On-line diagnosis of seal performance in pipe connections, seal structure, device and method

Abstract

The application discloses a kind of pipeline joint sealing performance on-line diagnosis sealing structure, device and method, the sealing structure includes two opposite plane sealing sections and two opposite half-ring sealing sections;Plane sealing section and half-ring sealing section are alternately connected, and a closed and integrally formed frame structure is surrounded;Plane sealing section has split surface;Half-ring sealing section has wedge-shaped sealing flange at both ends, and at least two annular sealing grooves are formed on the inner circumferential surface.When two sealing structures are split, the opposite split surfaces are attached to each other to achieve open and close plane sealing, the opposite sealing flanges are extruded to each other to strengthen the end surface sealing, the opposite two half-ring sealing sections are split into a circular channel and wrapped around the pipeline, and the at least two annular sealing grooves form a labyrinth curved surface seal with the outer wall surface of the pipeline.The sealing structure of the application eliminates the leakage hazards of plane and plane, plane and curved surface transition area, and curved surface and curved surface from the structure, and can achieve full-area, non-discontinuous and non-blind area sealing from plane to curved surface.

Description

Technical Field

[0001] This invention relates to the field of sealing performance testing technology, and in particular to a sealing structure, device and method for online diagnosis of the sealing performance of pipeline joints. Background Technology

[0002] In pipeline systems, the sealing performance of joints is crucial. For scenarios requiring external testing of the sealing performance of installed joints, a wrap-around device is typically used to create a sealed testing chamber around the joint. However, this wrap-around device itself faces complex sealing challenges when mating with the pipes at both ends of the joint and its open section.

[0003] Traditional sealing methods generally employ a split-type composite structure: a flat sealing gasket is used on the central opening, while split O-rings or split square sealing gaskets are used at both ends of the pipe. This structure, which uses multi-layered overlapping and splicing at the transition between the flat surface and the curved pipe surface, has inherent defects. Specifically, the multi-layered overlapping and misaligned interfaces in the connection area create a natural weak sealing zone. Under assembly compression, pressure fluctuations, and structural deformation, this area is prone to problems such as incomplete fit, localized arching, uneven gaps, and cracking and separation of the split interfaces. Furthermore, traditional structures lack adaptive deformation compensation capabilities, making it extremely difficult to achieve effective sealing in the transition area between the flat and curved surfaces, leading to frequent leakage problems. They also suffer from drawbacks such as easy misalignment during disassembly and assembly, repeated disassembly and assembly causing failure, and short service life. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a sealing structure, device and method for online diagnosis of the sealing performance of pipeline joints.

[0005] The technical solution adopted by the present invention to solve its technical problem is: to construct a sealing structure for sealing the opening and closing surfaces of two assembled bodies and sealing the outer wall contact surface of the pipe penetrating the two assembled bodies, including two opposing planar sealing sections and two opposing semi-annular sealing sections; the planar sealing sections are located on opposite sides, and the semi-annular sealing sections are located at both ends, the four forming a closed and integrally formed frame structure. The planar sealing section has a mating surface; the two ends of the semi-annular sealing section are respectively provided with integrally formed sealing flanges, and the sealing flanges are wedge-shaped structures with gradually increasing thickness from the planar sealing section to the axial direction of the semi-annular sealing section; the inner circumferential surface of the semi-annular sealing section is also provided with at least two annular sealing grooves arranged at intervals along its axial direction. When the two sealing structures are joined together, the opposite joining surfaces fit together to achieve a planar seal on the opening and closing surfaces, the opposite sealing flanges squeeze each other to strengthen the sealing of the end face and the contact surface with the pipe, the two opposite semi-annular sealing sections are joined together to form a circular channel and wrap around the pipe, and at least two annular sealing grooves form a labyrinth curved surface seal with the outer wall of the pipe.

[0006] Furthermore, the sealing flange starts at a position 6mm-7mm away from the inner circumferential surface of the semi-annular sealing section, and the inclination of the sealing flange is 8°-12°. The highest point of the sealing flange extends 1.0mm-1.5mm beyond the mating surface of the planar sealing section.

[0007] Furthermore, the planar sealing section is configured as a recessed assembly structure, and the design compression of the mating surface is 0.8mm-1.2mm.

[0008] Furthermore, the semi-annular sealing section is configured such that when the two sealing structures are joined together, the dynamic compression between its inner circumferential surface and the outer wall surface of the pipe is 1.3mm-1.7mm.

[0009] Furthermore, the number of annular sealing grooves is two, and the compression between the bottom of the two annular sealing grooves and the outer wall of the pipe is 0.6mm-0.9mm.

[0010] Furthermore, the sealing structure is integrally molded from silicone rubber with long-lasting cushioning properties.

[0011] The present invention also constructs an online diagnostic device for the sealing performance of pipeline joints, including a device body and a testing platform (8). The device body includes a first housing, a second housing and two sealing structures as described above. One end of the first housing and the second housing are hinged together, and the other end of the first housing and the second housing are detachably locked and fixed. The sealing structures are fixedly installed on the opposite end faces of the first housing and the second housing, respectively. After the first housing and the second housing are closed together, they cover the pipe, and a sealed space is formed between the first housing, the second housing and the outer wall of the pipe. The first housing or the second housing is provided with a vent hole that penetrates the side wall, and the vent hole is connected to a vent connector; The testing platform is connected to the ventilation connector for ventilation and non-destructive testing. Furthermore, the detection platform includes a housing and a power source, pressure gauge, safety valve, shut-off valve, and gas diversion module integrated inside the housing; the power source is connected to the vent connector via an air pipe and provides a gas source, the pressure gauge is connected to the air pipe to monitor the air pressure, and the safety valve is connected to the air pipe and is set to automatically release pressure when the air pressure exceeds a preset threshold.

[0012] This invention also provides an online diagnostic method for the sealing performance of pipeline joints, comprising the following steps: S1. Provide an online diagnostic device for the sealing performance of pipeline joints as described above; S2. After closing the first housing and the second housing together, cover the outside of the installed pipeline joint, so that the sealing structure wraps around the pipes at both ends of the pipeline joint and forms a sealed space between the first housing, the second housing and the outer wall of the pipe; S3. Connect the air source through the vent connector and fill the sealed space with pressurized gas through the vent hole; monitor the air pressure change in the sealed space to determine the sealing performance of the pipeline connector.

[0013] Furthermore, in step S3, the power source integrated in the detection platform automatically performs the step of filling pressurized gas; when the pressure gauge detects that the gas pressure reaches the preset threshold, the control module automatically stops the gas supply and maintains the pressure holding state, and judges the sealing performance of the pipeline joint by monitoring the gas pressure change during the pressure holding period.

[0014] By implementing this invention, the following beneficial effects are achieved: The pipeline joint sealing performance online diagnostic sealing structure of this invention utilizes an integrally formed closed frame structure of a planar sealing section and a semi-annular sealing section. This creates a continuous, uninterrupted unified seal across the opening and closing plane, the curved surface of the joint pipe, and the transition area between the two. This eliminates multi-layer overlap and interface misalignment, achieving a seamless overall seal. By incorporating integrally formed wedge-shaped sealing flanges at both ends of the semi-annular sealing section, these flanges compress against each other during assembly, adaptively filling assembly gaps, compensating for assembly deviations and structural deformations, and providing gapless sealing and reinforcement in the transition area between the planar and curved surfaces. At least two annular sealing grooves on the inner circumference of the semi-annular sealing section form a labyrinthine curved surface seal with the outer wall of the pipe after assembly, providing a tortuous leakage path and forming multiple leak-proof lines, achieving flexible fit and long-term leak prevention in the curved area. The interlocking surfaces of the planar sealing section achieve end-face sealing, which, in conjunction with the reinforced sealing of the sealing flanges and the labyrinthine seal, achieves a seamless, uninterrupted, and blind-zone-free seal across the entire area from the planar to the curved surface.

[0015] The pipeline joint sealing performance online diagnostic device of the present invention is formed by hinged connection of one end of the first housing and the second housing at the other end, and detachable locking and fixing. After being closed together, it covers the pipeline and forms a sealed space with the sealing structure. That is, the main body of the device can be completely sealed and wrapped from the outside of the joint. With the testing platform, it can realize non-destructive testing of the installed joint without intruding into the pipeline.

[0016] The pipeline joint sealing performance online diagnostic method of the present invention provides an online diagnostic device after the joint is installed, and closes the first and second housings to cover the outside of the pipeline joint to form a sealed space. Pressurized gas is filled from the outside and the gas pressure change is monitored, which enables the joint sealing performance to be verified after installation, and makes the sealing effect change from invisible to quantifiable test. Attached Figure Description

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings: Figure 1 This is a schematic diagram of the sealing structure according to Embodiment 1 of the present invention; Figure 2 yes Figure 1 Top view of the sealing structure in the middle; Figure 3 yes Figure 1 Side view of the sealing structure in the middle; Figure 4 yes Figure 2 CC cross-sectional view of the sealing structure in the middle; Figure 5 This is a schematic diagram of the online diagnostic device according to Embodiment 2 of the present invention; Figure 6 yes Figure 5 A magnified schematic diagram of the online diagnostic device, where the detection platform is not shown; Figure 7 yes Figure 6 Front view of the online diagnostic device; Figure 8 yes Figure 6 One of the installation diagrams of the online diagnostic device covering the pipeline joint, in which the first and second housings are not joined together; Figure 9 yes Figure 8 The second schematic diagram shows the installation of the online diagnostic device covering the pipeline joint, in which the first and second housings are joined and fixed together. Figure 10 yes Figure 6 A schematic diagram of the structure of the first shell in the middle; Figure 11 yes Figure 6 A schematic diagram of the structure of the second shell in the middle; Figure 12 yes Figure 5 A three-dimensional structural diagram of the detection platform is shown, in which the box body is not shown; Figure 13 yes Figure 12 A top view of the detection platform in the middle; Figure 14 yes Figure 12 Front view of the detection platform in the middle; Figure 15 yes Figure 12 The left view of the detection platform in the image. Detailed Implementation

[0018] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0019] It should be noted that the flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily have to be performed in the described order. For example, some operations / steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0020] In the description of the invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the 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, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of the invention, unless otherwise stated, "a plurality of" means two or more.

[0021] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or a chemical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0022] Example 1: See Figures 1 to 12 This embodiment discloses a sealing structure 1 for online diagnosis of the sealing performance of a pipeline joint. This sealing structure 1 is used for sealing the opening and closing surfaces of two assembled parts and for sealing the outer wall contact surface of the pipe 91 penetrating the two assembled parts.

[0023] like Figure 1 and Figure 2 As shown, the sealing structure 1 specifically includes two opposing planar sealing sections 11 and two opposing semi-annular sealing sections 12. The planar sealing sections 11 are located on opposite sides, and the semi-annular sealing sections 12 are located at both ends. That is, one planar sealing section 11 connects to one semi-annular sealing section 12, then connects to another planar sealing section 11, then connects to another semi-annular sealing section 12, and so on, alternating in a circumferential manner, ultimately forming a closed and integrally molded frame structure. This frame structure has no splicing gaps.

[0024] Each planar sealing segment 11 has a mating surface 111. When two sealing structures 1 are mated together, the two mating surfaces 111 fit tightly together, thus achieving a planar seal at the opening of the assembled body. In this embodiment, the planar sealing segment 11 is configured as a recessed assembly structure, that is, the sealing structure 1 is installed in the recess 4 of the housing, so that the mating surface 111 is slightly recessed relative to the end face of the housing in the unassembled state; when the two housings are locked, the sealing structure 1 is compressed, and the two mating surfaces 111 fit tightly together under the action of elastic rebound force to achieve end face seal. This recessed assembly structure can limit and protect the sealing structure, prevent displacement or shearing during the assembly process, and ensure a stable pre-compression amount each time it is assembled, thereby improving the sealing reliability. The designed compression amount of the mating surface 111 is 0.8mm-1.2mm, for example, it can be 0.8mm, 1.0mm or 1.2mm, preferably 1.0mm. The compression amount refers to the thickness of the mating surface 111 compressed when the surfaces are joined. This design ensures a uniform and rigid fit between the sealing surfaces, achieving a stable pressure seal. Testing showed that when the compression amount is less than 0.8mm, the contact pressure between the mating surfaces is insufficient to counteract the thrust of the internal air pressure, easily leading to gap leakage during pressure fluctuations. When the compression amount is greater than 1.2mm, the locking force increases significantly, and the sealing material is prone to permanent plastic deformation, affecting the reliability of repeated use. Controlling the compression amount within the range of 0.8mm-1.2mm ensures the basic sealing pressure while keeping the sealing surface in the elastic deformation zone, resulting in no significant attenuation of sealing performance after 500 opening and closing cycles.

[0025] like Figure 3 and Figure 4As shown, each semi-annular sealing section 12 is semi-circular in shape, with its inner circumferential surface used to contact the outer wall of the pipe 91. Each end of the semi-annular sealing section 12 has an integrally formed sealing flange 121. The dimensions of the two semi-annular sealing sections 12 can be the same or different, depending on the size of the pipe 91 to be covered. Figure 2 As shown, this is one design of the semi-annular sealing section 12, where the diameter of the left semi-annular sealing section 12 is slightly smaller than that of the right semi-annular sealing section 12. Figure 3 As shown, the sealing flange 121 is a wedge-shaped structure with gradually increasing thickness from the planar sealing section 11 towards the semi-annular sealing section 12 along the axial direction. The sealing flange 121 starts at a position 6mm-7mm away from the inner circumferential surface of the semi-annular sealing section 12, for example, 6mm, 6.5mm, or 7mm, preferably 6.81mm; its inclination is 8°-12°, for example, 8°, 10°, or 12°, preferably 10°. The highest point of the sealing flange 121 exceeds the joint surface 111 of the planar sealing section 11 by a height ranging from 1.0mm to 1.5mm, for example, 1.0mm, 1.2mm, or 1.5mm, preferably 1.2mm. The above three sets of parameters were obtained through synergistic optimization using finite element analysis and leakage rate experiments. When the two sealing structures 1 are joined, the opposing sealing flanges 121 will press against each other to strengthen the sealing of the end faces and the contact surface with the pipe 91. Due to the guiding and filling effect of the wedge structure, the sealing flange 121 can adaptively fill the gap caused by assembly tolerances or deformation, and reinforce and seal the high-risk leakage area at the transition between the plane and the curved surface, thereby enhancing the end face sealing effect.

[0026] Specifically, the starting position of the flange is set to 6mm-7mm from the inner circumference. If the starting distance is less than 6mm, the flange root is too close to the outer wall of the pipe, which can easily cause interference during splicing, resulting in the flange failing to fit properly or even causing permanent deformation. If the starting distance is greater than 7mm, the effective compression stroke of the flange is shortened, and the reinforcing effect of the end face seal decreases. Controlling the starting distance to 6mm-7mm can obtain sufficient elastic deformation stroke while avoiding interference, ensuring that the flange is in the optimal stress state during splicing.

[0027] An inclination angle of 8°-12° ensures that the flange makes gradual contact from tip to root during compression. If the inclination angle is less than 8°, the flange is approximately of uniform thickness, resulting in dispersed contact pressure and a sealing pressure below 1MPa. If the inclination angle is greater than 12°, the flange tip is too thin, making it prone to curling or breakage after repeated use. An inclination angle of 8°-12° combined with an excess of 1.0mm-1.5mm can generate an effective compression of 0.6mm-0.9mm under normal locking force. Helium gas chromatography leak detection shows that the leakage rate of this sealing structure is significantly lower than that of conventional single-channel sealing groove structures, greatly improving the sealing reliability of online pipe joint inspections. Furthermore, the leakage rate shows no significant increase after 500 opening and closing cycles.

[0028] Understandably, the height of the highest point of the sealing flange 121 exceeding the mating surface 111 of the planar sealing section 11 is between 1.0mm and 1.5mm, and the designed compression of the mating surface 111 is between 0.8mm and 1.2mm. This means that the distance between the highest point of the sealing flange 121 and the pipe 91 is between 1.8mm and 2.7mm, preferably 2.2mm. At this distance, when the sealing flange 121 is mated, it first contacts the opposite sealing flange 121 and generates progressive compression, while its root still retains sufficient space for elastic deformation, thereby achieving precise filling and compensation of the leakage gap in the transition superposition area.

[0029] like Figure 4 As shown, the inner circumferential surface of the semi-annular sealing section 12 is also provided with at least two annular sealing grooves 122 arranged at intervals along its axial direction. In this embodiment, the number of annular sealing grooves 122 is preferably two. When the two sealing structures 1 are assembled, the two opposing semi-annular sealing sections 12 are assembled into a circular channel and wrap around the pipe 91, and are tightly attached to the outer wall of the pipe 91. At this time, a labyrinth seal is formed between the at least two annular sealing grooves 122 and the outer wall of the pipe 91. Specifically, the number of annular sealing grooves 122 is two, and the compression between the bottom of the two annular sealing grooves 122 and the outer wall of the pipe 91 is 0.6mm-0.9mm, for example, it can be 0.6mm, 0.75mm or 0.9mm, preferably 0.75mm. The labyrinth curved surface seal refers to increasing the resistance to gas leakage through the tortuous gaps, forming multiple leak-proof defense lines, and realizing flexible curved surface fitting and high-pressure long-term leak prevention. If the compression is less than 0.6 mm, the gap between the bottom of the groove and the pipe is too large, resulting in low flow resistance of the leaking medium and an insignificant labyrinth effect. If the compression is greater than 0.9 mm, the rubber material is over-compressed, which not only increases assembly resistance but may also cause local tearing of the groove bottom. A compression of 0.6 mm to 0.9 mm creates a narrow, tortuous gap between each sealing groove and the outer wall of the pipe. Two grooves connected in series form a two-stage throttling and pressure reduction, resulting in a much lower overall leakage rate compared to a single sealing groove structure.

[0030] In some embodiments, the sealing structure 1 is integrally molded from silicone rubber with long-lasting cushioning properties. Silicone rubber material possesses excellent elasticity, fatigue resistance, and cushioning performance, which can significantly reduce fatigue wear of the seal during long-term operation and extend its service life. As an alternative, depending on different operating conditions, other rubber materials with long-lasting cushioning properties, such as hydrogenated nitrile rubber, fluororubber, or EPDM rubber, can also be used to achieve similar cushioning and sealing effects.

[0031] Understandably, the sealing structure 1 of the present invention is particularly suitable for the nuclear power plant field. The design compression amount of the mating surface 111, the starting position and length of the sealing flange 121, the highest point and inclination of the sealing flange 121, etc., as defined above are all designed according to the sealing requirements of the nuclear power plant field. If applied to other non-nuclear power fields, the relevant parameters can be adapted to the sealing requirements of the corresponding field.

[0032] The sealing structure 1 of the present invention can also be used for sealing the opening and closing surfaces of three or more assemblies and for sealing the outer wall contact surfaces of the pipe 91 penetrating each assembly. The sealing structure 1 described above is provided between the opening and closing surfaces of every two assemblies. The sealing structure 1 is modified adaptively according to the dimensions of the opening and closing surfaces of the assemblies. For example, when there are three assemblies, the semi-annular sealing section 12 is designed as a 1 / 3-ring sealing section; when there are four assemblies, the semi-annular sealing section 12 is designed as a 1 / 4-ring sealing section, and so on. Other structures are similar.

[0033] The sealing structure 1 of the present invention has the following technical effects: First, the integrated structure eliminates the defects of split-part splicing. The sealing structure 1 adopts an integrated frame structure formed by alternating connection of the planar sealing section 11 and the semi-ring sealing section 12, so that the central opening plane, the curved surface of the joint pipe 91 and the transition area between the two form a continuous and unbroken unified seal, which completely eliminates the inherent leakage hazards such as multi-layer superposition, misalignment of the interface and exposed split cut at the joint of traditional planar gaskets and split seals.

[0034] Second, adaptive reinforcement overcomes the sealing challenge in the transition zone. The two ends of the semi-annular sealing section 12 are equipped with wedge-shaped sealing flanges 121, which squeeze against each other during assembly. This adaptively fills the assembly gap, compensates for deviations and deformations, and achieves gapless sealing reinforcement in the high-risk leakage area of ​​the transition between the planar and curved surfaces.

[0035] Third, zoned collaborative sealing achieves a complete seal without blind spots. The mating surface 111 of the planar sealing section 11 achieves basic end face sealing; at least two annular sealing grooves 122 on the inner circumference of the semi-annular sealing section 12 form a labyrinth curved surface seal with the outer wall of the pipe 91, providing multiple leak-proof defenses; each sealing zone is synchronously linked and seamlessly connected, with no weak sealing points throughout the entire process.

[0036] Example 2: like Figures 5 to 11 As shown, this embodiment discloses an online diagnostic device for the sealing performance of pipeline joints, used for external non-destructive leak detection of installed pipeline joints 9. Figure 5 and Figure 6As shown, the online diagnostic device includes a main body and a testing platform 8. The main body includes a first housing 2, a second housing 3, and two sealing structures 1 as described in Embodiment 1. In this embodiment, the first housing 2 and the second housing 3 are two assembled bodies as referred to in Embodiment 1, and the end face shapes of the first housing 2 and the second housing 3 respectively match the sealing structure 1.

[0037] like Figure 7 and Figure 8 As shown, one end of the first housing 2 and the second housing 3 are hinged, for example, by a hinge 5, allowing them to be carried as a single unit and opened and closed by rotation. The other end of the first housing 2 and the second housing 3 is detachably locked, for example, by bolts 6 passing through the first housing 2 and the second housing 3 and tightening them. Alternatively, a locking mechanism such as a snap-fit ​​or quick-release clamp can also be used. Because of the hinge 5, the two housings will not separate during operation, facilitating quick on-site installation. The shapes of the first housing 2 and the second housing 3 are matched, and when assembled, they form a cavity surrounding the pipeline connector 9, covering the pipeline to be tested.

[0038] like Figure 10 and Figure 11 As shown, sealing structures 1 are fixedly installed on the opposite end faces of the first housing 2 and the second housing 3. Specifically, the first housing 2 and the second housing 3 are respectively provided with grooves 4, and the two sealing structures 1 are fixedly installed in these grooves 4. After the first housing 2 and the second housing 3 are closed together, they cover the pipe 91, that is, the splicing surfaces 111 of the two sealing structures 1 are in contact with each other, the sealing flanges 121 are pressed against each other, and the semi-annular sealing section 12 is spliced ​​and wrapped around the pipe 91, thereby achieving an all-round seal between the device itself and the pipe 91 and the open surface, that is, a sealed space is formed between the first housing 2, the second housing 3 and the outer wall of the pipe 91.

[0039] The first housing 2 or the second housing 3 has a vent hole penetrating its side wall, and the vent hole is connected to a vent connector 7. The testing platform 8 is connected to the vent connector 7 for ventilation and non-destructive testing. Figure 10 As shown, in this embodiment, a vent is provided on the first housing 2, and the vent connector 7 is fixedly connected to the first housing 2. The vent is obstructed and is not shown in the figure.

[0040] like Figure 5 and Figures 12 to 15As shown, the detection platform 8 is an integrated portable device, comprising a housing 81 and integrated within the housing 81 a power source 82, a pressure gauge 83, a safety valve 84, a shut-off valve 85, and a gas diversion module 86. The power source 82 is connected to the air inlet 7 via an air pipe to supply pressurized gas to the confined space. The power source 82 can be an air pump, and the housing 81 also has an air pipe connector for connecting to the air pump to provide air intake. The power source 82 contains a rechargeable battery as its power source. The pressure gauge 83 is connected to the air pipe to monitor the air pressure in real time. The pressure gauge 83 can be a digital pressure gauge with a built-in battery. The safety valve 84 acts as a mechanical overpressure protection device, automatically releasing pressure when the air pressure exceeds a set value. The shut-off valve 85 is used to quickly cut off the gas supply manually or in emergencies. The gas diversion module 86 can be used to regulate or divert gas. The gas splitting module 86 may include a two-position four-hole splitter and a detection gas tube outlet. The two-position four-hole splitter is connected to the detection gas tube outlet and the air pump respectively. The detection gas tube outlet and the air inlet 7 are detachably connected through the air tube.

[0041] Optionally, to achieve integrated installation of components, the testing platform 8 also includes a mounting panel 87, a safety valve 84 mounting bracket, an air pump mounting bracket 89, a first storage box 810, a second storage box 811, and a shut-off valve 85 mounting bracket. The mounting panel 87 is placed inside the housing 81 and secured with a snap-fit ​​mechanism. The safety valve 84 mounting bracket, air pump mounting bracket 89, first storage box 810, second storage box 811, and shut-off valve 85 mounting bracket are respectively and spaced apart on the mounting panel 87, each with a space to accommodate the corresponding components. Specifically, the safety valve 84 is placed inside the safety valve 84 mounting bracket, the power source 82 is placed on the air pump mounting bracket 89, the pressure gauge 83 is placed in the first storage box 810, and the shut-off valve 85 is placed inside the shut-off valve 85 mounting bracket, with the corresponding operating or display end exposed above the mounting panel 87 for operation. The second storage box 811 is used to place the main body of the device when the online diagnostic device is not in use, facilitating overall device storage. The panel can also be equipped with an air pump charging port 813, which can be used to charge the air pump's rechargeable battery when convenient.

[0042] The working principle of the online diagnostic device for pipeline joint sealing performance in this embodiment is as follows: After the first housing 2 and the second housing 3 are assembled, installed, and locked, the operator starts the power source 82 of the testing platform 8 to inflate the sealed space. During the inflation process, the operator observes the reading of the pressure gauge 83. When the pressure gauge 83 shows that the air pressure has reached the preset testing pressure value, the operator manually shuts off the power source 82 or closes the shut-off valve 85 to enter the pressure holding state. During the set pressure holding time, the operator continuously observes the change in the reading of the pressure gauge 83. If the pressure drop is less than the preset allowable value, the pipeline joint sealing performance is deemed qualified; otherwise, leakage is deemed to exist. During the inflation process, if the air pressure exceeds the set threshold of the safety valve 84 due to operational errors or other reasons, the safety valve 84 will automatically open to release pressure, preventing excessive air pressure in the sealed space from damaging the pipeline or joint, thus providing mechanical overpressure protection.

[0043] The online diagnostic device for pipeline joint sealing performance of the present invention has the following technical advantages: First, the external wrapping non-destructive testing method does not intrude into the interior of the pipe 91 and can test the pipe joint 9 without disassembling the upstream and downstream pipes 91. The first housing 2 and the second housing 3 are hinged together, and the other end can be detached and locked. After closing with each other, they cover the pipe 91 and together with the sealing structure 1, they form a sealed space. This allows for overall wrapping and pressurization testing of the joint from the outside, avoiding the limitations of traditional internal or upstream and downstream pressurization and the damage to the pipe 91 itself.

[0044] Secondly, the integrated portable pressurization system offers strong on-site adaptability. The testing platform 8 integrates the power source 82, pressure gauge 83, safety valve 84, shut-off valve 85, gas diversion module 86, and control module inside the housing 81, forming a portable pressurization testing unit. Furthermore, the power source 82 has a built-in rechargeable battery, eliminating the need for an external power or gas source, thus improving on-site testing convenience and significantly enhancing the flexibility and efficiency of testing.

[0045] Third, multiple safety protections ensure reliable testing. The control module automatically suspends the power source 82 and stops the gas supply in case of overpressure. The safety valve 84 and the shut-off valve 85 provide dual mechanical and electrical overpressure protection to ensure that the testing process is safe and controllable.

[0046] Fourth, it has the function of temporary pressurized sealing of leaking pipelines. When a leak occurs in pipeline joint 9 or pipe 91, the system does not need to be shut down. This device can be directly wrapped around the leaking part, and the vent joint 7 can be replaced with a sealing plug to achieve temporary external pressurized sealing, effectively controlling the leakage of media and providing a valuable window of opportunity for system repair or planned shutdown.

[0047] Example 3: This embodiment provides an online diagnostic method for the sealing performance of pipeline joints, using the sealing structure 1 of Embodiment 1 and the online diagnostic device for the sealing performance of pipeline joints of Embodiment 2, including the following steps: S1. Provide an online diagnostic device for the sealing performance of pipeline joints as in Embodiment 2, i.e., prepare a device body with a testing platform 8, the device body including a first housing 2, a second housing 3 and an installed sealing structure 1.

[0048] S2. After closing the first housing 2 and the second housing 3 together, they cover the outside of the installed pipeline joint 9, so that the sealing structure 1 wraps around the pipes 91 at both ends of the pipeline joint 9, and forms a sealed space between the first housing 2, the second housing 3 and the outer wall of the pipe 91.

[0049] Specifically, such as Figure 8 and Figure 9 The first housing 2 and the second housing 3 can be locked and fixed by bolts 6. During this process, the two sealing structures 1 are compressed, their mating surfaces 111 fit together, the sealing flanges 121 are squeezed together, and the semi-annular sealing section 12 wraps around the pipes 91 at both ends of the pipeline joint 9, thereby forming a sealed space isolated from the outside world between the inner walls of the first housing 2 and the second housing 3 and the outer wall of the pipe 91.

[0050] S3. Start the testing platform 8 and connect the air source through the vent connector 7 to allow pressurized gas to fill the sealed space through the vent. After the preset pressure is reached, stop the gas supply and maintain the pressure. Continuously monitor the pressure changes within the sealed space. Determine the sealing performance of the pipeline connector 9 based on the pressure changes during the pressure maintenance period.

[0051] In a preferred embodiment, step S3 is automatically completed by the detection platform 8. Specifically, the control module controls the power source 82 to automatically inflate the air. When the pressure gauge 83 detects that the air pressure has reached a preset threshold, the control module automatically stops the air supply and maintains a pressure-holding state. By monitoring the air pressure changes during the pressure-holding period, the pressure drop is automatically calculated and compared with the preset threshold, and finally the judgment result is output.

[0052] The online diagnostic method for pipeline joint sealing performance of the present invention has the following technical advantages: First, it enables the verification of sealing performance after installation. For the first time, a pressure verification approach is proposed: after the joint is installed, a sealed air chamber is formed by external wrapping, pressurization is performed, and pressure changes are monitored. This transforms the joint's sealing performance from a process-controlled process to a quantifiable and verifiable objective test, filling a technological gap in this field.

[0053] Secondly, automatic inflation and pressure holding with clear judgment criteria. The power source 82 automatically performs inflation, and after reaching the preset threshold, it automatically stops supplying air and maintains the pressure holding state. The sealing performance is judged by monitoring the air pressure change during the pressure holding period. The operation is simple, the results are objective, and human error is reduced.

[0054] Third, it is a non-destructive, online, and rapid inspection that does not affect system operation. The inspection process can be completed before the pipeline system is fully restored, without the need to disassemble joints or interrupt subsequent work, significantly improving the timeliness and reliability of construction quality control.

[0055] It is understood that the above embodiments only illustrate preferred embodiments of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that for those skilled in the art, the above embodiments or technical features can be freely combined, and several modifications and improvements can be made without departing from the concept of the present invention. These all fall within the protection scope of the present invention. That is, the embodiments described "in some embodiments" can be freely combined with any of the embodiments above and below. Therefore, all equivalent transformations and modifications made within the scope of the claims of the present invention should fall within the scope of the claims of the present invention.

Claims

1. A pipeline joint sealing structure (1) for online diagnostic testing of sealing performance, used for sealing the opening and closing surfaces of two assembled bodies and sealing the outer wall contact surface of the pipe (91) penetrating the two assembled bodies, characterized in that, It includes two opposing planar sealing sections (11) and two opposing semi-annular sealing sections (12); the planar sealing sections (11) are located on opposite sides, and the semi-annular sealing sections (12) are located at both ends, forming a closed and integral frame structure. The planar sealing section (11) has a mating surface (111); the two ends of the semi-annular sealing section (12) are respectively provided with integrally formed sealing flanges (121), and the sealing flanges (121) are wedge-shaped structures with gradually increasing thickness from the planar sealing section (11) to the axial direction of the semi-annular sealing section (12); the inner circumferential surface of the semi-annular sealing section (12) is also provided with at least two annular sealing grooves (122) arranged at intervals along its axial direction. When the two sealing structures (1) are assembled, the opposing assembly surfaces (111) fit together to achieve a planar seal on the opening and closing surfaces, the opposing sealing flanges (121) press against each other to strengthen the sealing of the end face and the contact surface with the pipe (91), the two opposing semi-annular sealing sections (12) are assembled into a circular channel and wrap around the pipe (91), and at least two annular sealing grooves (122) form a labyrinth curved surface seal with the outer wall of the pipe (91).

2. The online diagnostic sealing structure (1) for pipeline joint sealing performance according to claim 1, characterized in that, The sealing flange (121) starts at a position 6mm-7mm away from the inner circumferential surface of the semi-annular sealing section (12), and the inclination of the sealing flange (121) is 8°-12°. The highest point of the sealing flange (121) extends 1.0mm-1.5mm beyond the splicing surface (111) of the planar sealing section (11).

3. The online diagnostic sealing structure (1) for pipeline joint sealing performance according to claim 1, characterized in that, The planar sealing section (11) is configured as a recessed assembly structure, and the design compression of the mating surface (111) is 0.8mm-1.2mm.

4. The online diagnostic sealing structure (1) for pipeline joint sealing performance according to claim 1, characterized in that, The semi-annular sealing section (12) is configured such that when the two sealing structures (1) are joined together, the dynamic compression between its inner circumferential surface and the outer wall of the pipe (91) is 1.3 mm to 1.7 mm.

5. The online diagnostic sealing structure (1) for pipeline joint sealing performance according to claim 1, characterized in that, The number of the annular sealing grooves (122) is two, and the compression between the bottom of the two annular sealing grooves (122) and the outer wall of the pipe (91) is 0.6mm-0.9mm.

6. The online diagnostic sealing structure (1) for pipeline joint sealing performance according to claim 1, characterized in that, The sealing structure (1) is integrally molded from silicone rubber with long-lasting cushioning properties.

7. An online diagnostic device for the sealing performance of pipeline joints, characterized in that, The device includes a main body and a testing platform (8). The main body includes a first housing (2), a second housing (3), and two sealing structures (1) as described in any one of claims 1-6. One end of the first housing (2) and the second housing (3) are hinged together, and the other ends of the first housing (2) and the second housing (3) are detachably locked and fixed. The sealing structures (1) are fixedly installed on the opposite end faces of the first housing (2) and the second housing (3). After the first shell (2) and the second shell (3) are closed together, they cover the pipe (91), and a sealed space is formed between the first shell (2), the second shell (3) and the outer wall of the pipe (91); The first housing (2) or the second housing (3) is provided with a vent hole that penetrates the side wall, and the vent hole is connected to the vent connector (7); The testing platform (8) is connected to the ventilation connector (7) for ventilation and non-destructive testing.

8. The online diagnostic device for pipeline joint sealing performance according to claim 7, characterized in that, The detection platform (8) includes a housing (81) and a power source (82), a pressure gauge (83), a safety valve (84), a shut-off valve (85), and a gas diversion module (86) integrated inside the housing (81). The power source (82) is connected to the air connector (7) through an air pipe and provides an air source. The pressure gauge (83) is connected to the air pipe to monitor the air pressure. The safety valve (84) is connected to the air pipe and is set to automatically release pressure when the air pressure exceeds a preset threshold.

9. A method for online diagnosis of the sealing performance of pipeline joints, characterized in that, Includes the following steps: S1. Provide an online diagnostic device for the sealing performance of pipeline joints as described in claim 7 or 8; S2. After closing the first housing (2) and the second housing (3) together, they cover the outside of the installed pipeline joint (9), so that the sealing structure (1) wraps the pipes (91) at both ends of the pipeline joint (9) and forms a sealed space between the first housing (2), the second housing (3) and the outer wall of the pipe (91); S3. Connect the air source through the vent connector (7) and fill the sealed space with pressurized gas through the vent hole; monitor the air pressure change in the sealed space to determine the sealing performance of the pipeline connector (9).

10. The online diagnostic method for pipeline joint sealing performance according to claim 9, characterized in that, In step S3, the power source (82) integrated in the detection platform (8) automatically performs the step of filling pressurized gas; when the pressure gauge (83) detects that the gas pressure reaches the preset threshold, the control module automatically stops the gas supply and maintains the pressure holding state, and judges the sealing performance of the pipeline joint (9) by monitoring the gas pressure change during the pressure holding period.

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