A pipe ice plug and method

Abstract

This application provides a pipe ice plug sealing device and method. The pipe ice plug sealing device includes: an ice plug forming device, comprising an ice plug jacket and a liquid nitrogen tank, the ice plug jacket and the liquid nitrogen tank being connected; the ice plug jacket is detachably fitted onto the pipe to be ice plugged, and the ice plug jacket has an internal cavity through which liquid nitrogen can flow from the liquid nitrogen tank to freeze the fluid medium inside the pipe; a fixed support for fixing to the outside of the pipe; a deformation measurement system, including a first measuring device and a second measuring device, both of which are fixed to the fixed support and are used to measure the deformation of the pipe; and a control system that, in response to the measurement values ​​from the first measuring device and / or the second measuring device, obtains the deformation of the pipe and controls the freezing process of the ice plug forming device according to the obtained deformation.

Description

Technical Field

[0001] This application relates to the field of pipeline operation and maintenance technology, specifically to a pipeline ice plug sealing device and method. Background Technology

[0002] Ice plug sealing technology involves injecting liquid nitrogen into the ice plug jacket to locally freeze the fluid medium inside the pipeline, forming an ice plug. This allows for online pipeline isolation without shutting down the system and is a crucial supporting technology for the operation and maintenance of nuclear power pipelines.

[0003] During the process of sealing pipelines with ice plugs, the pipeline undergoes complex deformation under the dual effects of rapid cooling and contraction and the freezing and expansion of the internal fluid medium. On the one hand, the cryogenic liquid nitrogen (e.g., about -196°C) exchanges heat with the pipeline, causing the pipe wall to cool and contract rapidly. This deformation effect is dominated by the thermal contraction coefficient of the pipeline material. On the other hand, the fluid medium inside the pipeline freezes and expands in volume (e.g., up to about 9%), which exerts radial pressure on the pipe wall. This superposition of internal and external stresses will cause axial tension, radial expansion, and local buckling of the pipeline. If the deformation exceeds the yield strength of the pipeline material (e.g., the axial tensile limit of stainless steel pipelines is about 1.5 mm / m), it will lead to microcracks in the weld, sealing failure, or even medium leakage. In applications such as nuclear power pipelines, it will also seriously threaten the safety of system operation, forcing the nuclear reactor to shut down urgently and causing economic losses.

[0004] In view of this, this application proposes a pipe ice plugging device and method to solve one or more of the above-mentioned technical problems. Summary of the Invention

[0005] The first aspect of this application is to provide a pipe ice plug sealing device.

[0006] The second aspect of this application is to provide a method for sealing pipe ice plugs.

[0007] According to the first aspect of this application, a pipe ice plug sealing device includes: an ice plug forming device, comprising an ice plug jacket and a liquid nitrogen tank, the ice plug jacket and the liquid nitrogen tank being in communication; the ice plug jacket is detachably fitted onto the pipe to be ice plugged, the ice plug jacket having an internal cavity through which liquid nitrogen can flow from the liquid nitrogen tank to freeze the fluid medium inside the pipe; a fixing bracket for fixing to the outside of the pipe; a deformation measurement system, including a first measuring device and a second measuring device, both the first measuring device and the second measuring device being fixed to the fixing bracket and both being used to measure the deformation of the pipe; and a control system that, in response to measurements from the first measuring device and / or the second measuring device, obtains the deformation of the pipe to control the freezing process of the ice plug forming device based on the deformation.

[0008] The pipe ice plug sealing device provided in this application, while sealing the pipe with an ice plug forming device, can simultaneously detect the pipe's deformation (mainly expansion) in real time using a deformation measurement system. The control system then controls the freezing process of the ice-plugged pipe based on the measurements from the deformation measurement system. This facilitates appropriate adjustment of the freezing rate of the ice-plugged pipe, ensuring the pipe is precisely kept within the allowable deformation threshold. It avoids problems such as excessive expansion due to excessive freezing, leading to cracking, permanent deformation, and other failures. It also avoids excessively restricting the freezing rate without justification, resulting in a long ice plug formation process and low pipe maintenance efficiency. The deformation measurement system is equipped with a first and a second measuring device that simultaneously detects the pipe's deformation. This allows for mutual verification to improve the accuracy of the pipe deformation data obtained by the control system. The two-path deformation measurement also constitutes a redundant design, preventing measurement deviations and control failures caused by the failure of a single measuring device, thus improving the overall operational stability of the pipe ice plug sealing device.

[0009] In some embodiments, the first measuring device is configured as a displacement sensor, the displacement sensor being fixed to the fixed bracket; the second measuring device includes an indicator, a universal bracket, and a support, the indicator being mounted on the support via the universal bracket, the support being fixed to the fixed bracket; and the second measuring device is configured to have at least one of the following: a) the indicator is covered with a heat insulation cover, the heat insulation cover having a sealed vacuum cavity; b) the indicator has a differential structure inside for reducing temperature drift error; c) the indicator includes a titanium alloy body; d) the indicator includes a ceramic measuring rod; e) the universal bracket includes a titanium alloy support arm.

[0010] In some embodiments, the indicator is configured to be readable by a mechanical pointer and to acquire data to provide the indicator's measured value to the control system; and / or, the support is a magnetic support that is detachably fixed to the mounting bracket.

[0011] In some embodiments, the first measuring device and the second measuring device are selected from one of an inductive displacement sensor, a laser displacement sensor and a magnetostrictive displacement sensor, respectively, and the first measuring device and the second measuring device are of different types.

[0012] In some embodiments, the pipe to be ice-plugged is configured as a sleeve, the sleeve including an inner pipe and an outer pipe, the inner pipe and the outer pipe forming an annular cavity, the annular cavity being connected to a pump and equipped with a pressure gauge to simulate the working conditions of the inner pipe; the ice plug clamp is fitted onto the outer pipe, the fixing bracket is fixed to the outside of the outer pipe, and the first measuring device and the second measuring device are used to measure the deformation of the inner pipe.

[0013] In some embodiments, the mounting bracket is provided with a mounting platform, which provides mounting positions for a plurality of the first measuring devices and / or a plurality of the second measuring devices.

[0014] In some embodiments, the control system is configured to: compare the deformation obtained by the control system with a preset threshold; if it is determined that the deformation obtained by the control system is greater than the preset threshold, output an instruction to adjust the liquid nitrogen flow rate in the cavity or stop freezing, so as to prevent the pipeline from expanding beyond the limit.

[0015] In some embodiments, the control system is configured to: obtain the measurement values ​​obtained by the first measuring device and the second measuring device, and process the measurement values ​​based on a Kalman filter algorithm to obtain the pipeline expansion amount obtained by the control system.

[0016] In some embodiments, the control system further includes a wireless communication module, through which the control system communicates wirelessly with the first measuring device and the second measuring device; and / or, the control system further includes a temperature sensor for measuring the temperature of the pipe, and the control system responds to the measured value of the temperature sensor and corrects the deformation obtained by the control system according to the coefficient of thermal expansion of the pipe material.

[0017] The pipeline ice plugging method according to the second aspect of this application employs the pipeline ice plugging device as described in the first aspect to achieve pipeline ice plugging, including: When the ice plug forming device seals the pipe with an ice plug, the deformation of the pipe is measured by the deformation measurement system. The control system controls the freezing process of the ice plug forming device in response to the measured value obtained by the deformation measurement system to avoid pipe failure. Attached Figure Description

[0018] The above and other features, properties and advantages of this application will become more apparent from the following description taken in conjunction with the accompanying drawings and embodiments, in which the same reference numerals always denote the same features. It should be noted that these drawings are merely illustrative and are not drawn to scale, and should not be construed as limiting the scope of protection actually claimed by this application.

[0019] Figure 1 This is a schematic diagram of the pipe ice plug sealing device and the pipe to be sealed, according to one embodiment.

[0020] Figure 2 This is a schematic flowchart of a pipeline ice plug sealing method according to one embodiment.

[0021] Explanation of reference numerals in the attached figures: 1. Pipeline ice plug sealing device; 10. Ice stopper forming device; 11. Ice stopper jacket; 12. Liquid nitrogen tank; 20. Fixed bracket; 21. Mounting platform; 30. Deformation measurement system; 31. First measuring device; 32. Second measuring device; 321. Indicator; 322. Universal bracket; 323. Support; 40. Control system; 2. Pipeline. Detailed Implementation

[0022] Reference will now be made in detail to various embodiments of this application, examples of which are shown in the accompanying drawings and described below. Although this application will be described in conjunction with exemplary embodiments, it should be understood that this application is not intended to be limited to those exemplary embodiments. Rather, this application is intended to cover not only these exemplary embodiments, but also various alternatives, modifications, equivalents, and other embodiments that may be included within the spirit and scope of this application as defined by the appended claims.

[0023] This application uses specific terms to describe embodiments of the application. For example, "an embodiment" and / or "one embodiment" refers to a particular feature, structure, or characteristic associated with at least one embodiment of the application. Therefore, it should be emphasized and noted that "an embodiment" or "one embodiment" mentioned twice or more in different locations in this application does not necessarily refer to the same embodiment. Furthermore, certain features, structures, or characteristics in one or more embodiments of the application can be appropriately combined.

[0024] In this application, the terms "first," "second," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying positional relationships or order of importance.

[0025] In the following description, the orientation or positional relationship indicated by terms such as "upper," "lower," "inner," "outer," "front," "back," or other directional terms is based on the orientation or positional relationship shown in the accompanying drawings and is only for the convenience of describing this application and simplifying the description, and is not intended to indicate or imply that the device or component referred to must have a specific orientation, be constructed and / or be implemented in a specific orientation, and therefore should not be construed as a limitation of this application.

[0026] In the following description, unless otherwise expressly specified or limited, the terms "installation," "connection," "linking," "fixing," "contact," etc., should be interpreted broadly; for example, they can refer to fixed connections or movable connections; they can refer to direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of these terms in the embodiments of this application according to the specific circumstances.

[0027] It is understood that the pipe ice plug sealing device and method provided in this application are particularly suitable for freezing and isolating nuclear power pipelines with ice plugs to facilitate in-situ pipeline maintenance and other operations. They can also be applied to other applicable occasions, such as in-situ maintenance of other types of pipelines or pipe ice plug sealing tests, and are not limited thereto.

[0028] See Figure 1 As shown, the pipe ice plug sealing device 1 provided in this application includes: an ice plug forming device 10, a fixed bracket 20, a deformation measurement system 30, and a control system 40.

[0029] The ice plug forming device 10 includes an ice plug jacket 11 and a liquid nitrogen tank 12, which are connected, for example, through a delivery pipeline. The ice plug jacket 11 is detachably fitted onto the pipe 2 to be ice plugged, and has an internal cavity into which liquid nitrogen can be injected from the liquid nitrogen tank 12 to freeze the fluid medium inside the pipe 2. The ice plug jacket 11 can be configured to include a first assembly and a second assembly, both of which have a hollow structure and can be assembled and fixed at the position of the pipe 2 to be ice plugged, thus together forming the entire ice plug jacket 11.

[0030] The fixing bracket 20 is used to fix it to the outside of the pipe 2.

[0031] The deformation measurement system 30 includes a first measuring device 31 and a second measuring device 32, both of which are fixed to the fixed support 20 and are used to measure the deformation of the pipe 2.

[0032] Generally, the first measuring device 31 and the second measuring device 32 are configured as displacement sensors to measure the displacement of measuring points characterizing the deformation of the pipe 2, so as to obtain the measured values ​​of the radial and / or axial deformation of the pipe 2.

[0033] The control system 40 determines the deformation of the pipe 2 in response to the measurements from the first measuring device 31 and / or the second measuring device 32, and controls the freezing process of the ice plug forming device 10 based on the determined deformation.

[0034] Generally, the control system 40 includes a memory and a processor. The memory stores instructions that can be executed by the processor, which executes the instructions from the memory to calculate and process the deformation (mainly the expansion) of the pipe 2 based on the measurements from the first measuring device 31 and / or the second measuring device 32, and generates a control command for the freezing process based on the comparison result of the real-time obtained deformation of the pipe 2 with a preset threshold. The actuator in the ice plug forming device 10 controls the freezing process in response to the control command. The actuator is, for example, a valve, which can adjust the flow rate of liquid nitrogen and / or control the on / off of liquid nitrogen to the ice plug jacket 11 to start or stop the freezing process, etc.

[0035] Using the pipe ice plug sealing device 1 provided in this application, while sealing the pipe 2 with the ice plug forming device 10, the deformation measurement system 30 can detect the deformation (mainly expansion) of the pipe 2 in real time. The control system 40 controls the freezing process of the ice plug-sealed pipe 2 based on the measurement values ​​of the deformation measurement system 30. This is beneficial for appropriately adjusting the freezing rate of the ice plug-sealed pipe 2, keeping the pipe 2 precisely within the allowable deformation threshold. This avoids problems such as excessive expansion of the pipe 2 due to excessive freezing rate, leading to cracking, permanent deformation, and other failures. It also avoids excessively restricting the freezing rate without basis in order to protect the pipe 2, resulting in a long ice plug formation process and low maintenance efficiency of the pipe 2. The deformation measurement system 30 is equipped with a first measuring device 31 and a second measuring device 32 to synchronously detect the deformation of the pipe 2. This is suitable for mutual verification to improve the accuracy of the pipe 2 deformation obtained by the control system 40. The deformation measurement of the two paths also constitutes a redundant design, avoiding measurement deviation and control failure caused by the failure of a single measuring device, and improving the overall operational stability of the pipe ice plug sealing device 1.

[0036] In some embodiments, the first measuring device 31 is configured as a displacement sensor, which is fixed to the fixed bracket 20; the second measuring device 32 includes an indicator 321, a universal bracket 322 and a support 323, the indicator 321 is mounted on the support 323 via the universal bracket 322, and the support 323 is fixed to the fixed bracket 20.

[0037] The dial gauge 321 mentioned here refers to a mechanical displacement measuring instrument, which can generally be divided into dial indicators, micrometer indicators, etc., according to the measurement accuracy. During measurement, the probe of the dial gauge 321 abuts against the surface of the object being measured (pipe wall), converting the movement (deformation) of the object's surface into linear displacement of the probe and measuring rod. Based on this linear displacement, the amount of movement (deformation) of the object being measured is determined. Generally, the dial gauge 321 also has an internal mechanical transmission mechanism to amplify the linear displacement of the measuring rod, thereby improving the resolution of the displacement measurement. The dial gauge 321 can be used with a measuring range of ±5mm and a resolution of 0.001mm, but is not limited to this.

[0038] Optionally, the indicator 321 is covered with a heat insulation cover, which has a sealed vacuum chamber. This helps to isolate the indicator 321 from heat exchange with the external environment and reduce the temperature drift error of the indicator 321.

[0039] Optionally, the indicator 321 is internally equipped with a differential structure to reduce temperature drift error, thereby compensating for the deformation of the indicator 321 components in the low-temperature environment of the ice-plugged pipeline 2 and reducing the temperature drift error of the indicator 321. Specifically, this differential structure may be configured with beryllium bronze components, thereby relying on the stable thermal expansion coefficient and elastic temperature characteristics of beryllium bronze to achieve temperature drift error compensation. The core functional component of this differential structure can be configured to be made of a single beryllium bronze material. Utilizing the inherent characteristics of beryllium bronze's elastic modulus and thermal expansion changing with temperature, a differential cancellation relationship is formed with the temperature change effect of other supporting components inside the indicator 321. When the low-temperature environment of the ice plugging operation causes temperature change elastic force offset and dimensional deformation errors in the transmission and measurement components of the indicator 321, the synchronous modulus change and thermal expansion deformation of the beryllium bronze components can correspondingly offset the errors caused by the aforementioned temperature changes, thereby compensating for the overall deformation deviation of the indicator 321 and reducing temperature drift error. Alternatively, the core functional component of this differential structure can be configured as a composite structure made of multiple metal materials, such as a beryllium bronze layer bonded with a low-expansion alloy layer. When the ambient temperature changes, the difference in the thermal expansion coefficients of the multiple metal materials will produce a difference in expansion and contraction, which will drive the composite component to produce differential deformation in the opposite direction to the internal thermal deformation of the indicator 321. This will automatically compensate for the offset of the fitting clearance and the drift of the measuring pressure caused by the temperature change inside the indicator 321, and ensure the measurement accuracy of the indicator 321 under wide temperature conditions.

[0040] Optionally, the indicator 321 includes a titanium alloy body and / or a ceramic measuring rod, and / or the universal bracket 322 includes a titanium alloy support arm. Materials such as titanium alloy and ceramic have high dimensional stability in low-temperature environments, which helps to avoid measurement errors caused by low-temperature deformation of the body, measuring rod and universal bracket 322.

[0041] In some embodiments, indicator 321 is configured to be readable by a mechanical pointer to ensure manual reading in case of emergency; and indicator 321 is also configured to be able to collect data to provide the measurement value of indicator 321 to control system 40.

[0042] In practice, an example of a pipe ice plug sealing device 1 is configured as follows: the indicator 321 of the second measuring device 32 is covered with a heat insulation cover, the heat insulation cover has a sealed vacuum cavity, and the inside of the indicator 321 has a differential structure including beryllium bronze components to reduce temperature drift error. The indicator 321 includes a titanium alloy body and a ceramic measuring rod, and the universal bracket 322 includes a titanium alloy support arm. Thus, the indicator 321 has good low-temperature resistance and can achieve high-precision measurement within the range of ±0.005mm in a low-temperature environment of about -196℃. Furthermore, the indicator 321 supports mechanical pointer reading to retain the function of manual reading, and also supports data acquisition to provide its measured values ​​to the control system 40. The control system 40, based on the measured values ​​of the first measuring device 31 (which is configured as an inductive displacement sensor) and the second measuring device 32, processes the data using a Kalman filter algorithm to obtain the expansion amount of the pipe 2, which can achieve digital real-time monitoring feedback with a resolution of 0.1μm.

[0043] In some embodiments, the support 323 is a magnetic support, which is detachably fixed to the fixed bracket 20. The use of the magnetic support and the universal bracket 322 facilitates flexible adjustment of the installation and measurement position of the indicator 321, and ensures the perpendicularity of the measuring rod of the indicator 321 to the surface of the object being measured.

[0044] In some embodiments, the first measuring device 31 and the second measuring device 32 are configured as displacement sensors, and are selected from inductive displacement sensors, laser displacement sensors, and magnetostrictive displacement sensors, and the first measuring device and the second measuring device are of different types. Using displacement sensors with different measurement principles in this way can improve the accuracy of deformation calculation results based on the fusion of measurement values ​​from two paths, for example, through Kalman filtering or other applicable filtering algorithms, and avoids system failure due to the failure of a displacement sensor with a single measurement principle caused by operating condition interference, thus improving overall operational stability.

[0045] like Figure 1As shown, in some embodiments, the pipeline ice plug sealing device 1 is used for pipeline ice plug sealing tests. The pipeline 2 to be ice plugged is configured as a sleeve, which includes an inner pipe fitting and an outer pipe fitting. The inner and outer pipe fittings form an annular cavity, which is connected to a pump and equipped with a pressure gauge to simulate the working environment of the inner pipe fitting. The end of the inner pipe fitting extends out of the outer pipe fitting for deformation measurement. The ice plug clamp 11 is fitted onto the outer pipe fitting, and the fixing bracket 20 is fixed to the outside of the outer pipe fitting. The first measuring device 31 and the second measuring device 32 are used to measure the deformation of the end of the inner pipe fitting. This design provides a test device for ice plug sealing sleeve-type structures, which can realistically simulate the working conditions of the inner pipe fitting and directly detect the deformation of the inner pipe fitting. The expansion change curve of the pipeline 2 can be collected and recorded in real time through the deformation measurement system 30, thereby providing experimental data support for parameter control and inner pipe fitting protection methods for ice plug sealing of sleeve-type structures in actual maintenance operations.

[0046] Furthermore, the pipe ice plug sealing device 1 can be configured such that: the fixed bracket 20 is Figure 1 The bracket shown features a triangular support structure and provides multiple support points along the axial direction of pipe 2, facilitating the stable installation of the expansion measurement system to ensure measurement accuracy. The fixed bracket 20 provides a mounting platform 21 at the end adjacent to the sleeve, on which the first measuring device 31 and / or the second measuring device 32 are mounted, enabling direct measurement of the end face of the inner pipe fitting to obtain its axial expansion. It is understood that since this test detects the deformation of the inner pipe fitting, and the outer pipe fitting is fixedly connected to the fixed bracket 20, the deformation measurement system 30 can also be arranged on the outer pipe fitting, without limitation.

[0047] In practice, one example used the pipe ice plugging device 1 provided in this application to perform ice plugging operations on a nuclear power pipe 2 made of 316L stainless steel with an outer diameter range of DN50-DN300. The risk of the axial expansion of the pipe 2 exceeding the limit was reduced to less than 0.5%, and the entire ice plug formation process was shortened to about 8-12 minutes.

[0048] In some embodiments, the mounting bracket 20 is provided with a mounting platform 21, which provides mounting positions for a plurality of first measuring devices 31 and / or a plurality of second measuring devices 32 to facilitate the measurement of the deformation of the pipe 2 in different directions and positions. Further, the mounting positions of the plurality of first measuring devices 31 and / or the plurality of second measuring devices 32 can also be configured to measure the deformation of the pipe 2 in three-dimensional orthogonal directions, such as the axial direction of the pipe 2 and two mutually perpendicular radial directions.

[0049] In some embodiments, the control system 40 is configured to: compare the deformation obtained by the control system 40 with a preset threshold; if it is determined that the deformation obtained by the control system 40 is greater than the preset threshold, then output a control command to adjust the liquid nitrogen flow rate in the cavity or stop freezing, so as to prevent the expansion of the pipeline 2 from exceeding the limit. It can be understood that the control strategy can also make the deformation during the freezing process tend to the preset threshold, thereby improving the ice plug formation speed and maintenance efficiency while ensuring that the deformation does not exceed the allowable range.

[0050] In some embodiments, the control system 40 is configured to: obtain the measurement values ​​obtained by the first measuring device 31 and the second measuring device 32, and perform calculation processing on the measurement values ​​based on the Kalman filter algorithm to correct the deformation, which is beneficial to improving the accuracy of deformation monitoring.

[0051] In some embodiments, the control system 40 further includes a wireless communication module, through which the control system 40 communicates with the first measuring device 31 and the second measuring device 32, and is adapted to be deployed in complex field environments such as nuclear power pipeline 2.

[0052] In some embodiments, the control system 40 further includes a temperature sensor for measuring the temperature of the pipe 2. The control system 40 responds to the measured value of the temperature sensor and corrects the expansion amount of the pipe 2 obtained by the control system 40 according to the thermal expansion coefficient of the pipe 2 material, so that the monitoring of the expansion amount of the pipe 2 is more accurate.

[0053] like Figure 2 As shown, this application also provides a method for sealing ice plugs in pipeline 2, which uses the pipeline ice plugging device 1 described above to seal the pipeline 2 with ice plugs, including: When the ice plug forming device 10 blocks the pipe 2 with ice plug, the deformation of the pipe 2 is measured by the deformation measurement system 30. The control system 40 controls the freezing process of the ice plug forming device 10 in response to the measured value obtained by the deformation measurement system 30 to avoid failure of the pipe 2.

[0054] The ice plug sealing method for pipeline 2 provided in this application can monitor the deformation (expansion) of pipeline 2 in real time during the freezing process. This can effectively reduce the risk of pipeline 2 expanding beyond the limit and avoid damage and failure of pipeline 2. It can also effectively accelerate the ice plug formation speed and maintenance efficiency while protecting pipeline 2 by precisely keeping the expansion of pipeline 2 within the allowable deformation threshold.

[0055] Specifically, in some embodiments, the first measuring device 31 includes a displacement sensor, and the second measuring device 32 includes an indicator 321. The method of sealing the pipe 2 with ice plug includes: S1. Pre-calibration: The measurement zero point is calibrated under normal temperature conditions (within the range of 10℃ to 30℃), and the reference length for measuring the deformation of the pipeline to be sealed with ice plug is set. S2. Installation and positioning: Attach the magnetic support to the fixed bracket 20 adjacent to the ice plug jacket 11, and adjust the probe of the indicator 321 to abut against the wall of the pipe 2 to be sealed with ice plug. S3. Synchronous detection: Liquid nitrogen is injected into the cavity of the ice plug jacket 11 for freezing. The deformation of the pipe 2 to be blocked is collected synchronously and in real time through the displacement sensor and indicator 321, and the measurement data is wirelessly transmitted to the control terminal. S4. Dynamic compensation: Based on the thermal expansion coefficient of the material of the pipe 2 to be sealed, and combined with the real-time temperature data of the pipe wall collected by the temperature sensor, the nonlinear temperature error calculated by the deformation is corrected to obtain a more accurate deformation of the pipe 2 to be sealed. S5. Safety warning: Compare the deformation (expansion) determined in real time by the control system 40 with the corresponding preset threshold; if it is determined that the expansion exceeds the preset threshold, the control system 40 generates a control command to automatically adjust the liquid nitrogen delivery flow rate or disconnect the liquid nitrogen delivery to suspend the freezing process, and issues a warning.

[0056] It should be noted that before measuring the deformation of pipe 2 with indicator 321, the surface of pipe 2 should be cleaned to remove oil and oxide layers. Pipe 2 can also be pre-polished, which helps to reduce measurement interference.

[0057] In summary, the beneficial technical effects of this application include, but are not limited to, at least one of the following: The pipe ice plug sealing device provided in this application, while sealing the pipe with an ice plug forming device, can simultaneously detect the pipe's deformation (mainly expansion) in real time using a deformation measurement system. The control system then controls the freezing process of the ice-plugged pipe based on the measurements from the deformation measurement system. This facilitates appropriate adjustment of the freezing rate of the ice-plugged pipe, ensuring the pipe is precisely kept within the allowable deformation threshold. It avoids problems such as excessive expansion due to excessive freezing, leading to cracking, permanent deformation, and other failures. It also avoids excessively restricting the freezing rate without justification, resulting in a long ice plug formation process and low pipe maintenance efficiency. The deformation measurement system is equipped with a first and a second measuring device that simultaneously detects the pipe's deformation. This allows for mutual verification to improve the accuracy of the pipe deformation data obtained by the control system. The two-path deformation measurement also constitutes a redundant design, preventing measurement deviations and control failures caused by the failure of a single measuring device, thus improving the overall operational stability of the pipe ice plug sealing device.

[0058] It is understood that the aforementioned memory and processor are not limited to a specific memory or processor. For example, in some cases, the memory and / or processor have a distributed structure. For instance, it may include a memory and processor located at the measurement device end and the back-end cloud respectively, with the measurement device end and the back-end cloud jointly implementing the above-mentioned test method. Furthermore, in embodiments employing a distributed structure, the specific execution terminal for each step of the test method can be adjusted according to actual conditions, and the specific implementation scheme of each step on a particular terminal should not limit the scope of protection of this invention.

[0059] While this application discloses preferred embodiments as described above, it is not intended to limit the scope of this application. Any changes and modifications can be made by those skilled in the art without departing from the spirit and scope of this application. Therefore, any modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the content of the technical solution of this application shall fall within the protection scope defined by the claims of this application.

Claims

1. A pipe ice plug sealing device, characterized in that, include: An ice plug forming device includes an ice plug jacket and a liquid nitrogen tank, wherein the ice plug jacket and the liquid nitrogen tank are connected; the ice plug jacket is used to be detachably fitted onto the pipe to be ice plugged, and the ice plug jacket has a cavity inside, through which liquid nitrogen can flow from the liquid nitrogen tank to freeze the fluid medium inside the pipe; A fixing bracket is used to fix the pipe to the outside; The deformation measurement system includes a first measuring device and a second measuring device, which are fixed to the fixed support and are both used to measure the deformation of the pipe. The control system, in response to measurements from the first measuring device and / or the second measuring device, obtains the deformation of the pipe to control the freezing process of the ice plug forming device based on the deformation.

2. The pipe ice plug sealing device according to claim 1, characterized in that, The first measuring device is configured as a displacement sensor, which is fixed to the fixed bracket; the second measuring device includes an indicator, a universal joint, and a support, wherein the indicator is mounted on the support via the universal joint, and the support is fixed to the fixed bracket; and the second measuring device is configured as at least one of the following: a) The indicator is covered by a heat insulation cover, and the heat insulation cover is provided with a sealed vacuum cavity; b) The indicator is internally equipped with a differential structure to reduce temperature drift error; c) The indicator includes a titanium alloy body; d) The indicator includes a ceramic measuring rod; e) The universal bracket includes a titanium alloy support arm.

3. The pipe ice plug sealing device according to claim 2, characterized in that, The indicator is configured to be readable by a mechanical pointer and to acquire data to provide the indicator's measured value to the control system; and / or, the support is a magnetic support that is detachably fixed to the fixed bracket.

4. The pipe ice plug sealing device according to claim 1, characterized in that, The first measuring device and the second measuring device are respectively selected from one of an inductive displacement sensor, a laser displacement sensor and a magnetostrictive displacement sensor, and the first measuring device and the second measuring device are of different types.

5. The pipe ice plug sealing device according to claim 1, characterized in that, The pipe to be ice-plugged is configured as a sleeve, which includes an inner pipe and an outer pipe, forming an annular cavity. The annular cavity is connected to a pump and equipped with a pressure gauge to simulate the operating conditions of the inner pipe. The ice plug is fitted onto the outer pipe, and the fixing bracket is fixed to the outside of the outer pipe. The first measuring device and the second measuring device are used to measure the deformation of the inner pipe.

6. The pipe ice plug sealing device according to claim 1, characterized in that, The fixed bracket is provided with an installation platform, which provides installation positions for multiple first measuring devices and / or multiple second measuring devices.

7. The pipe ice plug sealing device according to claim 1, characterized in that, The control system is configured to compare the deformation obtained by the control system with a preset threshold. If it is determined that the deformation obtained by the control system is greater than the preset threshold, an instruction to adjust the liquid nitrogen flow rate in the cavity or stop freezing is output to prevent the pipeline from expanding beyond the limit.

8. The pipe ice plug sealing device according to claim 1, characterized in that, The control system is configured to: obtain the measured values ​​obtained by the first measuring device and the second measuring device, and process the measured values ​​based on the Kalman filter algorithm to obtain the deformation.

9. The pipe ice plug sealing device according to claim 1, characterized in that, The control system further includes a wireless communication module, through which the control system communicates wirelessly with the first measuring device and the second measuring device; and / or The control system further includes a temperature sensor for measuring the temperature of the pipe, and the control system responds to the measured value of the temperature sensor and corrects the pipe expansion obtained by the control system according to the thermal expansion coefficient of the pipe material.

10. A method for sealing ice plugs in pipelines, characterized in that, Pipeline ice plugging is achieved by using the pipeline ice plugging device as described in any one of claims 1 to 9, comprising: When the ice plug forming device seals the pipe with an ice plug, the deformation of the pipe is measured by the deformation measurement system. The control system controls the freezing process of the ice plug forming device in response to the measured value obtained by the deformation measurement system to avoid pipe failure.

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