A valve pressurized plugging clamp and a plugging method thereof

Abstract

The present application relates to the technical field of pipeline leak stoppage under pressure without stopping transmission, and discloses a valve leak stoppage clamp under pressure, which comprises a clamp shell, a connecting mechanism and a glue injection unit, the clamp shell is provided as at least two, the two clamp shells are symmetrically arranged and have consistent length-width specifications, the inner walls of the two clamp shells are each provided with an inner lining fixing plate, the inner lining fixing plate is made of flexible material and has a profiled light wall on the inner surface, and the outer side of the inner lining fixing plate is fixedly connected with the inner wall of the corresponding clamp shell, a dovetail groove is formed in the interior of each clamp shell, and a sealing ring is arranged in the dovetail groove, the present application is provided with a pressure linkage valve between the hydraulic drive mechanism and the glue injection pipeline, so that the hydraulic cylinder pre-tightening force is synchronously increased when the glue injection pressure is increased, the radial expansion deformation of the clamp shell is effectively resisted, the inflation ring and the fixing ring are arranged, the internal space area is divided by driving the inflation ring to move by using the control screw rod, and the compressibility of the gas in the inflation ring is used to absorb the curing stress of the sealant, so that secondary leakage is prevented.

Description

Technical Field

[0001] This invention relates to the field of pipeline live-line leak sealing technology, and particularly to a valve live-line leak sealing fixture and its leak sealing method. Background Technology

[0002] Valves are indispensable control components in pipeline transportation systems, widely used in industries such as petroleum, chemical, power, and metallurgy. During long-term operation, valve bodies and their connections often leak due to media corrosion, erosion, aging of seals, or manufacturing defects. Since pipelines often transport flammable, explosive, toxic, or high-temperature and high-pressure fluids, leaks not only cause material loss and environmental pollution but can also lead to serious safety accidents.

[0003] Currently, there are two main methods for handling valve leaks: shutdown for replacement and live plugging. Shutdown for replacement requires cutting off pipelines and discharging the medium, which not only affects production continuity but also causes huge economic losses. Therefore, live plugging technology is widely used due to its advantages of not requiring shutdown and quick construction. Existing live plugging fixtures usually adopt a two-part structure. The fixture is fastened to the outside of the leak by bolts, and then sealant is injected into the fixture to achieve a seal.

[0004] Chinese patent CN108223959A discloses a live leak sealing device and method for root valves, belonging to the field of live leak sealing technology for pipelines without interrupting operation. The device includes: a lower flange fitted at the connection between the root valve body and the pressure tapping pipe; a sleeve fitted outside the root valve body, with an upper flange at the lower end of the sleeve along the circumferential direction; a polytetrafluoroethylene (PTFE) plug located between the sleeve and the root valve body, with the PTFE plug and the sleeve having an interference fit; and a sealing grease coating applied between the PTFE plug and the outer surface of the PTFE plug and the root valve body.

[0005] Existing pressurized leak-sealing fixtures still have the following shortcomings in practical applications: First, the valve body has an irregular shape and includes complex structures such as flanges, valve covers, and transition fillets, making it difficult for the inner wall of traditional fixtures to fit completely, resulting in uneven filling of the sealant and poor sealing effect; Second, the fixture is subjected to a large radial expansion force during the injection process, which can easily cause elastic deformation, leading to an increase in the sealing gap and causing secondary leakage; Third, the volume shrinkage or expansion stress generated during the curing process of the sealant cannot be effectively released, which can easily lead to sealing failure after long-term service. Summary of the Invention

[0006] The purpose of this invention is to provide a valve pressure-sealing clamp to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a valve pressurized leak-sealing clamp, comprising a clamp housing, a connecting mechanism, and an adhesive injection unit. The connecting mechanism is disposed on the outer surface of the clamp housing and is used to fix the clamp housing to the outside of the valve body. The adhesive injection unit is disposed on the outer surface of the clamp housing and is used to inject adhesive into the interior of the clamp housing to form a seal to seal the leaking valve body. At least two clamp housings are provided, which are symmetrically arranged and have the same length and width specifications. The inner walls of both clamp housings are provided with inner lining plates. The inner lining plates are made of flexible material and have a contoured smooth wall on the inner surface. The outer side of the inner lining plates is fixedly connected to the inner wall of the corresponding clamp housing. Each clamp housing has a dovetail groove inside, and a sealing ring is provided inside the dovetail groove.

[0008] The connecting mechanism includes multiple hydraulic drive mechanisms symmetrically distributed circumferentially along the fixture housing. Each hydraulic drive mechanism includes a hydraulic cylinder and a piston rod. The hydraulic cylinder is fixed to the outer wall of the fixture housing, and the end of the piston rod faces the adjacent fixture housing. The other fixture housing has a connector corresponding to the position of the piston rod. The connector includes a sleeve and a nut. The inner diameter of the sleeve is adapted to the diameter of the piston rod. The piston rod is inserted into the sleeve. The outer side of the piston rod has a thread adapted to the nut. The thread is locked by screwing the nut on. The piston rod applies force perpendicular to the mating surface of the fixture housing, applying a radial preload to press the two fixture housings together to resist radial expansion deformation caused by the injection pressure.

[0009] Preferably, the inner wall surface of the inner lining plate is provided with an inflation ring and a fixing ring, the outer side of the inflation ring is slidably connected to the inner wall of the inner lining plate, and the outer side of the fixing ring is fixedly connected to the inner wall of the inner lining plate.

[0010] Preferably, the inflation ring is internally threaded with a control screw, which extends along the inside of the inflation ring toward the fixed ring and through the fixed ring, extending to the outside of the fixed ring; the inflation ring is internally connected to an air supply pipe, which extends along the fixed ring and through the fixed ring, extending to the outside of the fixed ring; when the control screw rotates, it drives the inflation ring to move horizontally along the inner wall of the inner lining plate.

[0011] Preferably, the inner wall of the inner lining plate is provided with at least one guide groove along the axial direction, and the outer edge of the air ring is provided with a guide slider that cooperates with the guide groove; flexible sealing strips are embedded on both sides of the guide groove, and the outer edge of the air ring and the flexible sealing strip always maintain interference contact to maintain regional isolation and sealing during the sliding process of the air ring.

[0012] Preferably, the two ends of the control screw are supported on the end walls of the fixed ring and the inner liner plate by bearing seats, respectively, so as to control the screw to rotate circumferentially and be fixed axially.

[0013] Preferably, the connecting mechanism further includes clamp ear plate A, clamp ear plate B and clamp ear plate C, clamp ear plate A and clamp ear plate B are symmetrically arranged on the left and right sides of the clamp housing, and clamp ear plate C is located at the bottom of the clamp housing; the surfaces of clamp ear plate A, clamp ear plate B and clamp ear plate C are all provided with multiple mounting holes, and all three are welded and fixed to the surface of the clamp housing.

[0014] Preferably, the glue injection unit includes multiple glue injection tubes A, B, and C. Multiple glue injection tubes A are located on the top of the fixture housing, multiple glue injection tubes B are symmetrically located on the left and right sides of the fixture housing, and multiple glue injection tubes C are located on the bottom outer side of the fixture housing. Glue injection tubes A, B, and C are all connected to the interior of the fixture housing. The end of the glue injection unit is equipped with an external glue injection device, and the diameter of the input end of the external glue injection device is adapted to the diameter of glue injection tubes A, B, and C, respectively.

[0015] Preferably, both the glue injection tube A and the glue injection tube B are provided with dovetail grooves, both of which penetrate the clamp housing and the sealing ring and are connected to the inside of the dovetail grooves; the outer sides of the glue injection tubes A, B and C are provided with self-locking structures to lock the output end of the external glue injection equipment to prevent it from coming out.

[0016] Preferably, the self-locking structure includes a self-locking base, the bottom of which is connected to the surface of the clamp housing; multiple limiting cranks are distributed around the top circumference of the self-locking base, and a docking pipe is provided in the middle; a rotating ring with internal threads is rotatably connected to the outer end of the docking pipe, and the rotating ring is threadedly connected to an external glue injection device; a self-locking ring is slidably sleeved on the outer side of the limiting cranks, and multiple pneumatically driven push rods are distributed around the bottom circumference of the self-locking ring, the inner cavity of the pneumatically driven push rods communicating with the interior of the self-locking base; multiple cavities with cavities are provided on the inner wall of the docking pipe, and the cavities of the cavities are connected with the interior of the self-locking base.

[0017] This invention also provides a method for sealing leaks using a valve pressurized sealing clamp, comprising the following steps:

[0018] S1. Cover the outside of the leakage valve body with two symmetrically arranged clamp housings, align the mating surfaces of the two clamp housings, insert the piston rods of each hydraulic drive mechanism into the connecting sleeves of the corresponding clamp housings, and tighten the nuts to complete the initial connection and fixation of the two sets of clamp housings. The inner lining plate of the inner wall of the clamp housing is attached to the outer wall surface of the valve body.

[0019] S2. Start the hydraulic drive mechanism, the piston rod applies a preload force perpendicular to the mating surface of the clamp housing, and presses the two sets of clamp housings together; inject sealant into the inside of the clamp housing through the glue injection unit;

[0020] S3. Continue injecting sealant until the internal cavity of the clamp is filled with sealant, maintain the preset pressure until the sealant is completely cured, and complete the pressurized sealing of the leaking valve body.

[0021] The technical effects and advantages of this invention are as follows:

[0022] 1. This invention achieves simultaneous increase of hydraulic cylinder preload when the injection pressure rises by setting a pressure linkage valve between the hydraulic drive mechanism and the glue injection pipeline, effectively resisting radial expansion deformation of the fixture shell; by setting an inflation ring and a fixed ring, the internal space area is divided by using a control screw to drive the inflation ring to move, and the compressibility of the gas in the inflation ring is used to absorb the curing stress of the sealant and prevent secondary leakage.

[0023] 2. This invention employs a self-locking structure, utilizing a rotating ring threaded connection for initial connection. A pneumatically driven push rod then drives the self-locking ring, causing the limiting crank to retract inwards while the protrusion expands outwards, forming a double locking mechanism to prevent the glue injection device from detaching. Furthermore, by directly connecting injection pipes A and B to the dovetail groove, the sealant preferentially fills the gap between the sealing ring and the pipes, forming the first sealing barrier. Injection pipe C serves as a vent to ensure full filling. Pressure data measurement determines the uniformity of glue injection. When pressure is abnormal, an inflatable ring expands to form a temporary seal. A control screw drives the inflatable ring to reciprocate, squeezing the glue into small gaps, achieving closed-loop compensation for glue injection quality and improving sealing reliability. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0025] Figure 2 This is a front view of the overall structure of the present invention;

[0026] Figure 3 This is a cross-sectional view of the overall structure of the present invention;

[0027] Figure 4 This is a schematic diagram of the assembly state of the sleeve, nut, and hydraulic drive mechanism of the present invention;

[0028] Figure 5 This is a top view of the overall structure of the present invention;

[0029] Figure 6 This is a schematic diagram of the installation state of the connecting pipe, rotating ring, and external adhesive injection equipment of the present invention.

[0030] Figure 7 This is a schematic diagram of the self-locking ring and related structures of the present invention.

[0031] In the diagram: 1. Fixture housing; 101. Dovetail groove; 102. Sealing ring; 103. Inner lining plate; 104. Inflatable ring; 105. Fixing ring; 106. Control screw; 107. Air supply pipe; 2. Connecting mechanism; 201. Hydraulic drive mechanism; 202. Sleeve; 203. Nut; 204. Fixture ear plate A; 205. Fixture ear plate B; 206. Fixture ear plate C; 3. Glue injection unit; 301. Glue injection pipe A; 302. Glue injection pipe B; 303. Glue injection pipe C; 304. Self-locking base; 305. Limiting crank; 306. Connecting pipe; 307. Rotating ring; 308. External glue injection equipment; 309. Self-locking ring; 310. Pneumatic drive push rod; 311. Protrusion. Detailed Implementation

[0032] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0033] This invention provides, for example Figures 1 to 7 The valve pressure plugging fixture shown includes a fixture housing 1, a connecting mechanism 2, and an adhesive injection unit 3. The connecting mechanism 2 is located on the outer surface of the fixture housing 1 and is used to connect the fixture housing 1 to the outside of the valve body. The adhesive injection unit 3 is located on the outer surface of the fixture housing 1 and is used to inject adhesive into the interior of the fixture housing 1 to form a seal and achieve the purpose of plugging the leaking valve body.

[0034] The number of fixture housings 1 is at least two, and the two fixture housings 1 are arranged symmetrically to each other. The length and width of the two fixture housings 1 are the same. The inner wall of the two fixture housings 1 is provided with an inner lining plate 103. The outer side of the two inner lining plates 103 is connected to the inner wall of the two fixture housings 1. The inner lining plates 103 are made of flexible material and the surface of the inner lining plates 103 is set as a contoured smooth wall. The interior of each fixture housing 1 is provided with a dovetail groove 101, and the interior of the dovetail groove 101 of each fixture housing 1 is provided with a sealing ring 102.

[0035] The connecting mechanism 2 includes a hydraulic drive mechanism 201. The hydraulic drive mechanism 201 can be an injection hydraulic rod. There are multiple hydraulic drive mechanisms 201, which are symmetrically distributed on the left and right sides of the fixture housing 1.

[0036] It should be noted that the hydraulic drive mechanism 201 includes a hydraulic cylinder and a piston rod. The hydraulic cylinder is fixed to the outer wall of the clamp housing 1. The end of the piston rod points towards the adjacent clamp housing 1. The other clamp housing 1 has a connecting piece in the area corresponding to the piston rod. The connecting piece includes a sleeve 202 and a nut 203. The nut 203 is movably connected to the outer side of the sleeve 202. The inner diameter of the sleeve 202 is compatible with the diameter of the piston rod, meaning the piston rod can be inserted into the sleeve 202. The outer side of the piston rod is provided with a connection to the nut 203. The matching threads, along with the rotation of the nut 203, achieve a threaded connection. Then, the hydraulic drive mechanism 201 is evenly distributed along the circumference of the clamp housing 1, and the force direction of the piston rod is perpendicular to the mating surface of the clamp housing 1. By applying radial preload, the two clamp housings 1 are pressed together to resist the radial expansion deformation caused by the injection pressure. Furthermore, a one-way valve or pressure linkage valve is provided between the hydraulic circuit of the hydraulic drive mechanism 201 and the injection pipeline, so that when the injection pressure increases, the hydraulic cylinder is automatically triggered to increase the pressure, achieving the linkage effect of "the greater the pressure, the stronger the preload".

[0037] An inflation ring 104 and a fixing ring 105 are respectively provided on the surface of the inner wall of the inner lining plate 103. The outer side of the inflation ring 104 is slidably connected to the inner wall of the inner lining plate 103, and the outer side of the fixing ring 105 is fixedly connected to the inner wall of the inner lining plate 103. A control screw 106 is threadedly connected to the inside of the inflation ring 104. The control screw 106 extends along the inside of the inflation ring 104 toward the fixing ring 105 and passes through the fixing ring 105 and is located on the outside of the fixing ring 105. An air supply pipe 107 extends from the inside of the inflation ring 104 and is interconnected with the inside of the inflation ring 104. The end of the air supply pipe 107 away from the inflation ring 104 extends toward the fixing ring 105 and passes through the fixing ring 105 and is located on the outside of the fixing ring 105. When the control screw 106 rotates, the inflation ring 104 moves horizontally along the inner wall of the inner lining plate 103.

[0038] It should be noted that: the inner wall of the inner lining plate 103 has one or more guide grooves (not shown in the figure) axially, and the outer edge of the air ring 104 has guide sliders (not shown in the figure) that cooperate with the grooves. Furthermore, on both sides of the guide grooves, the inner wall of the inner lining plate 103 is embedded with flexible sealing strips (such as PTFE or fluororubber strips, not shown in the figure). The outer edge of the air ring 104 and the sealing strips always maintain interference contact, ensuring that the air ring 104 can maintain the isolation and sealing between areas during sliding. Additionally, the air ring 104 has a threaded through hole at its center. The control screw 106 passes through this threaded through hole and is threadedly connected to the air ring 104. The two ends of the control screw 106 are supported by bearing seats on the end walls of the fixed ring 105 and the inner lining plate 103, respectively. The screw can only rotate and cannot move axially. Therefore, when the control screw 106 is rotated, the air ring 104 moves axially along the screw under the threaded drive.

[0039] The connecting mechanism 2 also includes clamp ear plates A204, B205, and C206. Clamp ear plates A204 and B205 are symmetrically arranged on one side of the clamp housing 1 on the left and right sides. Clamp ear plate C206 is located at the bottom of the clamp housing 1. Multiple mounting holes are opened on the surface of clamp ear plates A204, B205, and C206. One side of clamp ear plates A204, B205, and C206 is welded and fixed to the surface of the clamp housing 1.

[0040] The glue dispensing unit 3 includes glue dispensing tubes A301, B302, and C303. Multiple glue dispensing tubes A301, B302, and C303 are provided. Multiple glue dispensing tubes A301 are located at the top of the fixture housing 1. Multiple glue dispensing tubes B302 are symmetrically arranged on the left and right sides of the fixture housing 1. Multiple glue dispensing tubes C303 are located at the bottom and top of the outer side of the fixture housing 1. 3 is interconnected with the interior of the fixture housing 1. The outer sides of the glue injection tubes A301, B302 and C303 are all equipped with self-locking structures. The self-locking structures are used to lock the output end of the external glue injection device 308 to prevent it from coming out. The glue injection tubes A301 and B302 are located on the outer surface of the fixture housing 1 near the dovetail groove 101. The glue injection tubes A301 and B302 pass through the fixture housing 1 and the sealing ring 102 and are interconnected with the interior of the dovetail groove 101.

[0041] The self-locking structure includes a self-locking base 304, the bottom of which is connected to the surface of the fixture housing 1. A limiting crank 305 is provided on the top of the self-locking base 304. Multiple limiting cranks 305 are provided and are circumferentially distributed on the top of the self-locking base 304. A docking pipe 306 is provided in the middle of the self-locking base 304. The diameter of the docking pipe 306 is adapted to the output end of the external glue injection device 308. A rotating ring 307 is provided at one end of the docking pipe 306 near the external glue injection device 308. The rotating ring 307 is rotatably connected to one end of the docking pipe 306. The inner diameter surface of the rotating ring 307 is threaded and is adapted to the input end of the external glue injection device 308.

[0042] Multiple limiting cranks 305 are slidably provided with self-locking rings 309 on their outer sides. The self-locking rings 309 are in active contact with the outer surfaces of the multiple limiting cranks 305. Multiple pneumatic drive push rods 310 are provided on the side of the self-locking ring 309 facing the self-locking base 304. The multiple pneumatic drive push rods 310 are circumferentially arranged at the bottom of the self-locking ring 309. The cavities inside the pneumatic drive push rods 310 are interconnected with the interior of the self-locking base 304. Multiple protrusions 311 are provided on the inner wall of the docking pipe 306. The protrusions 311 have cavities inside. The interiors of the protrusions 311 are interconnected with the interior of the self-locking base 304 through the docking pipe 306.

[0043] First, during use, place the two symmetrically arranged clamp housings 1 on the outside of the valve body and the pipes on both sides, aligning the length and width of the two clamp housings 1, and align the inner lining plate 103 towards the valve body and pipe surfaces. The inner lining plate 103 is made of flexible material and has a contoured smooth wall surface, so it can initially conform to the irregular surfaces of the valve body (including flanges, valve covers, and transition fillets) during the fastening process, reducing the initial gap.

[0044] Subsequently, the two clamp housings 1 are initially fixed by the clamp ear plates A204, B205, and C206 in the connecting mechanism 2 and their mounting holes. At this time, the control screw 106 is rotated, causing it to rotate and advance along the inside of the inflation ring 104 towards the fixed ring 105, driving the inflation ring 104 to move horizontally along the inner wall of the inner lining plate 103. Since the fixed ring 105 is located on the outward side of the clamp housing 1 (close to the outer wall of the clamp housing 1), and the inflation ring 104 is located in the area close to the valve body, the rotation of the control screw 106 can precisely adjust the axial position of the inflation ring 104 within the clamp housing 1. By adjusting the position of the inflation ring 104, the internal space of the clamp housing 1 can be divided into different areas: the area between the inflation ring 104 and the fixed ring 105 corresponds to the straight pipe section, while the area between the two symmetrically arranged inflation rings 104 corresponds to the valve body section, thus achieving independent management of different sealing areas.

[0045] Next, gas is injected into the inflation ring 104 through the gas supply pipe 107. After the inflation ring 104 expands, it applies radial pressure to the inner wall of the inner lining plate 103, forcing the inner lining plate 103 to further adhere to the valve body and the pipe surface. At the same time, it squeezes the sealing ring 102 in the dovetail groove 101, causing the sealing ring 102 to undergo elastic deformation and fit tightly against the outer wall of the pipe and the irregular corners of the valve body, thereby pre-sealing most of the gap leakage channels before the glue is injected.

[0046] After the pre-sealing is completed, the hydraulic drive mechanism 201 (injection hydraulic rod) in the connection mechanism 2 is activated. The hydraulic drive mechanism 201 is symmetrically distributed on the left and right sides of the fixture housing 1. By applying a controllable radial preload, the fixture housing 1 and the inner lining plate 103 are pressed together as a whole, while counteracting the structural deformation trend that may occur during the subsequent glue injection process.

[0047] Next, the glue injection operation is performed. The output end of the external glue injection device 308 is inserted into any of the interfaces of glue injection tubes A301, B302, or C303. Taking glue injection tube A301 as an example, the output end of the external glue injection device 308 is inserted into the docking pipe 306. The rotating ring 307 is rotated, and the threads of the rotating ring 307 and the input end of the external glue injection device 308 are matched and tightened to achieve a preliminary connection. Subsequently, under the action of the rotating ring 307, the input end of the external glue injection device 308 enters the docking pipe 306 and compresses the surface of the protrusion 311. The gas in the protrusion 311 is input into the pneumatic drive rod through the docking pipe 306 and the self-locking base 304, and is in an extended state. The pneumatic drive push rod 310 drives the self-locking ring 309 to slide upwards along multiple limiting cranks 305. Since the central area of ​​the multiple limiting cranks 305 is raised, the multiple self-locking rings... 309 applies pressure to one end of the external glue injection device 308 until the self-locking ring 309 presses against the limiting crank 305, causing it to retract inward and lock the output end of the external glue injection device 308 inside the docking pipe 306; at the same time, the internal cavities of multiple protrusions 311 on the inner wall of the docking pipe 306 are connected to the pneumatic drive push rod 310 through the self-locking base 304, and the air pressure causes the protrusions 311 to expand outward, further locking the output end of the external glue injection device 308 and preventing it from coming off due to high pressure impact during the glue injection process.

[0048] During sealant injection, the sealant injection tube A301 located at the top of the fixture housing 1 and the sealant injection tubes B302 located on the left and right sides are preferentially selected for injection, because both injection tubes A301 and B302 penetrate the fixture housing 1 and the sealing ring 102 and are interconnected with the inside of the dovetail groove 101. The sealant first enters the dovetail groove 101 area through injection tubes A301 and B302, filling the tiny gap between the sealing ring 102 and the outer wall of the pipe, forming the first sealing barrier. Subsequently, the sealant diffuses along the dovetail groove 101 towards the injection cavity in the middle section (valve body section) of the fixture, gradually filling the irregular gaps between the contoured smooth wall of the inner lining plate 103 and the outer contour of the valve body. During this process, the sealant injection tube C303 located at the bottom of the fixture housing 1 can be used as a venting or overflow observation hole. When the sealant flows out from the injection tube C303, it indicates that the injection cavity is basically full, and then the self-locking structure of the injection tube C303 is closed.

[0049] During the glue injection process, the hydraulic drive mechanism 201 works continuously, and the pre-tightening force is increased synchronously according to the increase of the glue injection pressure, so that the fixture housing 1 always maintains sufficient radial stiffness, preventing the fixture housing from elastically deforming (bulging) due to the increase of internal pressure, thereby avoiding the sudden increase of the sealing gap and causing secondary leakage.

[0050] When the sealant is fully injected and begins to cure, the shrinkage or expansion of the sealant volume will generate stress inside the fixture. At this time, the gas pre-filled in the inflation ring 104 has a certain elastic buffering capacity, which can absorb part of the curing stress and reduce the tendency of the fixture housing 1 to separate due to stress concentration, thereby effectively preventing secondary leakage. At the same time, the area division formed between the inflation ring 104 and the fixing ring 105 allows the sealant in the pipeline section and the valve body section to cure independently without interference, further improving the reliability of the sealing.

[0051] It should be noted that sealants undergo volume shrinkage (common in silicone sealants, with a shrinkage rate of approximately 1% to 5%) or volume expansion (e.g., when exposed to high-temperature media) during the curing process. This generates axial or radial residual stress within the fixture. Secondly, the gas inside the inflation ring 104 is compressible. When the sealant cures and generates axial stress, the inflation ring 104 can undergo a slight elastic displacement along the axial direction, absorbing some energy through the compression deformation of the gas, thereby reducing the separation force acting on the end face and mating surface of the fixture housing 1. Furthermore, the initial inflation pressure of the inflation ring 104 should be adjusted according to the type of sealant and the expected curing stress, generally between 0.2 and 0.5 MPa.

[0052] Finally, after all the injection tubes have finished injecting the sealant and the self-locking structure has been closed, maintain the pressure for a period of time and wait for the sealant to fully cure, thus completing the pressurized sealing of the leaking valve body.

[0053] Secondly, after the glue injection operation in all areas is completed and the pressure holding stage begins, the operator uses the external glue injection device 308 to measure the pressure data of glue injection tubes A301, B302, and C303 respectively. The external glue injection device 308 connects to each glue injection tube through a self-locking structure and reads the real-time pressure value of each tube port.

[0054] If the pressure data deviation values ​​of the three injection tubes A301, B302 and C303 are all within the preset allowable range (e.g., ±5%), it indicates that the internal injection is uniform and there are no local voids or underfilling. At this time, no treatment is required, and pressure is maintained until the sealant is completely cured.

[0055] It should be noted that the preset deviation value is determined based on the type of sealant, the volume of the injection cavity, and the injection pressure level (the cavity inside the fixture filled with sealant). For conventional silicone sealants, the allowable pressure deviation between each injection tube is ±5% to ±10% (relative value). The specific determination method is as follows: Before formal construction, take the same batch of sealant and conduct an injection test in a simulated fixture, record the pressure data of each injection tube under ideal filling conditions, and use this as the benchmark deviation value. Alternatively, an empirical formula can be used: preset deviation value ≤ 10% of the rated pressure of the injection pump.

[0056] If the pressure data measured by one of the dispensing tubes (e.g., dispensing tube A301 or dispensing tube B302) is significantly higher than the average of the other two dispensing tubes, exceeding the preset deviation value, it indicates that the dispensing in that area is uneven, with localized glue accumulation or flow obstruction. In this case, different compensation measures need to be taken depending on the type of the area:

[0057] Scenario 1: The area with abnormal pressure is the straight pipeline area (corresponding to the area between the inflation ring 104 and the fixed ring 105, i.e. the area governed by the glue injection tube A301 or the glue injection tube B302).

[0058] First, an appropriate amount of gas is introduced into the inflation ring 104 through the gas supply pipe 107 connected to the area, causing the inflation ring 104 to expand and fit tightly against the outer surface of the straight pipe, forming a temporary seal to prevent the adhesive from leaking from this side during subsequent extrusion operations.

[0059] Subsequently, the control screw 106 is rotated to drive the inflation ring 104 to move laterally and reciprocally along the horizontal direction inside the fixture housing 1 (i.e., to move towards the fixed ring 105 and then back). During this process, the inflation ring 104 acts like a piston, repeatedly squeezing and releasing the adhesive in the area between the inflation ring 104 and the fixed ring 105, forcing the adhesive to penetrate and fill smaller gaps (such as the microscopic gap between the sealing ring 102 and the pipe, and the irregular gap between the inner lining plate 103 and the valve body) under high pressure.

[0060] After several reciprocating compressions, the inflation ring 104 is reset to its initial position using the control screw 106. Then, glue is injected again through the glue injection tube (A or B) in this area until the pressure difference between the glue injection tube and the pressure data of the other two glue injection tubes falls back to the preset range.

[0061] Scenario 2: The area with abnormal pressure is the valve body area between the two inflation rings 104 (corresponding to the area governed by the injection tube C303).

[0062] First, an appropriate amount of gas is simultaneously introduced into the two inflation rings 104 through the gas supply pipes 107 on both the left and right sides, so that the two inflation rings 104 expand and come into close contact with the outer surface of their respective straight pipes, forming two reliable sealing barriers to isolate the valve body area from the pipe areas on both sides.

[0063] Next, the control screws 106 on both sides are rotated simultaneously, driving the two air rings 104 to move synchronously towards the center of the fixture housing 1 (i.e., the valve body area). The two air rings 104 approach each other, applying bidirectional pressure to the adhesive in the valve body area, forcing the adhesive into all the small gaps on the valve body surface (such as the flange root, valve cover fillet, casting defects, etc.) under high pressure.

[0064] After compression, the two inflation rings 104 are reset to their initial positions using the control screw 106. Subsequently, glue is added through the glue injection tube C303 in the valve body area until the difference between the pressure data of the glue injection tube C303 and the pressure data of the glue injection tubes A301 and B302 is within the preset range.

[0065] After the above targeted compensation operations, the injection pressure in all areas tends to be consistent, indicating that the sealant has fully filled all potential leakage channels. At this point, continue to maintain the pressure and wait for the sealant to fully cure, thus completing the entire pressurized sealing operation.

[0066] It should be noted that after the inflation ring 104 is reset, some of the gas inside the inflation ring 104 should be released through the gas supply pipe 107 first, so that the inflation ring 104 contracts slightly and restores the glue injection channel between it and the pipe surface. This prevents the inflation ring 104 from blocking the flow of glue during glue replenishment. Secondly, a step-by-step pressure increase method should be used when replenishing glue: first inject at a low pressure (about 50% of the original glue injection pressure) and observe whether the pressure gauge reading rises steadily; after confirming that there is no abnormality, increase to the original glue injection pressure for final filling. Finally, after the replenishment is completed, inflate the inflation ring 104 again to the initial pressure to restore the area isolation state.

[0067] This invention also provides a method for sealing leaks using a valve pressurized sealing clamp, comprising the following steps:

[0068] S1. Cover the outside of the leakage valve body with two symmetrically arranged clamp housings 1, align the mating surfaces of the two clamp housings 1, insert the piston rods of each hydraulic drive mechanism 201 into the connecting sleeves 202 of the corresponding clamp housing 1, and tighten the nuts 203 to complete the initial connection and fixation of the two sets of clamp housings 1. The inner lining plate 103 of the inner wall of the clamp housing 1 is attached to the outer wall surface of the valve body.

[0069] S2. Start the hydraulic drive mechanism 201, the piston rod applies a pre-tightening force perpendicular to the mating surface of the clamp housing 1, press the two sets of clamp housings 1 together, and inject sealant into the interior of the clamp housing 1 through the glue injection unit 3.

[0070] S3. Continue injecting sealant until the internal cavity of the clamp is filled with sealant, maintain the preset pressure until the sealant is completely cured, and complete the pressurized sealing of the leaking valve body.

[0071] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A valve pressure sealing clamp, comprising a clamp housing (1), a connecting mechanism (2), and an adhesive injection unit (3), characterized in that: At least two clamp housings (1) are provided, and the two clamp housings (1) are symmetrically arranged and have the same length and width specifications; the inner walls of the two clamp housings (1) are provided with inner lining plates (103), the inner lining plates (103) are made of flexible material and the inner surface is a contoured smooth wall, and the outer side of the inner lining plates (103) is fixedly connected to the inner wall of the corresponding clamp housing (1); each clamp housing (1) is provided with a dovetail groove (101) inside, and a sealing ring (102) is provided inside the dovetail groove (101). The connecting mechanism (2) includes multiple hydraulic drive mechanisms (201), which are symmetrically distributed around the circumference of the fixture housing (1). Each hydraulic drive mechanism (201) includes a hydraulic cylinder and a piston rod. The hydraulic cylinder is fixed to the outer wall of the fixture housing (1), and the end of the piston rod faces the adjacent fixture housing (1). The other fixture housing (1) is provided with a connector corresponding to the position of the piston rod. The connector includes a sleeve (202) and a nut (203). The inner diameter of the sleeve (202) is adapted to the diameter of the piston rod. The piston rod is inserted into the sleeve (202). The outer side of the piston rod is provided with a thread adapted to the nut (203). The thread is locked by screwing the nut (203). The direction of the piston rod force is perpendicular to the mating surface of the fixture housing (1). A radial preload is applied to press the two fixture housings (1) together to resist the radial expansion deformation caused by the injection pressure.

2. The valve pressure-sealing clamp according to claim 1, characterized in that: The inner wall surface of the inner lining plate (103) is provided with an inflation ring (104) and a fixing ring (105). The outer side of the inflation ring (104) is slidably connected to the inner wall of the inner lining plate (103), and the outer side of the fixing ring (105) is fixedly connected to the inner wall of the inner lining plate (103).

3. A valve pressure-sealing clamp according to claim 2, characterized in that: The inflation ring (104) is internally threaded with a control screw (106). The control screw (106) extends along the inside of the inflation ring (104) toward the fixed ring (105) and passes through the fixed ring (105), and extends to the outside of the fixed ring (105). The inflation ring (104) is internally connected with an air supply pipe (107). The air supply pipe (107) extends along the direction of the fixed ring (105) and passes through the fixed ring (105), and extends to the outside of the fixed ring (105). When the control screw (106) rotates, it drives the inflation ring (104) to move horizontally along the inner wall of the inner lining plate (103).

4. A valve pressure-sealing clamp according to claim 3, characterized in that: The inner wall of the inner lining plate (103) is provided with at least one guide groove along the axial direction. The outer edge of the air ring (104) is provided with a guide slider that cooperates with the guide groove. Flexible sealing strips are embedded on both sides of the guide groove. The outer edge of the air ring (104) and the flexible sealing strip always maintain interference contact to maintain regional isolation and sealing during the sliding process of the air ring (104).

5. A valve pressure-sealing clamp according to claim 3, characterized in that: The two ends of the control screw (106) are supported by bearing seats on the end walls of the fixed ring (105) and the inner lining plate (103), respectively, so that the control screw (106) can rotate circumferentially and be fixed axially.

6. A valve pressure-sealing clamp according to claim 1, characterized in that: The connecting mechanism (2) further includes clamp ear plate A (204), clamp ear plate B (205) and clamp ear plate C (206). The clamp ear plate A (204) and clamp ear plate B (205) are symmetrically arranged on the left and right sides of the clamp housing (1). The clamp ear plate C (206) is located at the bottom of the clamp housing (1). The surfaces of the clamp ear plate A (204), clamp ear plate B (205) and clamp ear plate C (206) are all provided with multiple mounting holes, and all three are welded and fixed to the surface of the clamp housing (1).

7. A valve pressure-sealing clamp according to claim 1, characterized in that: The glue injection unit (3) includes glue injection tube A (301), glue injection tube B (302) and glue injection tube C (303), and there are multiple of each of the three. Multiple glue injection tubes A (301) are located on the top of the fixture housing (1), multiple glue injection tubes B (302) are symmetrically located on the left and right sides of the fixture housing (1), and multiple glue injection tubes C (303) are located on the bottom of the outside of the fixture housing (1). Glue injection tubes A (301), B (302) and C (303) are all connected to the inside of the fixture housing (1). The end of the glue injection unit (3) is provided with an external glue injection device (308). The diameter of the input end of the external glue injection device (308) is adapted to the diameter of glue injection tube A (301), glue injection tube B (302) and glue injection tube C (303) respectively.

8. A valve pressure-sealing clamp according to claim 7, characterized in that: The glue injection tube A (301) and glue injection tube B (302) are both provided corresponding to the dovetail groove (101). Both of them pass through the clamp housing (1) and the sealing ring (102) and are connected to the inside of the dovetail groove (101). The outer sides of the glue injection tube A (301), glue injection tube B (302) and glue injection tube C (303) are all provided with a self-locking structure to lock the output end of the external glue injection device (308) to prevent it from coming out.

9. A valve pressure-sealing clamp according to claim 8, characterized in that: The self-locking structure includes a self-locking base (304), the bottom of which is connected to the surface of the fixture housing (1); multiple limiting cranks (305) are distributed around the top circumference of the self-locking base (304), and a docking pipe (306) is provided in the middle. A rotating ring (307) with internal threads is rotatably connected to the outer end of the docking pipe (306), and the rotating ring (307) is threadedly connected to an external glue injection device (308); a self-locking ring (309) is slidably sleeved on the outer side of the limiting cranks (305), and multiple pneumatic drive push rods (310) are distributed around the bottom circumference of the self-locking ring (309). The inner cavity of the pneumatic drive push rod (310) is connected to the inside of the self-locking base (304); multiple cavities of the protrusions (311) are provided on the inner wall of the docking pipe (306), and the cavities of the protrusions (311) are connected to the inside of the self-locking base (304).

10. A method for sealing leaks using a valve pressure-sealing clamp, implemented using the valve pressure-sealing clamp as described in claim 1, characterized in that... Includes the following steps: S1. Cover the outside of the leakage valve body with two symmetrically arranged clamp housings (1), align the mating surfaces of the two clamp housings (1), insert the piston rods of each hydraulic drive mechanism (201) into the connecting sleeves (202) of the corresponding side clamp housing (1), tighten the nuts (203) to complete the initial connection and fixation of the two sets of clamp housings (1), and the inner lining plate (103) of the inner wall of the clamp housing (1) fits against the outer wall surface of the valve body; S2. Start the hydraulic drive mechanism (201), the piston rod applies a preload force perpendicular to the mating surface of the clamp housing (1), and presses the two sets of clamp housings (1) together; inject sealant into the interior of the clamp housing (1) through the glue injection unit (3); S3. Continue injecting sealant until the internal cavity of the clamp is filled with sealant, maintain the preset pressure until the sealant is completely cured, and complete the pressurized sealing of the leaking valve body.

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