Petrochemical engineering pipeline under-pressure leaking stoppage method

Abstract

The invention discloses an under-pressure plugging method for a petrochemical pipeline. The under-pressure plugging method comprises the steps that S1, a plugging system of a shape memory alloy element and a miniature vacuum pump is constructed; s2, adjusting the sealing pressure of an SMA element, and constructing a sealing pressure control function of the SMA element; s3, negative pressure adsorption cooperative control; s4, system self-adaptive adjustment and feedback are carried out; and S5, the leaking stoppage effect is evaluated, and periodic self-inspection and adjustment are Through the SMA element and the miniature vacuum pump, a pipeline sealing system is accurately adjusted by utilizing a self-adaptive sealing pressure control and negative pressure adsorption cooperation technology, and pipeline leakage can be effectively repaired under the condition that normal operation of a pipeline is not affected.

Description

Technical Field

[0001] The invention relates to the technical field of pipeline pressure plugging, and in particular to a petrochemical pipeline pressure plugging method. Background Art

[0002] During the long-term use of petrochemical pipelines, pipeline leakage often occurs. Traditional pipeline leak plugging methods usually rely on mechanical structures or chemical sealing materials to plug leaks, but these methods often cannot work effectively under high pressure, high temperature and harsh environments. With the advancement of technology, pressure plugging technology has become an important means to solve pipeline leakage problems.

[0003] Most of the existing pressure plugging methods rely on manual operation or a single sealing mechanism, such as mechanical plugs or adhesives. These methods are difficult to cope with complex factors such as residual pressure in the pipeline and temperature fluctuations. Traditional methods cannot adaptively adjust according to changes in the environment inside and outside the pipeline. The sealing effect is easily affected by external conditions, especially under high temperature and frequent pressure changes. The sealing effect is often unstable. Summary of the invention

[0004] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0005] In view of the problems existing in the above-mentioned existing petrochemical pipeline pressure plugging method, the present invention is proposed.

[0006] Therefore, the purpose of the present invention is to provide a method for plugging leaks in petrochemical pipelines under pressure, which is suitable for solving the problem that the sealing effect cannot be adaptively adjusted according to changes in the internal and external environment of the pipeline, and is easily affected by external conditions, especially under high temperature and frequent pressure changes, and the sealing effect is often unstable.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions: a method for plugging leaks in a petrochemical pipeline under pressure, comprising:

[0008] S1: Construction of a leak plugging system using shape memory alloy elements and micro vacuum pumps;

[0009] S2: SMA element sealing pressure adjustment, building the SMA sealing pressure control function;

[0010] S3: Negative pressure adsorption coordinated control;

[0011] S4: System adaptive adjustment and feedback;

[0012] S5: Evaluation of leak plugging effect, periodic self-inspection and adjustment.

[0013] As a preferred solution of the method for plugging leaks in a petrochemical pipeline under pressure described in the present invention, the sealing pressure control function of the SMA is as follows:

[0014]

[0015] Among them, P seal (T,P pipe ,t) Sealing pressure calculated based on SMA adaptive sealing control, T is the real-time temperature of the pipeline, T0 is the phase change temperature of SMA, P pipe is the pressure difference between the inside and outside of the pipeline, t is the time, α and β are the influence coefficients of temperature change on alloy deformation and pressure attenuation, γ and δ represent the influence intensity of time and pressure on the sealing effect, ζ and ω are oscillation factors, which are used to simulate the dynamic response of the alloy under load.

[0016] As a preferred solution of the method for plugging leaks in a petrochemical pipeline under pressure described in the present invention, the initial sealing pressure threshold value P is set in the output result of the sealing pressure control function of the SMA. seal，init , critical sealing pressure threshold P seal，crit and safety sealing pressure threshold P seal，safe ;

[0017] Based on the thresholds set above, the following judgment process is used to ensure that the plugging method is always in a reasonable working state;

[0018] Initialization check: Calculate the initial sealing pressure P seal (T,P pipe , t=0), if P seal <P seal，init , start the temperature control system and adjust the response characteristics of the SMA until the sealing pressure reaches P seal，init ;

[0019] Dynamic adjustment and monitoring:

[0020] During the pipeline operation, the sealing pressure is monitored regularly and the pressure difference P between the inside and outside of the pipeline is calculated based on the real-time temperature T and the pressure difference P between the inside and outside of the pipeline. pipe , the sealing pressure is automatically adjusted through the temperature response characteristics of SMA;

[0021] If P seal (T,P pipe ,t)<P seal，crit , triggering an alarm and starting heating or adjusting the sealing system to restore the sealing effect;

[0022] If P seal (T,P pipe ,t)>Pseal，safe , by reducing the pressure in the pipeline or adjusting the response of the sealing material through the automatic control subsystem to avoid system overload;

[0023] Long-term operation monitoring:

[0024] During long-term operation, the sealing pressure P is continuously monitored. seal changes, especially when there are dramatic changes in temperature or pressure;

[0025] If the sealing pressure is lower than P for a long time seal，init or higher than P seal，safe , automatically enters the system maintenance mode to check whether the system is faulty or needs to replace the SMA component.

[0026] As a preferred solution of the method for plugging leaks in a petrochemical pipeline under pressure described in the present invention, the negative pressure adsorption coordinated control is achieved by the following steps:

[0027] S31: Use a micro vacuum pump and a pressure sensor to establish a local negative pressure environment. When plugging a leak, the sensor monitors the pressure changes in the pipeline in real time.

[0028] S32: Combined with the pipeline pressure information fed back by the pressure sensor, the suction force of the micro vacuum pump is automatically adjusted to construct a residual pressure balance calculation formula;

[0029] S33: Through the control subsystem, the negative pressure and the action timing of the SMA sealing element are precisely adjusted.

[0030] As a preferred solution of the method for plugging leaks in a petrochemical pipeline under pressure described in the present invention, the residual pressure balance calculation formula is as follows:

[0031]

[0032] Among them, P residual (t) is the residual pressure in the pipeline at a certain moment.

[0033] As a preferred solution of the method for plugging leaks in a petrochemical pipeline under pressure described in the present invention, a negative pressure adsorption control formula is constructed according to the output result of the residual pressure balance calculation formula, and the negative pressure adsorption control formula is as follows:

[0034]

[0035] Among them, P seal,adj (t) is the sealing pressure after negative pressure adsorption adjustment, l is the amplitude of negative pressure adjustment, It is the adjustment frequency of the negative pressure adsorption system.

[0036] As a preferred solution of the method for plugging leaks in a petrochemical pipeline under pressure described in the present invention, an interactive judgment is performed based on the output result of the negative pressure adsorption control formula combined with the output result of the sealing pressure control function of the SMA;

[0037] If P seal,adj (t)<P seal，init or P seal,adj (t)<P seal，crit , it means that the sealing pressure is insufficient and it is necessary to adjust the negative pressure adsorption system or the response of the shape memory alloy to enhance the sealing effect;

[0038] If P seal,adj (t)>P seal，safe , it means that the sealing pressure is too high, and it is necessary to reduce the negative pressure adsorption strength or adjust the working state of the shape memory alloy to reduce the sealing pressure;

[0039] If P seal,adj (t) If the fluctuation is too large within a certain period of time, it means that the sealing system is unstable. This is caused by the imbalance between the negative pressure adsorption system and the shape memory alloy response, and the adjustment mechanism needs to be further optimized.

[0040] As a preferred solution of the method for plugging leaks in a petrochemical pipeline under pressure described in the present invention, the plugging system comprises:

[0041] SAM sealing element: embedded in the pipeline sealing structure, adjusting the sealing pressure through temperature changes;

[0042] Negative pressure regulating device: A micro vacuum pump is used in conjunction with a pressure sensor to create a local negative pressure environment when plugging leaks, thereby offsetting the effect of residual pressure in the pipeline on the seal;

[0043] Temperature and pressure sensors: used to monitor the temperature and pressure of the pipeline in real time and provide feedback to the control subsystem;

[0044] Control subsystem: adjust the state and negative pressure intensity of the SAM element in real time.

[0045] As a preferred solution of the method for plugging leaks in a petrochemical pipeline under pressure described in the present invention, the system adaptive adjustment and feedback are achieved by the following steps:

[0046] S41, adaptive feedback mechanism: the temperature sensor and pressure sensor feed back the real-time monitoring data to the control subsystem, and the control subsystem automatically adjusts the deformation of the SMA element and the intensity of negative pressure adsorption according to the feedback;

[0047] S42. Use neural networks to analyze and optimize the plugging process in real time, and adjust the operating parameters of the SMA sealing element and the negative pressure pump to adapt them to different pipeline working conditions and leakage levels.

[0048] As a preferred solution of the method for plugging leaks in a petrochemical pipeline under pressure described in the present invention, S5 comprises the following steps:

[0049] S51: monitor the pressure change of the pipeline after plugging through the sensor to evaluate the stability of the plugging effect. After sealing, if the pressure fluctuation is within the predetermined range, it means that the sealing effect is good;

[0050] S52: After the plugging operation is completed, the system will perform self-inspection regularly to check the deformation state of the SMA element and the stability of the negative pressure environment to ensure that a good sealing effect can be maintained during long-term operation.

[0051] Beneficial effects of the present invention: Through the SMA element and the micro vacuum pump, the adaptive sealing pressure control and negative pressure adsorption synergistic technology are used to achieve precise adjustment of the pipeline sealing system. This method has a wide range of application scenarios, especially in the fields of petrochemical industry, high-pressure gas transportation, etc., and can effectively repair pipeline leakage without affecting the normal operation of the pipeline;

[0052] SMA components can automatically adjust the sealing pressure when the temperature changes, respond to pipeline temperature changes in real time, and compensate for sealing failure caused by thermal expansion and contraction. The micro vacuum pump is used in conjunction with the pressure sensor to create a local negative pressure environment during the plugging process. By real-time monitoring of the pressure changes in the pipeline, the suction force of the micro vacuum pump is accurately adjusted to achieve the balance of the residual pressure. By automatically adjusting the negative pressure intensity, the influence of the residual pressure in the pipeline on the sealing system can be effectively offset. The control subsystem can automatically adjust the deformation and negative pressure adsorption intensity of the SMA component to adapt to different working environments and leakage conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0054] Figure 1 This is a schematic diagram of the overall process of a method for plugging leaks in a petrochemical pipeline under pressure proposed by the present invention;

[0055] Figure 2 The present invention provides a schematic diagram of a plugging system framework for a petrochemical pipeline pressure plugging method. DETAILED DESCRIPTION

[0056] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0057] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0058] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0059] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0060] Embodiment 1

[0061] Reference Figure 1-Figure 2 , as one embodiment of the present invention, provides a method for plugging leaks in a petrochemical pipeline under pressure, comprising:

[0062] S1: Construction of a leak plugging system using shape memory alloy elements and micro vacuum pumps;

[0063] The leak plugging system includes:

[0064] SAM sealing element: embedded in the pipeline sealing structure, adjusting the sealing pressure through temperature changes;

[0065] SMA materials undergo different phase changes at different temperatures, causing changes in their shape and size, thereby achieving adaptive adjustment of the sealing state. Common shape memory alloy materials include copper-aluminum alloys, nickel-titanium alloys (NiTi), etc. These alloys have significant shape changes between high and low temperatures, and can automatically shrink when the temperature of the pipeline rises, and expand when the temperature drops, thereby adjusting the sealing pressure. SMA elements are designed as annular or ribbon structures, embedded in the sealing part of the pipeline, and directly act on the sealing layer around the leak point;

[0066] Negative pressure regulating device: A micro vacuum pump is used in conjunction with a pressure sensor to create a local negative pressure environment when plugging leaks, thereby offsetting the effect of residual pressure in the pipeline on the seal;

[0067] The micro vacuum pump creates a negative pressure environment in a local area. The power and suction of the pump need to be adjusted according to the residual pressure in the pipeline and the sealing layer requirements. The pressure sensor is used to monitor the pressure in the pipeline in real time and feed it back to the control subsystem. By accurately measuring the pressure changes at the leakage point, the sensor helps the control subsystem adjust the negative pressure intensity in real time.

[0068] Temperature and pressure sensors: used to monitor the temperature and pressure of the pipeline in real time and provide feedback to the control subsystem;

[0069] Temperature sensor: Commonly used temperature sensors include thermocouples, RTD (thermistor) sensors, etc., which can accurately measure the temperature changes at the pipeline leakage point and the surrounding area;

[0070] Pressure sensor: The pressure sensor can use strain gauges, piezoelectric sensors and other types to provide feedback data based on the pressure difference inside and outside the pipeline to help the system determine the severity of the leak;

[0071] Control subsystem: adjust the state of SAM elements and negative pressure intensity in real time;

[0072] The control subsystem is the "brain" of the entire plugging system. It is responsible for receiving data from temperature and pressure sensors and dynamically adjusting the deformation of the SMA element and the suction of the negative pressure device according to the set algorithm. It includes:

[0073] Microprocessor (such as ARM, FPGA): responsible for receiving and processing data from sensors and making decisions;

[0074] Control algorithm: Use PID control algorithm to adjust the deformation of SMA components and the working intensity of negative pressure device in real time according to temperature and pressure changes;

[0075] Communication interface: realize the communication between the system and external devices, and can be remotely monitored and operated through wireless or wired networks;

[0076] Based on the feedback of real-time data, the control subsystem intelligently adjusts the working status of the SMA element and the negative pressure device, making the plugging operation more precise and intelligent, and improving the flexibility and success rate of traditional pressure plugging technology.

[0077] Before plugging the leak, the status of the pipeline is monitored by pressure and temperature sensors inside and outside the pipeline to accurately locate the leak point. According to the characteristics of the SMA material, the temperature near the leak point is pre-adjusted to make the SMA element enter its optimal working state. In the present invention, the shape memory alloy is SAM.

[0078] S2: SMA element sealing pressure adjustment, building the SMA sealing pressure control function;

[0079] The working principle of the SMA element is: when the temperature of the pipeline changes, the SMA element will automatically deform according to the temperature change and adjust the sealing pressure in real time. Specifically, when the temperature of the pipeline increases, the SMA element contracts and increases the sealing pressure. When the temperature of the pipeline decreases, the SMA element expands and reduces the sealing pressure.

[0080] The sealing pressure control function of SMA is as follows:

[0081]

[0082] Among them, P seal (T,P pipe ,t) Sealing pressure calculated based on SMA adaptive sealing control, T is the real-time temperature of the pipeline, T0 is the phase change temperature of SMA, P pipe is the pressure difference between the inside and outside of the pipeline, t is the time, α and β are the influence coefficients of temperature change on alloy deformation and pressure attenuation, γ and δ represent the influence intensity of time and pressure on the sealing effect, ζ and ω are oscillation factors, which are used to simulate the dynamic response of the alloy under load.

[0083] The sealing pressure control function based on SMA takes into account the influence of temperature change on the sealing pressure, and introduces the pressure difference between the inside and outside of the pipeline, time effect and oscillation term of dynamic response.

[0084] The initial sealing pressure threshold P is set in the output result of the sealing pressure control function of SMA. seal，init ,

[0085] Critical sealing pressure threshold P seal，crit and safety sealing pressure threshold P seal，safe ;

[0086] Based on the thresholds set above, the following judgment process is used to ensure that the plugging method is always in a reasonable working state;

[0087] Initialization check: Calculate the initial sealing pressure P seal (T,P pipe , t=0), if P seal <P seal，init , start the temperature control system and adjust the response characteristics of the SMA until the sealing pressure reaches P seal，init ;

[0088] Dynamic adjustment and monitoring:

[0089] During the pipeline operation, the sealing pressure is monitored regularly and the pressure difference P between the inside and outside of the pipeline is calculated based on the real-time temperature T and the pressure difference P between the inside and outside of the pipeline. pipe , the sealing pressure is automatically adjusted through the temperature response characteristics of SMA;

[0090] If Pseal (T,P pipe ,t)<P seal，crit , triggering an alarm and starting heating or adjusting the sealing system to restore the sealing effect;

[0091] If P seal (T,P pipe ,t)>P seal，safe , by reducing the pressure in the pipeline or adjusting the response of the sealing material through the automatic control subsystem to avoid system overload;

[0092] Long-term operation monitoring:

[0093] During long-term operation, the sealing pressure P is continuously monitored. seal changes, especially when there are dramatic changes in temperature or pressure;

[0094] If the sealing pressure is lower than P for a long time seal，init or higher than P seal，safe , automatically enters the system maintenance mode to check whether the system is faulty or needs to replace the SMA component.

[0095] S3: Negative pressure adsorption coordinated control;

[0096] S31: Use a micro vacuum pump and a pressure sensor to establish a local negative pressure environment. When plugging a leak, the sensor monitors the pressure change in the pipeline in real time. The negative pressure pump absorbs the leaking medium in the pipeline and guides it to flow to a designated path.

[0097] S32: Combined with the pipeline pressure information fed back by the pressure sensor, the suction force of the micro vacuum pump is automatically adjusted to construct a residual pressure balance calculation formula to maintain a moderate negative pressure environment, prevent the residual pressure in the pipeline from causing recoil on the seal, and ensure the stability of the sealing area;

[0098] The residual pressure balance calculation formula is as follows:

[0099]

[0100] Among them, P residual (t) is the residual pressure in the pipeline at a certain moment.

[0101] Through the design of the residual pressure balance formula, the residual pressure in the pipeline and the impact of negative pressure adsorption can be calculated to reduce the impact of the pressure in the pipeline on the sealing material.

[0102] The negative pressure adsorption control formula is constructed according to the output result of the residual pressure balance calculation formula, and the negative pressure adsorption control formula is as follows:

[0103]

[0104] Among them, P seal,adj(t) is the sealing pressure after negative pressure adsorption adjustment, ι is the amplitude of negative pressure adjustment, It is the adjustment frequency of the negative pressure adsorption system.

[0105] Interactive judgment is performed based on the output result of the negative pressure adsorption control formula and the output result of the sealing pressure control function of the SMA;

[0106] If P seal,adj (t)<P seal，init or P seal,adj (t)<P seal，crit , it means that the sealing pressure is insufficient and it is necessary to adjust the negative pressure adsorption system or the response of the shape memory alloy to enhance the sealing effect;

[0107] If P seal,adj (t)>P seal，safe , it means that the sealing pressure is too high, and it is necessary to reduce the negative pressure adsorption strength or adjust the working state of the shape memory alloy to reduce the sealing pressure;

[0108] If P seal,adj (t) If the fluctuation is too large within a certain period of time, it means that the sealing system is unstable. This is caused by the imbalance between the negative pressure adsorption system and the shape memory alloy response, and the adjustment mechanism needs to be further optimized.

[0109] S33: The negative pressure and the action timing of the SMA sealing element are precisely adjusted through the control subsystem. For example, when the negative pressure adsorption begins, the SMA element adjusts the sealing pressure according to the preset temperature change curve to ensure that the sealing layer can remain stable under the residual pressure and recoil.

[0110] S4: System adaptive adjustment and feedback;

[0111] S41, adaptive feedback mechanism: the temperature sensor and pressure sensor feed back the real-time monitoring data to the control subsystem, and the control subsystem automatically adjusts the deformation of the SMA element and the intensity of negative pressure adsorption according to the feedback;

[0112] S42. Use neural networks to analyze and optimize the plugging process in real time, and adjust the operating parameters of the SMA sealing element and the negative pressure pump to adapt them to different pipeline working conditions and leakage levels.

[0113] S5: Leakage plugging effect evaluation, periodic self-inspection and adjustment;

[0114] S51: monitor the pressure change of the pipeline after plugging through the sensor to evaluate the stability of the plugging effect. After sealing, if the pressure fluctuation is within the predetermined range, it means that the sealing effect is good;

[0115] S52: After the plugging operation is completed, the system will perform self-inspection regularly to check the deformation state of the SMA element and the stability of the negative pressure environment to ensure that a good sealing effect can be maintained during long-term operation.

[0116] During use, by combining shape memory alloy (SMA) elements with miniature vacuum pumps, and utilizing adaptive sealing pressure control and negative pressure adsorption synergistic technology, precise adjustment of the pipeline sealing system can be achieved. This method has a wide range of application scenarios, especially in the petrochemical industry, high-pressure gas transportation and other fields. It can effectively repair pipeline leaks without affecting the normal operation of the pipeline.

[0117] Embodiment 2

[0118] Referring to Tables 1-3, which are the second embodiment of the present invention, this embodiment is different from the first embodiment in that, in order to verify its beneficial effects, experimental comparison data between the present invention and the prior art are provided.

[0119] This example aims to evaluate the effectiveness of the pressure plugging method for petrochemical pipelines based on SMA elements and micro vacuum pumps, and compare it with the existing traditional plugging methods. The main goal of the experiment is to verify the advantages of the proposed plugging method in terms of sealing effect, stability, and coping with pipeline pressure fluctuations.

[0120] Equipment and materials required for the experiment:

[0121] Petrochemical pipelines (500 mm in diameter, made of carbon steel) were used to simulate leakage scenarios;

[0122] SMA sealing element: a specific shape memory alloy element with a low phase transition temperature, embedded in the sealing structure of the pipeline;

[0123] Micro vacuum pump: An efficient micro pump used to create a negative pressure environment and accurately adjust the pressure difference between the inside and outside of the pipeline;

[0124] Sensors: including temperature sensors, pressure sensors and control subsystem interfaces, used to monitor pipeline temperature and pressure in real time and provide feedback to the control subsystem;

[0125] Control subsystem: A real-time adjustment system designed based on an embedded microcontroller that automatically adjusts the deformation and negative pressure adsorption strength of the SMA element.

[0126] Experimental steps:

[0127] 1. Embed the SMA sealing element into the sealing structure of the pipeline and install the micro vacuum pump and pressure sensor;

[0128] 2. Apply a constant pressure load in the pipeline, and adjust the deformation of the SMA element through the control subsystem. Use a temperature sensor to monitor the pipeline temperature, and a pressure sensor to feedback pressure change information in real time.

[0129] 3. Use a micro vacuum pump combined with pressure sensor feedback to adjust suction in real time, create a local negative pressure environment to balance the pressure difference inside and outside the pipeline, and accurately calculate the negative pressure amplitude that needs to be adjusted through the residual pressure balance calculation formula;

[0130] 4. Based on the feedback from the sensor, the system automatically adjusts the state of the SMA element and the suction force of the micro vacuum pump. The neural network analyzes the changes in the plugging process and optimizes the operating parameters in real time.

[0131] 5. Continuously monitor pipeline pressure fluctuations, evaluate the stability of the sealing effect, and perform regular self-inspections after the leak is plugged.

[0132] The experimental data are recorded in the following three tables.

[0133] Table 1: Comparison of plugging effects

[0134]

[0135] Table 2: Temperature and pressure regulation comparison table

[0136]

[0137] Table 3: Long-term stability and self-test data table

[0138]

[0139] In Table 1, it can be seen that the sealing pressure of the present invention is significantly improved compared with the traditional technology. For example, in Experiment No. 1, the sealing pressure of the traditional technology is 800Pa, while the sealing pressure of the present invention reaches 950Pa. As the experiment progresses, the sealing pressure of the present invention is maintained more stably, the leakage rate is lower, the reaction time is shorter, and the pressure fluctuation amplitude is smaller, indicating that the present invention has obvious advantages in sealing effect;

[0140] In Table 2, it can be seen that compared with the traditional technology, the technology of the present invention can more accurately adjust the sealing pressure under different environmental conditions, effectively cope with temperature and pressure fluctuations, and maintain a more stable sealing effect;

[0141] In Table 3, during the long-term operation of the present invention, the change in sealing pressure is small, the system self-test results are all qualified, and the stability score is also high. Compared with traditional technologies, the present invention shows higher stability in long-term operation, can automatically adjust the sealing pressure, and ensure that the system continues to work effectively.

[0142] In summary, the present invention shows significant advantages in sealing effect, temperature and pressure regulation, long-term stability, etc. Compared with traditional technologies, the present invention can not only adjust the sealing pressure more accurately, but also better adapt to temperature changes and the pressure difference between the inside and outside of the pipeline, thereby ensuring the efficient and stable operation of the sealing system.

[0143] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for plugging leaks in a petrochemical pipeline under pressure, characterized in that: include: S1: Construction of a leak plugging system using shape memory alloy elements and micro vacuum pumps; S2: SMA element sealing pressure adjustment, building the SMA sealing pressure control function; S3: Negative pressure adsorption coordinated control; S4: System adaptive adjustment and feedback; S5: Evaluation of leak plugging effect, periodic self-inspection and adjustment.

2. A method for plugging leaks in a petrochemical pipeline under pressure according to claim 1, characterized in that: The sealing pressure control function of the SMA is as follows: Among them, P seal (T,P pipe ,t) Sealing pressure calculated based on SMA adaptive sealing control, T is the real-time temperature of the pipeline, T0 is the phase change temperature of SMA, P pipe is the pressure difference between the inside and outside of the pipeline, t is the time, α and β are the influence coefficients of temperature change on alloy deformation and pressure attenuation, γ and δ represent the influence intensity of time and pressure on the sealing effect, ζ and ω are oscillation factors, which are used to simulate the dynamic response of the alloy under load.

3. A method for plugging leaks in a petrochemical pipeline under pressure according to claim 2, characterized in that: The initial sealing pressure threshold P is set in the output result of the sealing pressure control function of SMA. seal，init , critical sealing pressure threshold P seal，crit and safety sealing pressure threshold P seal，safe ; Based on the thresholds set above, the following judgment process is used to ensure that the plugging method is always in a reasonable working state; Initialization check: Calculate the initial sealing pressure P seal (T,P pipe , t=0), if P seal <P seal，init , start the temperature control system and adjust the response characteristics of the SMA until the sealing pressure reaches P seal，init ; Dynamic adjustment and monitoring: During the pipeline operation, the sealing pressure is monitored regularly and the pressure difference P between the inside and outside of the pipeline is calculated based on the real-time temperature T and the pressure difference P between the inside and outside of the pipeline. pipe , the sealing pressure is automatically adjusted through the temperature response characteristics of SMA; If P seal (T,P pipe ,t)<P seal，crit , triggering an alarm and starting heating or adjusting the sealing system to restore the sealing effect; If P seal (T,P pipe ,t)>P seal，safe , by reducing the pressure in the pipeline or adjusting the response of the sealing material through the automatic control subsystem to avoid system overload; Long-term operation monitoring: During long-term operation, the sealing pressure P is continuously monitored. seal changes, especially when there are dramatic changes in temperature or pressure; If the sealing pressure is lower than P for a long time seal，init or higher than P seal，safe , automatically enters the system maintenance mode to check whether the system is faulty or needs to replace the SMA component.

4. A method for plugging leaks in a petrochemical pipeline under pressure according to claim 1, characterized in that: The negative pressure adsorption coordinated control is achieved by the following steps: S31: Use a micro vacuum pump and a pressure sensor to establish a local negative pressure environment. When plugging a leak, the sensor monitors the pressure changes in the pipeline in real time. S32: Combined with the pipeline pressure information fed back by the pressure sensor, the suction force of the micro vacuum pump is automatically adjusted to construct a residual pressure balance calculation formula; S33: Through the control subsystem, the negative pressure and the action timing of the SMA sealing element are precisely adjusted.

5. A method for plugging leaks in a petrochemical pipeline under pressure according to claim 4, characterized in that: The residual pressure balance calculation formula is as follows: Among them, P residual (t) is the residual pressure in the pipeline at a certain moment.

6. A method for plugging leaks in a petrochemical pipeline under pressure according to claim 5, characterized in that: The negative pressure adsorption control formula is constructed according to the output result of the residual pressure balance calculation formula, and the negative pressure adsorption control formula is as follows: Among them, P seal,adj (t) is the sealing pressure after negative pressure adsorption adjustment, ι is the amplitude of negative pressure adjustment, It is the adjustment frequency of the negative pressure adsorption system.

7. A method for plugging leaks in a petrochemical pipeline under pressure according to claim 6, characterized in that: Interactive judgment is performed based on the output result of the negative pressure adsorption control formula and the output result of the sealing pressure control function of the SMA; If P seal,adj (t)<P seal，init or P seal,adj (t)<P seal，crit , it means that the sealing pressure is insufficient and it is necessary to adjust the negative pressure adsorption system or the response of the shape memory alloy to enhance the sealing effect; If P seal,adj (t)>P seal，safe , it means that the sealing pressure is too high, and it is necessary to reduce the negative pressure adsorption strength or adjust the working state of the shape memory alloy to reduce the sealing pressure; If P seal,adj (t) If the fluctuation is too large within a certain period of time, it means that the sealing system is unstable. This is caused by the imbalance between the negative pressure adsorption system and the shape memory alloy response, and the adjustment mechanism needs to be further optimized.

8. A method for plugging leaks in a petrochemical pipeline under pressure according to claim 1, characterized in that: The plugging system comprises: SAM sealing element: embedded in the pipeline sealing structure, adjusting the sealing pressure through temperature changes; Negative pressure regulating device: A micro vacuum pump is used in conjunction with a pressure sensor to create a local negative pressure environment when plugging leaks, thereby offsetting the effect of residual pressure in the pipeline on the seal; Temperature and pressure sensors: used to monitor the temperature and pressure of the pipeline in real time and provide feedback to the control subsystem; Control subsystem: adjust the state and negative pressure intensity of the SAM element in real time.

9. A method for plugging leaks in a petrochemical pipeline under pressure according to claim 8, characterized in that: The system adaptive adjustment and feedback are achieved through the following steps: S41, adaptive feedback mechanism: the temperature sensor and pressure sensor feed back the real-time monitoring data to the control subsystem, and the control subsystem automatically adjusts the deformation of the SMA element and the intensity of negative pressure adsorption according to the feedback; S42. Use neural networks to analyze and optimize the plugging process in real time, and adjust the operating parameters of the SMA sealing element and the negative pressure pump to adapt them to different pipeline working conditions and leakage levels.

10. A method for plugging leaks in a petrochemical pipeline under pressure according to claim 1, characterized in that: The S5 comprises the following steps: S51: monitor the pressure change of the pipeline after plugging through the sensor to evaluate the stability of the plugging effect. After sealing, if the pressure fluctuation is within the predetermined range, it means that the sealing effect is good; S52: After the plugging operation is completed, the system will perform self-inspection regularly to check the deformation state of the SMA element and the stability of the negative pressure environment to ensure that a good sealing effect can be maintained during long-term operation.

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