A multi-time open-close blowout preventer valve

Abstract

The application provides a multiple-time normally-opened and normally-closed blowout prevention valve, which comprises a shell, a valve seat, a valve core assembly and a positioning cylinder, the valve core assembly comprises a valve core body and a lower valve core rod, the valve core body is provided with a sealing surface matched with the valve seat, the lower valve core rod is externally sleeved with a sliding cylinder, the lower valve core rod is movably connected with the sliding cylinder through sealing plugs at the upper and lower ends of the lower valve core rod, the sliding cylinder is sleeved in the positioning cylinder through a threaded sleeve, a first compression spring is arranged between the positioning cylinder and the valve core body, the lower valve core rod is provided with a guide sliding groove, the sliding cylinder is provided with a guide push rod which is slidably matched in the guide sliding groove, the guide sliding groove comprises a normally-closed station and a blowout prevention station in sequence, and the normally-closed station and the blowout prevention station are connected in a head-to-tail mode to form a spiral ring-shaped guide sliding groove. The multiple-time normally-opened and normally-closed behavior of the valve is realized through the cooperation of the shape, track and movement of the guide sliding groove and the guide push rod; meanwhile, the valve core is centered and constrained at multiple positions, so that the centering degree and the running stability of the valve core on the valve seat are improved.

Description

Technical Field

[0001] This invention relates to the field of valve technology, and more specifically, to a normally open and normally closed anti-blowout valve. Background Technology

[0002] Internal blowout preventers (BOPs) are crucial tools in oil and gas drilling. Their function is to prevent fluid from flowing back up through the drill pipe in dangerous situations such as overflows, kicks, and blowouts, thus preventing the escalation of the accident and making handling more difficult. Existing internal BOPs are mainly classified into normally closed and normally open types.

[0003] Existing blowout preventers generally cannot achieve multiple normally open and normally closed cycles, and under high-pressure operating conditions, due to poor alignment and other reasons, there are problems such as incomplete valve core sealing and unstable operation when closing.

[0004] Therefore, designing a drill bit internal blowout preventer that can be opened and closed multiple times, has good centering, and has a tight valve core seal is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide a multiple normally open and normally closed anti-blowout valve, which achieves multiple normally open and normally closed behavior of the valve through the design of the guide groove shape, trajectory and the movement coordination of the guide push rod; at the same time, the valve core is aligned and constrained in multiple places, which improves the alignment of the valve core on the valve seat and the smoothness of operation, and ensures the sealing effect of the valve core when the valve is closed.

[0006] The embodiments of the present invention are implemented as follows:

[0007] This invention provides a multiple normally open and normally closed blowout preventer valve, comprising a housing, a valve seat disposed in the upper part of the housing, a valve core assembly that slides axially with the valve seat, and a positioning cylinder disposed in the lower part of the housing. The valve core assembly includes a valve core body and a lower valve core rod disposed below the valve core body. The valve core body is provided with a sealing surface adapted to the valve seat. A slide cylinder is slidably sleeved on the lower valve core rod. The upper and lower ends of the lower valve core rod are movably connected to the slide cylinder through sealing plugs. The slide cylinder is threaded into the positioning cylinder. A first compression spring is provided between the positioning cylinder and the valve core body. A guide groove is provided on the lower valve core rod. A guide push rod that slides within the guide groove is provided inside the slide cylinder. The guide groove sequentially includes a normally closed position and a blowout preventer position. The normally closed position and the blowout preventer position are connected end to end to form a spiral annular guide groove.

[0008] Furthermore, the lower valve core rod has a guide post in the middle, and the guide groove is set on the guide post. The diameter of the guide post is larger than the diameter of the upper end of the lower valve core rod. The guide post is located inside the slide cylinder. Bearings are provided between the upper and lower ends of the guide post and the slide cylinder. The outer wall of the bearing is fixedly connected to the inner wall of the slide cylinder, and the inner side of the bearing is clearance-fitted with the guide post.

[0009] Furthermore, the normally closed station is located at the highest point of the guide chute, and a normally open station is also provided below the normally closed station. The anti-spray station is located at the lowest point of the guide chute.

[0010] Furthermore, the normally closed station has a first chute from one side to the blowout preventer station. The first chute is a spiral downward chute, and its depth gradually decreases from top to bottom. The blowout preventer station has a second chute from the other side to the normally closed station. The second chute is a spiral upward chute, and its depth gradually decreases from bottom to top. The normally closed station is provided with a first anti-reverse protrusion near the end of the second chute, and the blowout preventer station is provided with a second anti-reverse protrusion near the end of the first chute.

[0011] Furthermore, an upper valve core rod is provided above the valve core body, and a centering hole is provided in the middle of the valve seat. The upper valve core rod moves through the centering hole, and a flow groove is also provided around the centering hole of the valve seat.

[0012] Furthermore, the valve seat is fixedly connected to the outer shell by threads, and O-rings are provided between the upper and lower ends of the valve seat and the outer shell.

[0013] Furthermore, spring grooves are provided on the lower surface of the valve core and the upper surface of the positioning cylinder, and the upper and lower ends of the first compression spring are respectively placed in the spring grooves on the lower surface of the valve core and the upper surface of the positioning cylinder.

[0014] Furthermore, the side wall of the slide cylinder is provided with an assembly square groove and a limiting groove that are interconnected. The assembly square groove is connected to the outside of the slide cylinder, and the limiting groove is connected to the inside of the slide cylinder. The guide push rod includes a limiting part and a guiding part. The limiting part is located in the assembly square groove. A threaded plug is provided at the end of the assembly square groove near the outside of the slide cylinder. A second compression spring is provided between the threaded plug and the limiting part.

[0015] Furthermore, the positioning cylinder has multiple guide holes and multiple flow holes on its side wall, and the guide holes and flow holes are connected to the bottom of the positioning cylinder.

[0016] Furthermore, a positioning boss is provided at the bottom of the outer shell, and the bottom of the positioning cylinder is mounted on the positioning boss.

[0017] The beneficial effects of the multi-operation normally open and normally closed blowout preventer valve provided by this invention include:

[0018] 1. The guide chute of the present invention includes a normally closed station and a blowout prevention station. The normally closed station and the blowout prevention station are connected end to end to form a spiral ring structure. Its shape, trajectory and the motion coordination design of the guide push rod realize the multiple normally open and normally closed behaviors of the valve.

[0019] 2. Multiple sealing plugs at the upper and lower ends of the valve core rod and the centering hole are used to constrain the valve core at multiple points, which improves the centering accuracy of the valve core assembly on the valve seat and the smoothness of operation, and ensures the sealing effect of the valve core when the valve is closed.

[0020] 3. The direct threaded connection between the slide cylinder and the positioning cylinder allows the slide cylinder to be stably installed into the housing through the positioning cylinder, ensuring the installation effect of the slide cylinder. At the same time, the slide cylinder can also be removed from the positioning cylinder from the bottom of the housing to replace the parts inside the slide cylinder, making the operation more convenient. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a cross-sectional structural diagram of the normally open and normally closed anti-blowout valve of the present invention.

[0023] Figure 2 This is a schematic diagram of the valve core structure in this invention;

[0024] Figure 3 This is a schematic diagram of the valve core from another angle in this invention;

[0025] Figure 4 This is a schematic diagram of the valve seat structure in this invention;

[0026] Figure 5 This is a schematic diagram of the structure of the positioning cylinder and the sliding cylinder in this invention;

[0027] Figure 6 This is a schematic cross-sectional view of the sliding cylinder in this invention;

[0028] Figure 7 This is a schematic cross-sectional view of the connection between the positioning cylinder and the sliding cylinder in this invention.

[0029] Figure 8 This is a schematic diagram of the guide push rod in this invention;

[0030] Icons: 1. Outer shell; 2. Valve seat; 21. Centering hole; 22. Flow groove; 3. Valve core body; 4. Positioning cylinder; 41. Guide hole; 42. Flow hole; 5. Upper valve core rod; 6. Lower valve core rod; 61. Guide column; 62. Bearing; 7. Sealing surface; 8. Slide cylinder; 81. Assembly square groove; 82. Limiting groove; 83. Threaded plug; 9. Sealing plug; 10. First compression spring; 11. Guide slide groove; 111. Normally open position; 112. Normally closed position; 113. Anti-blowout position; 114. First slide groove; 115. Second slide groove; 116. First anti-reverse protrusion; 117. Second anti-reverse protrusion; 12. Guide push rod; 121. Limiting part; 122. Guide part; 123. Second compression spring. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0032] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0033] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0034] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0035] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0036] Example 1: As Figure 1-8 As shown, the present invention provides a multiple normally open and normally closed anti-blowout valve, including a housing 1, a valve seat 2 disposed in the upper part of the housing 1, a valve core assembly that slides axially with the valve seat 2, and a positioning cylinder 4 disposed in the lower part of the housing 1. The valve core assembly includes a valve core body 3 and a lower valve core rod 6 disposed below the valve core body 3. The valve core body 3 is provided with a sealing surface 7 adapted to the valve seat 2. A sliding cylinder 8 is slidably sleeved on the lower valve core rod 6. The upper and lower ends of the lower valve core rod 6 are connected to the valve seat 2 by sealing plugs 9. The slide cylinder 8 is movably connected and is threadedly fitted inside the positioning cylinder 4. A first compression spring 10 is provided between the positioning cylinder 4 and the valve core body 3. A guide groove 11 is provided on the lower valve core. A guide push rod 12 is provided inside the slide cylinder 8 and slides within the guide groove 11. The guide groove 11 includes a normally closed position 112 and a blowout preventer position 113 in sequence. The normally closed position 112 and the blowout preventer position 113 are connected end to end to form a spiral annular guide groove 11.

[0037] The guide chute 11 of this invention includes a normally closed station 112 and a blowout preventer station 113. The normally closed station 112 and the blowout preventer station 113 are connected end to end to form a spiral ring structure. Its shape, trajectory, and the motion coordination design of the guide push rod 12 realize multiple normally open and normally closed behaviors of the valve. The centering hole 21 and multiple sealing plugs 9 at the upper and lower ends of the lower valve core rod 6 are used to constrain the valve core at multiple points, which improves the centering accuracy and operational stability of the valve core assembly on the valve seat 2 and ensures the sealing effect of the valve core when the valve is closed. The direct threaded connection design between the slide cylinder 8 and the positioning cylinder allows the slide cylinder 8 to be stably installed into the outer shell 1 through the positioning cylinder, ensuring the installation effect of the slide cylinder 8. At the same time, the slide cylinder 8 can be removed from the positioning cylinder from the bottom of the outer shell 1 to replace the parts inside the slide cylinder 8, making the operation more convenient. The positioning cylinder 4 has multiple flow guide holes 41 and multiple flow passage holes 42 on its side wall. The flow guide holes 41 and flow passage holes 42 are connected to the bottom of the positioning cylinder 4 to facilitate the flow of mud.

[0038] The normally closed station 112 is located at the highest point of the guide groove 11, and a normally open station 111 is also provided below the normally closed station 112. The anti-blowout station 113 is located at the lowest point of the guide groove 11. Under the action of the first compression spring 10, the valve core 3 moves closer to the valve seat 2. When there is no other external force, the valve core 3 and the valve seat 2 are in contact, sealing the entire channel.

[0039] The guide push rod 12 moves in the guide groove 11 to complete the valve state change.

[0040] (1) When no mud is injected, the guide push rod 12 is in the initial state when it is in the normally open position 111. The valve core 3 is stuck in the normally open position 111 by the upward force of the first compression spring 10. At this time, the valve is a normally open valve and the valve is open.

[0041] (2) When the slurry is injected at a higher pressure, the valve core 3 is subjected to the downward force of the slurry, and the guide push rod 12 is in the normally closed position 112, which is removed from the initial state. At this time, the valve is a normally closed valve and the valve is open.

[0042] (3) When the well blows out, the pressure inside the valve is balanced. The spring force of the first compression spring 10 is greater, which pushes the valve core 3 upward to squeeze the guide push rod 12. The valve closes quickly, and the push rod is in the blowout prevention position 113. The valve is closed.

[0043] (5) When the pressure is increased again, the guide push rod 12 returns to the normally closed position 112 along the spiral guide groove 11.

[0044] The valve as a whole performs the following actions: normally open position 111, normally closed position 112, blowout preventer position 113, normally closed position 112, blowout preventer position 113…

[0045] Example 2: Figure 2-3 As shown, based on Embodiment 1, the lower valve core rod 6 has a guide post 61 in the middle, and the guide groove 11 is set on the guide post 61. The diameter of the guide post 61 is larger than the diameter of the upper end of the lower valve core rod 6. The guide post 61 is located inside the slide cylinder 8. Bearings 62 are provided between the upper and lower ends of the guide post 61 and the slide cylinder 8. The outer wall of the bearing 62 is fixedly connected to the inner wall of the slide cylinder 8, and the inner side of the bearing 62 is clearance-fitted with the guide post 61.

[0046] The increased diameter of the guide post 61 allows for a larger guide groove 11, which is compatible with a larger guide push rod 12, improving guiding stability. The bearings 62 at both ends of the guide post 61 facilitate valve state transitions, preventing damage to valve components caused by jamming / slowness between the guide post 61 and the slide 8 during transitions, and preventing accelerated erosion of the valve core sealing surface 7 due to prolonged exposure to a small flow area. The bearings 62 ensure smoother sliding of the guide post 61 within the slide 8. Furthermore, the bearings 62 at both ends of the guide post 61 provide a centering effect when the guide post 61 deviates within the slide 8, preventing significant sliding of the guide post 61 and thus preventing lateral wobbling of the valve core 3. This ensures smooth separation and sealing between the valve core 3 and the valve seat 2. The clearance fit between the inner side of the bearing 62 and the guide post 61 does not impede the rotation of the guide post 61 within the slide 8.

[0047] A positioning boss is provided at the bottom of the inner shell 1, and the bottom of the positioning cylinder 4 is mounted on the positioning boss. The lower end of the positioning cylinder 4 is constrained by the positioning boss inside the outer shell 1, and the upper end of the positioning cylinder 4 is constrained by the first compression spring 10, which fits perfectly inside the outer shell 1.

[0048] Example 3: Figure 1-3As shown, based on Embodiment 1, the normally closed station 112 has a first chute 114 extending from one side to the blowout preventer station 113. The first chute 114 is a spiral downward chute, and its depth gradually decreases from top to bottom. The blowout preventer station 113 has a second chute 115 extending from the other side to the normally closed station 112. The second chute 115 is a spiral upward chute, and its depth gradually decreases from bottom to top. The normally closed station 112 is provided with a first anti-reverse protrusion 116 near the end of the second chute 115, and the blowout preventer station 113 is provided with a second anti-reverse protrusion 117 near the end of the first chute 114.

[0049] The groove depths of the first groove 114 and the second groove 115 are both gradually changed. At the same time, the first anti-reverse protrusion 116 and the second anti-reverse protrusion 117 are also provided, so that the guide push rod 12 can only perform unidirectional cyclic action in the guide groove 11 according to the setting, thus avoiding malfunction.

[0050] Example 4: Figure 4 As shown in Embodiment 1, an upper valve core rod 5 is provided above the valve core body 3, and a centering hole 21 is provided in the middle of the valve seat 2. The upper valve core rod 5 moves through the centering hole 21, and a flow groove 22 is also provided around the centering hole 21 of the valve seat 2. The valve seat 2 is fixedly connected to the outer shell 1 by threads, and O-rings are provided between the upper and lower ends of the valve seat 2 and the outer shell 1.

[0051] The upper valve core rod 5 is located inside the centering hole 21, ensuring the centering and stability of the upper part of the valve core body 3. At the same time, the lower valve core rod 6 at the bottom of the valve core body 3 is sleeved inside the slide cylinder 8. The lower valve core rod 6 can only rotate and slide up and down inside the slide cylinder 8, ensuring the centering and stability of the lower part of the valve core body 3. The constraint of multiple centerings allows the entire valve core assembly to rotate and move smoothly within the valve seat 2.

[0052] Example 5: Figure 5-8 As shown, based on Embodiment 1, spring grooves are provided on the lower surface of the valve core 3 and the upper surface of the positioning cylinder 4. The upper and lower ends of the first compression spring 10 are respectively placed in the spring grooves on the lower surface of the valve core 3 and the upper surface of the positioning cylinder 4. The design of the spring grooves makes the spring more stable in fixing between the valve core 3 and the positioning cylinder, avoiding spring wobbling.

[0053] The slide cylinder 8 is installed into the outer casing 1 via the positioning cylinder 4, facilitating its installation. Simultaneously, the sealing plug 9 seals the upper and lower ends of the guide post 61 within the slide cylinder 8, isolating it from the external mud and sand environment. This ensures smooth rotation of the guide post 61 within the slide cylinder 8 and prevents mud and sand from entering the guide groove 11 and obstructing the guide push rod 12. Furthermore, the positioning cylinder 4 and the slide cylinder 8 are integrated, allowing the first compression spring 10 to be positioned on the outer side of the positioning cylinder 4. This enlarges the diameter of the first compression spring 10, allowing it to be located further outwards from the valve core 3, providing more stable support and preventing displacement of the valve core 3.

[0054] Meanwhile, the lower part of the positioning cylinder 4 is open, and the middle part of the slide cylinder 8 is connected to the positioning cylinder 4 by threads, so that the slide cylinder can be disassembled from the lower part of the positioning cylinder 4, which facilitates the replacement of internal components of the slide cylinder 8 without completely disassembling the valve.

[0055] The slide cylinder 8 has an assembly square groove 81 and a limiting groove 82 that are interconnected on its side wall. The assembly square groove 81 is connected to the outside of the slide cylinder 8, and the limiting groove 82 is connected to the inside of the slide cylinder 8. The guide push rod 12 includes a limiting part 121 and a guide part 122. The limiting part 121 is located inside the assembly square groove 81. A threaded plug 83 is provided at the end of the assembly square groove 81 near the outside of the slide cylinder 8. A second compression spring 123 is provided between the threaded plug 83 and the limiting part 121.

[0056] The guide push rod 12 is installed in the assembly square groove 81 and the limiting groove 82 of the slide cylinder 8. One end of the slide cylinder 8 is sealed by a threaded plug 83. The second compression spring 123 is located between the threaded plug 83 and the limiting part 121. Since the depth of the guide groove 11 is different at different points, the guide push rod 12 needs to move along its axial direction. The second compression spring 123 ensures that the guide part 122 is always tangent to the bottom of the guide groove 11 when it moves. The limiting part 121 is located in the limiting square groove, which avoids the rotation of the guide push rod 12 and facilitates positioning.

[0057] This invention achieves multiple normally open and normally closed behaviors of the valve through the design of the shape and trajectory of the guide groove 11 and the motion coordination of the guide push rod 12; at the same time, it performs centering and constraint on the valve core in multiple places, which improves the centering degree of the valve core on the valve seat 2 and the smoothness of operation, and ensures the sealing effect of the valve core when the valve is closed.

[0058] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A normally open and normally closed anti-blowout valve, characterized in that: The system includes a housing (1), a valve seat (2) located in the upper part of the housing (1), a valve core assembly that slides axially with the valve seat (2), and a positioning cylinder (4) located in the lower part of the housing (1). The valve core assembly includes a valve core body (3) and a lower valve core rod (6) located below the valve core body (3). The valve core body (3) is provided with a sealing surface (7) adapted to the valve seat (2). A sliding cylinder (8) is slidably sleeved on the lower valve core rod (6). The upper and lower ends of the lower valve core rod (6) are movably connected to the sliding cylinder (8) through sealing plugs (9). The slide cylinder (8) is threaded into the positioning cylinder (4). A first compression spring (10) is provided between the positioning cylinder (4) and the valve core body (3). A guide groove (11) is provided on the lower valve core rod (6). A guide push rod (12) is provided in the slide cylinder (8) and slides in the guide groove (11). The guide groove (11) includes a normally closed position (112) and a blowout prevention position (113) in sequence. The normally closed position (112) and the blowout prevention position (113) are connected end to end to form a spiral annular guide groove (11). The lower valve core rod (6) has a guide post (61) in the middle. The guide groove (11) is set on the guide post (61). The diameter of the guide post (61) is larger than the diameter of the upper end of the lower valve core rod (6). The guide post (61) is located inside the slide cylinder (8). Bearings (62) are provided between the upper and lower ends of the guide post (61) and the slide cylinder (8). The outer wall of the bearing (62) is fixedly connected to the inner wall of the slide cylinder (8). The inner side of the bearing (62) is clearance-fitted with the guide post (61). An upper valve core rod (5) is provided above the valve core body (3), and a centering hole (21) is provided in the middle of the valve seat (2). The upper valve core rod (5) moves through the centering hole (21), and a flow groove (22) is provided around the centering hole (21) of the valve seat (2). The slide cylinder (8) has an assembly square groove (81) and a limiting groove (82) that are interconnected on its side wall. The assembly square groove (81) is connected to the outside of the slide cylinder (8), and the limiting groove (82) is connected to the inside of the slide cylinder (8). The guide push rod (12) includes a limiting part (121) and a guide part (122). The limiting part (121) is located inside the assembly square groove (81). A threaded plug (83) is provided at the end of the assembly square groove (81) near the outside of the slide cylinder (8). A second compression spring (123) is provided between the threaded plug (83) and the limiting part (121).

2. The multiple normally open and normally closed anti-blowout valve according to claim 1, characterized in that: The normally closed station (112) is located at the highest point of the guide chute (11), and a normally open station (111) is also provided below the normally closed station (112). The anti-spray station (113) is located at the lowest point of the guide chute (11).

3. The multiple normally open and normally closed anti-blowout valve according to claim 1, characterized in that: The normally closed station (112) has a first chute (114) from one side to the blowout preventer station (113). The first chute (114) is a spiral downward chute, and the depth of the first chute (114) gradually decreases from top to bottom. The blowout preventer station (113) has a second chute (115) from the other side to the normally closed station (112). The second chute (115) is a spiral upward chute, and the depth of the second chute (115) gradually decreases from bottom to top. The normally closed station (112) is provided with a first anti-reverse protrusion (116) near the end of the second chute (115), and the blowout preventer station (113) is provided with a second anti-reverse protrusion (117) near the end of the first chute (114).

4. The multiple normally open and normally closed anti-blowout valve according to claim 1, characterized in that: The valve seat (2) is fixedly connected to the outer shell (1) by threads, and O-rings are provided between the upper and lower ends of the valve seat (2) and the outer shell (1).

5. The multiple normally open and normally closed anti-blowout valve according to claim 1, characterized in that: The lower surface of the valve core (3) and the upper surface of the positioning cylinder (4) are provided with spring grooves, and the upper and lower ends of the first compression spring (10) are respectively placed in the spring grooves on the lower surface of the valve core (3) and the upper surface of the positioning cylinder (4).

6. The multiple normally open and normally closed anti-blowout valve according to claim 1, characterized in that: The positioning cylinder (4) has multiple guide holes (41) and multiple flow holes (42) on its side wall. The guide holes (41) and flow holes (42) are connected to the bottom of the positioning cylinder (4).

7. The multiple normally open and normally closed anti-blowout valve according to claim 1, characterized in that: The bottom of the outer shell (1) is provided with a positioning boss, and the bottom of the positioning cylinder (4) is mounted on the positioning boss.

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