A dual mode cooperative hydraulic drive ram preventer and method of use

Abstract

The application relates to the field of well control equipment for oil and gas drilling, in particular to a double-mode cooperative hydraulic driving ram preventer and a use method. The double-mode cooperative hydraulic driving ram preventer comprises a shell, a shell cavity is arranged in the shell, the shell cavity is used for being connected with a well head, a ram is arranged in the shell cavity; a side door is used for closing the shell cavity; a liquid cylinder assembly and the side door form a first oil cavity; a first piston is inserted on the liquid cylinder assembly and the side door, the first piston is connected with the ram; a second piston is sleeved on the first piston, the second piston is provided with a second oil cavity, the first piston is connected with the second oil cavity, the second piston is arranged in the first oil cavity, and the outer wall of the second piston is in dynamic sealing connection with the inner wall of the first oil cavity. When the well is closed, the oil liquid first drives the first piston to act, the ram is moved to the center of the well head and closes the well head, then the second piston and the first piston are synchronously pushed, sealing is realized, and the well closing speed of the ram preventer is improved.

Description

Technical Field

[0001] This application relates to the field of well control equipment for oil and gas drilling, and in particular to a dual-mode cooperative hydraulically driven gate blowout preventer and its usage method. Background Technology

[0002] In oil and gas drilling operations, a blowout can occur when the formation pressure rises abnormally. A gate blowout preventer can quickly close the gate to seal the wellhead and prevent a blowout.

[0003] Existing hydraulically driven blowout preventers (BOPs) include a housing, side doors, a cylinder assembly, and a piston. The housing contains a cross-shaped housing cavity. One end of the vertical housing cavity is connected to the wellhead, and the other end is connected to another BOP or drill string. A gate is located within the horizontal housing cavity. Each end of the horizontal housing cavity is sealed to a side door, and the other end of each side door is sealed to the cylinder assembly. The cylinder assembly contains an oil chamber. The piston passes through the oil chamber and the side doors and connects to the gate. The side wall of the piston is sealed to the inner wall of the oil chamber, allowing the oil in the oil chamber to push the piston closer to or away from the housing cavity, thereby closing or opening the gate.

[0004] However, there is a problem with the slow shut-in speed when shutting in the well. Summary of the Invention

[0005] This application provides a dual-mode collaborative hydraulically driven gate blowout preventer and its usage method to solve the aforementioned technical problem of slow well shut-in speed.

[0006] In a first aspect, embodiments of this application provide a dual-mode cooperative hydraulically driven gate blowout preventer, comprising:

[0007] A housing, wherein a housing cavity is provided within the housing for connection with a wellhead, and a gate is provided within the housing cavity;

[0008] A side door, which is connected to the housing, is used to close the housing cavity;

[0009] A hydraulic cylinder assembly, which is connected to the side door, and the hydraulic cylinder assembly and the side door form a first oil chamber;

[0010] A first piston is inserted into the hydraulic cylinder assembly and the side door. The hydraulic cylinder assembly and the side door are both dynamically sealed to the first piston. The first piston is connected to the gate.

[0011] The second piston is sleeved on the first piston. The second piston is provided with a second oil chamber. The first piston is connected to the second oil chamber. The second piston is disposed in the first oil chamber. The second piston divides the first oil chamber into a first sub-oil chamber and a second sub-oil chamber. The outer wall of the second piston is dynamically sealed to the inner wall of the first oil chamber.

[0012] The first piston is configured to move toward the housing cavity under the influence of oil entering the second oil chamber, so as to close the wellhead with the gate.

[0013] The second piston is configured to move simultaneously with the first piston under the influence of the oil entering the second sub-oil chamber, so as to drive the gate to close the wellhead.

[0014] In one possible embodiment, the second piston is provided with an overflow valve, which is configured to open when the oil pressure in the second oil chamber is greater than or equal to a preset value, so as to connect the second oil chamber and the second sub-oil chamber, so as to move the second piston and push the first piston toward the housing cavity;

[0015] And / or, the second piston is also provided with a one-way valve, so that when the oil in the first sub-oil chamber pushes the first piston and the second piston to move away from the housing cavity, the oil in the second sub-oil chamber enters the second oil chamber through the one-way valve.

[0016] In one possible embodiment, a third oil chamber is provided inside the hydraulic cylinder assembly, and the end of the first piston away from the housing is sealed to the hydraulic cylinder assembly, with the first piston portion located inside the third oil chamber;

[0017] The third oil chamber is configured to communicate with the second oil chamber when oil is introduced into the third oil chamber, so that the oil can enter the second oil chamber.

[0018] The third oil chamber is also configured to communicate with the second oil chamber when oil is introduced into the first sub-oil chamber to push the second piston to move, so that oil enters the third oil chamber.

[0019] In one possible embodiment, the first piston includes a piston rod and a piston body disposed on the piston rod. One end of the piston rod is connected to the gate, and the other end of the piston rod is sealed to the hydraulic cylinder assembly. The piston body is dynamically sealed to the inner wall of the second piston, and the end of the piston body facing away from the housing forms the second oil chamber with the inner wall of the second piston.

[0020] In one possible embodiment, an oil passage is provided inside the piston rod, the oil passage connecting the third oil chamber and the second oil chamber;

[0021] And / or, the piston rod is provided with a mounting part, the mounting part being used to mount the gate.

[0022] In one possible embodiment, the hydraulic cylinder assembly is further provided with a first oil hole communicating with the third oil chamber, the first oil hole being used to supply oil to enter and exit the third oil chamber;

[0023] And / or, the side door is provided with a second oil hole that communicates with the first sub-oil chamber, the second oil hole being used to supply oil to enter and exit the first sub-oil chamber.

[0024] In one possible embodiment, a through hole is provided on the side door, the through hole corresponding to the housing cavity, and the first piston passes through the through hole on the side door, with the through hole being dynamically sealed to the first piston.

[0025] In one possible embodiment, a plurality of first connectors are also included, the first connectors being used to connect the side door and the housing;

[0026] And / or, it also includes a plurality of second connectors for connecting the side door and the hydraulic cylinder assembly.

[0027] Secondly, embodiments of this application provide a method for using a dual-mode cooperative hydraulically driven gate blowout preventer, including the aforementioned dual-mode cooperative hydraulically driven gate blowout preventer, the method comprising:

[0028] The housing of the dual-mode collaborative hydraulically driven gate blowout preventer is connected to the wellhead of the drilled well, such that the housing cavity of the housing corresponds to the wellhead;

[0029] When the well pressure in the drilling is less than a preset value, oil is injected into the second oil chamber of the hydraulic cylinder assembly in the dual-mode coordinated hydraulic drive gate blowout preventer. The oil in the second oil chamber pushes the first piston of the dual-mode coordinated hydraulic drive gate blowout preventer toward the housing, so that the gate connected to the first piston is connected to the drill string in the housing cavity or to another gate.

[0030] Oil is continuously injected into the second oil chamber. The oil enters the second sub-oil chamber. The oil in the second sub-oil chamber of the dual-mode coordinated hydraulic drive gate blowout preventer pushes the second piston of the dual-mode coordinated hydraulic drive gate blowout preventer to drive the first piston toward the housing cavity, so as to drive the gate to close the wellhead.

[0031] When the well pressure in the well is greater than or equal to a preset value, oil is injected into the second oil chamber. The oil flows directly into the second sub-oil chamber. The oil in the second sub-oil chamber pushes the second piston and the first piston to move simultaneously, thereby driving the gate to close the wellhead.

[0032] In one possible embodiment, it also includes:

[0033] Oil is injected into the first sub-oil chamber of the dual-mode coordinated hydraulically driven gate blowout preventer. The oil pushes the first piston and the second piston to move simultaneously away from the housing cavity, so that the gate is disengaged from the drill string or the other gate in the housing cavity.

[0034] This application provides a dual-mode collaborative hydraulically driven gate blowout preventer and its usage method, comprising a housing, a side door, a hydraulic cylinder assembly, a first piston, and a second piston. The housing contains a housing cavity for connection to a wellhead, and the gate is disposed within the housing cavity. One end of the side door is connected to the housing to seal the housing cavity, and the other end is connected to the hydraulic cylinder assembly, forming a first oil chamber. The first piston is inserted into the hydraulic cylinder assembly and the side door, and is connected to the gate. The second piston has a second oil chamber, is sleeved on the first piston, and is disposed within the first oil chamber, dividing the first oil chamber into a first sub-oil chamber and a second sub-oil chamber. The second oil chamber is sealed to the first piston, and the outer wall of the second piston is sealed to the first oil chamber. The second piston can move relative to either the first piston or the first oil chamber.

[0035] The first piston can move towards the shell cavity under the action of the oil in the second oil chamber, so that the gate can be connected to the drill string in the shell cavity. In the initial stage of well shut-in, the first piston drives the gate to move quickly to the well shut-in position of the gate, so as to achieve rapid well shut-in. The second piston can move simultaneously with the first piston under the action of the oil in the second sub-oil chamber to drive the gate to seal the wellhead. At this time, the first piston is simultaneously subjected to the thrust of the oil in the second oil chamber and the thrust of the second piston, which increases the sealing thrust of the gate. This application takes into account both well shut-in speed and sealing thrust under limited hydraulic conditions, and improves the well shut-in speed and sealing thrust of the gate blowout preventer. Attached Figure Description

[0036] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0037] Figure 1 A schematic cross-sectional view of the initial state of the dual-mode collaborative hydraulically driven gate blowout preventer provided in this application during well shut-in;

[0038] Figure 2This is a schematic cross-sectional view of the initial state of the dual-mode collaborative hydraulically driven gate blowout preventer during well opening provided in this embodiment;

[0039] Figure 3 for Figure 2 A cross-sectional view of the first piston in the middle;

[0040] Figure 4 for Figure 2 Cross-sectional schematic diagram of the intermediate hydraulic cylinder assembly;

[0041] Figure 5 for Figure 2 A cross-sectional schematic diagram of the second piston in the middle;

[0042] Figure 6 for Figure 2 Schematic diagram of the center side door;

[0043] Figure 7 for Figure 6 A cross-sectional view from another direction;

[0044] Figure 8 for Figure 2 Schematic diagram of the middle shell;

[0045] Figure 9 This is an assembly diagram of the dual-mode collaborative hydraulically driven gate blowout preventer provided in this embodiment.

[0046] Explanation of reference numerals in the attached figures:

[0047] 100 - Shell; 110 - Shell cavity;

[0048] 200 - Side door; 210 - Second oil hole; 220 - Through hole;

[0049] 300 - Hydraulic cylinder assembly; 310 - First oil chamber; 311 - First sub-oil chamber; 312 - Second sub-oil chamber;

[0050] 320 - Third oil chamber; 330 - First oil hole;

[0051] 400 - First piston; 410 - Piston rod; 411 - Oil passage; 412 - Mounting part; 420 - Piston body;

[0052] 500 - Second piston; 510 - Second oil chamber; 520 - Relief valve; 530 - Check valve;

[0053] 600 - First connector; 610 - Second connector.

[0054] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0056] In the embodiments of this application, the terms "upper," "lower," "inner," "middle," "outer," "front," and "rear," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for better description of this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation. Furthermore, some of the above terms may be used to indicate other meanings besides orientation or positional relationship; for example, the term "upper" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in the embodiments of this application according to the specific circumstances.

[0057] Furthermore, the terms "set up," "connect," and "fix" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this disclosure according to the specific circumstances.

[0058] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a particular order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented, for example, in a sequence other than those illustrated or described herein.

[0059] In this application, the terms "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0060] Unless otherwise stated, the term "multiple" means two or more.

[0061] In oil and gas drilling operations, a blowout can occur when the formation pressure rises abnormally. A gate blowout preventer can quickly close the gate to seal the wellhead and prevent a blowout.

[0062] The gate blowout preventer is installed above the wellhead device. The shell has a cavity inside for the drill string to pass through. Side doors and hydraulic cylinder assemblies are set on both sides of the shell. The hydraulic drive mechanism is linked with the gate to isolate the wellbore in case of normal drilling, tripping, or wellhead abnormalities.

[0063] Existing gate blowout preventers (BOPs) consist of a housing, side doors, a hydraulic cylinder assembly, and a piston. The housing contains a cross-shaped cavity; one end of the vertical cavity connects to the wellhead, and the other end connects to another BOP or drill string. The gate is located within the horizontal cavity, with a side door sealed to each end. The other end of each side door is sealed to the hydraulic cylinder assembly. The hydraulic cylinder assembly contains an oil chamber. The piston passes through the oil chamber and the side doors and connects to the gate. The piston's sidewall is sealed to the inner wall of the oil chamber, allowing the hydraulic fluid in the chamber to push the piston closer to or further away from the housing cavity, thus closing or opening the gate. However, during shut-in, the piston's pressure-bearing area is limited, resulting in a slow shut-in speed under limited hydraulic pressure conditions.

[0064] The gate blowout preventer provided in this application adopts a structure consisting of a shell, a side door, a hydraulic cylinder assembly, and a first piston connected to the gate and a second piston sleeved on the first piston. The shell has an internal cavity, and the gate is located within this cavity. The cavity is used to connect to the wellhead. The hydraulic cylinder assembly and the side door form a first oil chamber, and the second piston is located in a second oil chamber. The first piston and the second oil chamber are dynamically sealed together. The first piston moves towards the shell cavity under the influence of the oil entering the second oil chamber, connecting the gate to the drill string within the shell cavity. In the initial stage of well shut-in, the first piston drives the gate to quickly move to the shut-in position, achieving rapid well shut-in. The second piston can move simultaneously with the first piston under the influence of the oil in the second oil chamber to drive the gate to seal the wellhead. At this time, the first piston is simultaneously subjected to the thrust of the oil in the second oil chamber and the thrust of the second piston, increasing the sealing thrust of the gate. This application balances shut-in speed and sealing thrust under limited hydraulic conditions, improving both the shut-in speed and sealing thrust of the gate blowout preventer.

[0065] Reference Figures 1 to 9 As shown, this application embodiment provides a dual-mode collaborative hydraulically driven gate blowout preventer, including a housing 100, a housing cavity 110 disposed within the housing 100 for connection to a wellhead, and a gate disposed within the housing cavity 110; a side door 200 connected to the housing 100 for sealing the housing cavity 110; and a hydraulic cylinder assembly 300 connected to the side door 200, the hydraulic cylinder assembly 300 and the side door 200 forming a first oil chamber 310.

[0066] A first piston 400 is inserted into the hydraulic cylinder assembly 300 and the side door 200. The hydraulic cylinder assembly 300 and the side door 200 are dynamically sealed to the first piston 400. The first piston 400 is connected to the gate. A second piston 500 is sleeved on the first piston 400. The second piston 500 is provided with a second oil chamber 510. The first piston 400 is connected to the second oil chamber 510. The second piston 500 is located inside the first oil chamber 310. The second piston 500 divides the first oil chamber 310 into a first sub-oil chamber 311 and a second sub-oil chamber 312. The outer wall of the second piston 500 is dynamically sealed to the inner wall of the first oil chamber 310.

[0067] The first piston 400 is configured to move toward the housing cavity 110 under the influence of the oil entering the second oil chamber 510, so as to close the wellhead with the gate; the second piston 500 is configured to move simultaneously with the first piston 400 under the influence of the oil entering the second sub-oil chamber 312, so as to drive the gate to close the wellhead.

[0068] The housing 100 is a closed housing structure that forms the main supporting frame of the gate blowout preventer. It is used to form a housing cavity 110 that communicates with the wellhead and to provide installation, guidance and force support for the internal gate. The housing 100 is usually set on the outer periphery of the device and serves as the mounting base for the side door 200, the hydraulic cylinder assembly 300 and related connecting parts. The housing cavity 110 is arranged coaxially or nearly coaxially with the wellhead device to ensure that the gate can seal the wellhead.

[0069] In one possible embodiment, the housing 100 can be an integral cast box, a welded combined box, or a forged integral housing. A cross-shaped through-cavity can be provided inside the housing 100. A stepped mounting surface or reinforcing rib structure can be correspondingly provided on the end of the housing 100 that connects to the wellhead. The other end of the housing 100 connects to another gate blowout preventer or to the drill string. The housing 100 can be made of high-strength alloy steel, low-alloy high-strength steel, or corrosion-resistant metal composite materials, and a high stiffness ratio is maintained between the wall thickness and the internal cavity dimensions to adapt to high-pressure wellhead conditions.

[0070] The shell cavity 110 is a working space enclosed inside the shell 100 to accommodate the gate and communicate with the wellhead. It provides a passage for the drill string inside the wellbore and forms a closed sealing interface when the well is shut in. The shell cavity 110 is located in the middle of the shell 100 and corresponds to and cooperates with the side door 200 and the hydraulic cylinder assembly 300 so that the gate can enter or exit the shell cavity 110 under the driving action of the first piston 400.

[0071] In an exemplary implementation, the housing cavity 110 may be a cross-shaped through-channel, with the vertical cavity used to connect the wellhead and accommodate the drill string, and the horizontal cavity used to accommodate the gate. The effective inner diameter or inner width of the housing cavity 110 must be greater than the maximum outer diameter of the drill string and reserve space for the full stroke of the gate and the sealing compression.

[0072] The gate can be a sealing component that can reciprocate within the housing cavity 110 and is used to close the wellhead or cover the drill string. The gate is used to form a pressure barrier when the blowout preventer is shut in, thereby preventing fluid leakage from the well. The gate is disposed within the housing cavity 110 and is fixedly or detachably connected to the first piston 400, and moves into the closed position with the linear movement of the first piston 400.

[0073] In one possible embodiment, the gate can be a shear type, a semi-sealed type, or a fully sealed type. The gate cross-section can be wedge-shaped, rectangular with bevels, or an arc-shaped envelope structure. The gate material can be high-strength alloy steel, surface overlay with wear-resistant and corrosion-resistant layer, or a composite structure with hard alloy blades. The width of the gate matches the width of the housing cavity 110, and the thickness is sufficient to withstand the well shut-in thrust and ensure complete contact of the sealing surface.

[0074] The side door 200 can be a door structure that is detachably and sealingly connected to the housing 100 and used to close the lateral opening of the housing cavity 110. The side door 200 is used to form the installation space of the hydraulic cylinder assembly 300 and to provide guidance for the first piston 400. At the same time, the side door 200 and the housing 100 together form a closed working space. The side door 200 is usually located on the side of the housing 100 and connected to the housing 100. The inner side of the side door 200 at the opposite end of the housing 100 cooperates with the hydraulic cylinder assembly 300 to form the first oil cavity 310.

[0075] In one possible embodiment, the side door 200 may be a flat, boss-type, or cavity-type door cover structure. The side door 200 may be made of high-strength steel castings, forgings, or welded parts. Both surfaces connected to the housing 100 and the hydraulic cylinder assembly 300 may be provided with sealing grooves. The thickness and flange width of the side door 200 meet the pressure-bearing connection requirements with the housing 100. The width of the sealing surface matches the cross-sectional dimensions of the sealing ring to form a reliable clamping.

[0076] The cylinder assembly 300 can be a hydraulic actuator for housing and driving piston movement. The cylinder assembly 300 is used to convert hydraulic oil pressure into linear thrust and achieves coordinated driving through a first oil chamber 310 formed together with the side door 200. The cylinder assembly 300 is connected to the side door 200 and located on the side of the housing 100.

[0077] In one possible embodiment, the cylinder assembly 300 may be an integral cylinder, a split-combination cylinder, or a cylinder liner structure. The outer shell material of the cylinder assembly 300 may be high-strength alloy steel, wear-resistant alloy steel, or surface-hardened steel. The inner diameter of the first oil chamber 310 and the outer diameter of the piston form a small clearance sliding fit. The length of the cylinder assembly 300 covers the entire stroke of the first piston 400 and reserves a sealing compression amount.

[0078] The first piston 400 can be a linear motion component inserted into the hydraulic cylinder assembly 300 and the side door 200. The end of the first piston 400 near the housing cavity 110 is connected to the gate. The first piston 400 is used to move towards the housing cavity 110 under the push of the oil in the second oil chamber 510 and drive the gate to move. The first piston 400 is dynamically sealed with the hydraulic cylinder assembly 300 and the side door 200, so that the gate is pushed from the open state to the closed state under the action of hydraulic pressure, thereby realizing the opening and closing of the wellhead.

[0079] The first piston 400 passes through the side door 200 and forms a fit with the inner wall of the second piston 500. In one possible embodiment, the first piston 400 can be a stepped shaft type, a cylindrical shaft type, or a combined structure with a head step. The material of the first piston 400 can be high-strength alloy steel, surface hardened steel, or wear-resistant stainless steel. The outer circular surface of the first piston 400 can be provided with a sealing groove, a guide groove, or a wear-resistant coating. The effective pressure area of ​​the first piston 400 needs to be sufficient to generate sufficient initial pushing force, and the stroke covers the distance from the gate plate from the starting position to the pre-contact drill rod position or another gate plate.

[0080] The second piston 500 can be an outer sleeve piston component fitted on the first piston 400. The second piston 500 is used to divide the first oil chamber 310 into a first sub-oil chamber 311 and a second sub-oil chamber 312. Under the action of the oil in the second sub-oil chamber 312, it moves synchronously with the first piston 400 to drive the gate to close the wellhead. The second piston 500 is coaxially arranged with the first piston 400 and its outer wall is dynamically sealed to the inner wall of the first oil chamber 310. At the same time, the interior of the second piston 500 and the first piston 400 form the second oil chamber 510.

[0081] In one possible embodiment, the second piston 500 may be an annular sleeve type, a stepped sleeve type, or a built-in valve cavity type structure. The material of the second piston 500 may be high-strength alloy steel, wear-resistant steel, or surface-treated metal. A sealing ring groove may be provided on the outer wall of the second piston 500. The outer diameter of the second piston 500 and the inner diameter of the first oil cavity 310 are in a dynamic seal or small clearance sliding fit. The size of the second oil cavity 510 and the outer diameter of the first piston 400 are in a sealed sliding fit.

[0082] The second oil chamber 510 is an internal hydraulic space enclosed by the first piston 400 and the second piston 500. It is used to receive oil and, under pressure, push the first piston 400 toward the housing cavity 110. The second oil chamber 510 is located inside the second piston 500 or within the enclosed area enclosed by the two pistons. In one possible embodiment, the second oil chamber 510 is a sealed cavity, and its volume is smaller than that of the first oil chamber 310 to facilitate rapid pressurization and response.

[0083] The oil entering the second oil chamber 510 and the oil entering the second sub-oil chamber 312 can be mineral hydraulic oil, synthetic hydraulic oil or flame-retardant hydraulic medium.

[0084] Based on the above analysis, it can be seen that the dual-mode cooperative hydraulically driven gate blowout preventer provided in this application embodiment, during operation, the oil first enters the second oil chamber 510 and generates thrust on the first piston 400. Under the action of the thrust, the first piston 400 moves towards the housing cavity 110, thereby driving the gate connected to the first piston 400 to approach the wellhead center along a predetermined trajectory within the housing cavity 110, achieving approach and pre-positioning of the drill string. In the initial stage of well shut-in, the first piston 400 drives the gate to quickly move to the well shut-in position of the gate, achieving rapid well shut-in; the oil in the second oil chamber 510 flows into the second sub-oil chamber 312, thereby... The second piston 500 drives the first piston 400 to continue moving towards the housing cavity 110, providing thrust for the first piston 400 to seal the wellhead. At this time, the first piston 400 is simultaneously subjected to the thrust of the oil in the second oil cavity 510 and the thrust of the second piston 500, increasing the sealing thrust of the gate valve. The first piston 400 undertakes the initial rapid propulsion function, while the second piston 500 provides supplementary drive and pressure maintenance capabilities after pressure is established. Thus, under limited hydraulic conditions, both response speed and sealing thrust are balanced, improving the stability, repeatability, and field adaptability of well control actions, and increasing the shut-in speed and sealing thrust of the gate valve blowout preventer. It should be understood that the above example is merely illustrative and not limiting. Any modifications using the same or equivalent technical means as this embodiment should fall within the protection scope of this application.

[0085] Reference Figure 5As shown, in one possible implementation, the second piston 500 is provided with an overflow valve 520, which is configured to open when the oil pressure in the second oil chamber 510 is greater than or equal to a preset value, so as to connect the second oil chamber 510 and the second sub-oil chamber 312, so that the second piston 500 moves and pushes the first piston 400 toward the housing cavity 110; and / or, the second piston 500 is also provided with a one-way valve 530, so that when the oil in the first sub-oil chamber 311 pushes the first piston 400 and the second piston 500 to move away from the housing cavity 110, the oil in the second sub-oil chamber 312 enters the second oil chamber 510 through the one-way valve 530.

[0086] In one possible embodiment, the overflow valve 520 can be a pressure-triggered valve structure disposed on the end face of the second piston 500 away from the housing 100. The overflow valve 520 is used to automatically open after the pressure in the second oil chamber 510 reaches a preset threshold, thereby connecting the second oil chamber 510 with the second sub-oil chamber 312 so that the oil in the second oil chamber 510 flows into the second sub-oil chamber 312. Driven by the oil in the second sub-oil chamber 312, the second piston 500 drives the first piston 400 to move towards the housing cavity 110. The overflow valve 520 can be arranged in the valve hole or embedded channel of the second piston 500. After the overflow valve 520 is opened, the oil can establish pressure balance and flow transmission through both sides of the second piston 500.

[0087] The relief valve 520 can be any of the following structures: spring cone valve, slide valve, ball valve, or pilot valve. The preset value of the relief valve 520 can be higher than the initial shut-in pressure. That is, when the gate has not reached the drill string position (initial shut-in), the relief valve 520 is always closed, so that the first piston 400 can drive the gate to move quickly to the shut-in position to achieve rapid shut-in. After the relief valve 520 is opened, the first piston 400 is simultaneously pushed by the second oil chamber 510 and the second piston 500, which increases the sealing thrust and improves the sealing reliability of the gate.

[0088] The one-way valve 530 can be a check valve installed on the second piston 500. The function of the one-way valve 530 is to allow the oil in the second sub-oil chamber 312 to flow into the second oil chamber 510 through the one-way valve 530 when the oil in the first sub-oil chamber 311 pushes the first piston 400 and the second piston 500 to move away from the housing chamber 110, thereby establishing a one-way oil replenishment path and preventing the oil from flowing back in reverse during the piston reset or well opening stage.

[0089] The one-way valve 530 can be any of the following types: ball check valve, cone check valve, plate check valve, or diaphragm check valve. The installation orientation of the one-way valve 530 is such that it only allows the oil in the second sub-oil chamber 312 to flow unidirectionally to the second oil chamber 510. In other words, the one-way valve 530 is closed when the first piston 400 moves toward the housing chamber 110 (well shut-off), preventing the oil from flowing backward during the process of the first piston 400 moving toward the housing chamber 110.

[0090] Based on the above structure, when the system is started and enters the well shut-in operation, the oil enters the second oil chamber 510. Driven by the oil, the first piston 400 moves towards the shell cavity 110. In the initial stage, the oil in the second oil chamber 510 provides the driving force, causing the gate to quickly move towards the center of the wellhead, realizing a rapid well shut-in operation. After the gate is connected to the drill string or another gate, the drill string or gate has a counter-thrust force on the first piston 400. At this time, the pressure in the second oil chamber 510 rises accordingly. When the pressure reaches the preset value of the overflow valve 520, the overflow valve 520 automatically opens, and the second oil chamber 510 is connected to the second sub-oil chamber 312. The oil flows from the second oil chamber 510 to the second sub-oil chamber 312 through the overflow valve 520. The oil in the second sub-oil chamber 312 pushes the second piston 500 to drive the first piston 400 to move towards the shell cavity 110, ultimately improving the continuous thrust and sealing pressure during the gate closing stage.

[0091] It is worth mentioning that when the wellhead pressure is too high, oil is injected into the second oil chamber 510. In the initial stage of the first piston 400's movement, the wellhead pressure prevents the first piston 400 from moving towards the shell cavity 110, causing the oil pressure in the second oil chamber 510 to rise rapidly. The oil pressure reaches the preset value of the relief valve 520 in an instant. At this time, the oil can enter the second sub-oil chamber 312 from the second oil chamber 510 in a short time. The oil in the second sub-oil chamber 312 pushes the first piston 400 and the second piston 500 to move towards the shell cavity 110 at the same time, which speeds up the start-up speed of the first piston 400 and the second piston 500, thus speeding up the shut-in speed.

[0092] Accordingly, during the process of reverse reset or well opening, the oil in the first sub-oil chamber 311 pushes the first piston 400 and the second piston 500 away from the casing chamber 110. Under the influence of pressure differential, the oil in the second sub-oil chamber 312 enters the second oil chamber 510 through the one-way valve 530, allowing the piston assembly to smoothly return to its initial position. Thus, the one-way valve 530 achieves unidirectional conduction during the reset phase, reducing response lag during well shut-in. It should be understood that the above example is merely illustrative and not limiting.

[0093] Reference Figure 2 and Figure 4As shown, based on the aforementioned embodiment, a third oil chamber 320 is further provided in the hydraulic cylinder assembly 300. The end of the first piston 400 away from the housing 100 is sealed and connected to the hydraulic cylinder assembly 300, and part of the first piston 400 is located in the third oil chamber 320. The third oil chamber 320 is configured to communicate with the second oil chamber 510 when oil is introduced into the third oil chamber 320, so that the oil enters the second oil chamber 510. The third oil chamber 320 is also configured to communicate with the second oil chamber 510 when oil is introduced into the first sub-oil chamber 311 to push the second piston 500 to move, so that the oil enters the third oil chamber 320.

[0094] In one possible embodiment, the third oil chamber 320 is an independent hydraulic cavity provided inside the cylinder assembly 300, used to realize the temporary storage, conduction and return of oil during the coordinated action of the first piston 400 and the second piston 500. The third oil chamber 320 constitutes an auxiliary working chamber that cooperates with the second oil chamber 510.

[0095] The third oil chamber 320 allows the first piston 400 to obtain stable hydraulic support when under pressure, forming different pressure transmission paths under different well shut-in or well opening conditions, thus enabling the hydraulic drive process to balance action response and thrust maintenance. The third oil chamber 320 can be located inside the cylinder assembly 300 on the side opposite to the housing 100, and together with the end of the first piston 400 opposite to the housing 100, it defines the pressure-bearing space. The first piston 400 forms a sliding seal with the housing of the cylinder assembly 300 that forms the third oil chamber 320 through a sealing element, so as to avoid oil leakage and ensure that the pressure is effectively applied to the end face of the first piston 400.

[0096] The third oil chamber 320 can be any of the following: an annular chamber, a stepped chamber, or a cylindrical chamber. The end of the first piston 400 facing away from the housing 100 is sealed to the cylinder assembly 300. A circumferential sealing ring, end face seal, or lip seal structure is provided between the first piston 400 and the cylinder assembly 300 to maintain controllable pressure within the third oil chamber 320 during the axial reciprocating motion of the first piston 400, preventing pressure loss from affecting the gate closing speed and sealing force. A portion of the first piston 400 is located within the third oil chamber 320. This portion can be a cylindrical section, a stepped section, or a section with a guide ring, bearing pressure while also providing axial guidance to prevent piston wobble and sealing failure.

[0097] When oil is introduced into the third oil chamber 320, it connects with the second oil chamber 510 to allow oil to enter the second oil chamber 510. In the oil circuit design, a connecting channel is provided between the third oil chamber 320 and the second oil chamber 510. The connecting channel can be an internal oil hole of the first piston 400, an external bypass oil passage 411, an annular connecting groove, or a channel structure controlled by a valve. When an external hydraulic source supplies oil to the third oil chamber 320, the oil enters the second oil chamber 510 through this connecting channel, thereby generating a driving force in the second oil chamber 510, pushing the first piston 400 to move towards the housing cavity 110, and driving the gate connected to the first piston 400 into a well-sealing or near-well-sealing state.

[0098] When oil is introduced into the first sub-oil chamber 311 to push the second piston 500 and the first piston 400 to move, it communicates with the second oil chamber 510 so that the oil enters the third oil chamber 320. When the second piston 500 and the first piston 400 move away from the housing 100 driven by the pressure of the first sub-oil chamber 311, the oil in the second oil chamber 510 can return to the third oil chamber 320 through the same or another communication path to achieve pressure balance, volume compensation or return oil replenishment.

[0099] By configuring the third oil chamber 320 as a functional chamber that combines oil supply and return flow balancing, a hydraulic synergy can be formed between the first piston 400 and the second piston 500. During the initial shut-in phase, oil can be rapidly supplied to the second oil chamber 510 via the third oil chamber 320 to enhance responsiveness. During well opening, oil can enter the third oil chamber 320 via the connecting return flow driven by the first sub-oil chamber 311, thereby reducing the impact of pressure surges and flow resistance on piston movement. This allows the second oil chamber 510 to share the same oil path for oil inlet pressurization and oil return depressurization. It should be understood that the above example is for demonstration purposes only and is not limiting.

[0100] Reference Figure 1 and Figure 3 As shown, in one possible implementation, the first piston 400 includes a piston rod 410 and a piston body 420 disposed on the piston rod 410. One end of the piston rod 410 is connected to a gate, and the other end of the piston rod 410 is sealed to the hydraulic cylinder assembly 300. The piston body 420 is dynamically sealed to the inner wall of the second piston 500. The end of the piston body 420 away from the housing 100 and the inner wall of the second piston 500 form a second oil chamber 510.

[0101] In this application, the first piston 400 is composed of a piston rod 410 and a piston body 420 disposed on the piston rod 410. The piston rod 410 is used to transmit displacement and thrust, and the piston body 420 is used to form a pressure fit with the second piston 500 and to define the working space of the second oil chamber 510. The two can be made into an integral structure or a detachable and combinable structure, so as to be replaced or repaired according to assembly and maintenance needs.

[0102] One end of the piston rod 410 is connected to the gate, and the other end is sealed to the hydraulic cylinder assembly 300, so that the first piston 400 can move stably along the axial direction of the hydraulic cylinder assembly 300 when under pressure, and directly transmit the axial thrust to the gate, thereby realizing the opening, closing and sealing action of the gate; the piston body 420 is dynamically sealed to the inner wall of the second piston 500, which can maintain pressure isolation between adjacent chambers during the reciprocating motion of the first piston 400 and reduce high-pressure oil leakage; the end of the piston body 420 away from the housing 100 and the inner wall of the second piston 500 form a second oil chamber 510, so that the second oil chamber 510 becomes the working space between the first piston 400 and the second piston 500 for pressure driving and pressure transmission.

[0103] The piston rod 410 passes through the side door 200 and the hydraulic cylinder assembly 300. The piston body 420 is set on the piston rod 410 and located inside the second piston 500 or in the overlapping area that cooperates with the second oil chamber 510. The piston rod 410 and the gate can reliably transmit force through threaded connection, pin connection or flange connection. Locking parts or anti-loosening structures are provided at the connection to adapt to the vibration load under well control conditions.

[0104] The piston rod 410 can be a solid round rod, a hollow round rod, or a stepped rod. The piston body 420 can be a disc-shaped, cylindrical, or stepped structure with a sealing groove. The diameter of the piston rod 410 is smaller than the outer diameter of the piston body 420. A clearance fit is maintained between the rod diameter and the third oil chamber 320 to ensure smooth sliding while limiting wobbling. The axial thickness and pressure-bearing area of ​​the piston body 420 are designed to match the required shut-in thrust, system oil pressure, and stroke requirements. The length of the piston rod 410 should cover the assembly span from the cylinder assembly 300 to the gate. The axial length and radial clearance of the second oil chamber 510 should meet the balance requirements of oil filling and discharging rate and sealing reliability. It should be understood that the above examples are for illustrative purposes only and are not limiting.

[0105] When the system starts, hydraulic oil enters the second oil chamber 510 from the third oil chamber 320, acting on the pressure-bearing surface of the piston body 420 on the side opposite to the housing 100. Due to the stable dynamic seal between the piston body 420 and the inner wall of the second piston 500, the oil pushes the first piston 400 to move along the axis of the hydraulic cylinder assembly 300 towards the housing cavity 110. At the same time, the piston rod 410 advances linearly synchronously with the piston body 420, and one end of the piston rod 410 transmits the thrust to the gate, causing the gate to contact or clamp the drill string inside the housing cavity 110. This improves the response speed during the initial well shut-in phase.

[0106] The sealing structure between the piston rod 410 and the hydraulic cylinder assembly 300 is used to prevent high-pressure oil from leaking along the outer circumference of the rod, ensuring stable transmission of driving pressure; the dynamic seal between the piston body 420 and the inner wall of the second piston 500 ensures that the second oil chamber 510 maintains effective working pressure during operation, avoiding insufficient thrust due to excessive pressure decay. It should be understood that the above example is for demonstration purposes only and is not limiting.

[0107] Reference Figure 1 and Figure 3 As shown, based on the aforementioned embodiment, an oil passage 411 is further provided inside the piston rod 410, and the oil passage 411 connects the third oil chamber 320 and the second oil chamber 510. And / or, a mounting portion 412 is provided on the piston rod 410, and the mounting portion 412 is used to mount the gate.

[0108] In this application, the oil passage 411 can be a flow channel structure formed inside the piston rod 410 of the first piston 400 for conveying hydraulic medium. The oil passage 411 is used to connect the third oil chamber 320 and the second oil chamber 510, so that the oil can flow directionally between different oil chambers inside the piston rod 410 to meet the needs of oil supply, oil return and pressure balance. The oil passage 411 can be located in the axial central region of the piston rod 410, or it can be set as an eccentric channel, parallel multi-channel or branch channel according to the processing and layout needs, and form a fluid communication relationship with the third oil chamber 320 and the second oil chamber 510 through the openings, side orifices or interfaces connected to valves at both ends of the piston rod 410.

[0109] In one possible embodiment, the oil passage 411 may take the form of a straight passage, a stepped passage, a spiral passage, or a multi-hole parallel passage, in order to adapt to different flow requirements and pressure loss requirements.

[0110] The mounting part 412 can be a dedicated connection structure formed at the part of the piston rod 410 used to connect the gate plate. The mounting part 412 is used to realize reliable assembly between the gate plate and the piston rod 410 and to stably transmit the axial displacement of the piston rod 410 to the gate plate. The mounting part 412 can be set at the end of the piston rod 410 near the gate plate, or it can be set at the end transition section or locally thickened section of the piston rod 410. The mounting part 412 and the gate plate can be fixed or detached by means of threaded connection, pin hinge, flange connection or groove fit. During operation, when the system is started and pressurized oil is introduced into the third oil chamber 320, the oil enters the second oil chamber 510 through the oil passage 411 in the piston rod 410. The oil in the second oil chamber 510 pushes the first piston 400 to move towards the housing cavity 110, and drives the mounting part 412 set on the piston rod 410 to synchronously drive the gate plate to move closer to the drill string in the housing cavity 110. Since the oil passage 411 is located inside the piston rod 410, the hydraulic medium can be quickly transferred between the third oil chamber 320 and the second oil chamber 510 without having to go through a long external pipeline. Therefore, the filling and draining time of the oil can be shortened, the flow resistance and pressure loss can be reduced, and the response speed of the first piston 400 can be improved.

[0111] Simultaneously, the mounting unit 412 reliably positions and transmits force to the gate, ensuring that the gate maintains a coaxial motion relationship with the piston rod 410 under high-pressure well control conditions. This prevents uneven loading, torsion, or loosening of the connection, thereby enabling the gate to obtain a stable pushing path and continuous sealing capability when closing the wellhead. It should be understood that the above embodiments are merely illustrative examples, and any equivalent substitutions or modifications made without departing from the spirit of this application should fall within the protection scope of this application.

[0112] Reference Figure 4 and Figure 6 As shown, based on the aforementioned embodiment, the hydraulic cylinder assembly 300 is further provided with a first oil hole 330 communicating with the third oil chamber 320, the first oil hole 330 being used to supply oil to enter and exit the third oil chamber 320; and / or, the side door 200 is provided with a second oil hole 210 communicating with the first sub-oil chamber 311, the second oil hole 210 being used to supply oil to enter and exit the first sub-oil chamber 311.

[0113] In this application, the first oil port 330 can be an oil supply channel formed on the wall of the hydraulic cylinder assembly 300, used to establish a communication relationship between external hydraulic oil and the third oil chamber 320, so as to realize the input or discharge of oil in the third oil chamber 320. In the gate blowout preventer, the first oil port 330 is responsible for outputting oil to the third oil chamber 320, so that the end of the first piston 400 away from the housing 100 can obtain a stable hydraulic pressure input, and provide a return oil passage when reset or depressurization is required, thereby cooperating with the pressure changes in the second oil chamber 510 and the first oil chamber 310 to realize the opening, closing and holding of the gate. The first oil port 330 can be set in the hydraulic cylinder assembly 300 near the third oil chamber 320, and can be directly connected to hydraulic pipelines, control valve groups or external connectors, so as to realize rapid filling or rapid depressurization according to instructions during well control operations.

[0114] The second oil port 210 on the side door 200 can be a hydraulic communication channel provided on the wall of the side door 200, used to establish a controllable connection between the external oil circuit and the first sub-oil chamber 311, thereby pushing the second piston 500 to move during oil filling, and realizing the gate to quickly open the wellhead by means of the movement of the second piston 500 and the first piston 400. The second oil port 210 can be located in the area corresponding to the first sub-oil chamber 311 of the side door 200, and can be connected to the hydraulic control system through an external oil pipe, valve seat or flange interface, so as to quickly supply oil to the first sub-oil chamber 311 after the well opening command is issued, or to discharge the oil in the first sub-oil chamber 311 when the well is shut in.

[0115] Based on the above analysis, when the system is started, external hydraulic oil can enter the third oil chamber 320 through the first oil hole 330, and then enter the second oil chamber 510 from the third oil chamber 320 through the oil passage 411. This causes the first piston 400 to move towards the housing cavity 110 under the action of the oil pressure in the second oil chamber 510, and drive the gate to complete the initial approach and connection action. At the same time, when it is necessary to open the wellhead, hydraulic oil can also enter the first sub-oil chamber 311 through the second oil hole 210, pushing the second piston 500 and the first piston 400 to move synchronously away from the housing cavity 110, so that the gate moves away from the wellhead center at a stable speed and completes the opening. It should be understood that the above examples are only illustrative and not limiting. Any equivalent substitutions made to the position, hole type, connection method, and sealing form of the first oil hole 330 and the second oil hole 210 without departing from the technical concept of this application shall fall within the protection scope of this application.

[0116] Reference Figure 6 and Figure 7 As shown, in one possible implementation, a through hole 220 is provided on the side door 200, the through hole 220 corresponds to the housing cavity 110, and the first piston 400 passes through the through hole 220 and is mounted on the side door 200, and the through hole 220 is dynamically sealed to the first piston 400.

[0117] The through hole 220 can be understood as a through guide channel provided on the wall of the side door 200. The through hole 220 is structurally aligned with the axial position of the housing cavity 110 so as to provide a passage and motion reference for the first piston 400.

[0118] In one possible embodiment, the through hole 220 allows the end of the first piston 400 with the mounting portion 412 to pass through the side door 200 from the side of the cylinder assembly 300 and enter the housing cavity 110, where it reciprocates along a predetermined axis under hydraulic drive. Simultaneously, the sealing fit within the through hole 220 restricts hydraulic oil leakage between the side door 200 and the first piston 400, thereby maintaining pressure stability in the first oil chamber 310, the second oil chamber 510, and the communicating chambers. The through hole 220 can be located in the mounting area corresponding to the side door 200 and the housing cavity 110, and is coaxially arranged with the first piston 400. The through section of the first piston 400 extends into the housing cavity 110 after passing through the through hole 220 and connects to the gate. The side door 200 and the through hole 220 can be integrally formed, or a mounting hole can be machined on the side door 200 and a guide bushing or sealing sleeve can be inserted to guide and support the first piston 400.

[0119] When the system starts and hydraulic oil is introduced into the corresponding oil chamber, the first piston 400 moves linearly along the axial direction of the through hole 220 of the side door 200 under pressure. The through hole 220 guides and limits the first piston 400, ensuring that the first piston 400 maintains a movement posture corresponding to the housing cavity 110 during its passage through the side door 200, avoiding jamming or sealing failure due to lateral load. Because a dynamic seal is provided between the through hole 220 and the first piston 400, only a controlled, minute amount of lubricating film is allowed during piston reciprocation, without forming a significant leakage channel. Therefore, the hydraulic driving force can be transmitted relatively completely to the end of the gate, allowing the gate to maintain stable force during closing or opening. Simultaneously, the integrated guidance and sealing design of the through hole 220 reduces the sensitivity to assembly errors between the first piston 400 and the side door 200, enabling the first piston 400 to maintain a stable movement trajectory even under high pressure, high vibration, and wellhead disturbance environments, thereby improving the response consistency and sealing reliability of the gate blowout preventer. It should be understood that the above embodiments are merely examples and are not intended to limit this application. Without departing from the overall concept of this application, the relevant hole type, sealing form and material configuration can be adjusted accordingly.

[0120] Reference Figure 1 and Figure 9As shown, based on the aforementioned embodiments, it further includes a plurality of first connectors 600 for connecting the side door 200 and the housing 100; and / or, it also includes a plurality of second connectors 610 for connecting the side door 200 and the hydraulic cylinder assembly 300.

[0121] In this application, the first connector 600 can be a fastening component for fixing the side door 200 to the housing 100. The function of the first connector 600 is to stably lock the side door 200 to the corresponding mounting end face of the housing 100 when the blowout preventer is subjected to wellhead pressure, shut-in reaction force, and hydraulic drive load, thereby limiting the tendency of the side door 200 to separate from the housing 100 and ensuring the integrity of the housing cavity 110 and the corresponding sealing surface. The first connector 600 is distributed along the circumference or edge of the side door 200 and mates with the corresponding connection holes on the housing 100 and the side door 200. During installation, it passes through the flange of the side door 200 and the flange of the housing 100 and applies a preload to form a uniform and reliable clamping state between the side door 200 and the housing 100.

[0122] In one possible embodiment, the first connector 600 can be implemented using high-strength bolts, studs, tie rods, or screws, or alternatively, using clamps, quick-release latches, or pin locking structures. Bolts or studs are suitable for bearing large axial preload loads, tie rods are suitable for bridging thicker flange structures, and clamps or quick-release latches are suitable for applications requiring rapid disassembly and maintenance.

[0123] The first connecting member 600 can be made of high-strength alloy steel, heat-treated carbon steel, steel with anti-corrosion coating, or corrosion-resistant alloy steel to meet the long-term service requirements of humid, sulfur-containing, or salt-containing environments at the well site. The second connecting member 610 can be a fastening component used to connect and fix the side door 200 to the hydraulic cylinder assembly 300. The main function of the second connecting member 610 is to stably install the hydraulic cylinder assembly 300 on the side door 200, forming the first oil cavity 310 together with the side door 200, while ensuring that the hydraulic cylinder assembly 300 does not loosen, shift, or leak locally when subjected to hydraulic drive reaction force and well shut-in impact load. The second connecting member 610 can be arranged at the connecting flange of the hydraulic cylinder assembly 300 and the side door 200, and evenly distributed circumferentially, so as to press the hydraulic cylinder assembly 300 and the side door 200 tightly together under pressure, forming a continuous oil cavity boundary and reliable structural support.

[0124] In one possible embodiment, the second connector 610 can be implemented using bolts, studs, a combination of pressure plates and locating pins, an annular clamp, or welded reinforcements. Bolts or studs facilitate disassembly and maintenance, the combination of pressure plates and locating pins helps improve assembly and positioning accuracy, the annular clamp is suitable for peripheral clamping installation, and welded reinforcements are suitable for scenarios with higher requirements for connection rigidity and less need for subsequent disassembly.

[0125] The second connector 610 may be made of high-strength steel, corrosion-resistant alloy steel, or quenched and tempered structural steel to improve its tensile, shear and fatigue resistance.

[0126] When the system starts, the hydraulic cylinder assembly 300, side door 200, and housing 100 are pre-tightened and positioned under the constraints of the first connector 600 and the second connector 610. The connection interface forms a stable structural boundary under the pressure of the flange face, ensuring that the housing cavity 110, the first oil cavity 310, and related oil circuits remain geometrically stable under high pressure. Subsequently, during well shut-in or well opening, hydraulic medium enters the corresponding oil cavity and drives the first piston 400 and the second piston 500 to move in coordination. The connectors continuously bear the separation load and shear load caused by oil pressure, gate reaction force, and wellhead operating condition fluctuations, ensuring that the side door 200 is always reliably attached to the housing 100 and that the hydraulic cylinder assembly 300 is held in the predetermined installation position.

[0127] Because the first connector 600 ensures the overall locking between the side door 200 and the housing 100, and the second connector 610 further ensures the boundary stability between the hydraulic cylinder assembly 300 and the side door 200, the structural connection will not loosen significantly during the entire process of rapid entry and exit of the hydraulic medium into and out of the oil chamber, piston reciprocating motion, and gate contact and sealing with the drill string. Changes in oil chamber volume and displacement of the sealing surface can also be effectively controlled. It should be understood that the above examples are merely illustrative and not limiting. Any equivalent substitutions in form, quantity, arrangement, and material of the first connector 600 and the second connector 610 without departing from the overall concept of this application should fall within the protection scope of this application.

[0128] This application provides a method for using a dual-mode cooperative hydraulically driven gate blowout preventer. The dual-mode cooperative hydraulically driven gate blowout preventer has the structure described above, and the method of use includes:

[0129] The housing 100 of the gate blowout preventer is connected to the wellhead of the well, so that the housing cavity 110 of the housing 100 corresponds to the wellhead.

[0130] When the well pressure during drilling is less than a preset value, oil is injected into the second oil chamber 510 of the hydraulic cylinder assembly 300 in the gate blowout preventer. The oil in the second oil chamber 510 pushes the first piston 400 of the gate blowout preventer toward the housing 100, so that the gate connected to the first piston 400 is connected to the drill string in the housing cavity 110.

[0131] Oil is continuously injected into the second oil chamber 510. The oil enters the second sub-oil chamber 312. The oil in the second sub-oil chamber 312 of the gate blowout preventer pushes the second piston 500 of the gate blowout preventer, which in turn drives the first piston 400 to move toward the housing chamber 110, thereby driving the gate to close the wellhead.

[0132] When the well pressure in the well is greater than or equal to a preset value, oil is injected into the second oil chamber 510. The oil flows directly to the second sub-oil chamber 312. The oil in the second sub-oil chamber 312 pushes the second piston 500 and the first piston 400 to move simultaneously, thereby driving the gate to close the wellhead.

[0133] When using the above method, the housing 100 is first connected to the wellhead, and the housing cavity 110 inside the housing 100 is connected to the wellhead, so that when the first piston 400 drives the gate to move toward the housing cavity 110, the gate can close the wellhead.

[0134] A device for detecting well pressure is installed at the wellhead. The pressure value of the detection device is preset. When the well pressure is less than the preset value, oil is injected into the third oil chamber 320 through the first oil hole 330 on the hydraulic cylinder assembly 300. The oil in the third oil chamber 320 flows into the second oil chamber 510 through the oil passage 411 in the piston rod 410. The oil in the second oil chamber 510 pushes the first piston 400 to move toward the housing cavity 110, so that the gate plate is preferentially connected to the drill string or another gate plate. This enables rapid pre-contact with a smaller driving volume, thereby shortening the initial response time and achieving rapid well shut-in.

[0135] After the gate is connected to the drill string, the drill string or another gate will give the first piston 400 a reverse thrust. At this time, the first piston 400 is difficult to push with the oil in the second oil chamber 510. After continuous oil injection, the oil enters the second sub-oil chamber 312 from the second oil chamber 510 through the overflow valve 520, and then the second piston 500 drives the first piston 400 to continue to advance, so that the gate obtains a greater sealing driving force after completing the contact. At this time, the first piston 400 is simultaneously pushed by the second oil chamber 510 and the second piston 500, thus taking into account both rapid well shut-in and reliable sealing.

[0136] When the detection device at the wellhead detects that the well pressure is greater than or equal to the preset value, the well pressure will hinder the advancement of the first piston 400 during the initial advance. The oil directly pushes open the overflow valve 520 and flows from the second oil chamber 510 to the second sub-oil chamber 312, pushing the second piston 500 and the first piston 400 to move synchronously. The first piston 400 is thrust by the second oil chamber 510 and the second piston 500 from the very beginning, thereby establishing the shut-in thrust adapted to high well pressure more quickly, avoiding the sluggish action of a single piston under high reaction force, and thus improving shut-in efficiency, sealing reliability and well control safety.

[0137] During the well shut-in operation described above, the first piston 400 and the second piston 500 move toward the housing cavity 110, and the oil in the first sub-oil cavity 311 flows out of the hydraulic cylinder assembly 300 through the second oil hole 210 on the side door 200, thereby completing the circulation of the oil.

[0138] Based on the foregoing embodiments, the method of using the dual-mode coordinated hydraulically driven gate blowout preventer further includes:

[0139] Oil is injected into the first sub-oil chamber 311 of the gate blowout preventer. The oil pushes the first piston 400 and the second piston 500 to move simultaneously in a direction away from the housing cavity 110, so that the gate is disengaged from the drill string in the housing cavity 110.

[0140] When well opening operations are required, oil is injected into the first sub-oil chamber 311 of the gate blowout preventer through the second oil port 210 on the side door 200. The oil in the first sub-oil chamber 311 pushes the first piston 400 and the second piston 500 to move simultaneously away from the housing cavity 110, so that the gate is disengaged from the drill string in the housing cavity 110. As the first piston 400 and the second piston 500 move away from the housing cavity 110, the oil in the second sub-oil chamber 312 flows into the second oil chamber 510 through the one-way valve 530. The oil in the second oil chamber 510 flows into the third oil chamber 320 through the oil passage 411 in the piston rod 410, and finally flows out of the hydraulic cylinder assembly 300 through the first oil port 330, thus completing the oil circulation.

Claims

1. A dual-mode cooperative hydraulically driven gate blowout preventer, characterized in that, include: A housing (100) is provided with a housing cavity (110) inside the housing (100), the housing cavity (110) is used to connect with the wellhead, and a gate is provided inside the housing cavity (110); A side door (200) is connected to the housing (100) and is used to close the housing cavity (110). A hydraulic cylinder assembly (300) is connected to the side door (200), and the hydraulic cylinder assembly (300) and the side door (200) form a first oil chamber (310). The first piston (400) is inserted into the hydraulic cylinder assembly (300) and the side door (200). The hydraulic cylinder assembly (300) and the side door (200) are both dynamically sealed to the first piston (400). The first piston (400) is connected to the gate. The second piston (500) is sleeved on the first piston (400). The second piston (500) is provided with a second oil chamber (510). The first piston (400) is connected to the second oil chamber (510). The second piston (500) is disposed in the first oil chamber (310). The second piston (500) divides the first oil chamber (310) into a first sub-oil chamber (311) and a second sub-oil chamber (312). The outer wall of the second piston (500) is dynamically sealed to the inner wall of the first oil chamber (310). The first piston (400) is configured to move toward the housing cavity (110) under the influence of oil entering the second oil chamber (510) so that the gate closes the wellhead; The second piston (500) is configured to move simultaneously with the first piston (400) under the influence of the oil entering the second sub-oil chamber (312) to drive the gate to close the wellhead.

2. The dual-mode cooperative hydraulically driven gate blowout preventer according to claim 1, characterized in that, The second piston (500) is provided with an overflow valve (520), which is configured to open when the oil pressure in the second oil chamber (510) is greater than or equal to a preset value, so as to connect the second oil chamber (510) and the second sub-oil chamber (312), so that the second piston (500) moves and pushes the first piston (400) toward the housing cavity (110); And / or, the second piston (500) is also provided with a one-way valve (530), when the oil in the first sub-oil chamber (311) pushes the first piston (400) and the second piston (500) to move away from the housing cavity (110), the oil in the second sub-oil chamber (312) enters the second oil chamber (510) through the one-way valve (530).

3. The dual-mode coordinated hydraulically driven gate blowout preventer according to claim 1, characterized in that, The hydraulic cylinder assembly (300) is provided with a third oil chamber (320), and the end of the first piston (400) away from the housing (100) is sealed to the hydraulic cylinder assembly (300), and part of the first piston (400) is located in the third oil chamber (320); The third oil chamber (320) is configured to communicate with the second oil chamber (510) when oil is introduced into the third oil chamber (320) so that oil enters the second oil chamber (510). The third oil chamber (320) is also configured to communicate with the second oil chamber (510) when oil is introduced into the first sub-oil chamber (311) to push the second piston (500) to move, so that oil enters the third oil chamber (320).

4. The dual-mode cooperative hydraulically driven gate blowout preventer according to claim 3, characterized in that, The first piston (400) includes a piston rod (410) and a piston body (420) disposed on the piston rod (410). One end of the piston rod (410) is connected to the gate, and the other end of the piston rod (410) is sealed to the hydraulic cylinder assembly (300). The piston body (420) is dynamically sealed to the inner wall of the second piston (500). The end of the piston body (420) away from the housing (100) and the inner wall of the second piston (500) form the second oil chamber (510).

5. The dual-mode cooperative hydraulically driven gate blowout preventer according to claim 4, characterized in that, An oil passage (411) is provided inside the piston rod (410), and the oil passage (411) connects the third oil chamber (320) and the second oil chamber (510). And / or, a mounting portion (412) is provided on the piston rod (410), the mounting portion (412) being used to mount the gate.

6. The dual-mode cooperative hydraulically driven gate blowout preventer according to claim 5, characterized in that, The hydraulic cylinder assembly (300) is also provided with a first oil hole (330) communicating with the third oil chamber (320), and the first oil hole (330) is used to supply oil to enter and exit the third oil chamber (320). And / or, the side door (200) is provided with a second oil hole (210) communicating with the first sub-oil chamber (311), the second oil hole (210) being used to supply oil to enter and exit the first sub-oil chamber (311).

7. The dual-mode cooperative hydraulically driven gate blowout preventer according to any one of claims 1-6, characterized in that, The side door (200) is provided with a through hole (220), which corresponds to the housing cavity (110). The first piston (400) passes through the through hole (220) on the side door (200), and the through hole (220) is dynamically sealed to the first piston (400).

8. The dual-mode cooperative hydraulically driven gate blowout preventer according to claim 7, characterized in that, It also includes a plurality of first connectors (600) for connecting the side door (200) and the housing (100). And / or, also includes a plurality of second connectors (610) for connecting the side door (200) and the cylinder assembly (300).

9. A method of using the dual-mode cooperative hydraulically driven gate blowout preventer according to any one of claims 1-8, characterized in that, include: The housing (100) of the gate blowout preventer is connected to the wellhead of the well, such that the housing cavity (110) of the housing (100) corresponds to the wellhead; When the well pressure in the well is less than a preset value, oil is injected into the second oil chamber (510) of the hydraulic cylinder assembly (300) in the gate blowout preventer. The oil pushes the first piston (400) of the gate blowout preventer toward the housing (100) in the second oil chamber (510) so that the gate connected to the first piston (400) is connected to the drill string in the housing cavity (110) or to another gate. Oil is continuously injected into the second oil chamber (510), and the oil enters the second sub-oil chamber (312). The oil in the second sub-oil chamber (312) of the gate blowout preventer pushes the second piston (500) of the gate blowout preventer to drive the first piston (400) to move toward the housing cavity (110) so as to drive the gate to close the wellhead. When the well pressure in the well is greater than or equal to the preset value, oil is injected into the second oil chamber (510), and the oil flows directly to the second sub-oil chamber (312). The oil in the second sub-oil chamber (312) pushes the second piston (500) and the first piston (400) to move simultaneously, thereby driving the gate to close the wellhead.

10. The method of using the dual-mode cooperative hydraulically driven gate blowout preventer according to claim 9, characterized in that, Also includes: Oil is injected into the first sub-oil chamber (311) of the gate blowout preventer. The oil pushes the first piston (400) and the second piston (500) in the first sub-oil chamber (311) to move in a direction away from the housing cavity (110) at the same time, so that the gate is disengaged from the drill string or another gate in the housing cavity (110).

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