Annular blowout preventer and well control system

Abstract

The invention provides an annular blowout preventer and a well control system, and belongs to the field of petroleum drilling engineering. A containing cavity is formed in a shell part of the annular blowout preventer, and through holes communicating with the containing cavity are formed in the two opposite sides of the shell part. The piston piece is located in the containing cavity and used for ascending and descending between the two through holes. The at least three hard alloy blocks are all in sliding connection with the piston piece, each hard alloy block is provided with a first sealing part facing the adjacent hard alloy block and a second sealing part deviating from the piston piece, and the hard alloy blocks are mutually gathered under the driving of lifting of the piston piece, so that the adjacent first sealing parts abut against each other; the second sealing parts abut against each other or are used for jointly embracing a drill rod in a well control system penetrating through the through holes so as to block the two through holes. And the first sealing part and the second sealing part slide along with the corresponding hard alloy blocks so as to communicate the two through holes. In this way, the hard alloy blocks are good in compression resistance and not prone to aging, and the service life of the whole sealing assembly can be prolonged.

Description

Technical Field

[0001] The present application relates to the field of oil drilling engineering, and in particular to an annular blowout preventer and a well control system. Background Art

[0002] The annular blowout preventer is the core equipment in the well control system, which is used to seal the annular space at the wellhead to provide safety protection to prevent blowouts.

[0003] In related technologies, an annular blowout preventer is mainly composed of a shell, a top cover, a piston and a rubber core. When the wellhead needs to be closed, the piston is pushed upward by a hydraulic device to compress the rubber core, causing it to deform and tightly wrap around the drill pipe or other downhole tools to prevent high-pressure fluid from spraying out of the well.

[0004] However, the rubber core in the above-mentioned annular blowout preventer has poor pressure resistance and is prone to aging, resulting in a short service life. Summary of the Invention

[0005] The present application provides an annular blowout preventer and a well control system to solve the problems in the related art of the rubber core in the annular blowout preventer having poor pressure resistance, easy aging and short service life.

[0006] In one aspect, the present application provides an annular blowout preventer, comprising:

[0007] A shell member, wherein the shell member has an accommodating cavity therein, and through holes communicating with the accommodating cavity are formed on opposite sides of the shell member;

[0008] A piston member is located in the accommodating cavity and is used to move up and down between the two through holes;

[0009] A sealing assembly includes at least three carbide blocks, each of which is slidably connected to a piston member. The carbide blocks are provided with a first sealing portion and a second sealing portion, wherein the first sealing portion is arranged toward an adjacent carbide block and the second sealing portion is arranged away from the piston member. The carbide blocks are configured to converge toward or move away from each other under the drive of the piston member to rise and fall. When converging toward each other, the adjacent first sealing portions abut against each other, and the second sealing portions abut against each other or are used to jointly embrace a drill pipe in a well control system passing through a through hole to block the two through holes. When moving away from each other, the first sealing portion and the second sealing portion slide following the corresponding carbide block to connect the two through holes.

[0010] In a possible implementation, the annular blowout preventer provided by the present application has at least four cemented carbide blocks;

[0011] Adjacent first sealing portions abut against each other to form at least four first sealing lines, and the first sealing lines extend obliquely along the extension direction of the corresponding cemented carbide block; the second sealing portions abut against each other to form a second sealing line extending along the diameter direction of the through hole, or the second sealing portions together form spiral teeth, and the spiral teeth extend spirally along the axial direction of the through hole. The spiral teeth are used to match and plug with the spiral tooth grooves on the circumferential side of the drill rod, so that the second sealing portions together embrace the drill rod; to block the two through holes.

[0012] In a possible implementation, the annular blowout preventer provided in the present application further includes a first sleeve, the piston member is slidably sleeved on the first sleeve, and the first sleeve is coaxially arranged with the through hole;

[0013] The piston member has a first inclined surface on the side facing the first sleeve, and the carbide block has a second inclined surface on the side facing the piston member; the carbide block has a first side and a second side opposite to each other, the first side is in contact with the first sleeve, and the second side is in contact with the inner wall of the shell member; the second inclined surface is configured to slide along the first inclined surface under the drive of the piston member to move the corresponding carbide block toward or away from the axis of the through hole, so that the carbide blocks gather together or move away from each other.

[0014] In one possible implementation, the annular blowout preventer provided in this application, the first sleeve includes:

[0015] a sleeve portion, on which the piston member is slidably sleeved;

[0016] The limiting portion is connected to the sleeve portion and is arranged around the circumference of the sleeve portion. The limiting portion is configured to abut against the piston member when the cemented carbide blocks gather together.

[0017] In one possible implementation, the annular blowout preventer provided in the present application further includes at least three sliding members, which are connected to the carbide blocks in a one-to-one correspondence; at least three sliding grooves are spaced apart on the circumferential side of the piston member, and the sliding grooves are located on the first inclined surface; the sliding members are placed in the sliding grooves in a one-to-one correspondence, and the sliding members are configured to move along the extension direction of the sliding grooves when the piston member is raised or lowered.

[0018] In a possible implementation, the annular blowout preventer provided in the present application comprises a sliding member, the sliding member being connected to a corresponding carbide block, and the sliding member being placed in a sliding groove; or

[0019] The sliding part includes a second slider and a pin located in the slide groove. The second slider is connected to the corresponding carbide block. A socket is provided on the second slider. The pin rod of the pin shaft is transitionally plugged into the socket so that the pin shaft cap of the pin shaft contacts one side of the second slider; a groove is provided on the peripheral side of the pin rod adjacent to the other side of the second slider, a retaining ring is provided on the groove, and a gasket is sleeved on the retaining ring, and the gasket contacts the other side of the second slider.

[0020] In a possible implementation, the annular blowout preventer provided by the application further comprises a second sleeve, the second sleeve is located in the accommodating cavity, and the first sleeve is located in the second sleeve, and the second sleeve is coaxially arranged with the first sleeve; the piston member is in sliding connection with the second sleeve.

[0021] In a possible implementation, the annular blowout preventer provided by the application, the shell member comprises a shell part and a cover part arranged on the shell part; the shell part and the cover part jointly enclose the accommodating cavity, and the shell part and the cover part are both provided with a through hole; the cover part has an abutting part on the side facing the shell part, the abutting part is in communication with the through hole, and the side of the abutting part away from the cover part is used to be attached to the second side; the circumferential side of the abutting part has a third inclined surface matched with the first inclined surface, and the third inclined surface is used to abut against part of the first inclined surface when the hard alloy blocks are gathered together.

[0022] In a possible implementation, the annular blowout preventer provided by the application, the first side and the second side are both coated with a wear-resistant coating.

[0023] On the other hand, the application provides a well control system, comprising a system body and any one of the annular blowout preventers described above arranged on the system body; the system body comprises a drill pipe and a hydraulic device; the annular blowout preventer is arranged in a well, and the drill pipe passes through the two through holes of the shell member of the annular blowout preventer in sequence to be partially located in the well; the hydraulic device is used to inject hydraulic oil into the accommodating cavity of the shell member to lift or lower the piston member, and the hard alloy blocks of the annular blowout preventer are used to gather together or move away from each other under the driving of the lifting or lowering of the piston member to close or open the wellhead of the well.

[0024] The annular blowout preventer and the well control system provided by the application, the annular blowout preventer is provided with a shell member, the shell member has an accommodating cavity, and the opposite sides of the shell member are both provided with a through hole in communication with the accommodating cavity; the piston member is located in the accommodating cavity and is used to lift or lower between the two through holes; at least three hard alloy blocks are provided, each of the hard alloy blocks is in sliding connection with the piston member, the hard alloy block has a first sealing part and a second sealing part, the first sealing part is arranged towards the adjacent hard alloy block, and the second sealing part is arranged away from the piston member; each of the hard alloy blocks is used to gather together or move away from each other under the driving of the lifting or lowering of the piston member; when gathering together, each of the adjacent first sealing parts abuts against each other, and each of the second sealing parts abuts against each other or is used to jointly hold the drill pipe in the well control system passing through the through hole to block the two through holes; when moving away from each other, the first sealing part and the second sealing part slide with the corresponding hard alloy block to communicate the two through holes.

[0025] Thus, by providing at least three cemented carbide blocks, the first and second sealing portions ensure full contact between the blocks, evenly distributing forces and forming a stable sealing structure. Furthermore, a more complex and / or longer sealing path can be constructed to block the two through-holes, achieving a better sealing effect. The high-density structure of the cemented carbide blocks provides high hardness and strength, and excellent compressive resistance. Furthermore, the cemented carbide blocks are chemically inert and highly resistant to ultraviolet light, oxygen, and other environmental factors, preventing aging issues caused by chemical corrosion and thus extending the service life of the entire sealing assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0027] Figure 1 A schematic diagram of the structure of the annular blowout preventer provided for this application;

[0028] Figure 2 for Figure 1 A schematic diagram of the structure of the sealing component;

[0029] Figure 3 Use of the annular blowout preventer provided for this application Figure 1 ;

[0030] Figure 4 Use of the annular blowout preventer provided for this application Figure 2 ;

[0031] Figure 5 for Figure 3 Schematic diagram of some structures in ;

[0032] Figure 6 for Figure 4 Schematic diagram of some structures in ;

[0033] Figure 7 for Figure 1 A schematic structural diagram of the first sleeve in FIG.

[0034] Figure 8 for Figure 6 Schematic diagram of the structure of the pin shaft;

[0035] Figure 9 for Figure 8 The connection diagram of the pin rod and the pin cap;

[0036] Figure 10 for Figure 1 A schematic structural diagram of the piston member;

[0037] Figure 11 for Figure 10Schematic diagram of the internal structure at A in the middle;

[0038] Figure 12 for Figure 1 Schematic diagram of the structure of the cover part.

[0039] Description of reference numerals:

[0040] 100 - housing member; 110 - accommodating chamber; 111 - first sub-accommodating chamber; 112 - second sub-accommodating chamber; 120 - through hole; 101 - housing portion; 102 - cover portion; 1021 - abutting portion; 1022 - third inclined surface;

[0041] 200 - piston member; 210 - mating portion; 211 - first inclined surface; 212 - sliding groove; 220 - sliding portion; 221 - sliding section; 2211 - sliding cavity; 2212 - opening; 222 - contact section;

[0042] 300 - sealing assembly; 310 - carbide block; 311 - second inclined surface; 312 - first side; 313 - second side; 3141 - first sealing portion; 3142 - second sealing portion; 301 - first sealing line; 302 - second sealing line;

[0043] 400-first sleeve; 410-sleeve portion; 420-limiting portion;

[0044] 500-second sleeve;

[0045] 600-sliding part; 610-second sliding block; 620-pin; 6211-pin cap; 6212-pin rod; 6213-groove; 6221-circlip; 6222-gasket. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described in more detail below in conjunction with the drawings in the preferred embodiments of the present application. In the drawings, the same or similar reference numerals throughout represent the same or similar parts or parts with the same or similar functions. The described embodiments are part of the embodiments of the present application, not all of the embodiments. The embodiments described below with reference to the drawings are exemplary and are intended to be used to explain the present application, and should not be understood as limitations on the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. The embodiments of the present application are described in detail below in conjunction with the drawings.

[0047] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to a fixed connection, an indirect connection via an intermediate medium, internal communication between two components, or an interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0048] In the description of this application, it should be understood that the terms "up", "down", "front", "back", "left", "right", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limitations on this application.

[0049] The terms "first," "second," "third," "fourth," and the like in the specification and claims of this application and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a particular order or sequential sequence. It should be understood that the terms used in this manner are interchangeable where appropriate, such that the embodiments of the application described herein can, for example, be implemented in an order other than that illustrated or described herein.

[0050] In addition, the terms "comprises" and "having" and any variations thereof are intended to cover a non-exclusive inclusion. For example, a process, method, system, product or apparatus that includes a series of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, product or apparatus.

[0051] As mentioned in the background technology, the annular blowout preventer in the related art is mainly composed of a shell, a top cover, a piston and a rubber core. When the wellhead needs to be closed, the piston is pushed upward by a hydraulic device to compress the rubber core, causing the rubber core to deform and tightly wrap around the drill pipe or other downhole tools to prevent high-pressure fluid from spraying out of the well.

[0052] However, the rubber core in the above-mentioned annular blowout preventer is made of rubber. As a highly elastic polymer material, rubber has good elasticity and flexibility, but it is prone to permanent deformation or rupture when subjected to continuous high pressure, which limits the pressure resistance of the rubber core. At the same time, the physical properties of rubber materials are relatively sensitive to temperature changes. Under high temperature conditions, the hardness, elasticity and compressive strength of rubber will all change, resulting in a decrease in the rubber core's resistance to high-pressure erosion.

[0053] In addition, when rubber is exposed to an oxygen environment, an oxidation reaction will occur, causing the rubber molecular chain to break, thereby reducing the elasticity and strength of the rubber and causing aging; at the same time, acids, alkalis, oils and other chemicals in the drilling process will corrode the rubber, further promoting its aging.

[0054] Therefore, the rubber core in the above-mentioned annular blowout preventer has poor pressure resistance and is prone to aging, resulting in a short service life.

[0055] In view of this, an embodiment of the present application provides an annular blowout preventer and a well control system, wherein the annular blowout preventer is provided with a shell member, wherein the shell member has an accommodating cavity, and through holes connected to the accommodating cavity are opened on opposite sides of the shell member; a piston member is located in the accommodating cavity, and the piston member is used to rise and fall between the two through holes; at least three carbide blocks are provided, and each carbide block is slidably connected to the piston member, and the carbide block has a first sealing portion and a second sealing portion, the first sealing portion is arranged toward the adjacent carbide block, and the second sealing portion is arranged away from the piston member; each carbide block is used to gather together or move away from each other under the drive of the lifting and lowering of the piston member; wherein, when gathering together, each adjacent first sealing portion abuts against each other, and each second sealing portion abuts against each other or is used to jointly embrace the drill pipe in the well control system passing through the through hole to block the two through holes; when moving away from each other, the first sealing portion and the second sealing portion slide following the corresponding carbide block to connect the two through holes.

[0056] Thus, by providing at least three cemented carbide blocks, the first and second sealing portions ensure full contact between the blocks, evenly distributing forces and forming a stable sealing structure. Furthermore, a more complex and / or longer sealing path can be constructed to block the two through-holes, achieving a better sealing effect. The high-density structure of the cemented carbide blocks provides high hardness and strength, and excellent compressive resistance. Furthermore, the cemented carbide blocks are chemically inert and highly resistant to ultraviolet light, oxygen, and other environmental factors, preventing aging issues caused by chemical corrosion and thus extending the service life of the entire sealing assembly.

[0057] Hereinafter, the present application will be described in detail with reference to the accompanying drawings and specific embodiments.

[0058] See Figures 1 to 4 The annular blowout preventer provided in an embodiment of the present application includes a shell member 100, a piston member 200 and a sealing assembly 300. The shell member 100 has an accommodating chamber 110, and two opposite sides of the shell member 100 are provided with through holes 120 connected to the accommodating chamber 110; the piston member 200 is located in the accommodating chamber 110 and is used to rise and fall between the two through holes 120; the sealing assembly 300 includes at least three carbide blocks 310, each of which is slidably connected to the piston member 200.

[0059] The cemented carbide block 310 has a first sealing portion 3141 and a second sealing portion 3142, wherein the first sealing portion 3141 is arranged toward the adjacent cemented carbide block 310, and the second sealing portion 3142 is arranged away from the piston member 200; each cemented carbide block 310 is configured to gather together or move away from each other under the drive of the piston member 200 to rise and fall; wherein, when gathering together, each adjacent first sealing portion 3141 abuts against each other, and each second sealing portion 3142 abuts against each other or is used to jointly embrace the drill pipe in the well control system passing through the through hole 120 to block the two through holes 120; when moving away from each other, the first sealing portion 3141 and the second sealing portion 3142 slide following the corresponding cemented carbide block 310 to connect the two through holes 120.

[0060] Among them, the annular blowout preventer of the embodiment of the present application is used to be set in the well to be drilled. The annular blowout preventer can seal the wellhead of an empty well to be drilled, or it can seal the wellhead of a well to be drilled with a drill pipe or other downhole tools installed. The embodiment of the present application is not limited to this.

[0061] Specifically, the shell 100 serves as the basic bearing structure of the entire annular blowout preventer, is used to accommodate the piston 200 and the sealing assembly 300, and provides an external connection interface.

[0062] Here, the external connection interface can be configured based on actual usage requirements. For example, the external connection interface includes a flange interface. When the annular blowout preventer is installed in the well to be drilled, the housing 100 is tightly connected to the wellhead equipment (such as the casing head, cross-joint, etc.) through the flange. The external connection interface can also include a pressure gauge interface or a pressure relief valve interface. In this way, a pressure sensor or manual / automatic pressure relief device can be installed to monitor the pressure changes in the well in real time and quickly release excessive pressure when necessary to protect equipment and personnel. Alternatively, the piston 200 can be raised and lowered using power provided by a hydraulic device. An interface for connecting a hydraulic pipeline is provided on the housing 100 to guide hydraulic oil into the accommodating chamber 110 to push the piston 200 up and down. In this way, the operator can close or open the annular blowout preventer through remote control, improving the safety and efficiency of the operation.

[0063] The piston 200 is used as a driving element to realize the gathering and separation of the carbide blocks 310 in the sealing assembly 300. In actual application, the piston 200 rises to Figure 3 The position shown changes to Figure 4 The position shown in FIG. 2 makes each carbide block 310 gather together, that is, the piston member 200 moves toward the wellhead in the well, and the moving direction is the opposite direction of gravity; the piston member 200 descends to Figure 4 The position shown changes to Figure 3In the position shown, the carbide blocks 310 are separated, that is, the piston member 200 moves away from the wellhead, and the moving direction is the direction of gravity.

[0064] By setting the number of cemented carbide blocks 310 to at least three, for example, the number of cemented carbide blocks 310 can be three, four, five, six, or eight. Adjacent first sealing portions 3141 abut against each other, and second sealing portions 3142 abut against each other or are used to collectively embrace a drill pipe (not shown) in a well control system passing through through-hole 120, the cemented carbide blocks 310 are in full contact with each other, thereby balancing the force and forming a stable sealing structure. Simultaneously, a more complex and / or longer sealing path is constructed. Thus, building on the advantage of high-pressure erosion resistance of the cemented carbide blocks 310, structural optimization enables the cemented carbide blocks 310 to form a multi-level buffer under high pressure in the well. When mud erodes the sealing assembly 300, the mud needs to pass through more complex gaps to leak, thereby reducing the risk of mud leakage. As a result, the sealing assembly 300 can achieve a stable and effective sealing effect on the wellhead.

[0065] For example, when an annular blowout preventer is used in an empty well, each carbide block 310 can be configured as an identical triangular wedge-shaped structure. The inclined planes on opposite sides of the carbide block 310 can serve as the first sealing portion 3141, and the straight side of the carbide block 310 can serve as the second sealing portion 3142. In this way, when the carbide blocks 310 are brought together, the sealing assembly 300 as a whole assumes a cylindrical block-like structure. The carbide blocks 310 can fully contact each other to balance the forces, forming a stable sealing structure. Simultaneously, the abutment of adjacent first sealing portions 3141 and second sealing portions 3142 creates sealing lines located on at least three different radii within the sealing assembly 300, thereby constructing a relatively complex sealing path.

[0066] It will be appreciated that when the annular blowout preventer is used in a well with a drill pipe having a cylindrical body, each second sealing portion 3142 can be configured as a curved surface with a uniform curvature. When the carbide blocks 310 are brought together, the curved surfaces form a circular groove that matches the cylindrical body. The circular groove connects the two through-holes 120 in the housing 100, and the groove walls of the circular groove closely align with the circumferential sidewalls of the cylindrical body. In this way, the curved surfaces closely align with the circumferential sidewalls of the drill pipe, allowing the second sealing portions 3142 to collectively embrace the drill pipe, thereby blocking the two through-holes 120.

[0067] Alternatively, based on the above, the hardness of the cemented carbide blocks 310 may be higher than that of the drill rod, and the curved surfaces may be provided with raised, fine threads. In this way, when the cemented carbide blocks 310 are brought together, forming a circular groove that matches the cylindrical rod, the fine threads can be actively embedded in the drill rod, ensuring a tighter fit between the groove walls and the cylindrical rod's circumference.

[0068] In actual application, the first sealing portion 3141 and the second sealing portion 3142 can be precisely processed to ensure that the first sealing portions 3141 have a high degree of fit when abutting against each other and that the second sealing portions 3142 can fully embrace the drill pipe, thereby improving the sealing effect.

[0069] The cemented carbide block 310 of the embodiment of the present application may include at least one of tungsten carbide-based cemented carbide, titanium carbide-based cemented carbide, titanium nitride-based cemented carbide, and titanium aluminum carbonitride-based cemented carbide.

[0070] Among them, tungsten carbide-based cemented carbide has excellent hardness and compressive strength; titanium carbide-based cemented carbide has high heat resistance, oxidation resistance, and a low coefficient of friction; titanium nitride-based cemented carbide has high hardness, excellent corrosion resistance, and a low coefficient of friction. Titanium aluminum carbonitride-based cemented carbide combines the advantages of titanium carbide, titanium nitride, and aluminum, providing extremely high hardness, wear resistance, and good high-temperature stability.

[0071] Furthermore, the performance of the cemented carbide block 310 can be optimized by combining tungsten carbide-based cemented carbide and titanium carbide-based cemented carbide. For example, the composite method can be to create a double-layer or multi-layer structure, in which the outer layer uses titanium carbide-based cemented carbide to take advantage of its low friction coefficient and excellent oxidation resistance, thereby reducing wear and improving corrosion resistance; while the inner layer uses tungsten carbide-based cemented carbide, which provides a solid support foundation with its high hardness and high strength, ensuring the stability and compressive resistance of the overall structure of the cemented carbide block 310.

[0072] Furthermore, functionally gradient material technology can be applied to achieve a smooth transition from a tungsten carbide-rich core region to a titanium carbide-rich surface layer within the cemented carbide block 310. This ensures the robustness of the internal structure while optimizing surface properties to accommodate complex operating conditions. Alternatively, a particle-reinforced composite material can be constructed by adding titanium carbide particles to a tungsten carbide-based matrix. By adjusting the proportion of titanium carbide particles, the properties of the cemented carbide block 310 can be customized, for example, increasing hardness while maintaining a certain level of toughness, resulting in a cemented carbide block 310 with excellent wear resistance, oxidation resistance, and high strength.

[0073] In summary, the annular blowout preventer of the present embodiment, by providing at least three carbide blocks 310, utilizes a first sealing portion 3141 and a second sealing portion 3142 to ensure full contact between the carbide blocks 310 for balanced force, forming a stable sealing structure. Furthermore, a relatively complex and / or long sealing path is constructed to block the two through-holes 120, achieving a good sealing effect. The high-density structure of the carbide blocks 310 provides high hardness and strength, and excellent compressive resistance. Furthermore, the carbide blocks 310 are chemically inert and highly resistant to ultraviolet rays, oxygen, and other environmental factors. This prevents aging problems caused by chemical corrosion, and helps extend the service life of the entire sealing assembly 300.

[0074] See Figures 2 to 6 In some embodiments, the number of cemented carbide blocks 310 is at least four; adjacent first sealing portions 3141 abut against each other to form at least four first sealing lines 301, and the first sealing lines 301 extend obliquely along the extension direction of the corresponding cemented carbide block 310; the second sealing portions 3142 abut against each other to form a second sealing line 302 extending along the diameter direction of the through hole 120 to block the two through holes 120.

[0075] In this way, when the annular blowout preventer seals the wellhead of an empty well, the contact area between each cemented carbide block 310 is increased by forming the second sealing line 302 and at least four first sealing lines 301, thereby forming a more stable sealing structure; and the sealing assembly 300 is configured to construct a complex multi-sealing path within the limited space of the accommodating cavity 110, thereby reducing the phenomenon of mud leaking from between two adjacent cemented carbide blocks 310, so that the sealing assembly 300 maintains stable sealing performance.

[0076] The following description will be made assuming that the number of cemented carbide blocks 310 is eight.

[0077] like Figure 6 As shown, when the eight cemented carbide blocks 310 are brought together, the first sealing portions 3141 on each cemented carbide block 310 are inclined planes extending along the extension direction of the cemented carbide block 310. The first sealing portions 3141 on each cemented carbide block 310 are tightly fitted together, forming a closed annular entity. The second sealing portions 3142 of two cemented carbide blocks 310 arranged along the X-direction are two identical planes that fit together. The second sealing portions 3142 of two cemented carbide blocks 310 adjacent to the same side of the two cemented carbide blocks 310 arranged along the X-direction are two identical planes that fit together. The two cemented carbide blocks 310 arranged along the Y-direction have triangular wedge-shaped structures, and the corresponding second sealing portions 3142 are straight lines. In this way, the abutting and fitting second sealing portions 3142 form a second sealing line 302 that extends along the diameter of the through-hole 120. That is, the second sealing line 302 extends along the Y-direction as shown.

[0078] Overall, the sealing assembly 300 constructs eight staggered sealing paths, which makes it difficult for mud to leak out of the wellhead through the sealing assembly 300, thereby reducing the risk of mud leakage.

[0079] Among them, the two carbide blocks 310 arranged along the Y direction can generate radial extrusion force in the annular array through the wedge-shaped profile, compressing the contact pressure of the second sealing parts 3142 of the two adjacent carbide blocks 310, which is beneficial to improving the overall structural stability and sealing performance of the sealing assembly 300.

[0080] Here, it can be understood that by forming the first sealing line 301 and the second sealing line 302, the contact pressure on the carbide block 310 can be evenly distributed, and the force can be evenly distributed under the external force of mud scouring, and local stress concentration is not easy to occur. The mud channel between the two through holes 120 can be effectively blocked to prevent the leakage of mud in the well.

[0081] It should be noted that when the number of cemented carbide blocks 310 is 4, 5, 6, etc., the specific arrangement and structural design can be adaptively set with reference to the above method, and this embodiment of the present application will not be further described.

[0082] It should also be noted that in some examples, the first sealing portion 3141 may include an inclined plane segment and at least one insertion segment disposed on the inclined plane segment. The insertion segment in one of two adjacent first sealing portions 3141 is a protrusion, while the insertion segment in the other is a groove that matches the protrusion. In this manner, the protrusion and the groove wall are precisely machined to match. Once the protrusion is inserted into the groove, the protrusion abuts against the groove wall, thereby aligning the two planar segments and forming the first sealing line 301.

[0083] certainly, Figure 6 When the second sealing portions 3142 of the two carbide blocks 310 arranged along the X direction shown in the figure are fitted together, the two second sealing portions 3142 are not limited to the same plane as mentioned above, and can also be designed with reference to the above structure. As long as it is ensured that the second sealing portions 3142 can abut and fit together to form a second sealing line 302, this application will not elaborate on this.

[0084] In other examples, the second sealing portions 3142 together form a spiral tooth (not shown in the figure), which extends spirally along the axial direction of the through hole 120. The spiral teeth are used to match and plug with the spiral tooth grooves on the circumferential side of the drill rod, so that the second sealing portions 3142 together embrace the drill rod; thereby blocking the two through holes 120.

[0085] In this way, when the annular blowout preventer is used in a scenario where there is a drill pipe in the well, the spiral teeth are matched and plugged into the spiral tooth grooves on the drill pipe, which is beneficial to improving the friction coefficient between the second sealing part 3142 and the drill pipe, enhancing the friction force of each second sealing part 3142 and the drill pipe, preventing the drill pipe from sliding, and forming a tighter sealing interface, thereby ensuring that the sealing assembly 300 can normally block the two through holes 120 and have a better sealing effect.

[0086] See Figure 1 、 Figure 3 and Figure 4 In some examples, the annular blowout preventer further includes a first sleeve 400, the piston member 200 is slidably mounted on the first sleeve 400, and the first sleeve 400 is coaxially arranged with the through hole 120; the piston member 200 has a first inclined surface 211 on a side facing the first sleeve 400, and the cemented carbide block 310 has a second inclined surface 311 on a side facing the piston member 200; the cemented carbide block 310 has a first side 312 and a second side 313 opposite to each other, the first side 312 is in contact with the first sleeve 400, and the second side 313 is in contact with the inner wall of the shell member 100.

[0087] The second inclined surface 311 is configured to slide along the first inclined surface 211 when the piston 200 is lifted or lowered, so as to move the corresponding cemented carbide block 310 toward or away from the axis of the through hole 120 , so that the cemented carbide blocks 310 gather together or move away from each other.

[0088] In this way, the first sleeve 400 provides additional guiding support for the piston 200, preventing it from shifting or tilting during the lifting process. By arranging the first side 312 to mate with the first sleeve 400 and the second side 313 to mate with the inner wall of the housing 100, the second inclined surface 311 slides along the first inclined surface 211 driven by the lifting and lowering of the piston 200, forming a stable three-sided limit structure for the cemented carbide blocks 310, ensuring smooth movement and controllable trajectory of the cemented carbide blocks 310, guiding the cemented carbide blocks 310 to move along a predetermined path, and enabling the cemented carbide blocks 310 to more accurately converge or move away from each other.

[0089] Specifically, the annular blowout preventer is as follows in the well to be drilled: Figure 3 The position status shown, Figure 3 The Z direction in the figure represents the direction of gravity. The first side 312 of the cemented carbide block 310 is located below the second side 313 along the Z direction on the opposite sides of the shell 100 , ie, the two sides of the shell 100 along the Z direction.

[0090] For example, the piston member 200 is slidably mounted on the first sleeve 400 and slidably positioned between the first sleeve 400 and the circumferential wall of the accommodating chamber 110. The first sleeve 400 and the circumferential wall of the accommodating chamber 110 can restrict the piston member 200's freedom in non-lifting directions, ensuring smooth lifting and lowering of the piston member 200 and preventing skewed swinging of the piston member 200 from causing asynchronous movement, jamming, or increased wear of the sealing assembly 300. The first sleeve 400 can be made of a wear-resistant material to extend its service life.

[0091] In a specific implementation, the first inclined surface 211 is a conical surface, and the second inclined surface 311 is an inclined surface matching the conical surface.

[0092] In this way, the lifting motion of the piston member 200 can be efficiently converted into radial movement of the carbide block 310 through the matching structure of the conical surface and the inclined surface; matching each carbide block 310 with the same conical surface is conducive to the synchronous movement and uniform force of each carbide block 310; the conical surface has a larger contact area, which helps to disperse pressure and reduce local wear.

[0093] For example, Figure 3 and Figure 4 As shown, the conical cavity surrounded by the conical surface has a small diameter end and a large diameter end; the piston member 200 is sleeved on the first sleeve 400, so that the first sleeve 400 is placed in the conical cavity, and the diameter of the first sleeve 400 matches the small diameter end. Overall, the piston member 200 is located on the outside of the first sleeve 400, and the shell member 100 is located on the outside of the piston member 200, so that the piston member 200 is slidably placed between the first sleeve 400 and the circumferential cavity wall of the accommodating cavity 110.

[0094] When the piston 200 rises, the first side 312 of the carbide block 310 is in contact with the first sleeve 400, and the second side 313 is in contact with the inner wall of the shell 100, thereby forming a bidirectional rigid limit for the carbide block 310 in the upper and lower directions through the shell 100 and the first sleeve 400, so as to completely constrain the axial displacement of the carbide block 310; at the same time, the sliding member 600 drives the carbide block 310 to move on the slide groove 212, which will cause the carbide block 310 to move away from the large diameter end and closer to the small diameter end relative to the piston. To this end, the sliding cooperation between the conical surface and the inclined surface is used to convert the lifting motion of the piston into radial displacement of the carbide block 310, so that the carbide block 310 moves toward the axis of the through hole 120, prompting the carbide blocks 310 to gather together, ensuring that the carbide blocks 310 can normally move away from the large diameter end and closer to the small diameter end.

[0095] Correspondingly, when the piston member 200 descends, the sliding member 600 drives the carbide block 310 to move on the slide groove 212, which will cause the carbide block 310 to move closer to the large diameter end and away from the small diameter end relative to the piston. The sliding cooperation between the conical surface and the inclined surface converts the lifting motion of the piston into radial displacement of the carbide block 310, causing the carbide block 310 to move away from the axis of the through hole 120, prompting the carbide blocks 310 to move away from each other, ensuring that the carbide blocks 310 can normally approach the large diameter end and away from the small diameter end.

[0096] See Figure 1 、 Figure 4 and Figure 7 In some embodiments, the first sleeve 400 includes a sleeve portion 410 and a limiting portion 420; the piston member 200 is slidably mounted on the sleeve portion 410; the limiting portion 420 is connected to the sleeve portion 410, and the limiting portion 420 is arranged around the circumference of the sleeve portion 410. The limiting portion 420 is configured to abut against the piston member 200 when the carbide blocks 310 gather together.

[0097] In this way, the first sleeve 400 abuts against the piston member 200 through the limiting portion 420 to achieve mechanical limiting of the piston member 200 and restrict the piston member 200 from continuing to rise, thereby effectively making the piston member 200 have better movement accuracy.

[0098] It can be understood that the limiting portion 420 is in contact with the piston member 200, that is, the limiting portion 420 is in contact with the first inclined surface 211. By processing the surface where the limiting portion 420 and the first inclined surface 211 are in contact with each other to match the first inclined surface 211, it is ensured that the piston member 200 can be more fully fitted with the limiting portion 420 after lifting and lowering, thereby achieving the stability of the mechanical limit; at the same time, the fitting area is designed with a smooth transition, which can avoid local stress concentration and ensure the positioning accuracy of the upward position of the piston member 200.

[0099] See Figures 3 to 6 In a specific example, the annular blowout preventer further includes at least three sliding members 600, which are connected to the carbide blocks 310 in a one-to-one correspondence. At least three sliding grooves 212 are spaced apart on the circumference of the piston member 200, and the sliding grooves 212 are located on the first inclined surface 211. The sliding members 600 are placed in the sliding grooves 212 in a one-to-one correspondence. The sliding members 600 are configured to move along the extension direction of the sliding grooves 212 when the piston member 200 is raised or lowered.

[0100] In this way, the sliding member 600 is embedded in the slide groove 212 to form a stable connection, which can prevent the carbide block 310 from shifting or falling off due to uneven force, and can ensure the stable operation of the sealing assembly 300 when encountering transient high pressure or vibration during the drilling process; at the same time, the matching setting of the sliding member 600 and the slide groove 212 simplifies the disassembly and assembly between the carbide block 310 and the piston member 200, making it convenient for the operator to replace any carbide block 310.

[0101] Furthermore, through the cooperation between the slide groove 212 and the sliding member 600, the wear between the carbide block 310 and the piston member 200 during the sliding process can be reduced, and the carbide block 310 can be guided to move according to the set path, avoiding the sealing failure problem caused by offset or jamming of any carbide block 310.

[0102] It can be understood that the extending direction of the sliding groove 212 is consistent with the inclination direction of the first inclined surface 211 .

[0103] In this way, the lifting motion of the piston member 200 can be more directly converted into the radial movement of the cemented carbide block 310 , thereby reducing unnecessary energy loss and improving the movement efficiency of the cemented carbide block 310 .

[0104] At the same time, the frictional force experienced by the carbide block 310 as it moves along the chute 212 can be more evenly distributed, reducing the risk of localized excessive wear and extending its service life. Furthermore, the carbide block 310 can be ensured to remain stable during movement, reducing the risk of deflection or sticking, and improving the overall movement accuracy of the piston 200 and carbide block 310.

[0105] In some embodiments, the sliding member 600 includes a slider connected to the corresponding carbide block 310 , and the slider is placed in the slide groove 212 ; or,

[0106] The sliding member 600 includes a second slider 610 and a pin 620 located in the slide groove 212. The second slider 610 is connected to the corresponding carbide block 310. The second slider 610 is provided with a socket. The pin rod 6212 of the pin shaft 620 is transitionally plugged into the socket so that the pin shaft cap 6211 of the pin shaft 620 contacts one side of the second slider 610; the pin rod 6212 is provided with a groove 6213 on the peripheral side adjacent to the other side of the second slider 610, and a retaining spring 6221 is provided on the groove 6213. A gasket 6222 is sleeved on the retaining spring 6221, and the gasket 6222 contacts the other side of the second slider 610.

[0107] When the sliding member 600 includes a slider, the inner groove walls on both sides of the notch can provide a limiting and guiding function for the slider to prevent the first slider from falling out or getting stuck, thereby improving the reliability of the assembly of the carbide block 310 and the piston.

[0108] For example, by placing a slider within the chute 212, when the piston descends, the chute 212 exerts a pulling force on the slider perpendicular to the chute body, causing the slider to move diagonally upward along the chute 212. The carbide block 310, constrained by the first sleeve 400 and the inner wall of the housing 100, moves horizontally outward, that is, away from the axis of the through hole 120. In this way, the carbide block 310 can move relative to the piston in the aforementioned direction, toward the larger diameter end and away from the smaller diameter end.

[0109] When the sliding member 600 includes the second sliding block 610 and the pin 620, rolling friction occurs between the pin 620 and the slide groove 212 to reduce the friction coefficient therebetween, thereby reducing local fatigue damage to the pin 620 and the slide groove 212 caused by long-term sliding. At the same time, the carbide block 310 is made easier to move, thereby reducing the driving force required to raise and lower the piston member 200, making the overall use of the annular blowout preventer more efficient.

[0110] Furthermore, when the carbide block 310 moves and the second inclined surface 311 slides along the first inclined surface 211, the pin shaft 620 in the slide groove 212 is subjected to shear load, and the retaining spring 6221 and the gasket 6222 jointly prevent the pin shaft 620 from axial movement, thereby avoiding the second slider 610 from deflecting or falling off during the synchronous movement in the slide groove 212, so that the pin shaft 620 as a whole can play a better positioning role for the second slider 610.

[0111] See Figure 1 、 Figure 3 and Figure 4 In some examples, the support assembly further includes a second sleeve 500, the second sleeve 500 is located in the accommodating cavity 110, and the first sleeve 400 is located in the second sleeve 500, the second sleeve 500 is coaxially arranged with the first sleeve 400; the piston member 200 is slidingly connected to the second sleeve 500.

[0112] In this way, the second sleeve 500 provides limiting and auxiliary support for the piston member 200, and the double sleeve structure formed by the second sleeve 500 and the first sleeve 400 provides the piston member 200 with a wider support surface and double guidance, which is conducive to making the lifting and lowering action of the piston member 200 more stable and reliable.

[0113] For example, the second sleeve 500 is coaxially arranged with the first sleeve 400 to ensure the overall structural symmetry of the annular blowout preventer and the consistency of the movement of the cemented carbide blocks 310 driven by the piston 200 .

[0114] See Figure 1 and Figure 10 In a specific implementation, the piston member 200 includes a fitting portion 210 and a sliding portion 220 connected to the outer peripheral wall of the fitting portion 210; the inner peripheral wall of the fitting portion 210 forms a first inclined surface 211, the fitting portion 210 is slidably sleeved on the first sleeve 400, and the sliding portion 220 is slidably connected to the second sleeve 500.

[0115] In this way, the carbide block 310 is driven to move by the matching portion 210 , and the sliding portion 220 cooperates with the second sleeve 500 to achieve guidance, so that the structural design of the piston member 200 is more reasonable.

[0116] The matching portion 210 may be a cone structure, and the sliding portion 220 may be designed as follows: Figure 9 The ring structure shown.

[0117] For example, the mating portion 210 and the sliding portion 220 can be integrally molded. This term refers to the process of molding the entire component in a single mold. Compared to traditional, step-by-step manufacturing processes, integral molding simplifies the manufacturing process, offers high precision and efficiency, and reduces production costs. In this way, integrally molding the mating portion 210 and the sliding portion 220 prevents a loose connection between the two, preventing gaps from forming between them and compromising the structural strength of the piston member 200.

[0118] Furthermore, the one-piece molding can avoid the connection between the matching portion 210 and the sliding portion 220 and the additional processing process, which is beneficial to improving production efficiency and reducing production costs.

[0119] See Figure 1 、 Figure 10 and Figure 11 In the specific example, the sliding portion 220 includes a sliding section 221 and a contact section 222; the sliding section 221 is connected to the outer peripheral wall of the mating portion 210, and a sliding cavity 2211 with an opening 2212 on one side is opened on the sliding section 221. The sliding cavity 2211 matches the second sleeve 500, and the sliding section 221 is slidably inserted into the second sleeve 500 through the sliding cavity 2211; the contact section 222 is connected to the sliding section 221, and the contact section 222 is located between the sliding section 221 and the peripheral cavity wall of the accommodating cavity 110.

[0120] The contact section 222 is configured to contact the hydraulic oil when the hydraulic device in the well control system injects hydraulic oil into the accommodating chamber 110, so as to drive the sliding section 221 to slide relative to the second sleeve 500 under the push of the hydraulic oil, thereby causing the matching portion 210 to rise and fall.

[0121] In this way, the contact section 222 withstands the pressure of the hydraulic oil, so that the piston part 200 responds to the hydraulic pressure faster and starts the lifting action more sensitively; the sliding section 221 forms a stable sliding guide structure with the second sleeve 500 through the sliding cavity 2211, which can ensure that the piston part 200 rises and falls smoothly.

[0122] Among them, such as Figure 10 and Figure 11 As shown, the sliding section 221 may be an annular shell structure, and the contact section 222 may be an annular plate structure.

[0123] When the piston 200 is lifted or lowered, the accommodating chamber 110 can be divided into a first sub-accommodating chamber 111 and a second sub-accommodating chamber 112 with adjustable volumes by the contact section 222. Figure 1 The Z direction shown in FIG is located above the second sub-accommodating chamber 112. Thus, when the piston 200 needs to be driven to rise, hydraulic oil is injected into the second sub-accommodating chamber 112 through the hydraulic device, so that the liquid level of the hydraulic oil in the second sub-accommodating chamber 112 is increased to push the contact section 222 to drive the sliding section 221 to slide upward relative to the second sleeve 500, so that the piston 200 is moved upward. Figure 3 The position shown changes to Figure 4 When the piston member 200 needs to be driven downward, hydraulic oil is injected into the first sub-accommodating chamber 111 through the hydraulic device, so that the liquid level of the hydraulic oil in the first sub-accommodating chamber 111 is increased to push the contact section 222 to drive the sliding section 221 to slide downward relative to the second sleeve 500, so that the piston member 200 is moved downward. Figure 4 The position shown changes to Figure 3 Position shown.

[0124] See Figure 1 、 Figure 5 、 Figure 6 and Figure 12 In some examples, the shell member 100 includes a shell portion 101 and a cover portion 102 that is detachably mounted on the shell portion 101; the shell portion 101 and the cover portion 102 together form a accommodating cavity 110, and both the shell portion 101 and the cover portion 102 are provided with a through hole 120; the cover portion 102 has a contact portion 1021 on the side facing the shell portion 101, the contact portion 1021 is connected to the through hole 120, and the side of the contact portion 1021 facing away from the cover portion 102 is used to fit with the second side 313, and the circumferential side of the contact portion 1021 has a third inclined surface 1022 that matches the first inclined surface 211, and the third inclined surface 1022 is used to abut against part of the first inclined surface 211 when the cemented carbide blocks 310 gather together.

[0125] In this way, the operator can easily remove the cover setting part 102 to perform maintenance and replacement of the hard alloy blocks 310 and the piston member 200 in the accommodating cavity 110, and the maintenance efficiency is higher; meanwhile, the assembly efficiency of the operator for the annular blowout preventer as a whole is improved.

[0126] In combination Figure 4 As shown, when the piston rises, the hard alloy blocks 310 are gathered together, and the third inclined surface 1022 on the periphery of the abutting part 1021 abuts against the part of the first inclined surface 211 of the piston member 200, so as to form a rigid stop for the piston member 200, and the piston member 200 is limited to continue to rise, and the piston member 200 has better movement precision.

[0127] Specifically, the third inclined surface 1022 is a conical surface, and the abutting part 1021 can be a circular truncated cone, and the arc-shaped inclined surface on the periphery of the circular truncated cone is the third inclined surface 1022. The circular truncated cone structure is simple and convenient to manufacture; the cover setting part 102 and the abutting part 1021 can be integrally formed to ensure better connection reliability therebetween.

[0128] In specific implementation, during the lifting of the piston member 200, the first side 312 of the hard alloy block 310 is in sliding contact with the first sleeve 400, and the second side 313 is in sliding contact with the inner wall of the housing member 100, in order to reduce the abrasion of the hard alloy block 310, in some examples, the first side 312 is coated with a wear-resistant coating.

[0129] In this way, the first side 312 and the second side 313 of the hard alloy block 310 are subjected to surface strengthening treatment, which is beneficial to reduce the abrasion of the hard alloy block 310 and improve the service life of the hard alloy block 310.

[0130] For example, the wear-resistant coating includes at least one of tungsten carbide, titanium nitride, aluminum titanium nitride, and titanium carbonitride.

[0131] The tungsten carbide has high hardness and wear resistance, can meet the application requirements of high friction conditions; the titanium nitride has good oxidation resistance, low friction coefficient, and excellent thermal stability; the aluminum titanium nitride has good high-temperature resistance and is suitable for high-temperature operating environments; the titanium carbonitride has good comprehensive hardness and toughness, and has wear resistance and impact resistance.

[0132] The embodiment of the present application also provides a well control system, which includes a system body and an annular blowout preventer as in any of the above embodiments arranged on the system body.

[0133] The system includes a drill pipe and a hydraulic device (not shown). The annular BOP is installed in a well. The drill pipe sequentially passes through two through-holes 120 in the housing 100 of the annular BOP, so that it is partially located in the well. The hydraulic device is used to inject hydraulic oil into the accommodating chamber 110 of the housing 100 to move the piston 200 upward and downward. Driven by the rising and falling piston 200, the carbide blocks 310 of the annular BOP are designed to converge to embrace the drill pipe, closing the wellhead, or move away from each other, opening the wellhead.

[0134] The overall structure and working principle of the annular blowout preventer are the same as those in the aforementioned embodiment and will not be described in detail here.

[0135] The well control system of the embodiment of the present application is used to maintain the balance between the bottom hole pressure and the formation pressure by controlling the drilling fluid density, the annular space pressure, the annular blowout preventer action, etc.

[0136] As mentioned above, the housing 100 is provided with an interface for connecting the hydraulic pipeline of the hydraulic device, so that the hydraulic device can introduce the hydraulic oil into the accommodating cavity 110 through the hydraulic pipeline to push the piston 200 up and down.

[0137] Furthermore, the drill rod has a cylindrical body, and the second sealing portion 3142 of each cemented carbide block 310 can be configured as a curved surface with a uniform curvature. When the cemented carbide blocks 310 are brought together, the curved surfaces form a circular groove that matches the cylindrical body. The circular groove connects the two through-holes 120 in the housing 100, and the groove wall of the circular groove closely mates with the circumferential sidewalls of the cylindrical body. In this way, the curved surfaces closely mate with the circumferential sidewalls of the drill rod, allowing the second sealing portions 3142 to collectively embrace the drill rod, thereby blocking the two through-holes 120.

[0138] Alternatively, based on the above, the hardness of the cemented carbide blocks 310 may be higher than that of the drill rod, and the curved surfaces may be provided with raised, fine threads. In this way, when the cemented carbide blocks 310 are brought together, forming a circular groove that matches the cylindrical rod, the fine threads can be actively embedded in the drill rod, ensuring a tighter fit between the groove walls and the cylindrical rod's circumference.

[0139] Of course, in other examples, the drill pipe has spiral tooth grooves that match the spiral teeth surrounded by the second sealing parts 3142 of each cemented carbide block 310. When the cemented carbide blocks 310 gather together, the spiral tooth grooves on the circumferential side of the drill pipe are plugged into the spiral teeth, so that the second sealing parts 3142 can embrace the drill pipe together; at the same time, the first sealing parts 3141 of adjacent cemented carbide blocks 310 are abutted and fitted to form at least three first sealing lines 301, thereby blocking the two through holes 120 and closing the wellhead of the well.

[0140] The hydraulic device is used to provide power for the annular blowout preventer, and can support remote operation to ensure rapid response to emergencies. It should be noted that the specific structure of the hydraulic device can be designed with reference to existing technologies, and this embodiment of the application will not be described in detail.

[0141] Exemplarily, the system body may also include a drilling fluid circulation device, a gate blowout preventer, a well-killing and throttling manifold device and a monitoring feedback device; the drilling fluid circulation device is used to prepare and circulate drilling fluid with a specific density, and control the bottom hole pressure by adjusting the mud density; the annular blowout preventer and the gate blowout preventer are used to quickly seal the well in the event of overflow or well kick, to prevent the blowout from getting out of control; the well-killing and throttling manifold is connected to the annular blowout preventer and the gate blowout preventer, and is used to implement throttling and blowout or well-killing operations in the shut-in state to restore the pressure balance in the well; the monitoring feedback device can be used to collect parameters such as wellhead vertical pressure, casing pressure, mud pool level, gas concentration, etc.

[0142] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. An annular blowout preventer, characterized in that: include: A shell member, wherein the shell member has an accommodating cavity therein, and through holes communicating with the accommodating cavity are formed on opposite sides of the shell member; a piston member, the piston member being located in the accommodating cavity and being used for lifting and lowering between the two through holes; A sealing assembly comprises at least three carbide blocks, each of which is slidably connected to the piston member, and has a first sealing portion and a second sealing portion, wherein the first sealing portion is arranged toward the adjacent carbide block, and the second sealing portion is arranged away from the piston member; each carbide block is configured to gather together or move away from each other under the drive of the piston member to rise and fall; wherein, when gathering together, each adjacent first sealing portion abuts against each other, and each second sealing portion abuts against each other or is used to jointly embrace the drill pipe in the well control system passing through the through hole to block the two through holes; when moving away from each other, the first sealing portion and the second sealing portion slide following the corresponding carbide block to connect the two through holes.

2. The annular blowout preventer according to claim 1, characterized in that: The number of the cemented carbide blocks is at least four; Adjacent first sealing portions abut against each other to form at least four first sealing lines, and the first sealing lines extend obliquely along the extension direction of the corresponding cemented carbide block; The second sealing parts abut against each other to form a second sealing line extending along the diameter direction of the through hole, or the second sealing parts jointly form a spiral tooth, and the spiral tooth extends spirally along the axial direction of the through hole. The spiral tooth is used to match and plug with the spiral tooth grooves on the circumferential side of the drill rod, so that the second sealing parts jointly embrace the drill rod; to block the two through holes.

3. The annular blowout preventer according to claim 1, characterized in that: It also includes a first sleeve, the piston member is slidably sleeved on the first sleeve, and the first sleeve is coaxially arranged with the through hole; The piston member has a first inclined surface on a side facing the first sleeve, and the carbide block has a second inclined surface on a side facing the piston member; the carbide block has a first side and a second side opposite to each other, the first side is in contact with the first sleeve, and the second side is in contact with the inner wall of the housing member; The second inclined surface is configured to slide along the first inclined surface when the piston is lifted and lowered, so as to move the corresponding cemented carbide block toward or away from the axis of the through hole, so that the cemented carbide blocks gather together or move away from each other.

4. The annular blowout preventer according to claim 3, characterized in that: The first sleeve comprises: a sleeve portion, on which the piston member is slidably sleeved; A limiting portion is connected to the sleeve portion and is arranged around the circumference of the sleeve portion. The limiting portion is configured to abut against the piston member when the cemented carbide blocks are brought together.

5. The annular blowout preventer according to claim 3, characterized in that: The piston further comprises at least three sliding members, each of which is connected to the cemented carbide block in a one-to-one correspondence; at least three sliding grooves are spaced apart on the circumference of the piston, and the sliding grooves are located on the first inclined surface; The sliding members are placed in the sliding grooves in a one-to-one correspondence, and the sliding members are configured to move along the extending direction of the sliding groove when the piston member is raised or lowered.

6. The annular blowout preventer according to claim 5, characterized in that: The sliding member includes a slider, the slider is connected to the corresponding carbide block, and the slider is placed in the slide groove; or, The sliding part includes a second slider and a pin located in the slide groove, the second slider is connected to the corresponding carbide block, the second slider is provided with a socket, the pin rod of the pin shaft is transitionally plugged into the socket so that the pin shaft cap of the pin shaft contacts one side of the second slider; a groove is provided on the peripheral side of the pin rod adjacent to the other side of the second slider, a retaining ring is provided on the groove, a gasket is sleeved on the retaining ring, and the gasket contacts the other side of the second slider.

7. The annular blowout preventer according to any one of claims 3 to 6, characterized in that: Also included is a second sleeve, the second sleeve is located in the accommodating cavity, the first sleeve is located in the second sleeve, and the second sleeve is coaxially arranged with the first sleeve; The piston is slidably connected to the second sleeve.

8. The annular blowout preventer according to any one of claims 3 to 6, characterized in that: The housing member comprises a housing portion and a cover portion detachably mounted on the housing portion; the housing portion and the cover portion together enclose the accommodating cavity, and the housing portion and the cover portion are both provided with the through hole; The cover portion has an abutment portion on one side facing the shell portion, the abutment portion is connected to the through hole, the abutment portion is used to fit with the second side on the side facing away from the cover portion, and the circumferential side of the abutment portion has a third inclined surface matching the first inclined surface, and the third inclined surface is used to abut against part of the first inclined surface when the cemented carbide blocks are gathered together.

9. The annular blowout preventer according to any one of claims 3 to 6, characterized in that: The first side and the second side are both coated with a wear-resistant coating.

10. A well control system, characterized in that: A system comprising a system body and an annular blowout preventer according to any one of claims 1 to 9, arranged on the system body; the system body comprising a drill pipe and a hydraulic device; the annular blowout preventer is configured to be disposed in a well, the drill pipe sequentially passing through two through holes on a housing member of the annular blowout preventer so as to be partially located in the well; The hydraulic device is used to inject hydraulic oil into the accommodating cavity of the shell member to move the piston member up and down. The carbide blocks of the annular blowout preventer are used to gather together to embrace the drill pipe under the drive of the lifting of the piston member to close the wellhead of the well; or move away from each other to open the wellhead of the well.

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