ends and the poppet heads are profiled to match the contour of the bores. When the heads are seated in the bores they form a sealing surface to block fluid from flowing through the coupler. Compressively preloading the cylinder before assembly provides a sealing force between the heads and the bores. Axially compressing the cylinder with respect to the poppet unseats the heads from the bores to form a flow path through the coupler.

Abstract: Disclosed is a process and system for circulating fluid within the annulus of a flexible pipe used in a riser in an offshore hydrocarbon production facility. Fluid, such as corrosion inhibitors, can be circulated in a closed loop which includes the annulus of the riser terminating at a platform or floating vessel, a fluid storage tank located on the platform or vessel and an umbilical tube terminating at the platform or vessel and at a subsea location. Use of the system to flow the fluid through the annulus can prevent or reduce corrosion of the steel members within the annulus and increase the fatigue life of the riser.

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: An Oil/Gas Recovery System, a Rotating Encasement Fitting (REF) and Methods of Using. The Oil/Gas Recovery System comprises a flexible shroud open at an end facing a leaking drill line arising from the bottom of a body of water, a recovery system operably coupled to the flexible shroud by an intake line, and a delivery system, operably coupled to the flexible shroud by a delivery line. The flexible shroud is adapted to be lowered or raised in a body of water, so that the open end encloses a source of crude oil or gas to be recovered. The Rotating Encasement Fitting (REF) for sealing a compromised pipeline fracture, comprises bladder glands at each end of the REF and a pipeline having a fracture therein. The bladder glands can be activated by a supply line or remotely supplied for multiple charges.

Abstract: A device for capturing hydrocarbons discharged from a subsea flow passage comprises an elongate tubular structure having a central axis, a first end, and a second end opposite the first end. The second end is open and in fluid communication with the first end. The tubular structure includes a rigid stabbing member extending axially from the second end and configured to he inserted into the flow passage. In addition, the device comprises an annular flexible skirt disposed about the stabbing member. The skirt is secured to the stabbing member and extends radially outward from the stabbing member. The skirt is configured to flex from an unflexed position to a flexed position upon insertion of the stabbing member into the flow passage. The skirt is biased to the unflexed position and has an outer diameter in the unflexed position that is greater than the inner diameter of the flow passage.

Abstract: A method of flushing a wellbore fluid from a downhole tool containing a bearing package includes pumping hydraulic oil through at least one of a hydraulic inlet line and at least one of a pneumatic inlet line connected to the main housing and into an annulus formed between the bearing package and a main housing of the downhole tool, wherein the hydraulic oil replaces the wellbore fluid in the annulus, removing the wellbore fluid from the annulus through at least one hydraulic outlet line and at least one pneumatic outlet line connected to the main housing, pumping air through the at least one pneumatic inlet line connected to the main housing and removing the hydraulic oil from the at least one pneumatic inlet line connected to the main housing, and removing the hydraulic oil through at least one pneumatic outlet line connected to the main housing.

Abstract: An apparatus to allow backup or alternate fluid flow routes around malfunctioning BOP control components using a remotely installed removable hydraulic hose connection. The backup fluid flow route sends pressure-regulated hydraulic fluid to a BOP operation via an isolation valve rigidly attached to the BOP, then to a hose connected to an intervention panel on the BOP and finally through a valve that isolates the primary flow route and establishes a secondary flow route to allow continued operation. To increase reliability, the backup components route from a spare BOP function and are rigidly fixed to the BOP.

Abstract: A fitting includes a body having at least two portions coupled together to form a body having a passage through the body. The passage allows at least a portion of a conduit to be located at least substantially lengthwise within the body. First and second ports are located on the body and are in fluid communication with the passage. A first seal is located on the passage wall between a first end of the body and the first port. A second seal is located on the passage wall between the first port and the second port. A translatable ring is located on the passage wall between the first and second seals. The ring moves along the passage wall when the first seal is activated so that the second seal is activated. The ring includes an opening proximate the first port to provide access to the conduit from the first port. The first and second seals provide a seal in the passage.

Abstract: An offshore riser system has riser joints, each having a pin and a box. The pin has an external grooved profile that is engaged by a locking element carried by the box of another riser joint. An actuating ring engages with the locking element to move it into the locked position. A retractable spider supports the string of riser while the new joint is being made up. A makeup tool on the riser deploying floor moves the ring relative to the locking element, causing the locking element to move to the locked position.

Abstract: According to an embodiment, a method of limiting the amount of oil in a sea comprises: positioning a device for directing the flow of a fluid adjacent to a wellhead, wherein the device comprises: a first fluid passageway; a second fluid passageway; a third fluid passageway, wherein the first fluid passageway is operatively connected to the second and third fluid passageways; and a fluid director, wherein the fluid director is operatively connected to the first, second, and third fluid passageways, and wherein depending on at least one of the properties of a fluid, the fluid director directs the fluid to increasingly flow into the second or third fluid passageways. This embodiment is useful in limiting the amount of oil when a blowout has occurred.

Abstract: Pressure within a subsea well is managed as temperature within the well fluctuate. The management of the pressure mitigates stress to the structure of the well caused by the pressure. To manage the pressure, fluid is received from and/or provided to the well to reduce and/or increase pressure within the well.

Abstract: Subsea test apparatus comprises: a connector for mating with a corresponding connector of subsea apparatus to provide at least one of electrical, optical, and fluid connection between the test apparatus and the subsea apparatus; measuring means connected to the test apparatus's connector and operable underwater in a measurement mode; a power supply arranged to power the measuring means; and disconnection means for disconnecting the test apparatus's connector from a mated subsea apparatus's connector. The measuring means, in said measurement mode, is arranged to perform at least one measurement, via the mated connectors, on connected subsea apparatus, and the test apparatus further comprises indicating means operable underwater and arranged to provide an indication of a result of the or each measurement.

Abstract: A mudline connector including a compression adaptor which can be elastically deformed onto an internal tubular member. The compression adaptor deflects inwardly to grip upper and lower sealing mandrels, providing axial and bending load support and creating a seal to isolate bore pressure from an outer annulus. The clamping arrangement provides a sealed connection between two well casing sections extending in opposite axial directions. The well casings are gripped and held in an end to end configuration by a radial load applied internally by a compression ring. The connector is activated by introducing pressure to activate pistons which in turn provide an axial thrust to stroke the internally tapered compression ring along the externally tapered compression collar, effectively creating an interference fit therebetween. This deflects the inner surface of the compression collar inwardly, deflecting the compression adaptor inwardly to grip the outer surfaces of the upper and lower sealing mandrels.

Abstract: A chemical injection line connector includes first and second couplings configured to automatically seal shut when the members are disengaged. A method for blocking contamination or pressure transfer of chemical injection lines includes securing first and second couplings to corresponding ends of a chemical injection line and automatically sealing the couplings shut when the couplings are disengaged.

Abstract: A system including a combined plug and valve device that may be precisely delivered to and inserted into an uncontrolled undersea oil well. Once positioned in the well, the device is operated in graduated fashion to anchor the plug to the well and gradually stanch the flow of oil from the well.

Abstract: A subsea wellhead assembly positions a flow module between an outboard flowline of a subsea tree and a tubing hanger spool flowline. The subsea production assembly includes a wellhead, a tubing hanger spool disposed on the wellhead, and a subsea tree disposed on the tubing hanger spool. Production fluid may flow from the wellhead through the tubing hanger spool, and then through the tree. A tubing hanger spool frame mounts to and extends laterally from the tubing hanger spool and supports a downstream flowline having an upward facing hub. A tree frame mounts to and extends laterally from the subsea tree and supports an upstream flowline having an upward facing hub. A flow module having downward facing flowlines that couple to the hubs so that the weight of the flow module is distributed between the frames of the tubing hanger spool and the subsea tree.

Abstract: An apparatus for venting an annular space between a liner and a pipeline of a subsea riser used for conveying hydrocarbons, the apparatus comprising a permeate recovery device for recovering permeate passing through the liner into the annular space. The permeate recovery device includes a first vent port in a wall of the pipeline at or adjacent a lower region of the pipeline and communicating with a permeate recovery line defining a flow path between the annular space and a permeate collection vessel. A one-way valve is associated with the permeate recovery line for preventing flow from the permeate recovery line into the annular space. A gaseous permeate recovery line connected to a second vent port at an upper region of the pipeline defining a flow of gaseous permeate from the annular space.

Abstract: A subsea completion testing tree (SCTT) for connection in a tubular string includes a lower tree portion having a control valve; an upper tree portion separably connected to the lower tree portion at a latch; a circulation valve connected with the upper tree portion; and a retainer valve connected with the upper tree portion between the circulation valve and the latch.

Abstract: A technique enables a simplified approach for providing subsea hydraulic control. A subsea installation comprises one or more devices that are actuated hydraulically. A simple signal carrier, such as a wireline logging cable, can be routed down to the subsea installation. However, hydraulic fluid for controlling the one or more hydraulic devices in the subsea installation is delivered via an open water umbilical that extends to the subsea installation from a separate workover control system.

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 method and an apparatus for establishing a hydrate free regime in a subsea production flowline before discharging into the subsea production flowline a production flow of hydrate prone hydrocarbon product pursuant to a shutdown or at an initial start of production. The hydrate free regime is achieved by injecting into the flowline a heated water volume in advance of discharging the hydrocarbon product from the subsea production system.

Abstract: An apparatus that includes a chemical-injection management system. The chemical-injection management system may include a tree interface configured to couple the chemical-injection management system to a tree and a positive-displacement flow meter.

Abstract: A wellhead system for producing hydrocarbons from a subterranean formation that includes concentric tubulars that form an annulus. The annulus is vented by flowing fluid from the annulus through a bleed line having a valve that is selectively opened and closed. Upstream of the bleed line valve, the bleed line is routed adjacent a production flow line. The temperature of the fluid in the production flow line is greater than annulus temperature and warms the bleed line. Hydrate formation in the bleed line is thereby inhibited by the thermal energy it receives from the production flow line.

Abstract: In a subsea system where subsea devices are operated using a pressurized fluid from one or more accumulators, the method of providing flow of pressurized fluid to operate a device which is greater than the flow from an accumulator providing the flow, comprising discharging the accumulator to drive one or more motors, driving one or more pumps by the one or more motors, the one or more pumps having a larger displacement than the one or more motors such that the one or more pump outputs a greater volume of fluid than the motor consumes, and delivering the output of the one or more pumps to operated the subsea device.

Abstract: A pressure relief device is used to relieve pressure in a void within a wellhead housing. In one embodiment, the pressure relief device includes a plunger having a stepped plug, wherein the plug can be fully open to allow flow from the void, restricted to allow a predetermined flow to relieve pressure, or closed to prevent flow from the void. In another embodiment, the pressure relief device includes a vacuum puller that creates negative pressure in a vessel. As fluid in the void expands, it is able to enter the space formerly occupied by the plunger. In yet another embodiment, a rupture disc is used to prevent fluid from flowing from the void, through a passage, to the wellbore. If pressure in the void exceeds a predetermined value, the rupture disc yields and allows the trapped fluid to flow to the wellbore.

Abstract: A pressure driven pumping system includes a piston disposed within a first bore of a housing to separate a process chamber from a working chamber. A rod member coupled to the separating member extends into a reduced pressure chamber. The piston has a first face exposed to the process chamber and a second face exposed to the working chamber. The second face has an effective area less than an effective area of the first face. The housing may be placed in seawater at a selected depth. The process chamber can be in fluid communication with a well to pass well fluid into the process chamber at well pressure to move the piston, to discharge seawater from the seawater chamber. The working fluid, typically seawater in a subsea application, is pumped into the working chamber to move the piston, which discharges well fluid from the process chamber.

Abstract: An RCD is used to provide a system and method for sealing a marine riser having a rotatable tubular. A bypass internal channel or external line may be used to allow fluid to bypass the RCD seal. An RCD seal assembly seal could be a mechanically extrudable seal or a hydraulically expanded seal to seal the RCD with the riser.