A pipe string rams seal assembly for a blowout preventer

Abstract

The utility model discloses a pipe column sluice plate sealing assembly for blowout preventer relates to blowout preventer technical field, and the sluice plate body has recess, front seal installation groove and top seal installation groove, including: install the sealing pad iron structure in front seal installation groove, including sealing rubber, the strip gasket plate no.

Description

Technical Field

[0001] This utility model relates to the field of blowout preventer technology, and in particular to a tube column gate sealing assembly for a blowout preventer. Background Technology

[0002] As oil exploration and development expands into deeper formations and complex marine environments, the importance of ultra-high pressure high-temperature blowout preventers (UHPPs) is becoming increasingly prominent. Their development trends focus on higher pressure ratings, superior high-temperature resistance, and enhanced reliability. As a critical safety device in oil drilling operations, UHPPs bear the heavy responsibility of precisely controlling wellhead pressure and preventing blowouts under extremely harsh conditions. They are of paramount importance for ensuring the safety of drilling personnel, reducing environmental pollution, and ensuring the effective development of oil and gas resources.

[0003] As the core sealing element of ultra-high pressure and high temperature blowout preventers (BOPs), the gate seal's performance directly determines the BOP's sealing effect. Under the harsh conditions of ultra-high pressure and high temperature, the gate seal faces numerous challenges. High temperatures cause significant changes in the molecular structure of rubber sealing materials, leading to a sharp increase in fluidity and a significant decrease in strength. This change in properties makes the rubber highly susceptible to extrusion, leakage, or even breakage from the sealing gap under pressure, ultimately resulting in seal failure. For example, in drilling operations of some deep geothermal wells or ultra-deep wells, where downhole temperatures often exceed 200°C and pressures exceed 175 MPa, conventional rubber seals will experience severe deformation and extrusion problems within a short time under such high temperature and pressure conditions. Simultaneously, the ultra-high pressure environment places extremely stringent requirements on the metal components of the gate seal. Under ultra-high pressure, traditional sealing structures are prone to deformation of metal sealing components due to excessive compression. This deformation may damage the sealed tubing, affecting the structural integrity and sealing performance of the tubing string. Furthermore, under the combined effects of high pressure and high temperature, the sealing components also face problems such as corrosion and accelerated wear, further weakening their sealing performance and service life.

[0004] Chinese patent (authorization announcement number CN 111094692 B, authorization announcement date 2023.07.25) discloses a blowout preventer gate packer assembly, specifically a gate packer assembly suitable for single use, which includes a packing material formed of metal material, the metal material being fully deformable to collapse around the outer periphery of the drill pipe to seal the blowout preventer opening. It can be seen that its technical solution uses metal packing to achieve high-temperature sealing to a certain extent, but since the packing is not an elastomer, it can only be used once, and the gate or the packing material of the gate needs to be replaced after use.

[0005] Therefore, how to design a gate valve sealing assembly for blowout preventers that can adapt to high-pressure and high-temperature environments, effectively prevent severe deformation and extrusion of rubber seals, and has the characteristics of improved sealing effect and good durability is a problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0006] In view of this, the present invention proposes a tube column gate sealing assembly for blowout preventers, which aims to solve the technical problem that the above-mentioned traditional blowout preventer gate sealing structure is prone to extrusion deformation under high temperature and high pressure conditions, resulting in reduced sealing performance.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] This utility model provides a gate valve sealing assembly for a blowout preventer (BOP) tube string. The front end face of the gate valve body has a recess for accommodating the tube string and a front sealing mounting groove extending to both the left and right sides. Its top end face has a top sealing mounting groove extending to both the left and right sides. It includes:

[0009] A sealing pad structure is installed in the front sealing mounting groove; the sealing pad structure includes sealing rubber, a strip-shaped pad 1 embedded at the top of the sealing rubber, a strip-shaped pad 2 embedded at the bottom of the sealing rubber, a semi-annular elastic plate 1 parallel to the lower end face of the strip-shaped pad and embedded in the sealing rubber, and a semi-annular elastic plate 2 parallel to the upper end face of the strip-shaped pad 2 and embedded in the sealing rubber.

[0010] A concave surface is formed in the middle of the front end of the sealing rubber; the front ends of the strip-shaped pad 1 and the strip-shaped pad 2 are arranged corresponding to the front end face of the sealing rubber and each has a concave surface 2 corresponding to one of the concave surfaces; the inner peripheral walls of the semi-annular elastic plate 1 and the semi-annular elastic plate 2 are both corresponding to the concave surface 1; the concave surface 1, the concave surface 2 and the inner peripheral wall have the same outline and together constitute a sealing concave surface for pressing against the outer peripheral wall of the sealing tube column.

[0011] A top seal is installed in the top seal mounting groove.

[0012] This invention relates to a gate valve sealing assembly for a blowout preventer. During gate valve pressure sealing, the sealing concave surface effectively fills the gaps around the outer periphery of the tube column, preventing the sealing rubber from being squeezed out under high temperatures. Semi-annular elastic plates one and two are tightly clamped to the outer wall of the tube column, while strip-shaped pads one and two further constrain and support the sealing rubber, effectively reducing the rubber's fluidity under high temperatures and improving sealing strength and stability. This comprehensively controls the rubber from being squeezed out and broken due to increased fluidity and weakened strength under high temperatures, thus preventing seal failure. The gate valve sealing assembly of this invention can be reused multiple times while maintaining good sealing performance and exhibits high durability.

[0013] As a further improvement to the above technical solution, the front ends of the sealing rubber, the first strip pad, the second strip pad, the first semi-annular elastic plate, and the second semi-annular elastic plate can all extend out of the front sealing mounting groove and enter the recess; there is a preset distance between the rear end faces of the first strip pad and the second strip pad and the rear end face of the sealing rubber.

[0014] The beneficial effects of the above technical solution are as follows: During the gate pressure sealing process, as the concave surfaces of strip pad one and strip pad two gradually press against the outer peripheral wall of the pipe column, they will gradually retract into the front sealing installation groove and align with the inner peripheral wall of the concave portion. Finally, the entire sealing concave surface aligns with the inner peripheral wall of the concave portion. Under the elastic restoring force of the sealing rubber, the strip pad one, strip pad two, semi-annular elastic plate one, and semi-annular elastic plate two can always maintain the tight clamping state of the strip pad one, strip pad two, semi-annular elastic plate one, and semi-annular elastic plate two against the outer peripheral wall of the pipe column, thereby ensuring the sealing and anti-extrusion effect.

[0015] As a further improvement to the above technical solution, both the first semi-annular elastic plate and the second semi-annular elastic plate are provided with connecting grooves on their outer peripheral sides.

[0016] The beneficial effects of the above technical solution are: during the vulcanization and molding of the sealing rubber, it can flow into the connecting groove to achieve a tight connection between the semi-annular elastic plate one, the semi-annular elastic plate two, and the sealing rubber, making it less prone to detachment. The connecting groove can also change the mechanical properties of the semi-annular elastic plate one and the semi-annular elastic plate two, reducing their stiffness and allowing for precise control of deformation under ultra-high sealing pressure. This ensures the sealing effect while avoiding extrusion damage to the sealed tubular column.

[0017] As a further improvement to the above technical solution, the left and right ends of the front sealing mounting groove correspond one-to-one with the left and right ends of the top sealing mounting groove and are connected through an overlapping channel provided inside the gate body; the top seal and the sealing rubber are connected at the connection between the front sealing mounting groove and the top sealing mounting groove to form a sealing strip structure.

[0018] The beneficial effects of the above technical solution are as follows: the sealing rubber, as the main component of the front seal, is connected to the top seal through an overlap channel, which is cleverly placed inside the gate body. This effectively guides the flow path of the sealing fluid, reduces rubber loss during the flow process, and improves the uniformity of the pressure distribution of the sealing fluid. When performing gate pressure sealing, the amount of rubber at the overlap position between the top seal and the front seal can be increased, enhancing the stability and reliability of the seal and further improving the overall sealing performance.

[0019] As a further improvement to the above technical solution, both ends of the first strip pad and the second strip pad are bent and embedded in the sealing rubber to form a flow rubber limiting part.

[0020] The beneficial effects of the above technical solution are as follows: the left and right ends (i.e. the two ends in the length direction) of the strip pad 1 and strip pad 2 are bent and embedded in the sealing rubber, which can effectively constrain the flow of rubber in the left and right directions of the gate body. Together with the semi-annular elastic plate 1 and semi-annular elastic plate 2, it can effectively fill the gaps in all directions and prevent extrusion. This comprehensively controls the problem of rubber being squeezed out of the gaps and broken due to increased fluidity and weakened strength under the influence of high temperature, thus avoiding the problem of sealing failure.

[0021] As a further improvement to the above technical solution, the sealing rubber is vulcanized and tightly bonded together with the first strip pad, the second strip pad, the first semi-annular elastic plate, and the second semi-annular elastic plate during vulcanization and molding.

[0022] The beneficial effects of the above technical solution are: the sealing rubber is tightly bonded to strip pad one, strip pad two, semi-annular elastic plate one and semi-annular elastic plate two through vulcanization, which can prevent detachment and improve sealing stability and durability.

[0023] As a further improvement to the above technical solution, both the first semi-annular elastic plate and the second semi-annular elastic plate are metal plates with a hardness lower than that of the column to be sealed.

[0024] The beneficial effects of the above technical solution are: by precisely controlling the composition of the materials and optimizing the processing technology, the strength of the semi-annular elastic plate one and the semi-annular elastic plate two can be effectively reduced, making their hardness lower than that of the tube column to be sealed, making them easier to deform, and preventing damage to the tube body to be sealed due to excessive compression when sealing under ultra-high pressure.

[0025] As can be seen from the above technical solution, compared with the prior art, the present invention discloses a gate valve sealing assembly for a blowout preventer, which has the following advantages and beneficial effects:

[0026] 1. The sealing gasket structure of this utility model effectively solves the problem of extrusion and damage of sealing rubber under ultra-high pressure and high temperature environment through the innovative design and synergistic effect of embedded strip gasket and semi-circular elastic plate. It greatly improves the reliability and durability of gate seal, significantly reduces the risk of seal failure, and provides more reliable safety guarantee for oil and gas extraction operations.

[0027] 2. The semi-annular elastic plate and the sealing rubber of this utility model are connected by a specially designed groove, which realizes a high-strength connection between the semi-annular elastic plate and the rubber. Furthermore, by optimizing the mechanical properties of the semi-annular elastic plate, it can be made to have a certain elastic deformation capacity, so that the deformation can be precisely controlled under ultra-high pressure sealing. This ensures the sealing effect, avoids damage to the sealed pipe, and improves the service life and operating efficiency of the equipment.

[0028] 3. The unique overlapping channel design of the top seal and the front seal of this utility model, through the optimization of the flow path of the sealing fluid, increases the amount of rubber at the front end of the top seal while reducing rubber loss, thereby improving the stability and reliability of the sealing performance. It can better adapt to the complex working conditions under ultra-high pressure and high temperature environments, effectively reduce safety hazards in the oil and gas extraction process, and has significant economic and social benefits. It also has broad application prospects in the field of blowout preventer technology. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0030] Figure 1 This utility model presents a three-dimensional structural schematic diagram of a tubular gate sealing assembly for a blowout preventer.

[0031] Figure 2 This utility model provides a three-dimensional schematic diagram of the gate body structure of a pipe column gate sealing assembly for a blowout preventer.

[0032] Figure 3 This utility model provides a three-dimensional schematic diagram of the sealing gasket structure of a pipe column gate sealing assembly for a blowout preventer.

[0033] Figure 4 This utility model discloses a semi-annular elastic plate structure of a pipe column gate sealing assembly for a blowout preventer.

[0034] In the diagram: 1. Gate body; 11. Recess; 12. Front seal mounting groove; 13. Top seal mounting groove; 14. Overlapping channel; 2. Sealing pad structure; 21. Sealing rubber; 211. Recess one; 22. Strip pad one; 221. Recess two; 23. Strip pad two; 24. Semi-annular elastic plate one; 241. Inner peripheral wall; 242. Connecting groove; 25. Semi-annular elastic plate two; 26. Sealing concave surface; 3. Top seal. Detailed Implementation

[0035] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0036] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0037] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0038] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0039] According to the embodiments of this utility model, such as Figures 1 to 4As shown, a gate valve sealing assembly for a blowout preventer has a gate valve body 1 with a recess 11 on the front end face for accommodating the tube string and a front sealing mounting groove 12 extending to the left and right sides, and a top sealing mounting groove 13 extending to the left and right sides on its top end face; it includes: a sealing gasket structure 2 and a top seal 3.

[0040] The sealing pad structure 2 is installed in the front sealing mounting groove 12; the sealing pad structure 2 includes sealing rubber 21, a strip-shaped pad 22 embedded at the top of the sealing rubber 21, a strip-shaped pad 23 embedded at the bottom of the sealing rubber 21, a semi-annular elastic plate 24 parallel to the lower end face of the strip-shaped pad 22 and embedded in the sealing rubber 21, and a semi-annular elastic plate 25 parallel to the upper end face of the strip-shaped pad 23 and embedded in the sealing rubber 21.

[0041] A concave surface 211 is formed at the middle of the front end of the sealing rubber 21; the front ends of the strip pad 22 and the strip pad 23 are arranged corresponding to the front end face of the sealing rubber 21, and a concave surface 221 is formed at the corresponding concave surface 211; the inner peripheral wall surfaces 241 of the semi-annular elastic plate 24 and the semi-annular elastic plate 25 are corresponding to the concave surface 211; the concave surface 211, the concave surface 221 and the inner peripheral wall surface 241 have the same outline and together constitute a sealing concave surface 26 for pressing against the outer peripheral wall of the sealing tube column.

[0042] The top seal 3 is installed in the top seal mounting groove 13.

[0043] This embodiment of a blowout preventer (BOP) gate valve sealing assembly utilizes a sealing concave surface 26 that effectively fills the gaps around the outer periphery of the tube column during gate valve pressure sealing. This prevents the sealing rubber 21 from being squeezed out of the gaps under high temperatures. Semi-annular elastic plates 24 and 25 are tightly bound to the outer periphery of the tube column. Strip pads 22 and 23 further constrain and stabilize the sealing rubber 21, effectively reducing the fluidity of the rubber under high temperatures and improving sealing strength and stability. This comprehensively controls the rubber from being squeezed out and damaged due to increased fluidity and weakened strength under high temperatures, thus preventing seal failure. The tube column gate valve sealing assembly of this invention can be reused multiple times while maintaining good sealing performance and exhibits high durability.

[0044] In some embodiments, the front ends of the sealing rubber 21, strip pad 1 22, strip pad 23, semi-annular elastic plate 1 24 and semi-annular elastic plate 25 can all extend out of the front sealing mounting groove 12 and enter the recess 11; there is a preset distance between the rear end face of strip pad 1 22 and strip pad 23 and the rear end face of sealing rubber 21.

[0045] During the gate pressure sealing process, as the concave surfaces 221 of strip pad 1 22 and strip pad 23 gradually press against the outer peripheral wall of the pipe column, they gradually retract into the front sealing mounting groove 12 and align with the inner peripheral wall of the recess 11. Finally, the sealing concave surface 26 is aligned with the inner peripheral wall of the recess 11. Under the elastic restoring force of the sealing rubber 21, the strip pad 1 22, strip pad 23, semi-annular elastic plate 1 24, and semi-annular elastic plate 25 can always maintain a precise fit and tight clamping state against the outer peripheral wall of the pipe column, forming a multi-layer elastic clamping structure, thereby ensuring the sealing and anti-extrusion effect.

[0046] Specifically, the preset distance between the rear end faces of strip pad 1 22 and strip pad 23 and the rear end face of sealing rubber 21 can be designed according to the elastic force requirements. This preset distance should be greater than the distance by which strip pad 1 22 and strip pad 23 extend beyond the opening of the front sealing mounting groove 12 along its depth direction. This ensures that after strip pad 1 22 and strip pad 23 abut against the pipe column, their front ends can retract into the front sealing mounting groove 12. The size of the preset distance also determines the contact force between strip pad 1 22 and strip pad 23 and the pipe column.

[0047] Specifically, the concave surface 211 of the sealing rubber 21, the concave surface 221 of the strip pad 22 and the strip pad 23, and the inner peripheral walls of the semi-annular elastic plate 24 and the semi-annular elastic plate 25 are all arc-shaped surfaces adapted to the outer peripheral wall of the pipe column. The semi-annular elastic plate 24 and the semi-annular elastic plate 25 can press against the outer peripheral wall of the pipe column under the elastic restoring force of the sealing rubber 21.

[0048] Specifically, when the tubing is cylindrical, the recess 11 can be designed as a semi-cylindrical shape with the same radius as the tubing. The inner circumferential walls of the concave surface 211 of the sealing rubber 21, the concave surface 221 of the strip pad 22 and the strip pad 23, and the semi-annular elastic plate 24 and the semi-annular elastic plate 25 can be designed to have the same radius as or slightly smaller than that of the recess 11 of the gate body 1. The radius of the sealing recess 26, which is formed by the concave surface 211 of the sealing rubber 21, the concave surface 221 of the strip pad 22 and the strip pad 23, and the inner circumferential walls of the semi-annular elastic plate 24 and the semi-annular elastic plate 25, is smaller than the outer diameter of the tubing. This allows the sealing recess 26 to more tightly clamp the tubing during use, thereby improving the sealing performance.

[0049] In some embodiments, a connecting groove 242 is provided on the outer periphery of both the semi-annular elastic plate 24 and the semi-annular elastic plate 25.

[0050] During vulcanization, the sealing rubber 21 flows into the connecting groove 242 to achieve a tight connection between the semi-annular elastic plate 24, the semi-annular elastic plate 25, and the sealing rubber 21, preventing them from easily falling off. The connecting groove 242 can also alter the mechanical properties of the semi-annular elastic plate 24 and the semi-annular elastic plate 25, reducing their stiffness and allowing for precise control of deformation under ultra-high sealing pressure. This ensures the sealing effect while preventing damage to the sealed tubular structure from compression.

[0051] Specifically, there are multiple connecting grooves 242, which are spaced apart and evenly arranged circumferentially along the semi-annular elastic plate 24 or the semi-annular elastic plate 25. Each connecting groove 242 is a cylindrical open groove; the long axis of the connecting groove 242 is aligned with the expansion direction of the semi-annular elastic plate 24 or the semi-annular elastic plate 25 when compressed. A portion of the sealing rubber 21 is embedded in the multiple connecting grooves 242 to achieve a tight fit between the semi-annular elastic plate 24, the semi-annular elastic plate 25, and the sealing rubber 21, preventing detachment during use. The semi-annular elastic plate 24 and the semi-annular elastic plate 25 have the same structure.

[0052] In some embodiments, the circumferential profile curvature of the inner wall surfaces of the semi-annular elastic plate 24 and the semi-annular elastic plate 25 can be designed to be slightly smaller than the profile curvature of the outer wall surface of the corresponding tube column. When in contact sealing, the semi-annular elastic plate 24 and the semi-annular elastic plate 25 are in an expanded state so that they can effectively fill the tiny gaps between themselves and the outer wall of the tube column by means of elastic deformation, preventing the sealing rubber 21 from being squeezed out of the gap due to increased fluidity under high temperature, thereby ensuring the integrity of the seal.

[0053] In some embodiments, the left and right ends of the front sealing mounting groove 12 correspond one-to-one with the left and right ends of the top sealing mounting groove 13 and are connected through the overlapping channel 14 provided inside the gate body 1; the top seal 3 and the sealing rubber 21 are connected at the connection between the front sealing mounting groove 12 and the top sealing mounting groove 13 to form a sealing strip structure.

[0054] The top seal 3 can be made of rubber. The sealing rubber 21, as the main component of the front seal, is connected to the top seal 3 through the overlapping channel 14. The overlapping channel 14 is cleverly placed inside the gate body, which can effectively guide the flow path of the sealing fluid, reduce the loss of rubber during the flow process, and improve the pressure distribution uniformity of the sealing fluid. When the gate is pressure-bearing, the amount of rubber at the overlapping position of the top seal and the front seal can be increased to enhance the stability and reliability of the seal and further improve the overall sealing performance.

[0055] In some embodiments, both ends of the first strip pad 22 and the second strip pad 23 are bent and embedded in the sealing rubber 21 to form a flow rubber limiting part.

[0056] The two ends of the strip pad 22 and the two strip pads 23 are bent and embedded in the sealing rubber 21 along their length. This effectively restricts the flow of the rubber along the left and right directions of the gate body 1. Together with the semi-annular elastic plate 24 and the semi-annular elastic plate 25, they can effectively fill and prevent extrusion of gaps in all directions, thus ensuring the stability of the sealing rubber 21 under ultra-high pressure and high temperature conditions. This comprehensively controls the problem of rubber being squeezed out of gaps and broken due to increased fluidity and weakened strength under high temperature, thereby preventing sealing failure.

[0057] Specifically, the left and right ends of strip pad 1 22 and strip pad 23 are respectively arranged close to the left and right edges of the gate body 1, so that the left and right ends of strip pad 1 22 and strip pad 23 can be close to the inner wall of the gate cavity (the gate body 1 is slidably connected in the gate cavity of the blowout preventer and can move under the guidance of the gate cavity), effectively constraining the gap in this direction (i.e. the gap between the sealing rubber 21 and the inner wall of the gate cavity) and preventing the flowing rubber from being squeezed out at this gap.

[0058] Specifically, both strip pad 1 22 and strip pad 23 are metal plates or alloy plates.

[0059] In some embodiments, the sealing rubber 21 is vulcanized and tightly bonded together with the strip pad 22, the strip pad 23, the semi-annular elastic plate 24, and the semi-annular elastic plate 25 during vulcanization.

[0060] The sealing rubber 21 is tightly bonded to the strip pad 22, the strip pad 23, the semi-annular elastic plate 24, and the semi-annular elastic plate 25 through vulcanization, which can prevent it from falling off and improve the sealing stability and durability.

[0061] In some embodiments, the semi-annular elastic plate 24 and the semi-annular elastic plate 25 are both metal plates or alloy plates with a hardness lower than that of the column to be sealed, and both have a certain elastic deformation capacity.

[0062] By precisely controlling the material composition and optimizing the processing technology, the strength of the semi-annular elastic plate 24 and the semi-annular elastic plate 25 can be effectively reduced, making their hardness lower than that of the tube to be sealed, making them easier to deform, and preventing damage to the tube to be sealed due to excessive compression when sealing under ultra-high pressure.

[0063] Specifically, the blowout preventer's gate assembly includes two tubing string gate sealing assemblies, symmetrically distributed within the blowout preventer's gate cavity on both sides of the borehole. When it is necessary to seal the ultra-high pressure, high-temperature fluid within the well, the shut-off procedure is initiated. During this process, under the powerful thrust of the hydraulic cylinders on both sides of the blowout preventer, the gate body 1 moves rapidly and smoothly from both sides of the gate cavity along the pre-set guide structure towards the center of the borehole, ultimately clamping the required sealing tubing string inside the borehole. Through the tight fit between the mounting groove on the gate body 1 and the sealing assembly, and the structural characteristics of the sealing assembly itself, a reliable sealing strip is formed, achieving efficient sealing of the tubing string, effectively preventing fluid leakage within the well, and ensuring operational safety.

[0064] The overlap channel 14 between the top seal 3 and the sealing rubber 21 of the sealing gasket structure 2 is formed through an innovative optimization design of the geometry of the gate body 1 and the top seal 3. This increases the amount of rubber at the front end of the top seal 3 while concealing the overlap channel 14 inside the gate body. This unique structural design can precisely guide the flow path of the sealing fluid. By optimizing the shape, size, and direction of the flow channel, it effectively reduces rubber loss during the flow process and improves the uniformity of pressure distribution of the sealing fluid, thereby significantly enhancing the stability and reliability of the seal. At the same time, the overlap channel can also compensate for wear and deformation of the sealing assembly during long-term use to a certain extent, further improving the overall sealing performance and enabling it to operate stably for a long time under harsh conditions of ultra-high pressure and high temperature.

[0065] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0066] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A gate valve sealing assembly for a blowout preventer, wherein the front end face of the gate valve body (1) has a recess (11) for accommodating the tube string and is provided with a front sealing mounting groove (12) extending to the left and right sides, and the top end face is provided with a top sealing mounting groove (13) extending to the left and right sides; characterized in that, include: A sealing pad structure (2) is installed in the front sealing mounting groove (12); the sealing pad structure (2) includes a sealing rubber (21), a strip-shaped pad one (22) embedded at the top of the sealing rubber (21), a strip-shaped pad two (23) embedded at the bottom of the sealing rubber (21), a semi-annular elastic plate one (24) parallel to the lower end face of the strip-shaped pad one (22) and embedded in the sealing rubber (21), and a semi-annular elastic plate two (25) parallel to the upper end face of the strip-shaped pad two (23) and embedded in the sealing rubber (21); The sealing rubber (21) has a concave surface 1 (211) formed in the middle of its front end; the front ends of the strip pad 1 (22) and the strip pad 2 (23) are arranged corresponding to the front end face of the sealing rubber (21) and a concave surface 2 (221) is formed at the position corresponding to the concave surface 1 (211); the inner peripheral wall surface (241) of the semi-annular elastic plate 1 (24) and the semi-annular elastic plate 2 (25) are all corresponding to the concave surface 1 (211); the concave surface 1 (211), the concave surface 2 (221) and the inner peripheral wall surface (241) have the same outline and together constitute a sealing concave surface (26) for pressing against the outer peripheral wall of the sealing tube column; Top seal (3) is installed in the top seal mounting groove (13).

2. The blowout preventer tubular gate sealing assembly according to claim 1, characterized in that, The front ends of the sealing rubber (21), the first strip pad (22), the second strip pad (23), the first semi-annular elastic plate (24), and the second semi-annular elastic plate (25) can all extend out of the front sealing mounting groove (12) and enter the recess (11); there is a preset distance between the rear end face of the first strip pad (22) and the second strip pad (23) and the rear end face of the sealing rubber (21).

3. The blowout preventer string gate sealing assembly according to claim 1, characterized in that, Both the first semi-annular elastic plate (24) and the second semi-annular elastic plate (25) have connecting grooves (242) on their outer periphery.

4. The blowout preventer string gate sealing assembly according to claim 1, characterized in that, The left and right ends of the front sealing mounting groove (12) correspond one-to-one with the left and right ends of the top sealing mounting groove (13) through the overlapping channel (14) set inside the gate body (1); the top sealing element (3) and the sealing rubber (21) are connected at the connection between the front sealing mounting groove (12) and the top sealing mounting groove (13) to form a sealing strip structure.

5. The blowout preventer tubular gate sealing assembly according to claim 1, characterized in that, Both ends of the first strip pad (22) and the second strip pad (23) are bent and embedded into the sealing rubber (21) to form a flow rubber limiting part.

6. The blowout preventer string gate sealing assembly according to claim 5, characterized in that, The sealing rubber (21) is vulcanized and tightly bonded together with the strip pad one (22), the strip pad two (23), the semi-annular elastic plate one (24) and the semi-annular elastic plate two (25) during the vulcanization process.

7. The blowout preventer string gate sealing assembly according to claim 6, characterized in that, Both the first semi-annular elastic plate (24) and the second semi-annular elastic plate (25) are metal plates with a hardness lower than that of the column to be sealed.

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