Abstract: There is provided a high power laser riser blowout preventer system and controller for operation thereof. The system utilizes high power laser cutters that are associated with the riser and the blowout preventer to provided an integrated operation to quickly weaken or cut tubulars to address potential emergency and emergency situations that can arise during deep sea drilling.

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: An orientation joint for a subsea landing string equipped to maintain both unitary and telescoping configurations. For example, the joint may maintain a unitary configuration to provide continuous orientation definition while lowering a landing string within a blowout preventer (BOP). Additionally, the orientation joint may be configured to telescope and provide an appropriately sized uniform outer diameter surface to enable a sealing engagement with an aligned ram of the BOP.

Abstract: A method for severing a tubular of a wellbore is provided. The method involves positioning a blowout preventer about a tubular, the blowout preventer having a plurality of rams slidably positionable therein and a plurality of blades carried by the rams for engaging the tubular. The method further involves piercing the tubular with a piercing point of at least one of the blades such that a portion of the tubular is dislodged therefrom, and raking through the tubular with a cutting surface of at least one of the blades.

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: A grapple for controlling, monitoring and stopping the flow of oil, natural gas and the like from a broken, flanged pipe. A housing encloses a ring of material that is more ductile than the broken pipe flange. The force applied by a weight, presses a driving device against the broken pipe flange periphery, the force so applied distorts the ductile ring, thereby establishing a fluid-tight seal between the flange and the housing.

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: Present invention regards a device for injection and stimulation of fluids in a wellbore, where the device is typically is installed in Christmas trees, wellheads or subsea. The device comprises two separable sections, where the section that is mounted/arranged within the Christmas tree or wellhead, will remain in a closed position even if the other section due to external forces is broken off or in other ways is damaged.

Abstract: A stabplate connection is provided by: providing a first part (1) comprising a stabplate and carried by an underwater structure; providing a second part (2) comprising a stabplate carried by tooling (4); engaging the tooling with said first part; using the tooling to bring the parts together so the stabplates mate with each other; using the tooling to lock the first and second parts together by engaging a portion (6) carried by the first part with a portion (10) carried by the second part; disengaging the tooling from the first part; and removing the tooling from the stabplate connection.

Abstract: A blow out preventer comprises a valve casing assembly, a tubing cutter, a hydraulic cylinder and piston, and a linkage assembly. The valve casing assembly has a first port and a second port. The ports are in axial alignment along a longitudinal axis extending between the ports. The well tubing is run through the ports and transversely through the tubing cutter. The tubing cutter is rotatably positioned in the casing assembly and is rotatable from a first position to a second position. The tubing cutter has an axis of rotation which is transverse to the longitudinal axis of the valve casing assembly. The piston is annularly shaped and moves parallel to the longitudinal axis of the valve casing. Linkage between the piston and the tubing cutter converts the axial movement of the piston into rotational movement of the tubing cutter to shear the tubing when needed. When the tubing has been sheared, a seal is formed between a face of the tubing cutter and a valve seat in the valve casing assembly.

Abstract: removable blowout recovery valve. The large end of the valve (or funnel) is placed over a well pipe (or other pipe) through which oil (or other fluid) is flowing out. The small end of the valve is connected to a return pipe. A high pressure pipe with a smaller diameter is inserted into the well pipe. A sleeve connected to the return pipe is placed over the well pipe. A locking collar is attached to the sleeve. Positioning rings are attached to the high pressure pipe, that can fit inside the well pipe. A sharp edge extends from the sleeve, by which irregularities in the well pipe can be cut. Lasers or other cutting devices are attached to extension arms, that can also cut irregularities in the well pipe. The slope of the valve can be changed. The valve can be removed and raised with the aid of floats.

Abstract: A distributed function control module adapted for use in a modular blowout preventer (BOP) stack for use subsea comprises a housing, adapted to be manipulated by a remotely operated vehicle (ROV) with a stab portion adapted to be received into a BOP stack control module receiver. Control electronics, adapted to control a predetermined function with respect to the BOP stack, are disposed within the housing and connected to one or more controllable devices by a wet mateable connector interface.

Abstract: A wellbore control device for use in a blow out preventer is described. The control device comprising a housing defining a throughbore, a gate, the gate being movable between a throughbore open position and a throughbore closed position, a first stem attached to the gate and a second stem releasably engageable with the gate, the first and second stems being arranged such that a portion of each stem is exposed to an internal housing pressure and a portion of each stem is exposed to an external housing pressure. When the internal pressure is greater than the external pressure, the pressure differential results in a force being applied to the gate to move the gate to, or retain the gate in, the throughbore closed position.

Abstract: A remote operated vehicle (ROV) interface has a retrievable portion and a permanent portion. The permanent portion includes a housing that has a cavity that secures to a drive stem of the subsea well device. The housing has a pod cavity on an opposite end that receives a pod body, which is part of the retrievable portion. The pod body is secured by spring-biased retainer within the pod cavity. The pod body has a cylindrical receptacle that receives a drive pin, which forms another part of the retrievable portion. The drive pin and the cylindrical receptacle are engaged for rotation by a shear element. The pod body has an ROV retrieval profile that is accessible by an ROV. In the event the shear element shears due to excessive torque, an ROV retrieval tool engages the pod body and retrieves the pod body along with the drive pin.

Abstract: A dual-BOP or multi-BOP self-standing riser configuration is disclosed, including at least a riser or another similarly fixed tubular structure disposed in communication with an associated drilling vessel and a subsurface well. The system supplements the traditional mud-line level BOP with one or more additional near-surface BOPs, which are tensioned using an adjustable buoyancy chamber rather than by means of a vessel-born tensioning device.

Abstract: The invention features an encapsulating device and system to contain a fluid or substance spilled during a blowout of a pipe at subsea level. The system features a semi-circular housing that fits underneath the flange of a pipe. A heater is provided inside the housing. The system features a tri-flange system having flanges on the top and sides of the housing. The side flanges are closed and sealed and then the top flange is closed. Side flanges divert pressure in the system. The system discloses arms and sealants to aid in sealing the pipe.

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: Apparatus and method for containing and recovering undersea oil or gas well leakage by reason of the leaked fluid being lighter than sea water may include a canopy, or a series of interconnected canopies, which, when placed over a leak site, allow leaked fluid to be captured and displace sea water with the canopy or series of canopies having an arrangement, such as one or more conduits, for flow of leaked fluid upward from a respective canopy to the surface. With a system with multiple canopies in a series with exit arrangements for leaked fluid from a lower canopy to a next upper canopy, the series can readily extend from the surface to a great depth and allow transfer of volumes of the leaked fluid that are not limited by the capacity of canopies or conduits at deep locations.

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: 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: 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 protective device for a blow out preventer stack (B.O.P.), and a sidetracking method using same during an oil-field milling or drilling operation requiring a window to be formed in casing (14) to access a formation, the device having a sleeve assembly (2) and a running tool releasably attached to the sleeve assembly, wherein the running tool comprises a miming tool housing (4) connected to the sleeve assembly and a separable miming tool body (5) connectable within the length of a work string (6) having a BHA with a mill or bit (30), the running tool housing being shear pinned to the running tool body for running in hole, wherein the miming tool housing is configured to shear from the running tool body during deployment into a cased wellbore to sealingly seat the sleeve assembly within a B.O.P. and form a barrier to ingress of swarf into the B.O.P.

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: A valve useable in an undersea apparatus for generating a force for closing a blowout preventer (BOP) based on a pressure difference between a low pressure recipient and ambient pressure, an apparatus including the valve and related methods are provided. The valve includes a valve body enclosing a chamber with an input port selectively connectable to an output port, and a chamber separating assembly configured to separate the chamber from a region of different pressure. The assembly includes (1) a backup plate having a first portion of a first diameter towards the chamber and a second portion of a second diameter larger than the first diameter, towards the region, and (2) an upper seat located between the first portion of the backup plate and the valve body.

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: A containment vessel is moved proximate to and preferably surrounding the wellhead, such that leaking oil enters an interior chamber of the vessel. A fluid pump of the containment system is actuated to flow leaking hydrocarbon fluid through a conduit toward a collection sump. A controller controls the speed or volume of a fluid pump to maintain suction force within the interior chamber, or the pressure at wellhead annulus site (PWAS) at a set point that is based on seabed pressure.

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 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: A method and apparatus for stopping oil flowing from the end of a ruptured pipe or other device, by mounting a flange on the end of the ruptured pipe or device, if a flange is not already present; providing a gate valve having a flange on its lower end to mate with the flange on the ruptured pipe or device; providing a permanently affixed gasket member on the mounting flange of the gate valve; lowering the gate valve to the depth of the flowing oil from the ruptured pipe or device; providing at least two flexible bolts through opposite openings in the flange of the gate valve; while the gate valve is situated adjacent the flowing pipe or device, threading each flexible bolt through two opposite openings in the flange of the ruptured pipe or device; placing pulling pressure on the lower ends of the two flexible bolts to pull the gate valve from a position adjacent the ruptured pipe or device to a second position where the gasket of the gate valve mounts against the face of the flange of the ruptured pipe or de

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: A method of servicing hydrocarbon production equipment comprising locating at least a portion of a hydrocarbon flow conduit experiencing a loss of functionality; creating a port to access an interior flow bore of the hydrocarbon flow conduit; installing at least one piece of equipment proximate the access port, wherein the equipment has access to the interior flow bore via the access port; and placing a servicing composition into the conduit via the access port, wherein the servicing composition prevents the loss of materials from the interior of the hydrocarbon flow conduit to the surrounding environment.

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: An oil recovery system recovers oil released at the bed of a body of water. The system includes a fluid collector assembly positionable proximate to the bed of the body of water. The collector assembly has an open lower end to receive fluid and has an upper end coupled to a lowermost fluid transfer tube. Fluid transfer tubes are interconnected in a string between the lowermost fluid transfer tube and a vessel positioned to receive fluid transferred through the fluid transfer tube. A guide cable is anchored at the bed of the body of water to guide the fluid collector assembly and the fluid transfer tubes to the bed. A lift cable selectively lowers the fluid collector assembly and the fluid transfer tubes to the bed. Fluid entering the collector assembly rises to the water surface via the transfer tubes.

Abstract: Provided is a system, including a first module (35b) configured to process fluid from a well, wherein the first module (35b) has an extension conduit (5b), having a connection that is coupleable to a central mandrel of a manifold (5), a processing device arranged in a region surrounding the extension conduit (5b), a processing input (18a), and a processing output (19a). Further provided is a method of processing well fluids, including diverting fluids from a bore of a manifold (1) to a processing module (35b), wherein the processing module (35b) is coupled to a mandrel of the manifold (5), processing the fluids in the processing module (35b), and returning the fluids to a flowpath (19a) for recovery.

Abstract: Two functionally and physically integrated subsystems form a supplemental disaster preventive system for offshore oil wells. A multi-function well subsystem modifies the sea-floor and in-well equipment to provide maintenance access, tools to cap the well, seal/re-seal the well, drill/re-drill the well, kill the well from the top, improve BOP reliability, add BOP functional redundancy, improve the cementing process, incorporate a sea-floor pressure relief/diversion function and improve the well's life cycle safety. A dome top cylindrical sidewall structure encloses the well's sea-floor equipment providing improved structural strength as well as passive protection from natural/human induced disasters. An intrusion detection and response subsystem provides sensing, processing and communication devices to detect, track & classify the 3D aspects of air/surface/sub-surface objects around a specific oil well or group of oil wells and provides the means to evaluate and eliminate threats.

Abstract: A tensioning apparatus for applying a substantially constant tension to a workover riser (12) includes a first portion (40) adapted to be coupled to a workover riser, a second portion (44) adapted to be coupled to a marine riser (14) and tensioning means (46) for providing relative movement between the first portion and the second portion to, in use, tension, the workover riser.

Abstract: A modular pressure management oil spill containment system is constructed on the floor of an ocean to contain an oil spill caused by a wild well blowout. A base containment module including a hollow wall and at least one pressure relief valve is submerged below a surface of the ocean, positioned on a portion of the ocean floor that circumvents the wild well and its hollow wall is reinforced. At least one additional containment module including a hollow wall and at least one pressure relief valve is submerged below the ocean surface, positioned on top of the base containment module and its hollow wall is also reinforced. A plurality of riser assemblies are connected between at least a portion of the pressure relief valves of the containment modules and at least one containment vessel. The pressure relief valves are controlled to manage the containment of the oil spill.

Abstract: Method and device to be used for resetting a pressure in a low pressure recipient connected to a subsea pressure control device. The device includes the low pressure recipient configured to have first and second chambers separated by a first piston; a reset recipient configured to have third and fourth chambers separated by a piston assembly, and the piston assembly includes a second piston having first and second extension elements that extend along a direction of movement of the piston assembly. The third chamber has an inlet configured to allow the hydraulic liquid to enter the third chamber and an outlet configured to allow the hydraulic liquid to exit the third chamber, and the fourth chamber has an inlet configured to allow the hydraulic liquid to enter the fourth chamber and an outlet configured to allow the hydraulic liquid to exit the fourth chamber.

Abstract: Year 2010 showed us that the oil/gas industry was not prepared to shut down in few days a high pressure oil/gas well. The Gulf of Mexico was polluted by thousands of barrels of oil that were leaking from a high pressure well. The environment damage was humongous as well as the economical loses. Here, I am presenting a method to shut down a high pressure oil/gas well in matter of days rather than in months. This method keeps the well integrity. This method is effective even if the well integrity was compromised.

Abstract: The disclosure provides a subsea overload release system and method. The disclosure provides a releasable connection system than can be overridden during an overload condition, and is resettable in a subsea location in situ. During normal operation, a collet sleeve is slidably engageable with a collet having one or more fingers that can releasably couple a first member with a second member. During an overload condition, an overload piston acting on fluid in an overload reservoir causes an overload pressure and a rupture or other release of fluid through an overload pressure member, causing the overload reservoir to at least partially collapse. The collapse allows the system to extend and force open the fingers to disengage the second member from the first member. When the overload symptom is rectified, the overload reservoir can be reset and the overload pressure member reset or replaced without requiring repairs above sea surface.

Abstract: The present invention is a blowout preventer including a large frustoconical funnel, made of metal or other material. 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 Bernoulli effect keeps the funnel on the well pipe. A gasket at the top end of the channel prevents leaks. Channels and rotating blades near the top of the funnel accelerate the flow, reducing pressure and increasing the suction due to the Bernoulli effect.

Abstract: A first method of controlling underwater oil well leaks is to place heavy metal javelins into the ruptured pipe. A second method is to fabricate or drop a series of self-stacking exterior collars around or over the ruptured pipe.

Abstract: A method and apparatus are described for containing an oil spill caused by a subsea blowout. A blowout preventer (BOP) stack, located on a floor of an ocean, may be circumvented with a hollow wall of a cylindrical containment assembly. The containment assembly may be reinforced by filling the wall with cement. A valve assembly having a hollow cavity may be positioned on a top perimeter of the wall and may be reinforced by filling the cavity with cement. Alternatively, a cylindrical containment assembly may be positioned such that a wall of the assembly circumvents a portion of a floor of an ocean where a subsea blowout occurred and at least one of oil or gas is spewing into the ocean. The wall may be reinforced with cement, a valve assembly may be positioned on a top perimeter of the wall, and the valve assembly may be reinforced with cement.

Abstract: A backup blowout assembly for a subsea wellhead that is positioned between an existing blowout preventer system and the wellhead. The backup blowout assembly includes an independently operated shear/blind ram assembly that attaches to a standard wellhead connector that connects to the wellhead. The ram assembly includes an upper neck with an upper flange on which a dual housing assembly is attached. The dual housing assembly includes a primary housing longitudinally aligned over a secondary housing. The primary and second housings include lower bodies and upper necks that have identical diameters. During assembly, the existing primary blowout assembly is initially connected to the primary housing and the ram assembly is connected to the wellhead connector. When a blowout occurs, the primary housing may be disconnected from the secondary housing to expose the upper neck of the secondary housing upon which a replacement primary blowout assembly system or cap may be attached.

Abstract: A system and method for rapidly responding to and regaining control of uncontrolled flow from offshore hydrocarbon wells, comprising a subsea containment assembly, optionally including a capture caisson assembly installed around the assembly, riser systems for production of hydrocarbons to capture vessels on the surface of the sea, and modularized subsystems facilitating communication between and fluid flow from the subsea containment assembly through the riser to the capture vessel.

Abstract: An apparatus and method for capping an oil well such as an underwater oil well comprising a pipe extending from the vicinity of the oil well head to the sea surface. Optionally, the pipe is equipped with a pump. A pile of large objects such as boulders is disposed around the lower end of the pipe. Preferably, smaller objects are disposed around the larger objects forming a first canopy. Additional canopies of progressively smaller objects are disposed about the first canopy, defining a pile. One or more of the canopies may include a cement mixture. An impermeable membrane may be included within to the pile. The size and weight of the pile is sufficient to prevent oil leakage to the sea. The entire flow from the well head thus may be drawn through the pipe by an optional pump, or the well may be shut off by closing the pipe.

Abstract: The present invention is embodied in systems and methods for mitigating temperature-related pressure buildup in the trapped annulus of an oil or gas well, wherein such systems and methods employ production and/or tieback casing having one or more pressure mitigating chambers, and wherein such chambers make use of pistons, valves, and burst disks to mitigate pressure increases within the annulus.

Abstract: A system for and method of limiting and controlling the unintended subsurface release of an exploration or production riser system is provided including one or more means for anchoring the riser or casing stack at one or more pre-determined points upon the length of the riser, and/or on the housing of an associated buoyancy chamber or the like, and/or on a particular portion of the riser as dictated by the operational environment, and/or on an anchor portion secured in the sea floor; and a network of restraining members disposed on the anchoring means. A lower anchoring portion includes one or more anchors disposed in communication with a wellhead, or with the sea floor or below the sea floor mud line, or with a well casing portion. A network of restraining members forms an essentially continuous connection from the buoyancy member portion to said bottom anchor portion.

Abstract: A method and apparatus are described for stopping oil and/or gas from spewing from a defective blowout preventer (BOP) stack located on a floor of an ocean by entombing the defective BOP stack. A containment assembly, which is lowered below a surface of the ocean, includes a hollow wall and a large diameter high pressure valve mounted on an upper opening of the containment assembly. The large diameter high pressure valve is maintained in an open position. The containment assembly is positioned on a portion of the ocean floor such that a hollow inner cavity of the containment assembly circumvents the defective BOP stack. The hollow wall is filled with reinforcement material via a first set of valves, and the hollow inner cavity is filled with reinforcement material via a second set of valves. The upper opening may also then be filled with reinforcement material.

Abstract: An arrangement and a method to control and regulate the bottom hole pressure in a well during subsea drilling at deep waters: The method involves adjustment of a liquid/gas interface level in a drilling riser up or down. The arrangement comprises a high pressure drilling riser and a surface BOP at the upper end of the drilling riser. The surface BOP havs a gas bleeding outlet. The riser also comprises a BOP, with a by-pass line. The drilling riser has an outlet at a depth below the water surface, and the outlet is connected to a pumping system with a flow return conduit running back to a drilling vessel/platform.