Blowout Preventer Actuation System

This is a Continuation-in-Part application of U.S. application Ser. No. 18/105,879 filed on Feb. 6, 2023, which is incorporated herein by reference in its entirety.

This disclosure relates to the field of well pressure control apparatus, known as blowout preventers (BOPs). More specifically, this disclosure relates to techniques for operating or actuating BOPs when the need for such action becomes apparent.

BOPs for oil or gas wells are used to prevent potentially catastrophic events known as blowouts, where high pressures and uncontrolled flow of fluid from a subsurface reservoir can blow tubing (e.g., drill pipe and well casing), tools and drilling fluid out of a wellbore drilled through such reservoir. Blowouts present a serious safety hazard to drilling crews, the drilling rig and the environment, and can be extremely costly.shows a conventional BOP systemdeployed underwater on a wellhead at the sea floor.is an enlarged view of the BOP systemto illustrate certain components. Actuation of the BOP systemis controlled from a control panel (not shown separately) disposed at the sea surface and in signal communication with a controller. The controllermay be linked to the BOP systemthrough multiplex (MUX) communication cables. The BOP systemis provided with two subsea control pods, conventionally designated as blueand yellowcontrol pods, and configured to actuate respective hydraulic accumulatorsto close rams in the BOP systemwhen required.

In the event of an incident requiring actuation of the BOP system, an operator will press a button on the control panel (not shown) to cause the controllerto send a signal to operate either the yellowor bluecontrol pod to actuate the respective hydraulic function and thereby supply hydraulic pressure to the BOP to actuate it. Since the BOP actuation system is hydraulically based, only one triggering signal can ultimately actuate the BOP rams or other BOP function (e.g., annular BOP, gate valves, etc.). For example, if the operator presses the button triggering the blue podand it fails to actuate, the operator must then operate a switch on the control panel to trigger the yellow pod. Nonetheless, only one hydraulic supply from one pod at a time (either blue or yellow) can actuate any part of the BOP, otherwise the hydraulic components are subject to jamming or malfunction. If both the blueand yellowpods fail to actuate, the operator must then use a backup actuating device (e.g., an acoustic signal system or physical actuation using a remotely operated vehicle (ROV) in the water). Independently initiating these BOP actuation devices can take considerable time, which may result in a catastrophic event in an emergency where rapid BOP actuation is critical. For example, when the Dynamic Position system on the rig fails, leading to the vessel drifting off position above the oil and gas well.

A need remains for improved techniques to rapidly and efficiently actuate BOPs, particularly when deployed underwater.

One aspect of the present disclosure is a blowout preventer actuation system including at least one hydraulically actuated blowout preventer; a kinetic blowout preventer configured with an initiator; at least one sensor disposed on the kinetic blowout preventer and configured to monitor an internal pressure parameter therein; wherein the at least one hydraulically actuated blowout preventer and the kinetic blowout preventer are configured for: (a) simultaneous actuation if the internal pressure parameter is at or below a predefined level; or (b) actuation of only the at least one hydraulically actuated blowout preventer if the internal pressure parameter is above the predefined level.

A method for actuating a blowout preventer according to another aspect of this disclosure includes disposing at least one hydraulically actuated blowout preventer at a site; disposing a kinetic blowout preventer configured with an initiator at the site; monitoring an internal pressure parameter in the kinetic blowout preventer with at least one sensor disposed thereon; wherein the at least one hydraulically actuated blowout preventer and the kinetic blowout preventer are configured for: (a) simultaneous actuation if the internal pressure parameter is at or below a predefined level; or (b) actuation of only the at least one hydraulically actuated blowout preventer if the internal pressure parameter is above the predefined level.

Illustrative embodiments of a well pressure control apparatus are set forth in this disclosure. In the interest of clarity, not all features of any actual implementation are described. In the development of any such actual implementation, some implementation-specific features may need to be provided to obtain certain design-specific objectives, which may vary from one implementation to another. It will be appreciated that development of such an actual implementation, while possibly complex and time-consuming, would nevertheless be a routine undertaking for persons of ordinary skill in the art having the benefit of this disclosure. The disclosed embodiments are not to be limited to the precise arrangements and configurations shown in the figures and as described herein, in which like reference numerals may identify like elements. Also, the figures are not necessarily drawn to scale, and certain features may be shown exaggerated in scale or in generalized or schematic form, in the interest of clarity and conciseness. As used herein, the word “fluid” is intended to include a gas, a liquid, and/or a combination of the two.

Pyrotechnic based BOPs which address certain shortcoming of hydraulically actuated BOPs include those such as described in U.S. Pat. Nos. 11,028,664 and 11,608,703, both issued to the present assignee and entirely incorporated herein by reference.shows a cross-section view of a pyrotechnic based (hereinafter referred to herein as “kinetic”) BOPaccording to an example embodiment of the present disclosure. The kinetic BOPcomprises a main body or housinghaving a through bore. The kinetic BOPalso has a passagethat is arranged transversely to the through bore. A shearing devicewith a cutting edge is located in the passageon a first side of the through bore.

A chargewhich may be in the form of a pyrotechnic chemical propellant is located between the shearing device and an end capdisposed at one longitudinal end of the passage. In some embodiments, the chargemay be a deflagrating charge. In some embodiments, the chargemay be an explosive charge. The chargewhen actuated produces pressure to propel the shearing devicealong the passageand across the through bore, closing off a wellbore (to which the main bodyis coupled) as described in U.S. Pat. Nos. 11,028,664 and 11,608,703. In some embodiments, the chargemay be actuated by an initiator. For example, the initiatormay be a detonator or a blasting cap.shows an initiatorin the form of a blasting cap. Actuating the chargeincludes actuating the initiatorin response to a control signal. For example, the initiatormay be actuated in response to a hydraulic signal or an electrical signal as will be further explained below. Some kinetic BOPembodiments may be configured with more than one initiator (not shown).

An arresting mechanism in the form of an energy absorption mechanismis located in the passageon a second side of the through bore. The energy absorption mechanismhas a body of energy absorbing material adapted to absorb the kinetic energy of the shearing device(see). The energy absorption mechanismis configured to slide within the passageon the second side of the through bore.

shows an example embodiment of a BOP stack according to this disclosure. A kinetic BOPmay be incorporated into a BOP stackdeployed underwater on the sea floor F. The BOP stackis coupled at one end to a risersuspended from a floating platformsuch as a ship at the sea surface as is known to be used in marine oilfield operations. In addition to the kinetic BOP, the BOP stackmay also comprise one or more conventional, hydraulically actuated BOPsof any type known in the art. Other embodiments may be implemented without hydraulically actuated BOPs, or may be implemented with a single, or multiple kinetic BOPs such as shown at.

shows an enlarged view of the end cap(See) of the kinetic BOPmounted in the stack. The initiatormay be disposed in the end capand may comprise a pair of electrical leadsto receive an electrical signal for actuation, in the present example embodiment one positive (+) lead and one negative (−) electrical lead. Upon application of an electrical actuation signal to the electrical leads, the initiatorproduces a localized ignition that in turn actuates the charge. The actuated chargepropels the shearing device (in) across the through bore(see). Such electrical signal may be provided to the electrical leadsby a cable. Once again referring to, the cablemay be linked to an interface moduledisposed on the BOP stack. The interface moduleis further described below.

A multiplex (MUX) cableof types known in the art may extend along the riserto provide a signal and data transfer channel between the floating platformand the BOP stack. The MUX cablemay also be used to provide electrical power to the BOP stackand to the interface modulefrom a power supply (not shown) on the floating platform. In some embodiments, the interface moduleand/or the BOP stackmay be provided with one or more batteries (e.g., as described with respect to) disposed at any convenient location on or about the BOP stackto provide local backup electrical power as may be needed. As described above, in the event it becomes necessary to actuate the kinetic BOPto close off the through bore (), an operator on the floating platformcan press the button on the control panel in (in communication with the controller), which causes the controllerto send an electrical signal to the interface modulealong the MUX cable. The interface modulein response sends an electrical signal to the initiatorvia the cableand the kinetic BOPis actuated. In some embodiments, the BOP stackmay be implemented with a local controller′ to provide the control functions described herein. For example, in some embodiments, the interface modulemay be configured with a controller′, as shown in. With such embodiments, an operator on the floating platformcan remotely provide activation signals to the controller′ via the control panel in communication with the controller.

In embodiments using hydraulically actuated BOPs, such as the example embodiment shown in, the BOP stackmay be provided with conventional valves, hoses, and related hardware to direct pressurized hydraulic fluid from accumulatorsto the BOP rams (not shown separately for clarity) as is known in the art. In some embodiments, accumulators may also be located on the floating platform(not shown). With such configurations, hydraulic fluid for the BOPscan either be directed from the surface-based accumulators and/or subsea accumulators. When an operator uses the control panel to actuate the surface-based and/or subsea accumulatorsusing the blue or yellow control pods (as described above atandwith reference to), a pressure sensor/transducercoupled into the hydraulic linesfeeding the fluid to the BOPrams detects pressure in the lines resulting from such operation and sends a corresponding signal to the interface moduleindicative of ram actuation pressure being present in the hydraulic lines. The interface moduledetects such pressure signal and may correspondingly send an electrical actuation signal to the initiator (in) using the cable, and the kinetic BOPis thereby actuated. In this way, the kinetic BOPmay be simultaneously actuated when any of the conventional BOPs are actuated while using only a single, hydraulic control signal from the floating platform.

In some embodiments, a fluid conduitmay extend between the shipand the BOP stackto provide a supply of hydraulic fluid to the BOP stack. Some embodiments of a BOP stack according to this disclosure may be implemented with a hydraulic fluid communication system, applying conventional fluid flow and/or pressure encoders/decoders known in the art, for example, fluid flow and/or pressure modulation devices used during well drilling and commonly referred to as “mud pulse” telemetry. In such embodiments, a fluid encoder(e.g., a fluid pressure or flow rate modulator such as a valve) disposed on the floating platformmay be linked in signal communication with the control paneland the hydraulic fluid conduit. When an operator operates the control panel to actuate any BOP,on the BOP stack, the encoderis activated to simultaneously send an actuation signal, e.g., in the form of pressure or flow rate changes along the hydraulic fluid conduit. At the BOP stackend of the hydraulic fluid conduit, a receiver(e.g., a pressure transducer) coupled into the hydraulic fluid conduitdetects the actuation signal and in turn conveys a corresponding signal (e.g., an electrical signal) to the interface module. When the interface moduledetects such electrical signal, the interface modulein turn sends an actuation (electrical) signal to the initiator (in) along the cable, and the kinetic BOPis thereby actuated.

Some embodiments of a BOP stackaccording to this disclosure may also be implemented with an acoustic communication system. In such embodiments, the shipmay be provided with a conventional marine acoustic communication transmitterin signal communication with the controller. When an operator uses the control panel (and correspondingly the controlleroperates) to actuate a BOP,on the BOP stack, the controllermay simultaneously operate the acoustic communication transmitterto send an acoustic signal to the BOP stackas is known in the art. At the BOP stack, an acoustic sensorreceives the acoustic signal and in turn conveys a corresponding signal to the interface module. When the interface moduledetects such corresponding signal, the interface modulethen sends an actuation (electrical) signal to the initiator (in) along the cable, and the kinetic BOPis thereby actuated.

Other embodiments may be implemented for actuating the kinetic BOPusing a conventional subsea remotely operated vehicle (ROV). The interface modulemay be provided with an actuation switch or buttonwired to send an actuation signal to the initiator (in) along the cablewhen so operated by the ROV. In some embodiments, the interface modulemay be implemented with a subsea receptacleconfigured to receive electrical power from the ROVthrough a telescoping arm on the ROV in any manner known in the art. Such embodiments may provide the actuation signal for the initiator (in) in the event no electrical power was available at the BOP stack, e.g., by failure of any local electrical power source and/or the cable.

shows another example embodiment of a BOP stackaccording to this disclosure. The BOP assembly includes stacked conventional BOP units, which as previously described, are generally configured with rams that are actuated by hydraulic fluid under pressure. A kinetic BOPis also included in the stack. All of the components are mounted on a frameconfigured for disposal underwater for coupling to a wellhead at the see floor. Although not shown for clarity of illustration in, it will be appreciated that embodiments of this BOP stackmay be implemented with any and all of the components and features described with respect to the other disclosed BOP stackembodiments for operation as disclosed herein.

The BOP stackembodiment ofdoes not entail the use of pressurized accumulators (e.g.,in) to operate the BOP unit(s). The BOP assembly is equipped with a unitary moduleconsisting of a variable displacement pump, a subsea motor, and variable frequency drive (VFD). The separate modulecomponents are coupled together to provide a compact unit. The variable displacement pumpin the moduleis fluidly coupled to a hydraulic fluid reservoiralso mounted on the BOP stack. A controller bottleis also linked to the moduleto house local electronics and processors for operational control of the system. One or more batteries may be housed in the controller bottleto power the system. A MUXcable may also be coupled to the BOP stackto provide power, data/signal communications, and/or fluid transfer from the floating platform. Some embodiments may include independent power linesto remotely recharge the batteries from the platform(e.g., to provide a trickle charge when the system is idle, to maintain a set charge). In some embodiments, electrical power may also be supplied to the batteries and/or the system via an ROV (e.g.,in) coupling into a receptacle (e.g.,in) on the interface module. In some embodiments, hydraulic fluid may also be provided to the reservoirvia the ROV. For clarity of illustration, not all conduits (e.g., hoses, cabling) are shown in.

As described herein, in the event it becomes necessary to actuate the kinetic BOPto close off the through bore (in), an operator on the floating platformcan press a button on a control panel to send an electrical signal to the interface modulealong the MUX cableor remotely provide an activation signal to the controller′. The interface modulein response can simultaneously send electrical signals to the initiatorvia the cable (e.g.,in) to actuate the kinetic BOPand to the moduleto activate the pumpto energize the rams on the BOPvia the hydraulic fluid from the reservoir. BOP stackembodiments may also be implemented for acoustic activation via the acoustic transmitter/sensor configurations described herein. In response to the acoustic signaling, the interface modulecan simultaneously send electrical signals to the initiatorto actuate the kinetic BOPand to the moduleto activate the pumpto energize the rams on the BOPs. Other embodiments may be implemented for simultaneously actuating the kinetic BOPand the pumpto energize the rams on the BOPsusing the ROV to actuate the switch or button (e.g.,in) on the interface module, which is wired to send the respective actuation signals. Elimination of the pressurized accumulator tanks significantly reduces the overall weight of the stackstructure (e.g., a reduction of approximately 200,000 lbs.) and reduces the likelihood of failure attributable to such underwater pressured systems. BP stackembodiments may be implemented with conventional pumpsrated to provide sufficient fluid pressure to rapidly actuate the conventional BOP units.

In some embodiments of the BOP stacks, the interface modulemay be programmed to automatically send an actuation (electrical) signal to the initiator (in) to actuate the kinetic BOPif a fail-safe event occurs (e.g., all power is out on the stack for a predetermined time period, accumulator pressure drops below a predetermined value, etc.). It will be appreciated by those skilled in the art that in some embodiments, the interface modulemay be implemented with batteries, electronics, and processors configured with instructions to perform as described herein using conventional software and electronics protocols. The controllermay be correspondingly implemented.

shows a cross-section view of another kinetic BOPaccording to an example embodiment of the present disclosure. The BOPis similar to the BOPshown in. However, this kinetic BOPis configured with multiple ports,,formed in the BOP walls for the mounting of pressure sensors (see) to detect and measure internal fluid pressures in specific areas of the BOP. A first portis formed on the BOPto provide a channel to the internal chamber of the end cap. A second portis formed on the BOPto provide a channel to the internal passageon the first side of the through bore. A third portis formed in the BOPto provide a channel to the internal passageon the second side of the through bore, in between the energy absorption mechanismand the closed end of the BOP.

Since the kinetic BOPsare routinely disposed under water for offshore operations, it is very important to determine if any water has breached the BOPto foul the internal chambers/passages. As shown in, the first portis formed on the BOPend capto permit a pressure sensor to detect and measure the internal chamber pressure where the initiatoris housed. If water or any other undesired substance contaminates the end caphousing, the initiatormay fail and/or the chargemay be compromised. The second portis formed in the BOPto permit a pressure sensor to detect and measure the internal pressure in the transverse passagein the path of the shearing device. Firing the chargeto propel the shearing devicewith any water contaminating the transverse passagecould be catastrophic due to the high gas pressures generated. The third portis formed in the BOPto permit a pressure sensor to detect and measure the internal pressure in the transverse passagein the path of the energy absorption mechanism.

shows the kinetic BOP ofin a stage after the initiatorhas been actuated and the chargehas ignited to propel the shearing devicealong the passageand across the through bore. Once the shearing devicepasses the through boreit impinges the energy absorption mechanism. The mechanismis configured to crush and slide within the passageon the second side of the through boreas it absorbs the kinetic energy of the shearing device. As shown in, the transverse passageon the second side of the through borehas a larger cross section than the passageon the first side of the through bore. If water or any other undesired substance contaminates the passageon the second side of the through bore, the energy absorption mechanismmay jam with catastrophic results.

shows a perspective view of an end capof a kinetic BOPembodiment of this disclosure. A pressure sensoris mounted on a side wall of the end cap. The sensorcan be securely affixed to the end capvia conventional means as known in the art (e.g., with mounting bolts).shows the exterior of the pressure sensor, with its housing and power/communication connectors. The sensoris mounted over the portformed in the side wall of the end cap(see). It will be understood that pressure sensorsare also mounted on the BOPwalls over the other ports,() formed in the side walls of the BOPto provide the respective channels to the internal passages. Conventional pressure sensors may be used with implementations of the kinetic BOPembodiments.

The pressure sensorsmounted over the ports,,can be configured to detect and monitor the respective internal pressures in the BOPas described herein. In some embodiments, the pressure sensorsare configured to signal when the respective internal pressure increases beyond a predetermined pressure parameter. For example, upon assembly the respective internal BOPchambers/passages are at a neutral or zero pressure. If water or another contaminant enters an internal chamber/passage, the pressure will increase, triggering the respective pressure sensorto indicate a pressure increase. The pressure sensorscan be configured to send a signal to the interface moduleupon detection of a pressure increase. Upon receipt of an increased pressure signal from a pressure sensor, the interface moduleis programmed to prevent an actuation signal from being sent to the initiator. In this manner, the kinetic BOPwill not be actuated if any of the pressure sensorsdetects an increase in the respective predefined (e.g. zero pressure) internal chamber/passage pressure parameter. It will be understood by those skilled in the art that the individual pressure sensorscan be set to emit a signal at different predetermined pressure parameter readings. In some embodiments, the pressure sensor(s)may be configured solely to monitor the respective internal chamber/passage pressure parameters for processing by the interface module. In this manner, an operator can remotely adjust the sensortrigger warning parameters as desired (e.g., to adjust for external pressure effects in deep water BOPdeployments). The pressure sensorsmay be linked to the system communication/power network as described herein and/or to conventional means as known in the art to provide signals to a remote location (e.g., warning signal to a remote work center if a pressure parameter deviation is detected).

Unlike conventional BOP systems that can receive only one actuation signal at a time due to the physical constraints imposed by the hydraulics of the systems, embodiments according to the present disclosure are capable of kinetic BOP actuation via multiple control signals, sent simultaneously or otherwise. Since the kinetic BOPis actuated by an electrical signal, it is not constrained as to the number of actuation signals it can receive. As soon as the interface modulereceives a triggering signal from among the various described modes and unless a pressure sensorhas triggered an increased pressure signal, the actuation signal is immediately applied to the initiator (in) and the kinetic BOPis thereby actuated. One mode or all such modes may be actuated at once to trigger the interface moduleto actuate the kinetic BOP. This provides for rapid wellbore control with greater reliability in the event a well shut off event occurs.

In light of the principles and example embodiments described and illustrated herein, it will be recognized that the example embodiments can be modified in arrangement and detail without departing from such principles. It will be appreciated by those skilled in the art that conventional hardware, electronics, and components may be used to implement the embodiments of this disclosure. Although only a few examples have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible within the scope of the described examples. Accordingly, all such modifications are intended to be included within the scope of this disclosure as defined in the following claims.