Gas storage cavern lining crack repairing device and system and gas storage cavern

Abstract

The invention relates to the technical field of underground gas storage caverns, in particular to a crack repairing device and system for a gas storage cavern lining and a gas storage cavern. The crack repairing device comprises a grouting main pipe and a plurality of grouting ring pipes which are communicated, the grouting main pipe is arranged in the axial direction of the cavern, and the grouting ring pipes extend in the annular direction of the cavern and are buried in the lining; the grouting ring pipes are arranged at intervals in the axial direction of the cavern, a plurality of grouting holes are formed in the grouting ring pipes, and grout can enter the grouting ring pipes from the grouting main pipes and flow out along the grouting holes. When the cavern is subjected to internal pressure and the lining cracks, grout injected into the grouting main pipe can enter the grouting ring pipe and permeate into the cracks of the lining from the grouting holes in the grouting ring pipe, and the lining cracks are repaired. By the adoption of the crack repairing device, the lining of the gas storage cavern can be reinforced in time, then a sealing layer is protected, the leakage rate is reduced, the frequency of pausing cavern operation overhaul is reduced, the normal operation efficiency of the cavern can be guaranteed, and the operation and overhaul cost of the cavern is reduced.

Description

Technical Field

[0001] This invention relates to the field of underground gas storage cavern technology, and particularly to a crack repair device, system, and gas storage cavern lining. Background Technology

[0002] Compressed air energy storage power stations store energy and regulate peak demand by continuously circulating and releasing air in a storage cavern, which can reach pressures of up to 10-15 MPa. Under high internal pressure, the cavern lining is torn apart, and the storage cavern needs to operate with cracks. This not only weakens the overall mechanical properties of the cavern structure, but more importantly, if the sealing layer leaks, the high-pressure gas will escape directly through the lining cracks. Excessive leakage rate will directly affect the economic benefits of the storage cavern.

[0003] Lining cracks can also have an adverse effect on the sealing layer. If a flexible seal is used, the sealing structure may be sheared or squeezed out at the cracks in the concrete lining, resulting in seal damage. If a steel lining is used, groundwater in the surrounding rock will form seepage channels through the lining cracks, exerting external water pressure on the steel lining and affecting its stability. In severe cases, this can lead to the collapse and failure of the steel lining.

[0004] According to current design concepts for artificial gas storage caverns, cracks in the cavern lining under high internal pressure (10-15 MPa) are inevitable. The cavern must operate with these cracks throughout its length, which not only weakens the overall mechanical and sealing performance of the cavern structure but also creates numerous difficulties for lining maintenance during actual operation. Currently, lining cracks in gas storage caverns can only be repaired manually. For lining maintenance, all personnel, materials, and equipment must enter and exit through a plug structure at the cavern end. The limited space inside the plug severely restricts the access and operation of large maintenance equipment. Manual maintenance requires frequent interruptions of cavern operation and depressurization, significantly reducing cavern operating efficiency, thereby decreasing the operational availability and dispatch flexibility of the compressed air energy storage power station and harming its economic benefits. Summary of the Invention

[0005] The purpose of this invention is to overcome the technical problems of existing gas storage cavern linings being prone to cracking under alternating internal pressure, resulting in structural performance degradation, sealing failure, and difficulties in traditional maintenance methods, which affect operational efficiency. The invention provides a crack repair device, system, and gas storage cavern lining.

[0006] In a first aspect, the present invention provides a crack repair device for the lining of a gas storage cavern, comprising a grouting main pipe and a plurality of grouting ring pipes connected in communication. The grouting main pipe is arranged along the axial direction of the cavern, and the grouting ring pipes extend circumferentially along the cavern and are embedded in the lining. The plurality of grouting ring pipes are arranged at intervals along the axial direction of the cavern, and the grouting ring pipes are provided with a plurality of grouting holes, through which grout can enter the grouting ring pipes from the grouting main pipe and flow out along the grouting holes.

[0007] This invention, by installing grouting pipes in the cavern, allows for grouting repair of cracks in the lining caused by internal pressure. This replaces the traditional manual inspection method that requires maintenance personnel to enter the cavern, reducing the frequency of interruptions in cavern operation for personnel and equipment maintenance. Specifically, the crack repair device may include a main grouting pipe arranged along the axial direction of the cavern and multiple grouting ring pipes extending circumferentially along the cavern and arranged axially. Grout is injected into the main grouting pipe and maintained at a certain pressure. When the lining cracks due to internal pressure, the grout can enter the grouting ring pipes along the main grouting pipe and seep into the cracks in the lining through the grouting holes on the ring pipes, ultimately repairing the lining cracks. Using the crack repair device of this invention avoids the need to stop cavern operation during manual maintenance, thus ensuring the normal operating efficiency of the cavern and reducing cavern operation and maintenance costs.

[0008] Preferably, the grouting main pipe includes a first grouting main pipe and a second grouting main pipe arranged side by side, and the grouting ring pipe includes a first grouting ring pipe and a second grouting ring pipe arranged side by side. The first grouting main pipe is connected to the first grouting ring pipe through a first branch pipe, and the second grouting main pipe is connected to the second grouting ring pipe through a second branch pipe.

[0009] To prevent the grout from solidifying in the pipes and causing blockage, while simultaneously requiring the grout to solidify and repair cracks after entering the lining cracks, the crack repair device of this invention employs two independent grouting systems that are isolated from each other. Specifically, the first and second grouting main pipes are arranged in parallel and separated from each other, as are the first and second grouting ring pipes. The first grouting main pipe is only connected to the first grouting ring pipe and not to the second grouting ring pipe, and the second grouting main pipe is only connected to the second grouting ring pipe and not to the first grouting ring pipe. The grouting slurry used is a two-component slurry (such as cement-water glass two-component slurry). The main slurry A is injected into the first grouting pipe, and the slurry solidification trigger B is injected into the second grouting pipe. The A and B slurries are isolated from each other in the crack repair device, and they will not solidify in the pipes when they are not mixed. When the A and B slurries are injected into the lining cracks through the first and second grouting ring pipes respectively, the A and B slurries mix in the cracks and undergo a chemical reaction, causing the mixed slurry to solidify in the cracks, thus achieving the function of repairing the lining cracks.

[0010] For a typical cavern structure, it may include an outer lining and an inner sealing layer. The main grouting pipe can be set inside the sealing layer, i.e., inside the cavern, while the grouting ring pipe needs to be buried in the lining. In order to achieve communication between the main grouting pipe and the grouting ring pipe, a branch pipe can be connected between the main grouting pipe and the grouting ring pipe, so that the main grouting pipe and the grouting ring pipe are connected through the branch pipe. Specifically, the branch pipe can pass through the sealing layer, with one end connected to the main grouting pipe inside the sealing layer, and the other end extending into the lining and connected to the grouting ring pipe.

[0011] Preferably, both the first branch pipe and the second branch pipe are equipped with pressure balancing valves, which can be opened when subjected to the internal pressure of the cavern.

[0012] A pressure balancing valve is installed on the branch pipe, which can be opened using the internal pressure of the tunnel. Specifically, when the internal pressure of the tunnel rises and reaches a certain threshold, the pressure balancing valve can be opened to keep the branch pipe open, and the grout in the main grouting pipe can enter the grouting ring pipe along the branch pipe and seep into the cracks in the lining through the grouting holes on the grouting ring pipe to repair the cracks. When the internal pressure of the tunnel is relieved, the pressure balancing valve can be switched to the closed state to prevent the grout in the main grouting pipe from entering the grouting ring pipe and to suspend the grouting operation.

[0013] Preferably, the pressure balancing valve includes a valve body, a valve seat, a piston, a first seal, and an elastic element. The piston passes through the valve body, and the first seal is fixedly connected to the lower end of the piston and matches the first inner cavity of the valve body. The valve seat seals the lower end of the valve body, and the two ends of the elastic element are respectively connected to the first seal and the valve seat. The two sides of the valve body are respectively connected to the first branch pipe or the second branch pipe. The piston can be compressed to cause the first seal to compress the elastic element and to communicate the first branch pipe or the second branch pipe with the first inner cavity.

[0014] The opening and closing of the pressure balancing valve can be controlled by the internal pressure of the cavern. Specifically, when the internal pressure of the cavern does not exceed the elastic force of the elastic element (for example, when the cavern is under normal pressure), the piston and its lower end first seal can be fixed at the upper end of the piston stroke under the elastic force of the lower elastic element. At this time, the first seal can block the two branch pipes on both sides of the valve body, keeping the pressure balancing valve in the closed state. When pressurization is applied to the cavern, causing the pressure in the cavern to rise, and the pressure in the cavern exceeds the elastic force of the elastic element, the piston and the first seal can be fixed at the upper end of the piston stroke. Under internal pressure, it moves downwards and compresses the elastic element. When the first seal moves to the port of the branch pipe on both sides of the valve body, the branch pipe is connected to the first inner cavity of the valve body. At this time, the pressure balancing valve switches to the open state. When the cavern is depressurized, the internal pressure of the cavern drops. When the internal pressure of the cavern drops to less than the elastic force of the elastic element, the piston and the first seal can move upwards under the elastic force of the elastic element until they move to the upper end of the piston stroke, at which point they can be reset so that the first seal re-seals the port of the branch pipe, and the pressure balancing valve switches back to the closed state.

[0015] Preferably, the pressure balancing valve further includes a valve cover, which is fixedly connected to the upper end of the piston.

[0016] To allow the piston to be better subjected to the pressure inside the cavity, a valve cover can be installed at the top of the piston to increase the contact area between the piston and the high-pressure air inside the cavity, making the piston easier to compress.

[0017] Preferably, the inner wall of the valve body is provided with a boss, which divides the valve body into a second inner cavity located above and a first inner cavity located below. The piston passes through the boss, and the first seal is located in the first inner cavity.

[0018] To enhance the sealing performance of the first inner cavity of the valve body and prevent high pressure in the cavern from being transmitted to the first inner cavity, a boss is set in the valve body to divide the inner cavity of the valve body. The boss can divide the inner cavity of the valve body into an upper second inner cavity and a lower first inner cavity. The piston can pass through the boss and match the boss. The slurry in the first inner cavity cannot enter the second inner cavity along the gap between the boss and the piston, and the high pressure in the cavern cannot be transmitted to the first inner cavity.

[0019] Preferably, the piston is provided with a second seal, the second seal is located in the second inner cavity, and the second seal matches the second inner cavity.

[0020] A matching second seal is installed in the second inner cavity, which can further improve the sealing performance of the pressure balancing valve. The high pressure in the cavity above the second seal cannot be transmitted to the area below the second seal, and therefore cannot be transmitted to the first inner cavity.

[0021] Preferably, a plurality of the grouting holes are arranged in a quincunx pattern on the grouting ring pipe.

[0022] The grouting holes arranged in a quincunx pattern on the grouting ring pipe allow grout to be injected in all directions. In other words, cracks may appear at any location in the lining, but no matter where the crack appears in the lining, there are corresponding grouting holes on the grouting ring pipe to inject grout into the crack and repair it.

[0023] In a second aspect, the present invention provides a crack repair system for gas storage cavern lining, comprising a grouting pump and a crack repair device for gas storage cavern lining as described above, wherein the grouting pump is connected to the inlet end of the grouting main pipe.

[0024] In a third aspect, the present invention provides a gas storage cavity, including a lining and a sealing layer, and a crack repair device for the gas storage cavity lining as described above or a crack repair system for the gas storage cavity lining as described above, wherein the grouting main pipe is disposed inside the sealing layer.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention provides a crack repair device, system, and gas storage cavern lining. By installing grouting pipes in the cavern, grouting can be performed to repair cracks in the lining when it cracks due to internal pressure. This avoids the need to stop cavern operation for personnel and equipment access for maintenance. Specifically, the crack repair device may include a main grouting pipe arranged along the axial direction of the cavern and multiple grouting ring pipes extending circumferentially along the cavern and arranged axially. When the lining cracks due to internal pressure, the grout used for grouting can be injected into the main grouting pipe. The grout can enter the grouting ring pipes along the main grouting pipe and seep into the cracks in the lining through the grouting holes on the grouting ring pipes, ultimately repairing the lining cracks. Using the crack repair device of this invention can reduce the frequency of cavern operation interruptions for manual maintenance, thereby ensuring the normal operation efficiency of the cavern and reducing the operation and maintenance costs of the cavern.

[0026] 2. Controllable solidification of independent dual-liquid grouting: By setting up two independent grouting pipe devices, the internal isolation of the two-liquid grouts is achieved, and the grouts are mixed outside the pipes. This enables precise control over the timing and location of the solidification of the two-liquid grouts, ensuring that the grouts do not solidify inside the pipes and enabling long-term reuse of the grouting pipeline system.

[0027] 3. Precise Repair Driven by Self-Serving Pressure Balance: The entire repair process utilizes the inherent pressure rise and fall cycle during the operation of the gas storage cavern as the driving force and control signal. Without external energy or manual intervention, the system can automatically sense pressure changes, automatically trigger grouting (valve opening), and automatically terminate grouting (valve closing), achieving true self-serving real-time crack repair and greatly improving repair timeliness.

[0028] 4. Improved Structural Performance and Safety: Timely and precise grouting and curing of newly formed cracks effectively repaired the damage to the lining structure. This significantly enhanced the integrity and load-bearing capacity of the lining, thereby greatly improving the long-term stability and operational safety of the gas storage cavern support structure.

[0029] 5. Reliable sealing performance and effective control of leakage risks: After the grout solidifies, it permanently seals the lining cracks, significantly enhancing the overall sealing barrier performance of the gas storage cavern. This effectively blocks the path of gas leakage along the cracks, significantly reducing the operational leakage rate and related safety risks of the gas storage cavern.

[0030] 6. Maximizing operational continuity and economic benefits: The system can complete crack repair during normal operation of the gas storage cavern, reducing efficiency losses caused by traditional shutdowns for maintenance. It avoids the need for frequent access to the cavern by large maintenance equipment and the associated high costs and operational difficulties, thus maximizing the continuous, efficient operation and economic benefits of the compressed air energy storage power station. Attached Figure Description

[0031] Figure 1 This is a three-dimensional schematic diagram of the crack repair device for the lining of the gas storage cavity according to the present invention.

[0032] Figure 2 This is a schematic diagram of the pressure balancing valve in the closed state.

[0033] Figure 3 This is a schematic diagram showing the open state of the pressure balancing valve.

[0034] Figure 4 This is a schematic diagram showing the layout of grouting holes after the wall of the first or second grouting ring pipe is expanded.

[0035] Marked in the image: 1. First grouting main pipe, 2. Second grouting main pipe, 3. First grouting ring pipe, 4. Second grouting ring pipe, 5. First branch pipe, 6. Second branch pipe, 7. Pressure balancing valve, 71. Valve body, 711. First inner cavity, 712. Second inner cavity, 72. Valve seat, 73. Piston, 74. First sealing element, 75. Elastic element, 76. Valve cover, 77. Boss, 78. Second sealing element, 79. Sealing strip, 8. Grouting hole, 9. Lining. Detailed Implementation

[0036] The present invention will now be described in further detail with reference to specific embodiments. However, this should not be construed as limiting the scope of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0037] Unless otherwise specified, the use of terms such as "upper," "lower," "left," "right," "center," "inner," and "outer" to indicate orientation or positional relationships in the description of specific embodiments of the present invention is based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationship in which the product / equipment / device is typically placed during use. These terms are merely for the purpose of facilitating the description of the present invention or simplifying the description in specific embodiments, enabling those skilled in the art to quickly understand the solution, and do not indicate or imply that a particular device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on the present invention.

[0038] Furthermore, the use of terms such as "horizontal," "vertical," "suspended," and "parallel" does not imply that the corresponding device / component / element must be absolutely horizontal, vertical, suspended, or parallel, but rather that it can be slightly tilted or have a deviation. For example, "horizontal" merely means that its direction is more horizontal relative to "vertical," not that the structure must be completely horizontal, but that it can be slightly tilted. Alternatively, it can be simplified to mean that the corresponding device / component / element, when set in a "horizontal," "vertical," "suspended," or "parallel" direction, can have an error / deviation of ±10% relative to the corresponding direction, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, and more preferably within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its function in the present invention.

[0039] Furthermore, the use of terms such as "first," "second," and "third" in terminology is merely for distinguishing descriptions of identical or similar components and should not be interpreted as emphasizing or implying the relative importance of a particular component.

[0040] Furthermore, in the description of the embodiments of the present invention, "several", "more than", and "a number of" represent at least two. The number can be any number, such as 2, 3, 4, 5, 6, 7, 8, or 9, and can even exceed nine.

[0041] Furthermore, in the description of the technical solution of this invention, unless otherwise explicitly specified / limited / restricted, the terms "set up," "install," "connect," "link," "provided with," "laid out," and "arranged" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to common connection methods in the art, such as welding, riveting, bolting, and threaded connections. Such connections can be mechanical, electrical, or communication connections; they can be direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components.

[0042] Example 1 This embodiment provides a crack repair device for the lining of a gas storage cavern.

[0043] like Figures 1 to 4 As shown, the crack repair device for the gas storage cavern lining in this embodiment includes a connected grouting main pipe and multiple grouting ring pipes. The grouting main pipe is arranged along the axial direction of the cavern, and the grouting ring pipes extend circumferentially along the cavern and are embedded in the lining 9. The multiple grouting ring pipes are arranged at intervals along the axial direction of the cavern, and multiple grouting holes 8 are opened on the grouting ring pipes. Grout can enter the grouting ring pipes from the grouting main pipe and flow out along the grouting holes 8.

[0044] This invention allows for grouting repair of cracks in the lining 9 of a tunnel under internal pressure by installing grouting pipes within the tunnel. This avoids the need to halt tunnel operation for personnel and equipment access during maintenance. Specifically, the repair device includes a main grouting pipe arranged along the tunnel's axial direction and multiple grouting ring pipes extending circumferentially and axially along the tunnel. When the lining 9 cracks due to internal pressure, the grout used for grouting can be injected into the main grouting pipe. The grout can then enter the grouting ring pipes along the main grouting pipes and seep into the cracks in the lining 9 through the grouting holes 8 on the grouting ring pipes, ultimately repairing the cracks in the lining 9. Using this repair device reduces the frequency of tunnel operation interruptions due to manual maintenance, thereby ensuring the normal operating efficiency of the tunnel and reducing tunnel operation and maintenance costs.

[0045] In this embodiment, the grouting main pipe includes a first grouting main pipe 1 and a second grouting main pipe 2 arranged side by side, and the grouting ring pipe includes a first grouting ring pipe 3 and a second grouting ring pipe 4 arranged side by side. The first grouting main pipe 1 is connected to the first grouting ring pipe 3 through a first branch pipe 5, and the second grouting main pipe 2 is connected to the second grouting ring pipe 4 through a second branch pipe 6.

[0046] Both the first grouting main pipe 1 and the second grouting main pipe 2 can be formed by parallel double pipes made of high-strength steel round pipes. Both the first grouting main pipe 1 and the second grouting main pipe 2 are spliced ​​together from multiple sections of round pipes. The two grouting main pipes are arranged parallel to each other along the longitudinal direction of the cavern, installed at the bottom of the gas storage cavern, and welded and fixed to the sealing layer steel plate.

[0047] To prevent the grout from solidifying in the pipes and causing blockage, while simultaneously requiring the grout to solidify and repair cracks after entering the lining 9, the crack repair device of this invention employs two independent grouting systems that are isolated from each other. Specifically, the first grouting main pipe 1 and the second grouting main pipe 2 are arranged in parallel and separated from each other, as are the first grouting ring pipe 3 and the second grouting ring pipe 4. The first grouting main pipe 1 is only connected to the first grouting ring pipe 3 and not to the second grouting ring pipe 4, and the second grouting main pipe 2 is only connected to the second grouting ring pipe 4 and not to the first grouting ring pipe 3. The grout used in the crack repair device is a two-component grout (such as cement-water glass). The grouting system is a dual-liquid grouting system. Liquid A, the main grouting component, is injected into the first grouting main pipe 1, while liquid B, a grouting settling trigger, is injected into the second grouting main pipe 2. Liquids A and B are isolated from each other within the crack repair device, and will not solidify individually in the pipes when not mixed. The timing of injection of liquids A and B can be flexibly selected to ensure that the grout does not solidify inside the pipes, allowing the crack repair device to be reused. When liquids A and B are injected into the cracks in lining 9 through the first grouting ring pipe 3 and the second grouting ring pipe 4 respectively, they mix and undergo a chemical reaction in the cracks, causing the mixed grout to solidify within the cracks, thus achieving the repair function for the cracks in lining 9.

[0048] For a typical cavern structure, it may include an outer lining 9 and an inner sealing layer. The main grouting pipe can be set inside the sealing layer, i.e., inside the cavern, while the grouting ring pipe is located outside the sealing layer and needs to be embedded in the lining 9, for example, between two rows of reinforcing bars inside the lining 9. The grouting ring pipe is made of high-strength steel perforated pipe, and the pipe wall is evenly distributed with grouting holes 8 in a quincunx pattern. In order to achieve communication between the main grouting pipe and the grouting ring pipe, a branch pipe can be connected between the main grouting pipe and the grouting ring pipe, so that the main grouting pipe and the grouting ring pipe are connected through the branch pipe. Specifically, the branch pipe can pass through the sealing layer, with one end connected to the main grouting pipe inside the sealing layer, and the other end extending into the lining 9 and connected to the grouting ring pipe. The branch pipe can be made of high-strength thin steel pipe.

[0049] In this embodiment, pressure balancing valves 7 are provided on both the first branch pipe 5 and the second branch pipe 6. The pressure balancing valves 7 can be opened when subjected to the internal pressure of the cavern. Multiple pressure balancing valves 7 are arranged at intervals along the longitudinal direction of the cavern and are corresponding to the first grouting ring pipe 3 and the second grouting ring pipe 4. The arrangement of the pressure balancing valves 7 and the grouting ring pipes should avoid the joint positions of the main grouting pipe.

[0050] The pressure balancing valve 7 is a cylindrical pressure vessel. Its core principle is to use the pressure difference between the internal pressure of the gas storage cavern and the normal pressure inside the valve to drive the piston 73 to move, thus realizing the one-way valve function of spring compression. The pressure balancing valve 7 is installed on the branch pipe, and the cavern internal pressure can be used to open the valve. Specifically, when the cavern internal pressure rises and reaches a certain threshold, the pressure balancing valve 7 can be opened to keep the branch pipe open, allowing the grout in the grouting main pipe to enter the grouting ring pipe along the branch pipe and seep into the cracks in the lining 9 through the grouting holes 8 on the grouting ring pipe for crack repair. When the cavern internal pressure is released, the pressure balancing valve 7 can be switched to the closed state to prevent the grout in the grouting main pipe from entering the grouting ring pipe, thus suspending the grouting operation.

[0051] In this embodiment, the pressure balancing valve 7 includes a valve body 71, a valve seat 72, a piston 73, a first seal 74, and an elastic element 75. The piston 73 passes through the valve body 71, and the first seal 74 is fixedly connected to the lower end of the piston 73 and matches the first inner cavity 711 of the valve body 71. The valve seat 72 seals the lower end of the valve body 71, and the two ends of the elastic element 75 are respectively connected to the first seal 74 and the valve seat 72. Branch pipes are connected to both sides of the valve body 71. The piston 73 can be compressed to cause the first seal 74 to compress the elastic element 75 and to connect the branch pipe to the first inner cavity 711. The valve seat 72 is made of high-strength alloy material and is welded and fixed to the bottom of the valve body 71, forming the lower foundation of the valve. The piston 73 is a stainless steel cylinder that can move up and down within the valve body 71. The elastic element 75 is made of high-silicon chromium spring steel and is located below the first seal 74. Its bottom end is fixed to the valve seat 72, providing a pre-tightening force to close the valve. The first seal 74 can be an annular seal.

[0052] The opening and closing of the pressure balancing valve 7 can be controlled by the pressure inside the cavern. Specifically, when the pressure inside the cavern does not exceed the elastic force of the elastic element 75 (for example, when the cavern is under normal pressure), the piston 73 and its lower end first seal 74 can be fixed at the upper end of the piston 73's stroke under the elastic force of the lower elastic element 75. At this time, the first seal 74 can block the two branch pipes on both sides of the valve body 71, keeping the pressure balancing valve 7 in the closed state. When pressurizing the cavern causes the pressure inside the cavern to rise, and the pressure inside the cavern exceeds the elastic force of the elastic element 75, the piston 73 and the first seal 74 can be closed within the cavern. Under pressure, it moves downward and compresses the elastic element 75. When the first seal 74 moves to the port of the branch pipe away from both sides of the valve body 71, the branch pipe is connected to the first inner cavity 711 of the valve body 71. At this time, the pressure balancing valve 7 switches to the open state. When the cavern is depressurized, the cavern internal pressure drops. When the cavern internal pressure drops to less than the elastic force of the elastic element 75, the piston 73 and the first seal 74 can move upward under the elastic force of the elastic element 75 until they move to the upper end of the piston 73 stroke, at which point they can be reset so that the first seal 74 re-seals the port of the branch pipe, and the pressure balancing valve 7 switches back to the closed state.

[0053] Alternatively, the pressure balancing valve 7 may also include a valve cover 76, which is fixedly connected to the upper end of the piston 73.

[0054] The valve cover 76 is a high-strength stainless steel disc, which is fixedly connected to the top of the piston 73 and exposed to the environment inside the gas storage cavern. In order to make the piston 73 better subjected to the pressure inside the cavern, the valve cover 76 can be set at the upper end of the piston 73 to increase the contact area between the piston 73 and the high-pressure air inside the cavern, making the piston 73 easier to compress.

[0055] Alternatively, a boss 77 is provided on the inner wall of the valve body 71, which divides the valve body 71 into a second inner cavity 712 located above and a first inner cavity 711 located below. The piston 73 passes through the boss 77, and the first seal 74 is located in the first inner cavity 711.

[0056] The valve body 71 is a cylindrical component made of high-strength stainless steel, with two annular bosses 77 (brackets) on its inner wall, dividing the inner cavity of the valve body 71 into upper and lower parts. To enhance the sealing performance of the first inner cavity 711 of the valve body 71 and prevent high pressure in the cavern from being transmitted to the first inner cavity 711, the bosses 77 are provided in the valve body 71 to divide the inner cavity of the valve body 71 into an upper second inner cavity 712 and a lower first inner cavity 711. The piston 73 can pass through the bosses 77 and match the bosses 77. The slurry in the first inner cavity 711 cannot enter the second inner cavity 712 along the gap between the bosses 77 and the piston 73, and the high pressure in the cavern cannot be transmitted to the first inner cavity 711.

[0057] A sealing strip 79 is provided at the connection between the valve seat 72 and the valve body 71 in the first inner cavity 711. The sealing strip 79 can be a ring structure and can be made of elastic material such as rubber. The sealing strip 79 can seal the joint between the valve seat 72 and the valve body 71 to prevent the slurry in the first inner cavity 711 from seeping out and also to prevent high-pressure gas in the cavern from entering the first inner cavity 711 along the joint between the valve seat 72 and the valve body 71.

[0058] Optionally, the piston 73 is provided with a second seal 78, which is located in the second inner cavity 712 and matches the second inner cavity 712. The second seal 78 is a circular component, fixedly welded to the middle or near the middle of the piston 73, and its size is precisely matched with the inner diameter of the valve body 71 (i.e., the diameter of the second inner cavity 712). Two sealing rings are provided on the outer side of the second seal 78 to ensure good airtightness between it and the valve body 71. The second seal 78 can be a sealing plate.

[0059] The valve body 71 is divided into two spaces (first inner cavity 711 and second inner cavity 712) by an annular boss 77 (bracket). The second inner cavity 712 (high pressure cavity) located above is the active space of the second seal 78. The second seal 78 moves in the second inner cavity 712 with the piston 73 under pressure. The second inner cavity 712 is directly connected to the gas environment inside the gas storage cavern and bears the pressure inside the gas storage cavern. The first inner cavity 711 (slurry cavity) below the second seal 78 is a normal pressure space located below the annular boss 77 (bracket). This space is connected to the branch pipe interfaces on both sides through the opening in the side wall of the valve body 71. When the pressure balance valve 7 is opened, the slurry can flow in the branch pipe through the valve.

[0060] A matching second seal 78 is provided in the second inner cavity 712, which can further improve the sealing performance of the pressure balancing valve 7. The high pressure of the cavity above the second seal 78 cannot be transmitted to the bottom of the second seal 78, and thus cannot be transmitted to the first inner cavity 711.

[0061] Alternatively, multiple grouting holes 8 are arranged in a quincunx pattern on the grouting ring pipe, and multiple grouting holes 8 are opened on the main grouting pipe.

[0062] The grouting holes 8 arranged in a quincunx pattern on the grouting ring pipe can be used to inject grout in all directions. In other words, cracks may appear at any location in the lining 9, but no matter where the crack appears in the lining 9, there are corresponding grouting holes 8 on the grouting ring pipe to inject grout into the crack to repair it.

[0063] When using the device for grouting for the first time, the grouting pump should be started only when the pressure balance valve 7 is opened. At the same time as the grout enters the grouting main pipe and grouting ring pipe, the air in the pipe can be discharged from the grouting hole 8 on the grouting ring pipe and enter the crack of the lining 9, and finally enter the surrounding rock outside the lining 9 to achieve air discharge.

[0064] Working principle of pressure balancing valve 7: When the gas storage chamber is unpressurized or at low pressure, the elastic force of the elastic element 75 acts on the piston 73 through the first seal 74, keeping it in the closed position at the upper end of its stroke. At this time, the first seal 74 tightly seals and blocks the interfaces of the branch pipes on both sides leading to the slurry chamber at the lower part of the valve body 71, blocking the slurry passage, such as... Figure 2 As shown. During the pressurization phase, as the internal pressure of the gas storage cavity continuously increases, the gas pressure acts on the piston 73. When the internal pressure rises to the set opening threshold, the gas pressure acting on the second seal 78 overcomes the elastic force of the elastic element 75. Under the pressure, the piston 73 moves downward, compressing the elastic element 75 and causing the first seal 74 to move away from the pipe interfaces on both sides. The pressure balance valve 7 is then in the open state, as shown. Figure 3As shown. At this time, the grout in the grouting main pipe can flow sequentially through the grouting main pipe → the branch pipe on one side of the pressure balancing valve 7 → the first inner cavity 711 of the valve body 71 → the branch pipe on the other side of the pressure balancing valve 7 → the grouting ring pipe.

[0065] Example 2 This embodiment provides a crack repair system for the lining of a gas storage cavern.

[0066] The crack repair system for the gas storage cavern lining in this embodiment includes a grouting pump (not shown in the figure) and a crack repair device for the gas storage cavern lining as in Embodiment 1. The grouting pump is connected to the inlet end of the grouting main pipe.

[0067] The inlet end of the grouting main pipe (near the traffic chamber end) passes through the sealing head structure of the chamber and connects to the grouting pump (i.e., external booster pump) installed inside the traffic chamber; the other end of the grouting main pipe is the closed end of the gas storage chamber.

[0068] Specifically, the grouting pump may include a first grouting pump and a second grouting pump. The inlet end of the first grouting main pipe 1 is connected to the first grouting pump, and the inlet end of the second grouting main pipe 2 is connected to the second grouting pump. The first grouting pump pumps the main grout A liquid into the first grouting main pipe 1, and the second grouting pump pumps the grout coagulation trigger B liquid into the second grouting main pipe 2.

[0069] The system's workflow is as follows: Construction phase: The grouting pump is usually in the off position. The entire grouting and crack repair system (grouting main pipe, pressure balancing valve 7, branch pipe, grouting ring pipe) is installed and ready.

[0070] Operational phase: The gas storage cavern begins pressurization. The grouting pump is started, pumping repair grout A and B into the first grouting main pipe 1 and the second grouting pipe respectively, filling the main grouting pipe with grout. As the cavern pressure gradually increases, cracks appear in the cavern lining 9 under high internal pressure. When the internal pressure reaches the set opening pressure of the pressure balancing valve 7, the pressure balancing valve 7 automatically opens. Under pump pressure, grout A and B automatically flow through the opened pressure balancing valve 7, branch pipes, and grouting ring pipe, and diffuse and fuse through the grouting holes 8 on the grouting ring pipe, injecting into the newly formed cracks in the lining 9 to repair the cracks. After the repair grout A and B mix, a chemical reaction occurs, causing them to solidify and permanently seal and reinforce the cracks. When the gas storage tank enters the depressurization stage, the cavern pressure decreases. When the internal pressure of the gas storage tank drops below the set closing pressure, the spring force pushes the piston 73 assembly upwards to reset. The first seal 74 re-seals the interfaces of the branch pipes on both sides, the pressure balancing valve 7 automatically closes, cutting off the grout channel and stopping grouting. After a grouting cycle is completed, the grouting pump is connected to clean water to clean the grouting pipeline.

[0071] This completes the automatic repair process of cracks within a pressurized cycle of the gas storage cavity. The system will repeat this self-servoing process in subsequent pressurized cycles. Furthermore, the grouting can also be manually controlled by manipulating the grouting pump to initiate and deactivate the grouting process.

[0072] Example 3 This embodiment provides a gas storage cavern.

[0073] The gas storage cavern in this embodiment includes a lining 9 and a sealing layer, as well as a crack repair device for the gas storage cavern lining as in Embodiment 1 or a crack repair system for the gas storage cavern lining as in Embodiment 2. The lining 9 and the sealing layer are arranged sequentially from the outside to the inside, and the grouting main pipe is arranged inside the sealing layer. Here, the sealing layer can be a sealing steel lining.

[0074] Specifically, the grouting main pipe includes a first grouting main pipe 1 and a second grouting main pipe 2, which are arranged in parallel and are both located inside the sealing layer.

[0075] In summary, this invention provides a crack repair device, system, and gas storage cavern lining. By installing grouting pipes in the cavern, grouting can be performed to repair cracks in the lining when it cracks due to internal pressure. This reduces the frequency of interrupting cavern operation for personnel and equipment access for maintenance. Specifically, the crack repair device may include a main grouting pipe arranged along the cavern's axial direction and multiple grouting ring pipes extending circumferentially and arranged axially. When the lining cracks due to internal pressure, the grout used for grouting can be injected into the main grouting pipe. The grout can then enter the grouting ring pipes along the main grouting pipe and seep into the cracks in the lining through the grouting holes on the grouting ring pipes, ultimately repairing the lining cracks. Using the crack repair device of this invention can reduce the frequency of interrupting cavern operation during manual maintenance, thereby ensuring the normal operating efficiency of the cavern and reducing cavern operation and maintenance costs.

[0076] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A crack repair device for the lining of a gas storage cavern, characterized in that, It includes a grouting main pipe and several grouting ring pipes connected to each other. The grouting main pipe is arranged along the axial direction of the cavern. The grouting ring pipes extend circumferentially along the cavern and are embedded in the lining (9). Several grouting ring pipes are arranged at intervals along the axial direction of the cavern. Several grouting holes (8) are opened on the grouting ring pipes. Grout can enter the grouting ring pipes from the grouting main pipe and flow out along the grouting holes (8).

2. The crack repair device for the lining of a gas storage cavern according to claim 1, characterized in that, The grouting main pipe includes a first grouting main pipe (1) and a second grouting main pipe (2) arranged side by side. The grouting ring pipe includes a first grouting ring pipe (3) and a second grouting ring pipe (4) arranged side by side. The first grouting main pipe (1) is connected to the first grouting ring pipe (3) through a first branch pipe (5). The second grouting main pipe (2) is connected to the second grouting ring pipe (4) through a second branch pipe (6).

3. The crack repair device for the lining of a gas storage cavern according to claim 2, characterized in that, Both the first branch pipe (5) and the second branch pipe (6) are equipped with pressure balancing valves (7), which can be opened when subjected to the internal pressure of the cavern.

4. The crack repair device for the lining of a gas storage tunnel according to claim 3, characterized in that, The pressure balancing valve (7) includes a valve body (71), a valve seat (72), a piston (73), a first seal (74), and an elastic element (75). The piston (73) passes through the valve body (71), and the first seal (74) is fixedly connected to the lower end of the piston (73) and matches the first inner cavity (711) of the valve body (71). The valve seat (72) seals the lower end of the valve body (71). The two ends of the elastic element (75) are respectively connected to the first seal (74) and the valve seat (72). The two sides of the valve body (71) are respectively connected to the first branch pipe (5) or the second branch pipe (6). The piston (73) can be compressed to make the first seal (74) compress the elastic element (75) and make the first branch pipe (5) or the second branch pipe (6) communicate with the first inner cavity (711).

5. The crack repair device for the lining of a gas storage tunnel according to claim 4, characterized in that, The pressure balancing valve (7) also includes a valve cover (76), which is fixedly connected to the upper end of the piston (73).

6. The crack repair device for the lining of a gas storage cavern according to claim 4, characterized in that, The valve body (71) has a boss (77) on its inner wall, which divides the valve body (71) into a second inner cavity (712) located above and a first inner cavity (711) located below. The piston (73) passes through the boss (77), and the first seal (74) is located in the first inner cavity (711).

7. The crack repair device for the lining of a gas storage cavern according to claim 6, characterized in that, The piston (73) is provided with a second seal (78), which is located in the second inner cavity (712) and matches the second inner cavity (712).

8. The crack repair device for the lining of a gas storage cavity according to any one of claims 1 to 7, characterized in that, Several of the grouting holes (8) are arranged in a quincunx pattern on the grouting ring pipe.

9. A crack repair system for the lining (9) of a gas storage cavern, characterized in that, It includes a grouting pump and a crack repair device for the lining of a gas storage cavern as described in any one of claims 1 to 8, wherein the grouting pump is connected to the inlet end of the grouting main pipe.

10. A gas storage cavern, characterized in that, It includes a lining (9) and a sealing layer, as well as a crack repair device for the gas storage cavern lining according to any one of claims 1 to 8 or a crack repair system for the gas storage cavern lining (9) according to claim 9, wherein the grouting main pipe is disposed inside the sealing layer.

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