Blind plate valve combination sealing structure and single-gate valve, double-gate valve and spherical gate valve

Abstract

This invention discloses a blind valve combined sealing structure and single gate valves, double gate valves, and spherical gate valves. The blind valve combined sealing structure includes: a valve body, a valve seat, and a valve plate. The valve plate is placed in the inner cavity of the valve body, and the valve seat is placed in the flow channel of the valve body, with the valve seat and valve plate in sealing contact. A first annular sealing groove is provided on the outer peripheral wall of the valve seat, and the first annular sealing groove is filled with sealing grease for sealing contact with the inner wall of the flow channel of the valve body. A first inlet and outlet pipe is connected to the inner cavity and is used to pressurize the inner cavity to achieve high-pressure gas sealing or for valve sealing performance testing. The first inlet and outlet pipe is provided with a first inlet valve and a first outlet valve. The valve body of this invention adopts multiple seals to improve the sealing reliability of the valve body.

Description

Technical Field

[0001] This invention relates to the field of valve body sealing technology, and more specifically to blind valve combination sealing structures and single gate valves, double gate valves, and spherical gate valves. Background Technology

[0002] In chemical production, blind valves are commonly used in pipelines transporting flammable, explosive, toxic, and hazardous fluids. Existing blind valves generally employ a single sealing structure, which lacks reliability; for example, they typically only have a rubber or PTFE sealing ring on the valve seat. When this seal undergoes permanent deformation due to prolonged pressure, aging due to media corrosion, or wear of the sealing surface due to pipeline stress, leakage will occur. Especially for high-temperature, high-pressure media or media containing solid particles, the single sealing structure is highly prone to failure and cannot provide a reliable seal over long periods. Summary of the Invention

[0003] In view of this, the present invention provides a blind valve combined sealing structure and a single gate valve, a double gate valve, and a spherical gate valve to improve the sealing performance of the valve.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A blind valve combined sealing structure includes: a valve body, a valve seat, and a valve plate, wherein the valve plate is placed in the inner cavity of the valve body, the valve seat is placed in the flow channel of the valve body, and the valve seat and the valve plate are in sealing contact; The outer peripheral wall of the valve seat is provided with a first annular sealing groove, and the first annular sealing groove is filled with sealing grease for sealing contact with the inner wall of the flow channel of the valve body. The first intake and exhaust pipe is connected to the inner cavity and is used to fill the inner cavity with gas to achieve high-pressure gas sealing or for valve sealing testing. The first intake and exhaust pipe is provided with a first intake valve and a first exhaust valve.

[0006] Furthermore, a first annular sealing groove is provided on both sides of the first annular sealing groove on the outer peripheral wall of the valve seat, and a first annular sealing ring is installed in each of the first annular sealing grooves to prevent leakage of the sealant.

[0007] Furthermore, the valve seat has an elastic sealing element and a rigid sealing pressure plate on the side surface that is in sealing contact with the valve plate.

[0008] Furthermore, the valve body is equipped with a pressure detector for monitoring the pressure in the inner cavity, and the bottom end of the valve body is equipped with a drain pipe communicating with the inner cavity. The drain pipe is equipped with a drain valve and a flow monitor for monitoring the fluid flow rate.

[0009] This invention provides a single gate valve, comprising: The combined sealing structure includes a single gate valve plate and a valve seat comprising: a first positioning ring and two sliding sealing sleeves respectively embedded in the inlet and outlet sides of the flow channel. The two first positioning rings are spaced apart, and the two sliding sealing sleeves are located in the inner cavity and respectively fitted on the two first positioning rings. The valve plate can be placed between the two sliding sealing sleeves. Each of the two sliding sealing sleeves is provided with an elastic sealing element and a rigid sealing pressure plate on the side facing the valve plate. The elastic sealing element is fitted on the sliding sealing sleeve, and the rigid sealing pressure plate is fitted on the outside of the elastic sealing element. A sliding sealing sleeve drive is provided on the valve body to drive the two sliding sealing sleeves to move, thereby making the elastic sealing elements and rigid sealing pressure plates on the two sliding sealing sleeves make sealing contact with the two sides of the single gate. A single gate drive cylinder is mounted on the valve body. The telescopic end of the single gate drive cylinder is fixed to the first valve stem on the single gate plate, and is used to drive the single gate plate to rise and fall, so that the single gate plate moves in and out between the two first positioning rings. The first positioning ring has a first annular sealing groove and a second annular sealing groove that are interconnected on its outer peripheral wall. The first positioning ring has a grease injection hole that is connected to the first annular sealing groove and the second annular sealing groove. The inner sleeve wall of the sliding sealing sleeve has a second annular sealing groove on both sides of the second annular sealing groove. A second annular sealing ring is installed in each of the second annular sealing grooves to prevent the grease from leaking.

[0010] Furthermore, there are two sliding sealing sleeve drive components arranged vertically, and each of the two sliding sealing sleeve drive components includes: Two first sliding sleeves are arranged at intervals, and the two first sliding sleeves are respectively slidably installed in two sliding holes of the valve body. One end of each of the two first sliding sleeves is fixedly connected to one of the sliding sealing sleeves. Two first sliding rods are arranged at intervals, and the two first sliding rods are respectively inserted into the two first sliding sleeves. One end of each of the two first sliding rods is fixedly connected to the other sliding sealing sleeve. The first inner connecting plate is located on the outside of the valve body and is fixedly connected to the other ends of the two first sliding sleeves. The first outer connecting plate is located outside the first inner connecting plate, and the first outer connecting plate is fixedly connected to the other ends of the two first sliding rods. The first telescopic cylinder has its cylinder barrel fixed to the first outer connecting plate, and its first telescopic rod passes through the first outer connecting plate and is fixedly connected to the first inner connecting plate.

[0011] Furthermore, the sliding sealing sleeve has a first sealing surface annular groove for filling with sealing grease on the side facing the valve plate. The sliding sealing sleeve has a first flow channel inside. One end of the first flow channel is connected to the first sealing annular groove, and the other end of the first flow channel is connected to and communicates with one end of the grease injection follower tube. The other end of the grease injection follower tube extends out of the valve body.

[0012] Furthermore, each of the sliding sealing sleeve drive components includes two first bellows, which are respectively sleeved on the outer side of the two sliding sealing sleeves. One end of the first bellows is fixedly connected to the inner wall of the inner cavity, and the other end is fixed to the outer wall of the sliding sealing sleeve. It also includes two second inlet and outlet pipes disposed on the valve body. The two second inlet and outlet pipes are respectively connected to the two first bellows through air pipes. The second inlet and outlet pipes are provided with a second inlet valve and a second outlet valve.

[0013] Furthermore, the upper and lower parts of the valve plate are respectively a blind plate sealing surface and a flow hole sealing surface. When the valve plate descends, the flow hole sealing surface on it is located in the receiving box at the lower part of the valve body, and the blind plate sealing surface cuts off the flow channel, and the elastic seal and the rigid sealing plate are in sealing contact with the blind plate sealing surface; when the valve plate rises, the flow hole sealing surface on it communicates with the flow channel, and the elastic seal and the rigid sealing plate are in sealing contact with the flow hole sealing surface to prevent corrosive fluid from entering the inner cavity.

[0014] Furthermore, each of the sliding sealing sleeve drive components includes two first airbags, which are respectively fitted onto the outer sides of the two sliding sealing sleeves. Each first airbag is disposed between the outer protrusion plate on the sliding sealing sleeve and the inner wall of the inner cavity. Each first airbag is connected to a third inlet and outlet pipe disposed on the valve body via an air pipe. The third inlet and outlet pipe is provided with a third inlet valve and a third outlet valve.

[0015] Furthermore, the first airbag has at least a dual-airbag structure, one as a working airbag and the other as a backup airbag.

[0016] This invention provides a dual gate valve, comprising: The blind valve combination sealing structure is described above. The valve plate is a double gate with an inlet side gate and an outlet side gate. The valve seat includes: a second positioning ring respectively embedded in the inlet and outlet sides of the flow channel, the two second positioning rings are arranged at intervals, the outer peripheral wall of the second positioning ring is provided with a first annular sealing groove, the elastic sealing element is sleeved on the second positioning ring, and the rigid sealing pressure plate is sleeved on the outside of the elastic sealing element. A double gate lifting drive cylinder is provided on the valve body. The telescopic end of the double gate lifting drive cylinder is fixed to the second valve stem on the double gate plate, and is used to drive the double gate plate to lift and move the double gate plate between the two second positioning rings. A dual-gate transverse movement drive is provided on the valve body to drive the inlet-side gate and the outlet-side gate away from each other, thereby making the inlet-side gate and the outlet-side gate respectively in sealing contact with the elastic seals on the two second positioning rings and the rigid sealing pressure plate; The lower part of the second valve stem is slidably connected to the T-slots on the inlet-side gate and the outlet-side gate via a T-shaped head.

[0017] Furthermore, wedges are fixed on the adjacent sidewalls of both the inlet-side gate and the outlet-side gate, with the inclined surfaces of the two wedges arranged opposite each other. The dual-gate lateral movement drive includes: The first wedge-shaped push rod passes through the second valve stem, and the lower end of the first wedge-shaped push rod is the first push wedge head. The two inclined surfaces of the first push wedge head abut against the inclined surfaces of the two wedge blocks, which are used to drive the inlet side gate and the outlet side gate to move away from each other. A push rod drive cylinder is fixed on the telescopic end of the double-gate lifting drive cylinder, and the telescopic end of the push rod drive cylinder is fixedly connected to the upper end of the first wedge-shaped push rod.

[0018] Furthermore, a second airbag is fixed on the side wall of the inlet-side gate and the outlet-side gate that are close to each other. The second airbag is U-shaped. The dual-gate lateral movement drive includes: An elliptical head push rod is inserted into the second valve stem, and the lower end of the elliptical head push rod is an elliptical head, which is placed in the U-shaped opening of the second airbag. A push rod drive is used to drive the elliptical head push rod to rotate, so that the long axis of the elliptical head pushes the inlet side gate and the outlet side gate to move away from each other. The elliptical head push rod has a first air supply channel inside. A fourth air intake and exhaust pipe is installed at the upper end of the first air supply channel. A fourth air intake valve and a fourth air exhaust valve are provided on the fourth air intake and exhaust pipe. The lower end of the first air supply channel is connected to the second airbag through an air pipe.

[0019] Furthermore, the second airbag has at least a dual-airbag structure, with one serving as the working airbag and the other as the backup airbag.

[0020] Furthermore, it also includes a fluid delivery pipeline, one end of which is connected to the delivery pipeline on the valve body, and the other end is connected to the fourth inlet and outlet pipeline. A fluid switching valve is provided on the fluid delivery pipeline.

[0021] Furthermore, a third airbag is fixed on the side wall of the inlet side gate and the outlet side gate that are close to each other, and both opposite sides of the inlet side gate and the outlet side gate have protruding beams, and one side of each of the two opposite protruding beams is provided with a wedge-shaped surface. The dual-gate lateral movement drive includes: Two airbag linkage mechanisms are respectively installed on two opposite side walls of the valve body. Each airbag linkage mechanism includes: A protective housing, which is fixed to one side wall of the valve body; U-shaped plate seat, the U-shaped plate seat is disposed inside the protective housing and fixed on one side wall of the valve body; The airbag is pushed, and one side of the airbag is fixed to the inner wall of the U-shaped plate seat; A fixing plate base is disposed inside the protective housing and fixed to one side wall of the valve body; A reset airbag, one side of which is fixed to the fixed plate base; A drive plate is fixed between the push airbag and the reset airbag. A second wedge-shaped push rod is fixed at intervals on the drive plate. The second wedge-shaped push rod passes through the valve body, and the end of the second wedge-shaped push rod is a second push wedge head. The two inclined surfaces of the second push wedge head abut against the two wedge surfaces, which are used to drive the inlet side gate and the outlet side gate to move away from each other. The fifth intake and exhaust pipe passes through the protective shell and is connected to the push airbag through an air pipe. The fifth intake and exhaust pipe is equipped with a fifth intake valve and a fifth exhaust valve. The sixth intake and exhaust pipe passes through the protective shell and is connected to the reset airbag through an air pipe. The sixth intake and exhaust pipe is equipped with a sixth intake valve and a sixth exhaust valve. The second valve stem has a second air supply channel inside. The upper end of the second air supply channel is connected to a seventh air intake and exhaust pipe through an air pipe. The seventh air intake and exhaust pipe is equipped with a seventh air intake valve and a seventh exhaust valve. The lower end of the second air supply channel is connected to the third airbag through an air pipe.

[0022] Furthermore, the fifth, sixth, and seventh intake and exhaust pipes are all connected to the gas supply pipes connected to the valve body via pipe connections.

[0023] Furthermore, the push airbag and / or the reset airbag and / or the third airbag are all at least dual-airbag structures, one as a working airbag and the other as a backup airbag.

[0024] This invention provides a spherical gate valve, comprising: The blind valve combination sealing structure is described above. The valve plate is a spherical gate plate. The valve seat includes: movable sealing rings respectively embedded in the inlet and outlet sides of the flow channel. The two movable sealing rings are arranged at intervals. A movable plate is fixed on the outer peripheral wall of the movable sealing ring. The outer wall of the movable sealing ring is provided with a first annular sealing groove and two first annular sealing ring grooves. A lateral movement drive for the movable sealing rings is provided on the valve body and is used to drive the two movable sealing rings to move laterally, thereby making the inner spherical sealing surfaces of the two movable sealing rings in sealing contact with the outer spherical sealing surfaces of the spherical valve plate. A valve stem drive is provided to drive the third valve stem on the spherical gate to rotate, so that the spherical valve plate opens or opens the flow channel.

[0025] Furthermore, the lateral movement drive of the movable sealing ring includes: Two spaced-apart second sliding sleeves are respectively slidably installed in two sliding holes of the valve body, and one end of each of the two second sliding sleeves is fixedly connected to one of the moving plates. Two spaced-apart second sliding rods are respectively inserted into two second sliding sleeves, and one end of each of the two second sliding rods is fixedly connected to another movable plate. The second inner connecting plate is located on the outside of the valve body, and the second inner connecting plate is fixedly connected to the other end of the two second sliding sleeves. The second outer connecting plate is located outside the second inner connecting plate, and the second outer connecting plate is fixedly connected to the other end of both second sliding rods; The second telescopic cylinder has its cylinder barrel fixed to the second outer connecting plate, and its second telescopic rod passes through the second outer connecting plate and is fixedly connected to the second inner connecting plate.

[0026] Furthermore, a second sealing annular groove for filling with sealant is provided on the inner wall of the inner spherical sealing surface, and the second sealing annular groove communicates with the first annular sealing groove.

[0027] Furthermore, each of the moving sealing ring transverse drive components includes two fourth airbags, which are respectively sleeved on the outer sides of the two moving sealing rings. Each fourth airbag is disposed between the moving plate and the inner wall of the inner cavity. Each fourth airbag is connected to the eighth inlet and outlet pipe disposed on the valve body through an air pipe. The eighth inlet and outlet pipe is provided with an eighth inlet valve and an eighth outlet valve. A fifth airbag is provided between the two movable plates. The fifth airbag is connected to the ninth intake and exhaust pipe provided on the valve body through an air pipe. The ninth intake and exhaust pipe is provided with a ninth intake valve and a ninth exhaust valve.

[0028] Furthermore, the fourth airbag and / or the fifth airbag is at least a dual-airbag structure, with one serving as the working airbag and the other as a backup airbag.

[0029] Furthermore, each of the moving sealing ring transverse drive components includes two second bellows, which are respectively sleeved on the outer side of the two moving sealing rings. One end of the second bellows is fixedly connected to the inner wall of the inner cavity, and the other end is fixed to one side of the moving plate. It also includes two tenth inlet and outlet pipes disposed on the valve body. The two tenth inlet and outlet pipes are respectively connected to the two second bellows through air pipes. The tenth inlet and outlet pipes are provided with a tenth inlet valve and a tenth outlet valve.

[0030] Effects of the invention: I. The four-fold combined sealing works synergistically to achieve absolute zero leakage: This application organically combines four sealing methods—rigid sealing, flexible sealing, grease sealing, and high-pressure gas differential isolation sealing—to construct a multi-layered, complementary sealing system. Rigid seals (metal materials such as titanium alloy and stainless steel): provide high pressure resistance, erosion resistance, and wear resistance as the main sealing capability, and are the core skeleton of the sealing system.

[0031] Flexible seal (elastic materials such as rubber and PTFE): responsible for pre-sealing, can adapt to the parallelism error and micro-unevenness between the gate and the valve seat, and achieve zero leakage in the low pressure stage.

[0032] Grease seals (butter, molybdenum disulfide, etc.): fill the microscopic gaps that cannot be eliminated from the machined metal surface, and at the same time play a dual role of sealing and lubrication, eliminating interface leakage between valve seat and valve body.

[0033] Differential pressure isolation seal (inert gas pressure higher than that of the conveying medium): A high-pressure isolation zone is established in the valve body cavity, and the differential pressure is used to block the leakage of the medium to the outlet side, so as to achieve absolute isolation.

[0034] The four sealing methods complement each other under different pressure stages and media conditions. Even if a certain sealing layer fails locally, the other sealing layers can still maintain the overall sealing performance, ensuring that the valve achieves zero leakage under any operating condition.

[0035] II. Online robust monitoring and maintenance-free operation significantly reduce maintenance costs: This application utilizes the differential pressure sealing characteristics of high-pressure isolation gas to achieve an online tightness test function: after the valve is closed, high-pressure isolation gas is introduced into the inner cavity to build up pressure, and then the inlet valve is closed. The pressure in the inner cavity is monitored by a pressure gauge: if the pressure does not drop, it indicates that the valve is tightly closed; if the pressure drops, it indicates that the sealing component needs to be replaced. The entire testing process does not require disassembling the valve, stopping the pipeline transportation, or additional pressure testing equipment.

[0036] This design completely changes the traditional blind valve maintenance mode, which requires disassembly before sealing testing can be performed. It significantly reduces maintenance labor intensity, shortens maintenance time, and improves equipment availability.

[0037] Third, the toxic and harmful fluids in the valve body cavity are forcibly discharged through high-pressure media. The entire process is accompanied by pressure monitoring and component detection to ensure thorough replacement, safety, and controllability, providing a safe working environment for subsequent valve maintenance or seal replacement. Introduce high-pressure isolation gas: Open the high-pressure isolation gas inlet valve and introduce nitrogen (or other inert gas / liquid) with a pressure higher than that of the conveying medium into the valve body cavity.

[0038] Discharge of toxic and harmful fluids: Open the drain valve at the bottom of the valve body and use the pressure of high-pressure gas to force out and discharge the toxic, harmful, flammable, explosive or corrosive fluids remaining in the inner cavity.

[0039] Replacement process control: Control the opening of the drain valve to always maintain the isolation sealing pressure in the valve body greater than the pressure of the conveying fluid, and prevent the conveying medium from seeping back into the inner cavity.

[0040] Displacement qualification judgment: Detect the concentration or composition of the discharged toxic and harmful fluids, and close the sewage gate after confirming that the replacement is qualified. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0042] Figure 1 This is a schematic diagram of the axial three-dimensional structure of the single-gate blind valve provided by the present invention.

[0043] Figure 2 for Figure 1 A longitudinal cross-sectional schematic diagram of a single-gate blind valve.

[0044] Figure 3 for Figure 2 A magnified schematic diagram of the structure of part A in the middle.

[0045] Figure 4 This is a schematic diagram of the first positioning ring.

[0046] Figure 5 This is a schematic diagram of the sliding seal sleeve drive component.

[0047] Figure 6 This is a schematic diagram of another embodiment of a single-gate blind valve.

[0048] Figure 7 This is a schematic diagram of the structure of the single-gate corrugated expansion blind valve provided by the present invention.

[0049] Figure 8 for Figure 7 A longitudinal cross-sectional schematic diagram of a single-gate corrugated expansion blind valve.

[0050] Figure 9 for Figure 8 A magnified schematic diagram of the structure of part B in the middle.

[0051] Figure 10 This is a schematic diagram of the structure of the single-gate anti-corrosion blind valve provided by the present invention.

[0052] Figure 11 for Figure 10 A longitudinal cross-sectional schematic diagram of a single-gate anti-corrosion blind valve.

[0053] Figure 12 This is a schematic diagram of the valve plate.

[0054] Figure 13 This is a schematic diagram of the structure of the single-gate airbag expansion blind valve provided by the present invention.

[0055] Figure 14 for Figure 13A longitudinal cross-sectional schematic diagram of a single-gate airbag expansion blind valve.

[0056] Figure 15 for Figure 14 A magnified schematic diagram of the structure of part C in the middle.

[0057] Figure 16 A schematic diagram of the structure of the double gate wedge blind valve provided by the present invention.

[0058] Figure 17 for Figure 16 A magnified schematic diagram of the structure of part D in the middle.

[0059] Figure 18 This is a schematic diagram of the structure of the T-head and T-slot.

[0060] Figure 19 This is a schematic diagram of the structure of the double-gate elliptical airbag blind valve provided by the present invention.

[0061] Figure 20 for Figure 19 A magnified schematic diagram of the structure of part E in the middle.

[0062] Figure 21 This is a schematic diagram of the second airbag.

[0063] Figure 22 for Figure 21 A magnified schematic diagram of the structure of part F in the middle.

[0064] Figure 23 This is a schematic diagram of an elliptical head push rod.

[0065] Figure 24 This is a schematic diagram of another embodiment of a double-gate elliptical airbag blind valve.

[0066] Figure 25 A schematic diagram of the axial three-dimensional structure of the double-gate double-airbag self-pressurized blind valve provided by the present invention.

[0067] Figure 26 for Figure 25 A diagram showing the protective casing concealed.

[0068] Figure 27 for Figure 25 A longitudinal cross-sectional schematic diagram.

[0069] Figure 28 for Figure 27 A magnified schematic diagram of the structure of a local part of G.

[0070] Figure 29 This is a schematic diagram of a dual-gate transverse drive.

[0071] Figure 30 for Figure 26A top-view diagram of the structure after the shell has been concealed.

[0072] Figure 31 for Figure 30 A magnified schematic diagram of the structure of H in the middle section.

[0073] Figure 32 A three-dimensional structural diagram of the spherical valve provided by the present invention.

[0074] Figure 33 for Figure 32 A schematic diagram showing the valve body after it has been concealed.

[0075] Figure 34 for Figure 32 A longitudinal cross-sectional schematic diagram.

[0076] Figure 35 for Figure 34 A magnified schematic diagram of the structure of part J in the middle.

[0077] Figure 36 A three-dimensional structural schematic diagram of the spherical airbag valve provided by the present invention.

[0078] Figure 37 for Figure 36 A longitudinal cross-sectional schematic diagram.

[0079] Figure 38 for Figure 37 A magnified schematic diagram of the structure of K in the middle section.

[0080] Figure 39 This is a schematic diagram of the fifth airbag.

[0081] Figure 40 This is a three-dimensional structural diagram of the spherical bellows valve provided by the present invention.

[0082] Figure 41 for Figure 40 A longitudinal cross-sectional schematic diagram.

[0083] Figure 42 for Figure 41 A magnified schematic diagram of the structure of a local L. Detailed Implementation

[0084] Embodiments of the present invention are described in detail below, examples of which are illustrated 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 the present invention, and should not be construed as limiting the present invention.

[0085] In the description of this invention, 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 invention 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 invention.

[0086] 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 invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0087] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," 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 invention according to the specific circumstances.

[0088] This invention discloses a blind valve combined sealing structure, including: a valve body 1, a valve seat 2 and a valve plate 3. The valve plate is placed in the inner cavity 101 of the valve body 1, and the valve seat 2 is placed in the flow channel 102 of the valve body 1. The valve seat 2 and the valve plate 3 are in sealing contact to form a seal. The outer peripheral wall of the valve seat 2 is provided with a first annular sealing groove 201. The first annular sealing groove 201 is filled with a sealing grease, such as butter or molybdenum disulfide, for sealing contact with the inner wall of the flow channel 102 of the valve body 1. The sealing grease is tightly filled in the tiny gap between the outer wall of the valve seat 2 and the inner wall of the valve body 1, forming a double static seal in the form of an oil film. The first inlet / outlet pipe 4 is connected to the inner cavity 101 and is used to pressurize the inner cavity 101 to achieve a high-pressure gas seal or for valve sealing tests. The first inlet / outlet pipe 4 is equipped with a first inlet valve 5 and a first exhaust valve 6. Thus, after the valves are closed, high-pressure inert gas (such as nitrogen) is pressurized into the inner cavity 101 through the first inlet / outlet pipe 4. The pressure is higher than that of the conveying medium, forming a three-stage pressure differential isolation seal. During testing, the inlet valve 5 is closed, and by monitoring whether the pressure in the inner cavity 101 drops, it can be determined online whether the overall seal has failed. If it fails, the valve assembly seal can be replaced, avoiding the need to remove the valve from the pipeline when pressure testing is required, reducing maintenance labor intensity and shortening maintenance time.

[0089] The technical effects of the combined sealing structure in the above embodiments are as follows: (1) Triple sealing synergy: It realizes the combination of grease static sealing between valve seat and valve body, differential pressure sealing in valve body cavity, and rigid sealing between valve seat and valve plate, which greatly improves the sealing performance of valve. (2) Filling micro-leakage: The sealing grease can adaptively fill the micro-unevenness that cannot be eliminated on the metal machining surface, eliminating the interface leakage between valve seat and valve body. (3) Maintenance without disassembly: The sealing performance can be verified by maintaining and monitoring air pressure without disassembling the valve, which greatly reduces the labor intensity and time of maintenance.

[0090] In some embodiments, a first annular sealing groove 202 is provided on both sides of the first annular sealing groove 201 on the outer peripheral wall of the valve seat 2. A first annular sealing ring (which may be made of rubber or PTFE and is not shown) is installed in each of the first annular sealing grooves 202 to prevent leakage of sealant.

[0091] The technical effects of this embodiment are as follows: (1) Preventing grease loss: It effectively solves the problem of grease being washed away or squeezed out under high pressure conditions, and extends the effective life of the grease. (2) Forming a sealed "oil reservoir": The sealing rings on both sides and the grease groove in the middle together form a long-term stable lubrication / sealing medium storage cavity. (3) Double safety protection: Even if the grease is gradually consumed, the elastic sealing rings on both sides can still provide basic contact sealing to prevent sudden leakage.

[0092] In some embodiments, the valve seat 2 has an elastic sealing element 7 (made of rubber or PTFE) and a rigid sealing pressure plate 8 on the side surface that is in sealing contact with the valve plate 3, both of which are in sealing contact with the sealing surface of the valve plate 3.

[0093] Initial Closure (Flexible Contact): When the valve plate approaches the valve seat, the first contact is made with the protruding elastic seal 7, such as rubber or PTFE. The elastic seal is compressed, forming the first seal and compensating for parallelism errors and minor unevenness between the valve plate 3 and the valve seat 2. Later Closure (Rigid Compression): As the closing force continues to be applied, the rigid sealing plate 8, such as titanium alloy or stainless steel, then fits tightly against the valve plate 3, forming the second high-pressure resistant and wear-resistant hard seal. Synergistic Effect: The elastic seal 7 is responsible for pre-sealing, and the rigid seal 8 is responsible for the main seal and erosion resistance.

[0094] The technical effects of this embodiment are as follows: (1) Complementary advantages: The soft seal (elastic) provides zero-leakage low-pressure sealing and tolerance; (2) The hard seal (rigid) provides high-pressure resistance, wear resistance and fluid erosion resistance. Extended service life: (3) The elastic seal protects the rigid sealing surface from initial impact and impurity scratches; the rigid seal can still maintain basic sealing after the elastic seal ages. (4) Wide operating condition adaptability: The combined sealing surface can simultaneously adapt to the harsh operating conditions of pressure fluctuations, temperature changes and media containing particles.

[0095] In some embodiments, the valve body 1 is provided with a pressure detector (existing product, not shown) for monitoring the pressure of the inner cavity 101, and the bottom end of the valve body 1 is provided with a drain pipe 9 communicating with the inner cavity 101. The drain pipe 9 is provided with a drain valve 10 and a flow monitor (existing product, not shown) for monitoring the fluid flow rate.

[0096] Replacement of toxic fluids (after closure): After the valve is closed, open the high-pressure isolation gas inlet valve. Open the drain valve 10, and use high-pressure gas to force out the remaining toxic, harmful, or flammable fluids in the inner cavity 101 through the drain pipe 9 at the bottom. The flow monitor detects the composition or flow rate of the discharged fluid in real time to determine whether the replacement is qualified.

[0097] Leakage monitoring (in operation): Maintain the air pressure in the inner cavity 101 higher than the pressure of the conveying medium. If leakage occurs between the valve plate 3 and the valve seat 2, the flow monitor on the drain pipe 9 will detect abnormal flow or medium, and the pressure detector will display abnormal fluctuations in the inner cavity pressure.

[0098] Sealing verification (during testing): Turn off the high-pressure air source and observe whether the internal cavity pressure drops using a pressure detector to determine if the combined seal has failed. If there is a slow drop and no external leakage is found, slightly open the drain valve 10 to check if any medium flows out, which can help locate the source of the leak.

[0099] Of course, audible and visual alarm values ​​can also be set, and signals can be transmitted to the control room in real time when the pressure or flow is abnormal, so as to realize remote intelligent monitoring of the valve.

[0100] It should be noted that the above-described combined sealing structure is applicable to single-gate valves, double-gate valves, spherical gate valves, and can also be applied to the sealing of other valves. The following embodiments of the structure for different valves are given respectively.

[0101] This invention provides a structural example of a single gate valve, which includes: The above-mentioned blind valve combination sealing structure has a valve plate 3 as a single gate plate and a valve seat 2 including: a first positioning ring 21 and two sliding sealing sleeves 22 respectively embedded in the inlet and outlet sides of the flow channel 102. The two first positioning rings 21 are arranged at intervals, and the two sliding sealing sleeves 22 are both located in the inner cavity 101 and are respectively sleeved on the two first positioning rings 21. The valve plate 3 can be placed between the two sliding sealing sleeves 22. Each of the two sliding sealing sleeves 22 is provided with an elastic sealing element 7 and a rigid sealing pressure plate 8 on the side facing the valve plate. The elastic sealing element 7 is sleeved on the sliding sealing sleeve 22, and the rigid sealing pressure plate 8 is sleeved on the outside of the elastic sealing element 7. Sliding sealing sleeve drive 11 is provided on valve body 1 and is used to drive two sliding sealing sleeves 22 to move, thereby making the elastic sealing element 7 and rigid sealing pressure plate 8 on the two sliding sealing sleeves 22 in sealing contact with the two sides of the single gate. A single gate drive cylinder 12 (which can be a hydraulic cylinder or a pneumatic cylinder) is mounted on the valve body 1. The telescopic end of the single gate drive cylinder 12 is fixed to the first valve stem 13 on the single gate plate, and is used to drive the single gate plate to rise and fall, so that the single gate plate moves in and out between the two first positioning rings 21. The outer peripheral wall of the first positioning ring 21 is provided with a first annular sealing groove 201 and a second annular sealing groove 203 that are interconnected. The first positioning ring 21 is provided with a sealant injection hole 211 that is connected to the first annular sealing groove 201 and the second annular sealing groove 203. The inner sleeve wall of the sliding sealing sleeve 22 is provided with a second annular sealing groove 221 on both sides of the second annular sealing groove 203. A second annular sealing ring is installed in each of the second annular sealing grooves 221 to prevent sealant leakage.

[0102] In conjunction with the above solutions, and see also Figures 1-5 The first embodiment of the present invention (single gate blind valve): There are two sliding seal sleeve drive components 11 arranged vertically, and each of the two sliding seal sleeve drive components 11 includes: Two first sliding sleeves 111 are arranged at intervals. The two first sliding sleeves 111 are slidably installed in the two sliding holes of the valve body 1, and one end of each of the two first sliding sleeves 111 is fixedly connected to one of the sliding sealing sleeves 22. Two first sliding rods 112 are arranged at intervals, and the two first sliding rods 112 are respectively inserted into two first sliding sleeves 111. One end of each of the two first sliding rods 112 is fixedly connected to another sliding sealing sleeve 22. The first inner connecting plate 113 is located on the outside of the valve body 1, and the first inner connecting plate 113 is fixedly connected to the other end of the two first sliding sleeves 111. The first outer connecting plate 114 is located outside the first inner connecting plate 113, and the first outer connecting plate 114 is fixedly connected to the other end of the two first sliding rods 112. The first telescopic cylinder 115 has its cylinder barrel fixed on the first outer connecting plate 114, and its first telescopic rod 1151 passes through the first outer connecting plate 114 and is fixedly connected to the first inner connecting plate 113.

[0103] In this embodiment, the valve closing process (sliding sealing sleeves moving in opposite directions) is as follows: the single gate drive cylinder 12 drives the valve plate 3 to descend to the closed position. The telescopic rod 1151 of the first telescopic cylinder 115 extends (pushing direction: from the first outer connecting plate 114 to the first inner connecting plate 113). Since the cylinder is fixed on the first outer connecting plate 114, when the telescopic rod extends: the first inner connecting plate 113 is pushed away from the first outer connecting plate 114. The first inner connecting plate 113 drives the two first sliding sleeves 111 to move away from the first outer connecting plate 114. The first sliding sleeves 111 push the sliding sealing sleeve 22 fixedly connected to them on one side to move towards the gate. At the same time, the first outer connecting plate 114 is subjected to the reaction force of the cylinder: the first outer connecting plate 114 drives the two first sliding rods 112 to move in opposite directions. The first sliding rods 112 drive the sliding sealing sleeve 22 fixedly connected to them on the other side to also move towards the gate. That is, the two sliding sealing sleeves 22 move synchronously towards each other, pressing the valve plate 3 from both sides. The elastic sealing element 7 (flexible seal, such as rubber / PTFE) first contacts the valve plate 3 and is compressed to form the first pre-seal, compensating for the parallelism error between the gate and the valve seat. The rigid sealing pressure plate 8 (rigid seal, such as titanium alloy / stainless steel) then adheres tightly to the side of the valve plate to form the second main seal. High-pressure isolation gas, higher than the pressure of the conveying medium, is introduced into the inner cavity 101 through the first inlet and outlet pipe 4 to form a pressure differential isolation seal. Through the sealant injection hole 211, sealant enters the first annular sealing groove 201 and the second annular sealing groove 203 to form a static seal.

[0104] In this embodiment, the valve opening process (sliding sealing sleeves moving in opposite directions) is as follows: The high-pressure isolation gas source is shut off and depressurized. Then, the telescopic rod 1151 of the first telescopic cylinder 115 retracts, pulling the first inner connecting plate 113 closer to the first outer connecting plate 114. The first sliding sleeve 111 is pulled back, causing one side of the sliding sealing sleeve 22 to disengage from the gate. The first outer connecting plate 114 causes the first sliding rod 112 to move in the opposite direction, causing the other side of the sliding sealing sleeve 22 to also disengage from the gate. That is, the two sliding sealing sleeves 22 move in opposite directions synchronously, forming a gap with the valve plate 3. Afterward, the single gate drive cylinder 12 drives the valve plate 3 to rise to the open position.

[0105] The beneficial effects of the above scheme are as follows: (1) In terms of combined sealing and leakage prevention, by setting the first and second annular sealing grooves and sealing grease injection holes that are interconnected on the first positioning ring, and cooperating with the second annular sealing rings located on both sides of the second annular sealing groove on the inner wall of the sliding sealing sleeve, a reliable interface sealing system is formed. The sealing grease is effectively sealed between the sealing rings on both sides, which not only fills the micro gap between the positioning ring and the sliding sealing sleeve, but also prevents the axial extrusion and loss of the grease under high pressure conditions. At the same time, the elastic sealing element (inner ring) and the rigid sealing pressure plate (outer ring) set on the sliding sealing sleeve achieve complementary advantages - the flexible seal is responsible for pre-sealing and compensating for assembly errors, while the rigid seal provides high pressure resistance and wear resistance as the main sealing capability, thereby constructing a double contact seal between the valve seat and the gate. (2) In terms of driving and anti-jamming, the two sliding sealing sleeve driving components arranged above and below adopt the cross linkage structure of telescopic cylinders, inner and outer connecting plates, sliding sleeves, and sliding rods, realizing the synchronous driving of the two sliding sealing sleeves to move towards or away from each other by a telescopic cylinder. This design not only ensures uniform force distribution and parallel contact of the sealing surfaces, but more importantly, when the valve is opened, the sealing sleeves on both sides are first released from the gate to form a gap, and then the gate is raised, thereby completely eliminating the tightness and friction between the sealing surfaces, effectively preventing the gate from jamming, greatly reducing the opening resistance and extending the life of the sealing components. At the same time, the gate is controlled by descending to the closed position in a free state and then pressing the seal, avoiding scratches on the sealing surfaces during the descent. Moreover, a telescopic cylinder is used to drive both sealing sleeves simultaneously (i.e., single-power bidirectional drive), which is compact, highly synchronized, and does not require separate control. Compared with the scheme of using cylinders on both sides, this driving method reduces the number of actuators, reduces control complexity and failure rate. (3) In terms of overall sealing reliability, this structure, based on rigid sealing, flexible sealing and grease sealing, further introduces high-pressure isolation gas higher than the pressure of the conveying medium into the valve body cavity through the inlet and outlet pipes to form a differential pressure isolation seal. The four seals work together to achieve absolute zero leakage after the valve is closed. In addition, the seal failure can be determined online by monitoring changes in the internal air pressure, eliminating the need to disassemble the valve for pressure testing, which significantly reduces maintenance labor intensity and time.

[0106] See Figure 6 The sliding sealing sleeve 22 has a first sealing surface annular groove 223 for filling with sealing grease on the side facing the valve plate 3. The sliding sealing sleeve 22 has a first flow channel 224 inside. One end of the first flow channel 224 is connected to the first sealing annular groove 223, and the other end of the first flow channel 224 is connected to one end of the grease injection follower tube 50. The other end of the grease injection follower tube 50 extends out of the valve body 1.

[0107] In this embodiment, the sealing grease can also be injected into the annular groove 223 of the first sealing surface through the grease injection follower tube 50 to achieve grease sealing with the valve plate 3, further improving the valve's sealing performance.

[0108] In conjunction with the above solutions, and see also Figures 7-9 The second embodiment of the present invention (single-gate corrugated expansion blind valve): Each sliding sealing sleeve drive component 11 includes two first bellows 116, which are respectively sleeved on the outer side of the two sliding sealing sleeves 22. One end of the first bellows 116 is fixedly connected to the inner wall of the inner cavity 101, and the other end is fixed to the outer wall of the sliding sealing sleeve 22. It also includes two second inlet and outlet pipes 117 disposed on the valve body 1. The two second inlet and outlet pipes 117 are respectively connected to the two first bellows 116 through air pipes. The second inlet and outlet pipes 117 are provided with a second inlet valve 118 and a second outlet valve 119.

[0109] The valve closing process in this embodiment: Gate Positioning: The single gate drive cylinder (switching cylinder) drives the valve stem and single gate to descend to the closed position in a free state, positioned between the two first positioning rings. Bellows Expansion and Compression: Open the second air inlet valves on the two second air inlet and exhaust pipes, and introduce high-pressure gas (or hydraulic oil) into the two first bellows. The first bellows expand, and since one end is fixed to the inner cavity wall and the other end is fixed to the sliding sealing sleeve, the expansion force pushes the two sliding sealing sleeves to slide towards each other along the first positioning rings. Sealing Contact: The elastic seals (flexible) on the two sliding sealing sleeves first contact the two sides of the gate and are compressed, forming the first pre-seal; then the rigid sealing plate presses tightly against the gate, forming the second main seal, cutting off the conveyed fluid. Establishing an Isolation Seal: After the valve is closed, high-pressure isolation gas higher than the pressure of the conveyed medium is introduced into the inner cavity through the first air inlet and exhaust pipes, forming a differential pressure isolation seal, and the sealing pressure is monitored by a pressure gauge.

[0110] The valve opening process in this embodiment: Bellows pressure relief disengagement: Close the second intake valve and open the second exhaust valve to release the pressure inside the first bellows. The first bellows retracts and resets, causing the two sliding sealing sleeves to slide in opposite directions, disengaging the elastic seal and rigid sealing plate from the gate surface, creating a gap. Gate lifting: The single gate drive cylinder drives the valve stem and valve plate to rise to the open position.

[0111] The bellows expansion drive has a buffering characteristic, resulting in minimal impact when the sealing sleeve presses against the gate, avoiding damage to the sealing surface from rigid collisions. It is particularly suitable for precision sealing applications where impact must be avoided. Moreover, compared to the complex mechanism of the telescopic cylinder, sliding sleeve, and inner and outer connecting plates in Embodiment 1, the bellows solution eliminates intermediate transmission components such as the sliding sleeve, sliding rod, and inner and outer connecting plates, with the drive component directly integrated into the valve body, significantly reducing the number of parts.

[0112] In conjunction with the above solutions, and see also Figures 10-12 The third embodiment of the present invention (single-gate anti-corrosion blind valve): The upper and lower parts of the valve plate 3 are a blind plate sealing surface 301 and a flow hole sealing surface 302, respectively. When the valve plate 3 descends, the flow hole sealing surface 302 is located in the receiving box 14 at the lower part of the valve body 1, and the blind plate sealing surface 301 cuts off the flow channel 102. The elastic seal 7 and the rigid sealing plate 8 are in sealing contact with the blind plate sealing surface 301. When the valve plate 3 rises, the flow hole sealing surface 302 on it is connected to the flow channel 102, and the elastic seal 7 and the rigid sealing plate 8 are in sealing contact with the flow hole sealing surface 302 to prevent corrosive fluid from entering the inner cavity 101.

[0113] The valve closing process in this embodiment: Gate descent and positioning: A single gate drive cylinder lowers the valve stem and valve plate. The blind plate sealing surface at the top of the valve plate enters the flow channel between the two first positioning rings, cutting off the fluid supply; the flow hole sealing surface at the bottom of the valve plate enters the receiving box at the bottom of the valve body. Sliding seal sleeve compression: The sliding seal sleeve drive component (telescopic cylinder linkage mechanism or bellows) is activated, causing the two sliding seal sleeves to move towards each other, making the elastic sealing element and rigid sealing pressure plate on them tightly contact the blind plate sealing surfaces on both sides of the valve plate, forming a double contact seal. Establishing an isolation seal: High-pressure isolation gas higher than the pressure of the conveyed medium is introduced into the inner cavity through the first inlet and outlet pipes, forming a pressure differential isolation seal. Open the drain pipe at the bottom of the valve body to discharge the original toxic, harmful, or corrosive fluid in the valve body. After the replacement is qualified, close the drain valve.

[0114] The valve opening process in this embodiment: Seal disengagement: The sliding seal sleeve drive reverses its movement, causing the two sliding seal sleeves to move in opposite directions, disengaging the elastic seal and rigid sealing plate from the blind plate sealing surface, creating a gap. Gate rises to flow position: The single gate drive cylinder drives the valve stem and valve plate to rise. The flow hole sealing surface at the bottom of the valve plate enters the flow channel between the two first positioning rings, aligning with the flow direction of the conveyed fluid. Secondary sealing of flow surface: The sliding seal sleeve drive moves again, causing the sliding seal sleeve to press against the flow hole sealing surfaces on both sides of the valve plate, ensuring tight contact between the elastic seal and rigid sealing plate and the flow hole sealing surfaces. Maintaining internal cavity isolation: High-pressure isolation gas is activated to maintain the internal cavity pressure higher than the conveyed fluid pressure. The drain valve is opened to displace and discharge residual corrosive fluid, preventing it from entering the internal cavity and corroding the valve body's internal structure. The flow hole sealing surface allows fluid to pass normally through the valve's central through-hole.

[0115] When the valve in this embodiment is closed, the blind flange sealing surface cuts off the fluid; when the valve is open, the flow hole sealing surface closes with the sliding sealing sleeve to prevent it from entering the inner cavity and corroding the valve body wall, valve stem and seals. It is particularly suitable for pipelines that transport highly corrosive media such as acids and alkalis.

[0116] Therefore, the upper part of the valve plate is a blind sealing surface, and the lower part is a flow passage sealing surface. A single valve plate simultaneously performs the dual functions of cutting off fluid flow when closed and isolating the internal cavity when open, resulting in a compact structure that requires no additional components. Furthermore, regardless of whether the valve is open or closed, the elastic seal and rigid sealing plate are always in contact with a certain sealing surface of the valve plate. Combined with the positive pressure protection of the high-pressure isolation gas, the metal components in the internal cavity (such as the valve stem, sliding sleeve, and connectors) never come into contact with the corrosive fluid being transported, significantly extending the overall service life of the valve. In addition, after valve switching, residual media in the internal cavity can be discharged through a drain pipe. During the replacement process, the internal cavity pressure is maintained higher than the pressure of the transported medium, ensuring that toxic, harmful, or corrosive fluids do not seep back into the internal cavity. Visual judgment of successful replacement is achieved through pressure and flow monitoring.

[0117] In conjunction with the above solutions, and see also Figures 13-15 The fourth embodiment of the present invention (single-gate airbag expansion blind valve): Each sliding sealing sleeve drive component 11 includes two first airbags 120. The two first airbags 120 are respectively fitted on the outer side of the two sliding sealing sleeves 22. Each first airbag 120 is disposed between the outer protrusion 222 on the sliding sealing sleeve 22 and the inner wall of the inner cavity 101. Each first airbag 120 is connected to the third intake and exhaust pipe 121 disposed on the valve body 1 through an air pipe. The third intake and exhaust pipe 121 is provided with a third intake valve 122 and a third exhaust valve 123.

[0118] The valve closing process in this embodiment: Gate Positioning: The single gate drive cylinder lowers the valve stem and single gate to the closed position in a free state, positioned between the two first positioning rings. Airbag Expansion and Compression: The third intake valves on the two third intake and exhaust pipes are opened, introducing high-pressure gas (isolation gas pressure higher than the conveying medium pressure) into the two first airbags. The first airbags expand; since the airbags are positioned between the outer convex plate on the sliding sealing sleeve and the inner wall of the cavity, the expansion force pushes the outer convex plate, thereby causing the two sliding sealing sleeves to slide towards each other along the first positioning rings. Sealing Contact: The elastic seals on the two sliding sealing sleeves first contact the two sides of the gate and are compressed, forming the first flexible pre-seal; subsequently, the rigid sealing pressure plate presses tightly against the gate, forming the second rigid main seal, cutting off the conveying fluid. Establishing an Isolation Seal: High-pressure isolation gas higher than the conveying medium pressure is introduced into the inner cavity through the first intake and exhaust pipes, forming a differential pressure isolation seal, and the sealing pressure is monitored by a pressure gauge.

[0119] The valve opening process in this embodiment: Airbag depressurization and disengagement: Close the third intake valve and open the two third exhaust valves to release the pressure inside the first airbag. The first airbag contracts and resets, losing its thrust on the outward-facing plate. At this time, the high-pressure isolation gas pressure pushes the sliding sealing sleeve to move in the opposite direction, causing the elastic seal and rigid sealing plate to disengage from the gate surface, forming a gap. Gate lifting: The single gate drive cylinder drives the valve stem and gate to rise to the open position.

[0120] Preferably, the first airbag 120 has at least a dual airbag structure, one as a working airbag and the other as a backup airbag.

[0121] Beneficial effects: In terms of operational reliability, the dual-bladder backup design fundamentally solves the problem of valve failure or sealing failure caused by the failure of a single bladed airbag. When the working bladed airbag malfunctions due to aging, damage, depressurization, or air circuit blockage after long-term use, there is no need to stop the machine and disassemble the valve. Simply switch the air circuit control system and put the backup airbag into operation, and the valve can continue to operate normally. This avoids unplanned shutdowns caused by drive component failures and significantly improves the operational reliability of the valve under continuous production conditions.

[0122] In terms of maintenance, the dual-bladder structure enables online repair. When the working blade fails, the backup blade takes over. This allows for replacement or repair of the failed blade without affecting the valve's normal opening, closing, and sealing functions, without interrupting the pipeline transport process, significantly reducing maintenance costs and production impact. Simultaneously, the dual-bladder design provides the valve with a longer maintenance-free cycle; the two blades can be used alternately, extending the overall lifespan of the drive system.

[0123] In terms of safety redundancy, for critical pipelines transporting flammable, explosive, toxic, harmful, or high-temperature and high-pressure fluids, airbag actuation failure directly affects equipment and personnel safety. The dual-airbag structure constitutes an intrinsically safe design; even if one airbag completely fails, the valve can still close normally and maintain a seal, providing ample time for handling emergencies and effectively avoiding leakage accidents caused by valve failure.

[0124] In terms of monitoring and early warning, the dual-airbag system can independently monitor the air pressure status of each airbag. When the working airbag experiences an abnormal pressure drop or fails to maintain pressure, the control room can receive an early warning signal, prompting the staff that the airbag has failed and needs to be replaced. At this time, the backup airbag has not yet been activated and is still in good condition, ensuring that the valve always has at least one usable driving airbag, achieving dual protection of failure early warning and continuous operation.

[0125] The dual gate valve provided by the present invention includes: The above-mentioned blind valve combination sealing structure has a valve plate 3 as a double gate with an inlet side gate 31 and an outlet side gate 32. The valve seat 2 includes: a second positioning ring 23 respectively embedded in the inlet and outlet sides of the flow channel 102, the two second positioning rings 23 are arranged at intervals, the outer peripheral wall of the second positioning ring 23 is provided with a first annular sealing groove 201, the elastic sealing element 7 is sleeved on the second positioning ring 23, and the rigid sealing pressure plate 8 is sleeved on the outside of the elastic sealing element 7. The double gate lifting drive cylinder 15 (which can be a hydraulic cylinder or a pneumatic cylinder) is mounted on the valve body 1. The telescopic end of the double gate lifting drive cylinder 15 is fixed to the second valve stem 16 on the double gate plate, and is used to drive the double gate plate to lift and move the double gate plate between the two second positioning rings 23. The double gate transverse movement drive 17 is installed on the valve body 1 and is used to drive the inlet side gate 31 and the outlet side gate 32 away from each other, so that the inlet side gate 31 and the outlet side gate 32 respectively make sealing contact with the elastic sealing element 7 and the rigid sealing pressure plate 8 on the two second positioning rings 23. The lower part of the second valve stem 16 is slidably connected to the T-slots 303 on the inlet-side gate 31 and the outlet-side gate 32 via the T-shaped head 161.

[0126] In conjunction with the above solutions, and see also Figures 16-18 The fifth embodiment of the present invention (double gate wedge blind valve): Both the inlet-side gate 31 and the outlet-side gate 32 have wedges 18 fixed on their adjacent sidewalls. The inclined surfaces of the two wedges 18 are arranged opposite each other. The double-gate lateral movement drive 17 includes: The first wedge-shaped push rod 171 passes through the second valve stem 16, and the lower end of the first wedge-shaped push rod 171 is the first push wedge 1711. The two inclined surfaces of the first push wedge 1711 abut against the inclined surfaces of the two wedge blocks 18, which are used to drive the inlet side gate 31 and the outlet side gate 32 to move away from each other. The push rod drive cylinder 172 is fixed on the telescopic end of the double gate lifting drive cylinder 15, and the telescopic end of the push rod drive cylinder 172 is fixedly connected to the upper end of the first wedge head push rod 171.

[0127] The valve closing process in this embodiment: Double gate descent and positioning: The double gate lifting drive cylinder drives the second valve stem and the double gates (inlet-side gate and outlet-side gate) to descend to the closed position in a free state, positioned between the two second positioning rings. At this time, the pressure of the conveying fluid presses the outlet-side gate against the second positioning ring on the outlet side, forming initial contact. Wedge-shaped push-and-slide seal: The push rod drive cylinder is activated, and its telescopic end pushes the first wedge-shaped head push rod downward within the second valve stem. The first push-and-slide wedge head moves downward accordingly, and its two inclined surfaces abut against and slide relative to the inclined surfaces on the two wedge blocks. As the wedge-shaped head push rod continues to move downward, the inclined surfaces of the wedge head force the two wedge blocks to move in opposite directions, thereby causing the inlet-side gate and the outlet-side gate to move away from each other and press against the second positioning rings on both sides of the inlet and outlet respectively. Combined sealing contact: The inlet-side gate and the outlet-side gate first contact and are compressed with the elastic seals (flexible seals) on the two second positioning rings, forming the first pre-seal; then the rigid sealing pressure plate presses tightly against the gate, forming the second rigid main seal, cutting off the conveying fluid. Establishing isolation and auxiliary sealing: High-pressure isolation gas, higher than the pressure of the conveyed medium, is introduced into the inner cavity through the first inlet and outlet pipes to form a pressure differential isolation seal. The pressure difference between the high-pressure gas and the conveyed fluid on the inlet side is used to further compress and seal the inlet-side gate. When the valve seal is not tight, sealant can be injected into the first annular sealing groove on the second positioning ring to seal the leakage point between the fixed valve seat and the gate.

[0128] The valve opening process in this embodiment: Wedge head disengagement: The push rod drive cylinder reverses its action, moving the first wedge head push rod upwards, causing the first pushing wedge head to disengage from the wedge block. At this point, the pushing force between the two wedge blocks disappears. Elimination of sealing tightness: The high-pressure isolation gas is shut off and depressurized. The pressure of the conveying fluid pushes the inlet-side gate away from the second positioning ring on the inlet side, creating a gap; the outlet-side gate also loosens due to the loss of wedge pushing force. Double gate free ascent: The double gate lifting drive cylinder drives the second valve stem and double gates to rise freely to the open position. Since the sealing surfaces have disengaged to create a gap, there is no friction or jamming during the ascent.

[0129] Beneficial effects: The inlet and outlet gates are pushed simultaneously to both sides by the same wedge-shaped push rod, achieving independent bidirectional sealing at both ends. This provides an additional sealing barrier compared to a single gate structure, resulting in higher safety. The wedge-shaped push rod is integrated inside the second valve stem, without occupying additional external space. The sliding connection between the T-shaped head and the T-slot ensures smooth gate lifting and lowering while allowing for horizontal lateral movement freedom with minimal motion interference.

[0130] In conjunction with the above solutions, and see also Figures 19-23 The sixth embodiment of the present invention (double-gate elliptical airbag blind valve): A second airbag 19 is fixed on the side wall of the inlet side gate 31 and the outlet side gate 32 that are close to each other. The second airbag 19 is U-shaped. The dual-gate transverse drive unit 17 includes: The elliptical head push rod 173 is inserted into the second valve rod 16, and the lower end of the elliptical head push rod 173 is an elliptical head 1731, which is placed in the U-shaped opening of the second airbag 19. The push rod drive component 174 (which can be a manual wrench, motor, etc.) is used to drive the elliptical head push rod 173 to rotate, so that the long axis side of the elliptical head 1731 pushes the inlet side gate 31 and the outlet side gate 32 away from each other. The elliptical push rod 173 has a first air supply channel 1732 inside. The upper end of the first air supply channel 1732 is equipped with a fourth intake and exhaust pipe 175. The fourth intake and exhaust pipe 175 is equipped with a fourth intake valve 176 and a fourth exhaust valve 177. The lower end of the first air supply channel 1732 is connected to the second airbag 19 through an air pipe.

[0131] Valve closing process: Dual gate descent and positioning: The dual gate lifting drive cylinder drives the second valve stem and dual gates (inlet-side gate and outlet-side gate) to descend to the closed position in a free state, positioned between the two second positioning rings. At this time, the pressure of the conveying fluid initially presses the outlet-side gate against the second positioning ring on the outlet side.

[0132] Elliptical head rotary push seal: The push rod drive (wrench or motor) drives the elliptical head push rod to rotate, causing the major axis of the elliptical head to change from the vertical direction (or the direction parallel to the gate) to the horizontal direction. The two ends of the major axis push against the inner walls of the two sides of the U-shaped second airbag, thereby pushing the inlet side gate and the outlet side gate away from each other, and pressing them against the combined sealing surfaces on the second positioning rings on both the inlet and outlet sides.

[0133] Airbag inflation assists in compression: Open the fourth air intake valve, and high-pressure gas is introduced into the U-shaped second airbag through the fourth air intake and exhaust pipe and the first air supply channel. The second airbag inflates and further pushes the gate plates to both sides, forming an auxiliary sealing force, so that the elastic sealing element and the rigid sealing pressure plate are in close contact with the gate plate, cutting off the fluid supply.

[0134] Establishing an isolation seal: High-pressure isolation gas, exceeding the pressure of the conveyed medium, is introduced into the inner cavity through the first inlet and outlet pipes to form a differential pressure isolation seal. When the valve seal is not tight, sealant can be injected into the first annular sealing groove on the second positioning ring through the valve body sealing hole to forcibly seal the leakage point.

[0135] Valve opening process: Airbag depressurization: The fourth intake valve is closed, and the fourth exhaust valve is opened, releasing the high-pressure gas inside the U-shaped second airbag. The airbag contracts, losing its auxiliary thrust on the two side gates. Elliptical head rotation disengagement: The push rod drive component reverses and rotates the elliptical head push rod 90°, causing the short axis of the elliptical head to turn horizontal. The long axis disengages from pushing the gates, creating a gap between the two side gates and the elliptical head. Elimination of sealing tightness: The high-pressure isolation gas is shut off and depressurized. The pressure of the conveying fluid pushes the inlet-side gate away from the second positioning ring on the inlet side, creating a gap; the outlet-side gate also loosens due to the loss of thrust. Double gate free rise: The double gate lifting drive cylinder drives the second valve stem and the double gates to rise freely to the open position.

[0136] Technical effects: (1) The elliptical head push rod only needs to rotate 90° to achieve strong pushing of the long shaft against the gate or disengagement of the short shaft. The driving component can be a manual wrench, motor or pneumatic device, which can adapt to the field conditions with / without power source and is flexible in operation. (2) The long shaft of the elliptical head provides basic mechanical lateral thrust, and the U-shaped airbag expands after inflation to provide additional uniform clamping force. The two work together, and even if the elliptical head has gaps due to wear, the airbag can still maintain the sealing clamping force. (3) The U-shaped airbag wraps around the elliptical head. When inflated, it not only pushes the gate to both sides, but also squeezes the elliptical head push rod to the center to form a self-locking, preventing the elliptical head from rotating on its own under vibration conditions and causing sealing failure. (4) When there is a high-pressure air source, the airbag can be used to assist in clamping and enhance the sealing effect; when there is no air source, reliable sealing can still be achieved by mechanical pushing of the elliptical head alone, which is suitable for field conditions with different power conditions.

[0137] The second airbag 19 has at least a dual-airbag structure, with one serving as the working airbag and the other as the backup airbag.

[0138] See Figure 24 Based on the above embodiments, it also includes a fluid delivery pipeline 60, one end of which is connected to the delivery pipeline 300 on the valve body 1, and the other end is connected to the fourth inlet and outlet pipeline 175. A fluid switching valve 70 is provided on the fluid delivery pipeline 60.

[0139] When there is no external high-pressure air source, the fluid switch valve 70 can be opened, so that the fluid in the delivery pipeline 300 enters the first air delivery channel 1732 through the delivery fluid pipeline 60 and enters the second air bag 19, which expands and pushes the gate plate to both sides to move the valve plate.

[0140] In conjunction with the above solutions, and see also Figures 25-31 The seventh embodiment of the present invention (double gate double airbag self-pressurizing blind valve): A third airbag 20 is fixed on the side wall of the inlet side gate 31 and the outlet side gate 32 that are close to each other, and both opposite sides of the inlet side gate 31 and the outlet side gate 32 have a protruding beam 24, and one side of each of the two opposite protruding beams 24 is provided with a wedge-shaped surface 241. The dual-gate transverse drive unit 17 includes: Two airbag linkage mechanisms 178 are installed on opposite side walls of valve body 1, and each airbag linkage mechanism 178 includes: The protective housing 1781 is fixed to one side wall of the valve body 1; U-shaped plate seat 1782 is disposed inside the protective housing 1781 and fixed on one side wall of the valve body 1; The airbag 1783 is pushed, and one side of the airbag 1783 is fixed to the inner wall of the U-shaped plate seat 1782. The fixing plate seat 1784 is disposed inside the protective housing 1781 and fixed on one side wall of the valve body 1; The reset airbag 1785 is fixed on one side of the fixed plate base 1784. A drive plate 1786 is fixed between the push airbag 1783 and the reset airbag 1785. A second wedge-shaped push rod 1787 is fixed on the drive plate 1786 at intervals. The second wedge-shaped push rod 1787 passes through the valve body 1, and the end of the second wedge-shaped push rod 1787 is a second push wedge head 17871. The two inclined surfaces of the second push wedge head 17871 abut against the two wedge surfaces 241, which are used to drive the inlet side gate 31 and the outlet side gate 32 to move away from each other. The fifth intake and exhaust pipe 1788 passes through the protective shell 1781 and is connected to the push airbag 1783 through an air pipe. The fifth intake and exhaust pipe 1788 is equipped with a fifth intake valve 1789 and a fifth exhaust valve 1790. The sixth intake and exhaust pipe 1791 is installed on the protective shell 1781 and is connected to the reset airbag 1785 through an air pipe. The sixth intake and exhaust pipe 1791 is equipped with a sixth intake valve 1792 and a sixth exhaust valve 1793. The second valve stem 16 has a second air supply channel inside. The upper end of the second air supply channel is connected to a seventh air intake and exhaust pipe 1794 through an air pipe. The seventh air intake and exhaust pipe 1794 is equipped with a seventh air intake valve 1795 and a seventh exhaust valve 1796. The lower end of the second air supply channel is connected to the third airbag 20 through an air pipe.

[0141] Valve closing process: Double gate descent and positioning: The double gate lifting drive cylinder drives the second valve stem and double gates to descend to the closed position, located between the two second positioning rings. The pressure of the conveying fluid initially presses the outlet-side gate against the second positioning ring on the outlet side. Push airbag expansion drives wedge head lateral movement: The fifth intake valve is opened, and high-pressure gas (which can utilize the pressure of the conveying medium itself or an external gas source) is introduced into the push airbag through the fifth intake and exhaust pipes, causing the airbag to expand and pushing the drive plate towards the center of the valve body. The drive plate then drives the second wedge head push rod to move inward through the valve body. The two inclined surfaces of the second push wedge head abut against and slide relative to the wedge surfaces on the two convex beams, forcing the two convex beams to move in opposite directions. This causes the inlet-side gate and outlet-side gate to move away from each other, pressing against the combined sealing surfaces on the second positioning rings on both sides. The third airbag inflates to assist in clamping: Opening the seventh air inlet valve allows high-pressure gas to be introduced into the third airbag, fixed between the two gates, through the seventh air inlet / outlet pipe and the second air supply channel. The third airbag inflates, pushing the gates to both sides, providing additional uniform clamping force. This ensures tight contact between the elastic seal and the rigid sealing plate and the gates, cutting off the fluid being transported. Establishing an isolation seal: High-pressure isolation gas, exceeding the pressure of the transported medium, is introduced into the inner cavity through the first air inlet / outlet pipe, forming a differential pressure isolation seal.

[0142] Valve opening process: Depressurizing the push airbag: Close the fifth intake valve and open the fifth exhaust valve to depressurize and contract the push airbag. Resetting airbag inflates and disengages: Open the sixth intake valve and introduce high-pressure gas into the reset airbag through the sixth intake and exhaust pipes. The reset airbag inflates, pushing the drive plate away from the valve body, causing the second wedge head push rod to retract outwards, disengaging the second push wedge head from the wedge surface on the convex beam, and the two side gates lose their lateral pushing force. Depressurizing the third airbag: Close the seventh intake valve and open the seventh exhaust valve to depressurize and contract the third airbag. The pressure of the supplied fluid pushes the inlet-side gate away from the second positioning ring on the inlet side, creating a gap. Double gates rise freely: The double gate lifting drive cylinder drives the second valve stem and the double gates to rise freely to the open position.

[0143] Preferably, the fifth inlet / exhaust pipe 1788, the sixth inlet / exhaust pipe 1791, and the seventh inlet / exhaust pipe 1794 are all connected to the gas transmission pipe 100 via pipe 200, which is connected to the valve body 1. This allows for self-pressure sealing using the pressure of the transported medium itself when there is no high-pressure gas source on site. This is particularly suitable for long-distance pipelines, unmanned stations, and other applications with high energy-saving requirements.

[0144] The push airbag 1783 and / or the reset airbag 1785 and / or the third airbag 20 are all at least a dual-airbag structure, one as the working airbag and the other as the backup airbag.

[0145] The spherical gate valve provided by the present invention includes: The above-mentioned blind valve combination sealing structure has a valve plate 3 as a spherical gate plate and a valve seat 2 including: movable sealing rings 25 respectively embedded in the inlet and outlet sides of the flow channel 102, two movable sealing rings 25 are arranged at intervals, a movable plate 26 is fixed on the outer peripheral wall of the movable sealing ring 25, and a first annular sealing groove 201 and two first annular sealing grooves 202 are provided on the outer wall of the movable sealing ring 25. The moving sealing ring lateral movement drive 27 is provided on the valve body 1 and is used to drive the two moving sealing rings 25 to move laterally, so that the inner ball sealing surface 251 of the two moving sealing rings 25 and the outer ball sealing surface 304 of the ball valve plate make sealing contact. The valve stem drive 28 (which can be a hydraulic cylinder or a pneumatic cylinder) is used to drive the third valve stem 29 on the spherical gate to rotate, so that the spherical valve plate opens or opens the flow channel 102.

[0146] In conjunction with the above solutions, and see also Figures 32-35 The eighth embodiment of the present invention (spherical valve): The moving seal ring lateral movement drive 27 includes: Two spaced-apart second sliding sleeves 271 are slidably installed in two sliding holes of valve body 1, and one end of each second sliding sleeve 271 is fixedly connected to one of the movable plates 26. Two spaced-apart second sliding rods 272 are respectively inserted into two second sliding sleeves 271, and one end of each second sliding rod 272 is fixedly connected to another movable plate 26. The second inner connecting plate 273 is located on the outside of the valve body 1, and the second inner connecting plate 273 is fixedly connected to the other end of the two second sliding sleeves 271. The second outer connecting plate 274 is located outside the second inner connecting plate 273, and the second outer connecting plate 274 is fixedly connected to the other end of the two second sliding rods 272. The second telescopic cylinder 275 has its cylinder barrel fixed on the second outer connecting plate 274, and its second telescopic rod 2751 passes through the second outer connecting plate 274 and is fixedly connected to the second inner connecting plate 273.

[0147] Valve closing process: Spherical gate rotation into position: The valve stem drive (manual wrench, motor, or pneumatic device) drives the third valve stem and spherical gate to rotate freely to the closed position, so that the outer spherical sealing surface of the spherical gate is directly opposite the inner spherical sealing surface of the two movable sealing rings, and the spherical gate blocks the flow channel. Movable sealing rings press against each other: The second telescopic cylinder is activated, and its second telescopic rod extends (pushing from the second outer connecting plate towards the second inner connecting plate). Since the cylinder is fixed to the second outer connecting plate, when the telescopic rod extends: the second inner connecting plate is pushed away from the second outer connecting plate, causing the two second sliding sleeves to move away from the second outer connecting plate, thereby pushing the movable plate and movable sealing ring fixedly connected to it on one side towards the spherical gate. The second outer connecting plate is subjected to the reaction force of the cylinder, causing the two second sliding rods to move in opposite directions, thereby causing the movable plate and movable sealing ring fixedly connected to it on the other side to also move towards the spherical gate. The two movable sealing rings move synchronously towards each other. Spherical sealing contact: The inner spherical sealing surfaces of the two movable sealing rings press synchronously against the outer spherical sealing surface of the spherical gate from both sides. The fit between the spherical surfaces has an automatic centering characteristic, ensuring uniform contact of the sealing pairs, forming a reliable rigid seal, and cutting off the conveyed fluid. Seal establishment and lubrication: Sealant is injected into the first annular sealing groove on the movable sealing ring through the grease injection hole, filling the microscopic gap between the movable sealing ring and the inner wall of the valve body. At the same time, lubricating oil is injected into the annular lubrication groove in the middle of the movable sealing ring through the valve body oil inlet hole, lubricating the sliding surface of the movable sealing ring. High-pressure isolation gas higher than the pressure of the conveyed medium is introduced into the inner cavity through the first inlet and outlet pipes to form a pressure differential isolation seal.

[0148] Valve opening process: Sealing ring disengagement: The second telescopic cylinder reverses its movement, the second telescopic rod retracts, and the second inner connecting plate moves closer to the second outer connecting plate. The second sliding sleeve is pulled back, causing one side of the movable sealing ring to disengage from the spherical gate; the second sliding rod moves in the opposite direction, causing the other side of the movable sealing ring to also disengage from the spherical gate. The two movable sealing rings move synchronously in opposite directions, forming a gap with the spherical gate and eliminating the tightness. Spherical gate rotation opening: After the high-pressure isolation gas is shut off and depressurized, the valve stem drive drives the third valve stem and the spherical gate to rotate freely to the open position, allowing fluid to pass through the flow channel.

[0149] In another embodiment, see further. Figure 35The inner wall of the inner spherical sealing surface 251 is provided with a second sealing surface annular groove 2511 for filling with sealant. The second sealing surface annular groove 2511 communicates with the first annular sealing groove 201. In this way, sealant can be filled into the second sealing surface annular groove 2511 to achieve sealant sealing with the outer spherical sealing surface 304, further improving the sealing performance of the ball valve.

[0150] In conjunction with the above solutions, and see also Figures 36-39 The ninth embodiment of the present invention (spherical airbag valve): The moving sealing ring transverse drive component 27 includes two fourth airbags 30. The two fourth airbags 30 are respectively sleeved on the outside of the two moving sealing rings 25, and each fourth airbag 30 is disposed between the moving plate 26 and the inner wall of the inner cavity 101. The fourth airbags 30 are connected to the eighth intake and exhaust pipes 33 disposed on the valve body 1 through air pipes. The eighth intake and exhaust pipes 33 are provided with an eighth intake valve 34 and an eighth exhaust valve 35. A fifth airbag 36 is provided between the two movable plates 26. The fifth airbag 36 is connected to the ninth intake and exhaust pipe provided on the valve body 1 through an air pipe. The ninth intake and exhaust pipe is provided with a ninth intake valve and a ninth exhaust valve.

[0151] Valve Closing Process: The spherical gate rotates into position: The valve stem drive rotates the third valve stem and the spherical gate to the closed position in a free state. The spherical gate blocks the flow channel, and its outer spherical sealing surface faces the inner spherical sealing surface of the two movable sealing rings. The fourth airbag expands, pushing the sealing rings to press tightly: The eighth inlet valve is opened, and high-pressure gas (the airbag inlet pressure is higher than the high-pressure isolation gas pressure, and the isolation gas pressure is higher than the conveying medium pressure) is introduced into the fourth airbag through the eighth inlet and outlet pipes. The fourth airbag expands; since the airbag is located between the movable plate and the inner wall of the cavity, the expansion force pushes the movable plate, thereby causing the two movable sealing rings to move axially towards each other, pressing the inner spherical sealing surfaces against the outer spherical sealing surfaces of the spherical gate from both sides, forming a reliable spherical rigid seal and cutting off the conveyed fluid. Seal Establishment and Lubrication: Sealant is injected into the first annular sealing groove on the movable sealing ring through the grease injection hole, filling the microscopic gap between the movable sealing ring and the inner wall of the valve body. High-pressure isolation gas higher than the conveying medium pressure is introduced into the inner cavity through the first inlet and outlet pipes, forming a differential pressure isolation seal.

[0152] Valve opening process: Fourth airbag depressurization: Close the eighth inlet valve and open the eighth exhaust valve, causing the fourth airbag to depressurize and contract, losing its thrust on the moving plate. Fifth airbag expansion pushes the sealing ring away: Open the ninth inlet valve to introduce high-pressure gas into the fifth airbag (or keep the fifth airbag inflated and utilize its expansion force). The fifth airbag expands, pushing the moving plate to both sides, causing the moving sealing ring to move in the opposite direction, causing the inner spherical sealing surface to disengage from the outer spherical sealing surface of the spherical gate, forming a gap and eliminating the tightness. Spherical gate rotation opening: After closing and depressurizing the high-pressure isolation gas, the valve stem drive drives the third valve stem and the spherical gate to rotate freely to the open position, allowing fluid to flow through the passage.

[0153] Preferably, the fourth airbag 30 and / or the fifth airbag 36 are at least a dual-airbag structure, one as a working airbag and the other as a backup airbag.

[0154] In conjunction with the above solutions, and see also Figures 40-42 The tenth embodiment of the present invention (spherical bellows valve): Each of the moving sealing ring transverse drive components 27 includes two second bellows 37, which are respectively sleeved on the outer side of the two moving sealing rings 25. One end of the second bellows 37 is fixedly connected to the inner wall of the inner cavity 101, and the other end is fixed to one side of the moving plate 26. It also includes two tenth inlet and outlet pipes 38 provided on the valve body 1. The two tenth inlet and outlet pipes 38 are respectively connected to the two second bellows 37 through air pipes. The tenth inlet and outlet pipes 38 are provided with a tenth inlet valve 39 and a tenth outlet valve 40.

[0155] Valve Closing Process: The spherical gate rotates into position: The valve stem drive rotates the third valve stem and the spherical gate to the closed position in a free state. The spherical gate blocks the flow channel, and its outer spherical sealing surface faces the inner spherical sealing surface of the two movable sealing rings. Bellows Expansion Pushes Sealing Rings Tightening: The tenth inlet valve is opened, and high-pressure gas is introduced into the second bellows through the tenth inlet / outlet pipe. The second bellows expands; since one end of the bellows is fixed to the inner cavity wall and the other end is fixed to the movable plate, the expansion force pushes the movable plate, thereby causing the two movable sealing rings to move axially towards each other. This causes the inner spherical sealing surfaces to press against the outer spherical sealing surface of the spherical gate from both sides, forming a reliable rigid spherical seal and cutting off the fluid transport. Seal Establishment and Lubrication: Sealant is injected into the first annular sealing groove on the movable sealing ring through the grease injection hole, filling the microscopic gap between the movable sealing ring and the inner wall of the valve body. High-pressure isolation gas higher than the pressure of the transported medium is introduced into the inner cavity through the first inlet / outlet pipe, forming a differential pressure isolation seal.

[0156] Valve opening process: Bellows depressurization and disengagement: Close the tenth inlet valve and open the tenth exhaust valve to release the pressure inside the second bellows. The second bellows retracts and resets, causing the moving plate and moving sealing ring to move in opposite directions, disengaging the inner spherical sealing surface from the outer spherical sealing surface of the spherical gate, creating a gap and eliminating the tightness. High-pressure isolation gas-assisted reset: As the bellows retracts, the high-pressure isolation gas pressure in the inner cavity assists in pushing the moving plate to move in the opposite direction, ensuring reliable disengagement of the sealing ring. Spherical gate rotation opening: After the high-pressure isolation gas is closed and depressurized, the valve stem drive drives the third valve stem and the spherical gate to rotate freely to the open position, allowing fluid to flow through the flow channel.

[0157] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0158] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A blind valve assembly sealing structure, characterized in that, include: The valve body (1), valve seat (2) and valve plate (3) are provided. The valve plate is placed in the inner cavity (101) of the valve body (1), and the valve seat (2) is placed in the flow channel (102) of the valve body (1). The valve seat (2) and the valve plate (3) are in sealed contact. The valve seat (2) has a first annular sealing groove (201) on its outer peripheral wall. The first annular sealing groove (201) is filled with sealing grease for sealing contact with the inner wall of the flow channel (102) of the valve body (1). The first intake and exhaust pipe (4) is connected to the inner cavity (101) and is used to fill the inner cavity (101) with gas to achieve high-pressure gas sealing or for valve sealing test. The first intake and exhaust pipe (4) is provided with a first intake valve (5) and a first exhaust valve (6).

2. The blind valve combination sealing structure according to claim 1, characterized in that, The valve seat (2) has a first annular sealing groove (202) on both sides of the first annular sealing groove (201) on its outer peripheral wall. The first annular sealing groove (202) is equipped with a first annular sealing ring to prevent the sealant from leaking.

3. The blind valve combination sealing structure according to claim 1, characterized in that, The valve seat (2) has an elastic sealing element (7) and a rigid sealing pressure plate (8) on the side surface that is in sealing contact with the valve plate (3).

4. The blind valve combination sealing structure according to claim 1, characterized in that, The valve body (1) is provided with a pressure detector for monitoring the pressure of the inner cavity (101). The bottom end of the valve body (1) is provided with a drain pipe (9) that communicates with the inner cavity (101). The drain pipe (9) is provided with a drain valve (10) and a flow monitor for monitoring the fluid flow rate.

5. A single gate valve, characterized in that, include: The blind valve combination sealing structure according to any one of claims 1-4, wherein the valve plate (3) is a single gate plate, and the valve seat (2) includes: a first positioning ring (21) and two sliding sealing sleeves (22) respectively embedded in the inlet and outlet sides of the flow channel (102), the two first positioning rings (21) are arranged at intervals, the two sliding sealing sleeves (22) are both located in the inner cavity (101) and respectively sleeved on the two first positioning rings (21), the valve plate (3) can be placed between the two sliding sealing sleeves (22), and each of the two sliding sealing sleeves (22) is provided with an elastic sealing element (7) and a rigid sealing pressure plate (8) on the side of the valve plate, the elastic sealing element (7) is sleeved on the sliding sealing sleeve (22), and the rigid sealing pressure plate (8) is sleeved on the outside of the elastic sealing element (7); Sliding sealing sleeve drive (11), the sliding sealing sleeve drive (11) is disposed on the valve body (1) and is used to drive the two sliding sealing sleeves (22) to move, thereby making the elastic sealing element (7) and rigid sealing pressure plate (8) on the two sliding sealing sleeves (22) in sealing contact with the two sides of the single gate. A single gate drive cylinder (12) is provided on the valve body (1). The telescopic end of the single gate drive cylinder (12) is fixed to the first valve stem (13) on the single gate, and is used to drive the single gate to rise and fall, so that the single gate can move in and out between the two first positioning rings (21). The first positioning ring (21) has a first annular sealing groove (201) and a second annular sealing groove (203) that are interconnected on its outer peripheral wall. The first positioning ring (21) has a sealant injection hole (211) that is connected to the first annular sealing groove (201) and the second annular sealing groove (203). The inner sleeve wall of the sliding sealing sleeve (22) has a second annular sealing groove (221) located on both sides of the second annular sealing groove (203). A second annular sealing ring is installed in each of the second annular sealing grooves (221) to prevent the sealant from leaking.

6. The single gate valve according to claim 5, characterized in that, The sliding sealing sleeve drive component (11) consists of two components arranged vertically, and each of the two sliding sealing sleeve drive components (11) includes: Two first sliding sleeves (111) are arranged at intervals. The two first sliding sleeves (111) are respectively slidably installed in the two sliding holes of the valve body (1). One end of each of the two first sliding sleeves (111) is fixedly connected to one of the sliding sealing sleeves (22). Two first sliding rods (112) are arranged at intervals, and the two first sliding rods (112) are respectively inserted into the two first sliding sleeves (111). One end of each of the two first sliding rods (112) is fixedly connected to the other sliding sealing sleeve (22). The first inner connecting plate (113) is located on the outside of the valve body (1), and the first inner connecting plate (113) is fixedly connected to the other end of the two first sliding sleeves (111). The first outer connecting plate (114) is located outside the first inner connecting plate (113), and the first outer connecting plate (114) is fixedly connected to the other end of the two first sliding rods (112). The first telescopic cylinder (115) has its cylinder barrel fixed on the first outer connecting plate (114), and the first telescopic rod (1151) of the first telescopic cylinder (115) passes through the first outer connecting plate (114) and is fixedly connected to the first inner connecting plate (113). or, The sliding sealing sleeve (22) has a first sealing surface annular groove (223) for filling with sealing grease on one side facing the valve plate (3). The sliding sealing sleeve (22) has a first flow channel (224) inside. One end of the first flow channel (224) is connected to the first sealing annular groove (223), and the other end of the first flow channel (224) is connected to one end of the grease injection follower tube (50). The other end of the grease injection follower tube (50) extends out of the valve body (1). or, Each sliding sealing sleeve drive component (11) includes two first bellows (116), which are respectively fitted onto the outer sides of the two sliding sealing sleeves (22). One end of the first bellows (116) is fixedly connected to the inner wall of the inner cavity (101), and the other end is fixed to the outer wall of the sliding sealing sleeve (22). It also includes two second inlet and outlet pipes (117) disposed on the valve body (1). The two second inlet and outlet pipes (117) are respectively connected to the two first bellows (116) via air pipes. The second inlet and outlet pipes (117) are provided with a second inlet valve (118) and a second outlet valve (119); or, The upper and lower parts of the valve plate (3) are a blind plate sealing surface (301) and a flow hole sealing surface (302), respectively. When the valve plate (3) descends, the flow hole sealing surface (302) on it is located in the receiving box (14) at the lower part of the valve body (1), and the blind plate sealing surface (301) cuts off the flow channel (102), and the elastic seal (7) and the rigid sealing plate (8) are in sealing contact with the blind plate sealing surface (301); when the valve plate (3) rises, the flow hole sealing surface (302) on it is connected to the flow channel (102), and the elastic seal (7) and the rigid sealing plate (8) are in sealing contact with the flow hole sealing surface (302) to prevent corrosive fluid from entering the inner cavity (101). or, Each of the sliding sealing sleeve drive components (11) includes two first airbags (120). The two first airbags (120) are respectively fitted on the outer side of the two sliding sealing sleeves (22). Each first airbag (120) is disposed between the outer protrusion plate (222) on the sliding sealing sleeve (22) and the inner wall of the inner cavity (101). Each first airbag (120) is connected to the third intake and exhaust pipe (121) disposed on the valve body (1) through an air pipe. The third intake and exhaust pipe (121) is provided with a third intake valve (122) and a third exhaust valve (123).

7. The single gate valve according to claim 6, characterized in that, The first airbag (120) has at least a dual airbag structure, one as a working airbag and the other as a backup airbag.

8. A double gate valve, characterized in that, include: The blind valve combination sealing structure according to any one of claims 1-4, wherein the valve plate (3) is a double gate with an inlet side gate (31) and an outlet side gate (32), and the valve seat (2) includes: a second positioning ring (23) respectively embedded in the inlet and outlet sides of the flow channel (102), the two second positioning rings (23) are arranged at intervals, the outer peripheral wall of the second positioning ring (23) is provided with the first annular sealing groove (201), the elastic sealing element (7) is sleeved on the second positioning ring (23), and the rigid sealing pressure plate (8) is sleeved on the outside of the elastic sealing element (7); A double gate lifting drive cylinder (15) is provided on the valve body (1). The telescopic end of the double gate lifting drive cylinder (15) is fixed to the second valve stem (16) on the double gate plate, and is used to drive the double gate plate to lift and lower, so that the double gate plate moves in and out between the two second positioning rings (23). A double gate lateral movement drive (17) is provided on the valve body (1) to drive the inlet gate (31) and the outlet gate (32) away from each other, so that the inlet gate (31) and the outlet gate (32) respectively make sealing contact with the elastic seals (7) on the two second positioning rings (23) and the rigid sealing pressure plate (8); The lower part of the second valve stem (16) is slidably connected to the T-slots (303) on the inlet side gate (31) and the outlet side gate (32) respectively via a T-shaped head (161).

9. The double gate valve according to claim 8, characterized in that, Both the inlet-side gate (31) and the outlet-side gate (32) have wedges (18) fixed on their adjacent sidewalls. The inclined surfaces of the two wedges (18) are arranged opposite each other. The double-gate transverse drive (17) includes: The first wedge-shaped push rod (171) is inserted into the second valve stem (16), and the lower end of the first wedge-shaped push rod (171) is the first push wedge head (1711). The two inclined surfaces of the first push wedge head (1711) abut against the inclined surfaces of the two wedge blocks (18) to drive the inlet side gate (31) and the outlet side gate (32) to move away from each other. A push rod drive cylinder (172) is fixed on the telescopic end of the double gate lifting drive cylinder (15), and the telescopic end of the push rod drive cylinder (172) is fixedly connected to the upper end of the first wedge-shaped push rod (171). or, A second airbag (19) is fixed on the side wall of the inlet side gate (31) and the outlet side gate (32) that are close to each other. The second airbag (19) is U-shaped. The dual-gate transverse drive (17) includes: Elliptical head push rod (173), the elliptical head push rod (173) is inserted in the second valve rod (16), and the lower end of the elliptical head push rod (173) is an elliptical head (1731), the elliptical head (1731) is placed in the U-shaped opening of the second airbag (19); A push rod drive (174) is used to drive the elliptical head push rod (173) to rotate, and to push the inlet side gate (31) and the outlet side gate (32) away from each other by the long axis of the elliptical head (1731). The elliptical head push rod (173) has a first air supply channel (1732) inside. The upper end of the first air supply channel (1732) is equipped with a fourth air intake and exhaust pipe (175). The fourth air intake and exhaust pipe (175) is provided with a fourth air intake valve (176) and a fourth exhaust valve (177). The lower end of the first air supply channel (1732) is connected to the second airbag (19) through an air pipe. It also includes a fluid delivery pipe (60), one end of which is connected to the delivery pipe (300) on the valve body (1), and the other end is connected to the fourth inlet and outlet pipe (175). A fluid switch valve (70) is provided on the fluid delivery pipe (60). or, A third airbag (20) is fixed on the side wall of the inlet side gate (31) and the outlet side gate (32) that are close to each other. Both sides of the inlet side gate (31) and the outlet side gate (32) have a protruding beam (24), and one side of each of the two protruding beams (24) is provided with a wedge-shaped surface (241). The dual-gate transverse drive (17) includes: Two airbag linkage mechanisms (178) are provided, which are respectively installed on two opposite side walls of the valve body (1). Each of the two airbag linkage mechanisms (178) includes: A protective housing (1781) is fixed to one side wall of the valve body (1); U-shaped plate seat (1782), the U-shaped plate seat (1782) is disposed inside the protective housing (1781) and fixed on one side wall of the valve body (1); A push airbag (1783) is fixed on one side of the inner wall of the U-shaped plate seat (1782); A fixing plate base (1784) is disposed inside the protective housing (1781) and fixed on one side wall of the valve body (1); A reset airbag (1785) is fixed on one side of the fixed plate base (1784); A drive plate (1786) is fixed between the push airbag (1783) and the reset airbag (1785). A second wedge-shaped push rod (1787) is fixed on the drive plate (1786) at intervals. The second wedge-shaped push rod (1787) passes through the valve body (1). The end of the second wedge-shaped push rod (1787) is a second push wedge head (17871). The two inclined surfaces of the second push wedge head (17871) abut against the two wedge surfaces (241) to drive the inlet side gate (31) and the outlet side gate (32) to move away from each other. The fifth intake and exhaust pipe (1788) passes through the protective shell (1781) and is connected to the push airbag (1783) through an air pipe. The fifth intake and exhaust pipe (1788) is provided with a fifth intake valve (1789) and a fifth exhaust valve (1790). The sixth intake and exhaust pipe (1791) passes through the protective shell (1781) and is connected to the reset airbag (1785) through an air pipe. The sixth intake and exhaust pipe (1791) is provided with a sixth intake valve (1792) and a sixth exhaust valve (1793). The second valve stem (16) has a second air supply channel inside. The upper end of the second air supply channel is connected to a seventh air intake and exhaust pipe (1794) through an air pipe. The seventh air intake and exhaust pipe (1794) is equipped with a seventh air intake valve (1795) and a seventh exhaust valve (1796). The lower end of the second air supply channel is connected to the third airbag (20) through an air pipe.

10. The double gate valve according to claim 9, characterized in that, The fifth intake and exhaust pipe (1788), the sixth intake and exhaust pipe (1791), and the seventh intake and exhaust pipe (1794) are all connected to the gas supply pipe (100) connected to the valve body (1) via pipe (200).

11. The double gate valve according to claim 9, characterized in that, The second airbag (19) is at least a dual-airbag structure, one as a working airbag and the other as a backup airbag. The push airbag (1783) and / or the reset airbag (1785) and / or the third airbag (20) are all at least dual-airbag structures, one as a working airbag and the other as a backup airbag.

12. A spherical gate valve, characterized in that, include: The blind valve combination sealing structure according to any one of claims 1, 2, and 4, wherein the valve plate (3) is a spherical gate, and the valve seat (2) includes: movable sealing rings (25) respectively embedded in the inlet and outlet sides of the flow channel (102), the two movable sealing rings (25) are arranged at intervals, a movable plate (26) is fixed on the outer peripheral wall of the movable sealing ring (25), and the outer wall of the movable sealing ring (25) is provided with a first annular sealing groove (201) and two first annular sealing ring grooves (202). The moving sealing ring lateral movement drive (27) is disposed on the valve body (1) and is used to drive the two moving sealing rings (25) to move laterally, thereby making the inner ball sealing surface (251) of the two moving sealing rings (25) and the outer ball sealing surface (304) of the ball valve plate in sealing contact. A valve stem drive (28) is used to drive the third valve stem (29) on the spherical gate to rotate, so that the spherical valve plate opens or opens the flow channel (102).

13. The spherical gate valve according to claim 12, characterized in that, The lateral movement drive (27) of the movable sealing ring includes: Two second sliding sleeves (271) are arranged at intervals. The two second sliding sleeves (271) are respectively slidably installed in the two sliding holes of the valve body (1). One end of each of the two second sliding sleeves (271) is fixedly connected to one of the moving plates (26). Two second sliding rods (272) are arranged at intervals, and the two second sliding rods (272) are respectively inserted into the two second sliding sleeves (271). One end of each of the two second sliding rods (272) is fixedly connected to the other movable plate (26). The second inner connecting plate (273) is located on the outside of the valve body (1), and the second inner connecting plate (273) is fixedly connected to the other end of the two second sliding sleeves (271); The second outer connecting plate (274) is located outside the second inner connecting plate (273), and the second outer connecting plate (274) is fixedly connected to the other end of the two second sliding rods (272); The second telescopic cylinder (275) has its cylinder barrel fixed on the second outer connecting plate (274), and its second telescopic rod (2751) passes through the second outer connecting plate (274) and is fixedly connected to the second inner connecting plate (273). or, The moving sealing ring transverse drive component (27) includes two fourth airbags (30). The two fourth airbags (30) are respectively sleeved on the outside of the two moving sealing rings (25), and each fourth airbag (30) is disposed between the moving plate (26) and the inner wall of the inner cavity (101). The fourth airbags (30) are connected to the eighth intake and exhaust pipes (33) disposed on the valve body (1) through air pipes. The eighth intake and exhaust pipes (33) are provided with an eighth intake valve (34) and an eighth exhaust valve (35). A fifth airbag (36) is provided between the two movable plates (26). The fifth airbag (36) is connected to the ninth inlet and outlet pipe provided on the valve body (1) through an air pipe. The ninth inlet and outlet pipe is provided with a ninth inlet valve and a ninth outlet valve. or, Each of the moving sealing ring transverse drive components (27) includes two second bellows (37), which are respectively sleeved on the outer side of the two moving sealing rings (25). One end of the second bellows (37) is fixedly connected to the inner wall of the inner cavity (101), and the other end is fixed to one side of the moving plate (26). It also includes two tenth intake and exhaust pipes (38) provided on the valve body (1). The two tenth intake and exhaust pipes (38) are respectively connected to the two second bellows (37) through air pipes. The tenth intake and exhaust pipes (38) are provided with a tenth intake valve (39) and a tenth exhaust valve (40).

14. The spherical gate valve according to claim 13, characterized in that, The fourth airbag (30) and / or the fifth airbag (36) are at least dual airbag structures, one as a working airbag and the other as a backup airbag.

15. The spherical gate valve according to claim 13, characterized in that, The inner wall of the inner ball sealing surface (251) is provided with a second sealing surface annular groove (2511) for filling with sealant grease. The second sealing surface annular groove (2511) is connected to the first annular sealing groove (201).

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