Nuclear power pipeline defect on-line monitoring system

Abstract

The invention provides a nuclear power pipeline defect on-line monitoring system. The nuclear power pipeline defect on-line monitoring system comprises a wall thickness monitoring sensor, a crack monitoring sensor, a data acquisition device and a server, the data acquisition device is in wired connection with the wall thickness monitoring sensor and the crack monitoring sensor, and is used for acquiring wall thickness monitoring data and crack monitoring data of a to-be-monitored pipeline monitoring area and transmitting the data to the server; and the server is in communication connection with the data acquisition device and is used for calculating the monitoring condition of the monitoring area according to the wall thickness monitoring data and the crack monitoring data and outputting a monitoring result. Wireless transmission is replaced by a wired connection mode, and the data acquisition device is in wired connection with the wall thickness monitoring sensor and the crack monitoring sensor, so that interference of the radiation environment of the nuclear power plant on wireless signals is effectively avoided.

Description

Technical Field

[0001] The present invention relates to nuclear power pipeline detection technology, and more particularly to an online monitoring system for nuclear power pipeline defects. Background Art

[0002] Nuclear power pipelines are often exposed to radiation, making conventional monitoring sensors difficult to use. Existing solutions that integrate data acquisition with sensors and utilize wireless transmission have limitations. In the unique environment of nuclear power plants, this approach can cause radiation interference with wireless signals. High-energy radiation can damage the electronic components of wireless communication modules, shortening equipment lifespan and increasing maintenance costs. This makes it difficult to meet the high safety and reliability requirements of nuclear power plants for monitoring systems. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide an online monitoring system for nuclear power pipeline defects in view of the defects of the high radiation environment of nuclear power plants in the prior art.

[0004] The technical solution adopted by the present invention to solve the technical problem is: constructing an online monitoring system for nuclear power pipeline defects, including a wall thickness monitoring sensor, a crack monitoring sensor, a data acquisition device and a server;

[0005] The data acquisition device is connected to the wall thickness monitoring sensor and the crack monitoring sensor by wires, respectively, and is used to collect wall thickness monitoring data of the monitored area of the pipeline to be tested and crack monitoring data of the monitored area of the pipeline to be tested, and transmit the data to the server;

[0006] The server is in communication with the data acquisition device and is used to calculate the monitoring situation of the monitoring area according to the wall thickness monitoring data and the crack monitoring data, and output the monitoring results.

[0007] In one embodiment, the server includes:

[0008] A database unit, used for storing the wall thickness monitoring data and the crack monitoring data;

[0009] a wall thickness calculation unit, configured to calculate a wall thickness monitoring result based on the wall thickness monitoring data;

[0010] A crack calculation unit is used to calculate a crack monitoring result based on the crack monitoring data.

[0011] In one embodiment, the wall thickness monitoring data includes ultrasonic echo time difference and ultrasonic sound velocity, and the wall thickness calculation unit includes:

[0012] a wall thickness calculation module, configured to calculate the wall thickness monitoring result of the monitoring area according to the ultrasonic echo time difference and the ultrasonic sound speed;

[0013] The corrosion rate calculation module is used to calculate the wall thickness change gradient of the monitoring area according to multiple wall thickness monitoring results in time series, and eliminate noise interference through a filtering algorithm to obtain the corrosion rate of the monitoring area.

[0014] In one embodiment, the crack monitoring data includes the arrival time difference of the guided wave reflection signal, the reflected wave envelope width and the guided wave mode conversion energy ratio, and the crack calculation unit includes:

[0015] A crack location calculation module, configured to calculate the crack location in the monitoring area based on the arrival time difference of the guided wave reflection signal;

[0016] a crack length calculation module, configured to determine the crack length at the crack location according to the reflected wave envelope width;

[0017] A crack depth calculation module is used to determine the crack depth at the crack position according to the guided wave mode conversion energy ratio.

[0018] In one embodiment, the database unit further stores attribute data of the pipeline to be tested; and the server further includes:

[0019] A safety assessment unit, configured to substitute the property data of the pipeline to be tested and the wall thickness monitoring result into a preset stress formula to calculate an actual stress value of the pipeline to be tested;

[0020] and judging whether the pipeline to be tested is safe based on the actual stress value and a preset reasonable stress value range;

[0021] Wherein, the preset stress formula includes:

[0022]

[0023] Where S SL is the actual stress value, P is the design pressure of the pipeline, D0 is the outer diameter of the pipeline, t current is the wall thickness monitoring result, M A Resultant moment, Z is the section modulus, and i is the stress intensification factor.

[0024] In one embodiment, the database unit further stores the corrosion rate and / or the average annual crack growth rate, and the server further includes:

[0025] a remaining life evaluation unit, configured to calculate based on the corrosion rate and the wall thickness monitoring result to obtain a wall thickness-related remaining life;

[0026] And / or, the crack-related remaining life is obtained by performing calculation based on the average annual growth rate of the storage crack and the crack length and / or the crack depth of the pipeline to be tested.

[0027] In one embodiment, the calculating based on the wall thickness variation data and the wall thickness monitoring result to obtain the wall thickness-related remaining life includes:

[0028] Multiple iterative calculations are performed based on the wall thickness monitoring results and the corrosion rate until the calculated actual stress value does not meet the preset reasonable stress value range, thereby obtaining the wall thickness-related remaining life.

[0029] In one embodiment, the remaining life assessment unit is further configured to calculate an equivalent corrected wall thickness based on the wall thickness monitoring result and the crack depth;

[0030] Substituting the equivalent corrected wall thickness into the preset stress formula to obtain the remaining life of the equivalent corrected wall thickness;

[0031] The minimum value is taken according to the remaining life of the equivalent corrected wall thickness and the remaining life related to the crack to obtain the comprehensive remaining life of the pipeline to be tested.

[0032] In one embodiment, the server further includes:

[0033] An early warning unit is used to perform early warning evaluation based on different preset thresholds corresponding to the wall thickness monitoring results, and / or the crack monitoring results, and / or the wall thickness-related remaining life, and / or the crack-related remaining life, and / or the comprehensive remaining life, and output early warning evaluation information.

[0034] In one embodiment, at least two wall thickness monitoring sensors are arranged at a bend position of the pipeline to be measured, and the crack monitoring sensor is arranged on a side of the wall thickness monitoring sensor away from the bend position of the pipeline to be measured.

[0035] The beneficial effect of the present invention is that the present invention provides an online monitoring system for nuclear power pipeline defects, which includes a wall thickness monitoring sensor, a crack monitoring sensor, a data acquisition device and a server; the data acquisition device is respectively connected to the wall thickness monitoring sensor and the crack monitoring sensor by wire, and is used to collect wall thickness monitoring data of the monitoring area of the pipeline to be tested and crack monitoring data of the monitoring area of the pipeline to be tested, and transmit them to the server; the server is communicatively connected to the data acquisition device, and is used to calculate the monitoring status of the monitoring area based on the wall thickness monitoring data and the crack monitoring data, and output the monitoring results.

[0036] The present invention has the beneficial effects of providing an online monitoring system for nuclear power pipeline defects, comprising a wall thickness monitoring sensor, a crack monitoring sensor, a data acquisition device, and a server. The data acquisition device is wiredly connected to the wall thickness monitoring sensor and the crack monitoring sensor, respectively, for collecting wall thickness monitoring data and crack monitoring data from the monitored area of the pipeline to be tested, and transmitting the data to the server. The server is communicatively connected to the data acquisition device, for calculating the monitoring status of the monitored area based on the wall thickness monitoring data and the crack monitoring data, and outputting the monitoring results. By adopting a wired connection instead of wireless transmission, the present invention connects the data acquisition device to the wall thickness monitoring sensor and the crack monitoring sensor, respectively, thereby effectively avoiding interference with wireless signals from the nuclear power plant's radiation environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0038] Figure 1 This is a logic diagram of the online monitoring system for nuclear power pipeline defects of the present invention;

[0039] Figure 2 It is a schematic structural diagram of the crack monitoring sensor and the wall thickness monitoring sensor of the present invention;

[0040] Figure 3 It is a structural diagram of the data acquisition device of the present invention;

[0041] Figure 4 It is a structural schematic diagram of the online monitoring system for nuclear power pipeline defects of the present invention.

[0042] The components are as follows:

[0043] 10. Crack monitoring sensor; 20. Wall thickness monitoring sensor; 30. Data acquisition device; 31. Ultrasonic wall thickness monitoring sensor transmitter; 32. Guided wave crack monitoring sensor transmitter; 33. Signal adapter board; 34. Ground terminal; 35. Wiring terminal; 40. Server; 50. Pipeline to be tested; 60. Display screen; 70. Power module. DETAILED DESCRIPTION

[0044] The present application is further described in detail below by means of specific embodiments in conjunction with the accompanying drawings. Similar elements in different embodiments are numbered with associated similar elements. In the following embodiments, many detailed descriptions are provided to enable the present application to be better understood. However, those skilled in the art will readily appreciate that some of the features may be omitted in different circumstances, or may be replaced by other elements, materials, or methods. In some cases, some operations related to the present application are not shown or described in the specification. This is to avoid the core portion of the present application being overwhelmed by excessive descriptions. For those skilled in the art, it is not necessary to describe these related operations in detail. They can fully understand the related operations based on the description in the specification and the general technical knowledge in the art.

[0045] like Figure 1 As shown, Figure 1 The figure is a logic diagram of the online monitoring system for nuclear power pipeline defects of the present invention.

[0046] The technical solution adopted by the present invention to solve the technical problem is: constructing an online monitoring system for nuclear power pipeline defects, including a wall thickness monitoring sensor 20, a crack monitoring sensor 10, a data acquisition device 30 and a server 40;

[0047] The data acquisition device 30 is connected to the wall thickness monitoring sensor 20 and the crack monitoring sensor 10 by wires, and is used to collect the wall thickness monitoring data and the crack monitoring data of the monitoring area of the pipeline 50 to be tested, and transmit them to the server 40;

[0048] The server 40 is in communication with the data acquisition device 30 and is used to calculate the monitoring situation of the monitoring area based on the wall thickness monitoring data and the crack monitoring data and output the monitoring results.

[0049] like Figure 2 As shown, in one embodiment, monitoring nodes are installed in high-risk sections of the pipeline (such as elbows and welds). Each node contains at least two ultrasonic wall thickness monitoring sensors 20 and one set of annular magnetostrictive guided wave crack monitoring sensors 10. The ultrasonic wall thickness monitoring sensors 20 use a pulse reflection method to automatically and regularly measure the pipeline wall thickness, calculate the corrosion depth through time difference, and support adaptive transmission frequency adjustment to accommodate different pipe materials and corrosion conditions. The guided wave crack monitoring sensor 10 is used to excite torsional mode guided waves (T waves) that propagate circumferentially along the pipeline, regularly collect data, identify the location and size of circumferential cracks through the energy attenuation of the received signal and the characteristics of the reflected wave, and use a dispersion compensation algorithm to eliminate the impact of pipeline material inhomogeneity on the detection results.

[0050] The data acquisition device 30 is connected to the wall thickness monitoring sensor 20 and the crack monitoring sensor 10 by wires, respectively, to collect wall thickness monitoring data and crack monitoring data from the monitored area of the pipeline 50 under test. The data acquisition device 30 is internally equipped with a guided wave sensor transmitter and an electromagnetic ultrasonic sensor transmitter, which transmit the collected data to the server cabinet 40. The wall thickness monitoring sensor 20 and the crack monitoring sensor 10 are located in a radiation area, while the data acquisition device 30 is located in a non-radiation area. This effectively addresses the issue of sensor failure caused by nuclear power radiation environments.

[0051] like Figure 3 As shown, in one embodiment, the data acquisition device 30 includes an ultrasonic wall thickness monitoring sensor transmitter 31 and a guided wave crack monitoring sensor transmitter 32, a signal adapter board 33, a ground terminal 34, and a terminal 35. There are four ultrasonic wall thickness monitoring sensor transmitters 31 and one guided wave crack monitoring sensor transmitter 32. The ultrasonic wall thickness monitoring sensor transmitter 31 and the guided wave crack monitoring sensor transmitter 32 respectively collect pipeline wall thickness data and crack data, convert these data into electrical signals, and transmit them to the data acquisition device 30 after preliminary processing. The signal adapter board 33 is used to aggregate and transfer signals from multiple transmitters to ensure that these signals can be effectively transmitted to the subsequent processing units of the data acquisition device, thereby ensuring the integrity and accuracy of the data. The ground terminal 34 provides a stable grounding connection for the entire data acquisition device 30, ensuring the electrical safety of the device during operation, while reducing the impact of electromagnetic interference on the signal and improving the stability of the signal. The terminal 35 provides a convenient wiring interface for electrically connecting the wall thickness monitoring sensor, the crack monitoring sensor and the data acquisition device 30 with other external devices (such as a server, etc.), thereby ensuring the connectivity and stability of the entire monitoring system.

[0052] like Figure 4 As shown, the server 40 cabinet houses a power distribution unit, a data processing unit, an evaluation computer, a display screen 60, and a power module 70. The power module powers the online monitoring system, including the on-site sensors, the data acquisition device 30, and the server 40 cabinet. The data processing unit processes the signals transmitted by the data acquisition device 30. The evaluation computer also houses a pipeline database and an intelligent pipeline defect analysis module. The pipeline database primarily stores parameter information for the monitored pipelines and routinely measured pipeline defect data, providing a data foundation for aging management and routine maintenance. The intelligent pipeline defect analysis module implements functions such as sensor data analysis, statistics, and alarm indication.

[0053] Based on the received wall thickness and crack monitoring data, the evaluation computer calculates the monitoring status of the monitored area and outputs the monitoring results. Specifically, it extracts the wall thickness change rate from the ultrasonic data, and the crack length, depth, and location from the guided wave data. Using relevant parameters and data from the pipeline database, combined with pre-set calculation models and evaluation criteria, it conducts a comprehensive assessment of the pipeline's health, predicts pipeline lifespan, and triggers graded alarms based on pre-set thresholds.

[0054] The data is transmitted to the office via the nuclear power plant's internal LAN and supports multi-terminal access, so that staff can understand the health status of the pipeline in a timely manner and provide a basis for maintenance decisions.

[0055] Furthermore, the server 40 includes:

[0056] Database unit, used to store wall thickness monitoring data and crack monitoring data;

[0057] A wall thickness calculation unit, used to calculate the wall thickness monitoring results based on the wall thickness monitoring data;

[0058] The crack calculation unit is used to calculate the crack monitoring result based on the crack monitoring data.

[0059] In one embodiment, the database unit primarily stores wall thickness monitoring data and crack monitoring data. This data includes not only real-time monitoring data but also historical monitoring data, facilitating comparative analysis and trend prediction. The database unit also stores basic information about nuclear power pipelines, such as pipeline material, specifications, installation location, and service life, providing foundational data for subsequent calculations and assessments. The wall thickness calculation unit calculates wall thickness monitoring results based on the wall thickness monitoring data. Its core approach is to utilize a specific algorithm model, based on the principle of ultrasonic pulse reflection and incorporating parameters such as the speed of sound of the pipeline material, to accurately calculate the actual wall thickness of the pipeline. This calculation result not only reflects the current specific value of the pipeline wall thickness but can also be compared with historical wall thickness data to analyze wall thickness trends, providing a key basis for assessing the extent of pipeline corrosion. The crack calculation unit analyzes and processes the crack monitoring data to calculate the crack monitoring results. By extracting and analyzing guided wave signal features, such as signal energy attenuation, frequency variation, and phase shift, and combining them with the scattering and reflection characteristics of the guided wave at the crack, geometric parameters such as crack location, length, and depth are determined. These calculation results are crucial for timely detection and assessment of pipeline crack damage.

[0060] Server 40 comprehensively analyzes the collected wall thickness monitoring data and crack monitoring data, calculates the overall monitoring status of the monitoring area, and generates corresponding monitoring results. These monitoring results are output in the form of charts, reports, etc., which intuitively display the health status of the pipeline and provide decision support for maintenance personnel.

[0061] Furthermore, the wall thickness monitoring data includes ultrasonic echo time difference and ultrasonic sound velocity, and the wall thickness calculation unit includes:

[0062] The wall thickness calculation module is used to calculate the wall thickness monitoring results of the monitoring area based on the ultrasonic echo time difference and ultrasonic sound speed;

[0063] The corrosion rate calculation module is used to calculate the wall thickness change gradient of the monitoring area according to multiple wall thickness monitoring results in time series, and eliminate noise interference through a filtering algorithm to obtain the corrosion rate of the monitoring area.

[0064] In one embodiment, the wall thickness monitoring data includes ultrasonic echo time difference and ultrasonic sound velocity. The wall thickness calculation unit includes a wall thickness calculation module for calculating the wall thickness monitoring results of the monitoring area based on the ultrasonic echo time difference and ultrasonic sound velocity, and a corrosion rate calculation module for calculating the wall thickness change gradient of the monitoring area based on multiple wall thickness monitoring results in a time series, and removing noise interference through a filtering algorithm to obtain the corrosion rate of the monitoring area.

[0065] The wall thickness calculation module uses the principle of ultrasonic pulse reflection, combined with parameters such as the speed of sound of the pipe material, to calculate the actual wall thickness of the pipe. This calculation result not only reflects the specific value of the current pipe wall thickness, but also can be compared with historical wall thickness data to analyze the trend of wall thickness changes, thus providing a key basis for evaluating the degree of corrosion of the pipe. As an option, according to the ultrasonic echo time difference formula:

[0066]

[0067] Where V is the speed of sound, d is the wall thickness, and the temperature compensation model is used to correct the speed of sound deviation to obtain the wall thickness monitoring result.

[0068] The corrosion rate calculation module calculates the gradient of wall thickness change over time based on multiple time series wall thickness monitoring results. After removing noise interference through a filtering algorithm, a relatively accurate corrosion rate is obtained. This result is important for predicting the remaining life of the pipeline and formulating maintenance plans. Alternatively, the wall thickness change gradient: Where Δt is the time change and Δd is the wall thickness change. The corrosion rate is obtained by removing noise interference through filtering algorithm.

[0069] The crack calculation unit focuses on analyzing and processing crack monitoring data and calculating crack monitoring results. By extracting and analyzing guided wave signal characteristics, such as signal energy attenuation, frequency variation, and phase shift, combined with the scattering and reflection properties of guided waves at the crack site, it determines geometric parameters such as the crack's location, length, and depth. These calculation results are crucial for timely detection and assessment of pipeline crack damage.

[0070] Furthermore, the crack monitoring data includes the arrival time difference of the guided wave reflection signal, the reflection wave envelope width and the guided wave mode conversion energy ratio. The crack calculation unit includes:

[0071] Crack location calculation module, used to calculate the crack location in the monitoring area based on the arrival time difference of the guided wave reflection signal;

[0072] A crack length calculation module is used to determine the crack length at the crack location based on the reflected wave envelope width;

[0073] The crack depth calculation module is used to determine the crack depth at the crack position according to the guided wave mode conversion energy ratio.

[0074] In one embodiment, the crack location calculation module calculates the crack location based on the arrival time difference of the guided wave reflection signal using the formula L = (v * Δt) / 2, where v is the guided wave velocity and Δt is the arrival time difference of the guided wave reflection signal. By accurately measuring the time difference of the guided wave reflection signal and combining it with the propagation velocity of the guided wave in the pipeline, the specific axial position of the crack in the pipeline can be determined.

[0075] The crack length calculation module determines crack length based on the reflected wave envelope width. Through extensive experimental data and theoretical analysis, an empirical relationship between reflected wave envelope width and crack length has been established. In actual monitoring, the approximate crack length can be determined by measuring the reflected wave envelope width and applying this established relationship.

[0076] The crack depth calculation module uses the guided wave modal conversion energy ratio to determine crack depth. When a guided wave encounters a crack, a modal conversion occurs, and guided waves of different modes have different energy distributions. By analyzing the energy ratio changes before and after modal conversion, combined with experimental data and theoretical models, the crack depth can be inferred.

[0077] Server 40 comprehensively analyzes the collected wall thickness monitoring data and crack monitoring data, calculates the overall monitoring status of the monitoring area, and generates corresponding monitoring results. These monitoring results are output in the form of charts, reports, etc., which intuitively display the health status of the pipeline and provide decision support for maintenance personnel.

[0078] Furthermore, the database unit also stores attribute data of the pipeline 50 to be tested; the server 40 also includes:

[0079] A safety assessment unit, configured to substitute the property data of the pipeline to be tested and the wall thickness monitoring result into a preset stress formula to calculate the actual stress value of the pipeline to be tested 50;

[0080] And according to the actual stress value and the preset reasonable stress value range, determine whether the pipeline 50 to be tested is safe;

[0081] Among them, the preset stress formulas include:

[0082]

[0083] Where S SL is the actual stress value, P is the design pressure of the pipeline, D0 is the outer diameter of the pipeline, t current is the wall thickness monitoring result, M A Resultant moment, Z is the section modulus, and i is the stress intensification factor.

[0084] In one embodiment, the safety assessment unit is configured to substitute the pipeline attribute data and wall thickness monitoring results into a preset stress formula to calculate the actual stress value of the pipeline 50 under test. Based on the actual stress value and a preset reasonable stress value range, the safety of the pipeline 50 under test is determined. The calculated actual stress value is compared with the preset reasonable stress value range using the preset stress formula. If the actual stress value is within the reasonable range, the pipeline is deemed safe. If it is outside the reasonable range, a corresponding alarm is triggered, prompting maintenance personnel to take timely action.

[0085] Server 40 comprehensively analyzes the collected wall thickness and crack monitoring data, calculates the overall monitoring status of the monitored area, and generates corresponding monitoring results. These monitoring results are output in the form of charts, reports, etc., visually demonstrating the pipeline's health and providing decision support for maintenance personnel. The data is transmitted to the office via the nuclear power plant's internal local area network. Staff can access this data on multiple devices, conveniently monitoring the pipeline's status and promptly identifying potential problems.

[0086] Furthermore, the database unit also stores the corrosion rate and / or the average annual crack growth rate. The server 40 further includes:

[0087] Remaining life assessment unit, used to calculate the remaining life related to wall thickness based on the corrosion rate and wall thickness monitoring results;

[0088] And / or, the crack-related remaining life is calculated based on the average annual growth rate of the storage crack and the crack length and / or the crack depth of the pipeline 50 to be tested.

[0089] In one embodiment, the database unit stores wall thickness monitoring data, crack monitoring data, and property data of the pipeline under test 50, as well as key information such as corrosion rate and average annual crack growth rate. The wall thickness calculation unit includes a wall thickness calculation module and a corrosion rate calculation module. The wall thickness calculation module calculates real-time wall thickness based on the ultrasonic echo time difference and the speed of sound. The corrosion rate calculation module uses a filtering algorithm to remove noise interference from the time series wall thickness data to determine the corrosion rate. The crack calculation unit includes a crack location calculation module, a crack length calculation module, and a crack depth calculation module. The crack location calculation module determines the crack location based on the arrival time difference of the guided wave reflection signal. The crack length calculation module determines the crack length based on the empirical correspondence between the reflected wave envelope width and crack length. The crack depth calculation module determines the crack depth based on the relationship between the guided wave modal conversion energy ratio and crack depth. The safety assessment unit substitutes the pipeline property data and wall thickness monitoring results into a preset stress formula to calculate the actual pipeline stress value. This is then compared to a preset reasonable stress range to determine the pipeline's safety.

[0090] The remaining life assessment unit is one of the key parts of the system. It uses the formula:

[0091]

[0092] Calculate the wall thickness-dependent remaining life, where t future is the remaining life of the future wall thickness, t current is the current wall thickness, Δd is the change in wall thickness, Δt is the time change, and ΔT is a constant (usually 1 year). The pipeline stress change trend is calculated through multiple iterations to predict the remaining life of the pipeline due to corrosion thinning. At the same time, combined with the average annual crack growth rate and crack length and depth, the formula is used:

[0093]

[0094] Calculate the crack-related remaining life, where L C is the remaining life of the pipeline, a c is the critical crack size of the pipeline, a0 is the current crack size, and Δa is the average annual crack growth rate.

[0095] Furthermore, based on the wall thickness change data over time and the wall thickness monitoring results, the wall thickness-related remaining life is calculated, including:

[0096] Multiple iterative calculations are performed based on the wall thickness monitoring results and the corrosion rate until the calculated actual stress value does not meet the preset reasonable stress value range, and the wall thickness-related remaining life is obtained.

[0097] In one embodiment, the remaining life assessment unit performs multiple iterative calculations based on wall thickness monitoring results and corrosion rates to predict wall thinning trends. Each iteration updates the wall thickness value and calculates the actual stress until the actual stress exceeds a preset range. The time corresponding to this number of iterations is the wall thickness-related remaining life. The crack-related remaining life is also calculated by combining the average annual crack growth rate and crack size. In cases where corrosion and cracks coexist, the crack depth is considered a localized thinning, and the remaining life is comprehensively assessed.

[0098] Furthermore, the remaining life assessment unit is also used to calculate the equivalent corrected wall thickness based on the wall thickness monitoring result and the crack depth;

[0099] Substitute the equivalent corrected wall thickness into the preset stress formula to obtain the remaining life of the equivalent corrected wall thickness;

[0100] The minimum value is taken according to the equivalent corrected wall thickness remaining life and the crack-related remaining life to obtain the comprehensive remaining life of the pipeline 50 to be tested.

[0101] In one embodiment, the remaining life assessment unit performs multiple iterative calculations based on the corrosion rate and wall thickness monitoring results to predict the wall thickness thinning trend. Each iteration updates the wall thickness value and calculates the actual stress until the calculated actual stress value does not meet the preset reasonable stress value range. The time corresponding to the number of iterations at this time is the wall thickness-related remaining life. At the same time, the unit also uses the equivalent modified wall thickness formula based on the average annual crack growth rate and crack length and depth: eff =t current -a, where a is the crack depth, t eff is the equivalent corrected wall thickness, t current For the current wall thickness, use the preset stress formula:

[0102]

[0103] Calculate the crack-related remaining life. Where L remain is the remaining life, and β is the composite defect correction coefficient.

[0104] In addition, the remaining life assessment unit is also used to calculate the equivalent corrected wall thickness based on the wall thickness monitoring results and the crack depth, and substitute the equivalent corrected wall thickness into the preset stress formula to obtain the remaining life of the equivalent corrected wall thickness. Finally, according to the remaining life L of the equivalent corrected wall thickness t and crack-related residual life L c , taking the minimum value to obtain the comprehensive remaining life of the tested pipe 50. Alternatively, first, the stress calculation formula is used to calculate the remaining life of the pipe wall thickness based on the corrected wall thickness value. This is compared with the calculated crack life, and the minimum value is taken. Then, a composite defect correction coefficient β is introduced. The value of β is determined based on the finite element calculation results.

[0105] Furthermore, the server 40 further includes:

[0106] The early warning unit is used to perform early warning evaluation based on different preset thresholds corresponding to the wall thickness monitoring results, and / or crack monitoring results, and / or wall thickness related remaining life, and / or crack related remaining life, and / or comprehensive remaining life, and output early warning evaluation information.

[0107] In one embodiment, the early warning unit performs early warning assessments based on preset thresholds corresponding to indicators such as wall thickness monitoring results, crack monitoring results, wall thickness-related remaining life, crack-related remaining life, and comprehensive remaining life. For example, a level 1 alarm is triggered when the wall thickness decreases by more than 10% of the original thickness or the crack length exceeds 5mm; a level 2 alarm is triggered when the calculated remaining life is less than the maintenance period. The early warning unit compiles the assessment results into early warning assessment information and outputs it, alerting maintenance personnel to monitor the pipeline status and take appropriate measures.

[0108] Furthermore, at least two wall thickness monitoring sensors 20 are arranged at the bending position of the pipeline 50 to be tested, and the crack monitoring sensor 10 is arranged on the side of the wall thickness monitoring sensor 20 away from the bending position of the pipeline 50 to be tested.

[0109] In one embodiment, during implementation, wall thickness monitoring sensors 20 and crack monitoring sensors 10 are first installed at key locations on nuclear power pipelines, such as elbows and welds, prone to corrosion or cracking. At least two wall thickness monitoring sensors 20 are positioned at bends in the pipeline 50 to more comprehensively monitor changes in wall thickness in that area. Crack monitoring sensors 10 are positioned on the side of the wall thickness monitoring sensors 20 away from the bends in the pipeline 50. This effectively detects cracks in different locations on the pipeline, avoiding blind spots. This layout ensures comprehensive monitoring of key pipeline locations and improves the accuracy and reliability of monitoring results.

[0110] The present invention is an online monitoring system for nuclear power pipeline defects, comprising an ultrasonic thickness measurement module, a guided wave crack detection module, a data acquisition box, and a server cabinet (40). By utilizing multi-sensor fusion technology, the system utilizes the ultrasonic thickness measurement module and the guided wave crack detection module to simultaneously and regularly monitor pipeline corrosion thinning and microcracks. The system also includes a pipeline database for storing parameter information and daily monitoring data for the pipeline under test (50), providing data support for the intelligent pipeline defect analysis module. The intelligent pipeline defect analysis module extracts wall thickness and crack characteristics based on sensor data, dynamically updates remaining life curves according to relevant standards and calculation methods, generates calculation reports, and outputs warning information. The present invention enables early detection and timely treatment of pipe wall defects, effectively preventing major pipeline failures and significantly improving the safety of nuclear power pipelines.

[0111] It is understandable that the above embodiments only express the preferred implementation modes of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the patent scope of the present invention. It should be pointed out that for ordinary technicians in this field, without departing from the concept of the present invention, the above technical features can be freely combined, and several deformations and improvements can be made, all of which fall within the scope of protection of the present invention. Therefore, all equivalent changes and modifications made to the scope of the claims of the present invention should fall within the scope of coverage of the claims of the present invention.

Claims

1. A nuclear power pipeline defect online monitoring system, characterized in that: Including wall thickness monitoring sensor, crack monitoring sensor, data acquisition device and server; The data acquisition device is connected to the wall thickness monitoring sensor and the crack monitoring sensor by wires, respectively, and is used to collect wall thickness monitoring data of the monitored area of the pipeline to be tested and crack monitoring data of the monitored area of the pipeline to be tested, and transmit the data to the server; The server is in communication with the data acquisition device and is used to calculate the monitoring situation of the monitoring area according to the wall thickness monitoring data and the crack monitoring data, and output the monitoring results.

2. The nuclear power pipeline defect online monitoring system according to claim 1 is characterized in that: The server includes: A database unit, used for storing the wall thickness monitoring data and the crack monitoring data; a wall thickness calculation unit, configured to calculate a wall thickness monitoring result based on the wall thickness monitoring data; A crack calculation unit is used to calculate a crack monitoring result based on the crack monitoring data.

3. The nuclear power pipeline defect online monitoring system according to claim 2 is characterized in that: The wall thickness monitoring data includes ultrasonic echo time difference and ultrasonic sound speed, and the wall thickness calculation unit includes: a wall thickness calculation module, configured to calculate the wall thickness monitoring result of the monitoring area according to the ultrasonic echo time difference and the ultrasonic sound speed; The corrosion rate calculation module is used to calculate the wall thickness change gradient of the monitoring area according to multiple wall thickness monitoring results in time series, and eliminate noise interference through a filtering algorithm to obtain the corrosion rate of the monitoring area.

4. The nuclear power pipeline defect online monitoring system according to claim 3 is characterized in that: The crack monitoring data includes the arrival time difference of the guided wave reflection signal, the reflected wave envelope width and the guided wave mode conversion energy ratio, and the crack calculation unit includes: A crack location calculation module, configured to calculate the crack location in the monitoring area based on the arrival time difference of the guided wave reflection signal; a crack length calculation module, configured to determine the crack length at the crack location according to the reflected wave envelope width; A crack depth calculation module is used to determine the crack depth at the crack position according to the guided wave mode conversion energy ratio.

5. The nuclear power pipeline defect online monitoring system according to claim 4 is characterized in that: The database unit further stores attribute data of the pipeline to be tested; the server further comprises: A safety assessment unit, configured to substitute the property data of the pipeline to be tested and the wall thickness monitoring result into a preset stress formula to calculate an actual stress value of the pipeline to be tested; and judging whether the pipeline to be tested is safe based on the actual stress value and a preset reasonable stress value range; Wherein, the preset stress formula includes: Where S SL is the actual stress value, P is the design pressure of the pipeline, D0 is the outer diameter of the pipeline, t current is the wall thickness monitoring result, M A Resultant moment, Z is the section modulus, and i is the stress intensification factor.

6. The nuclear power pipeline defect online monitoring system according to claim 5 is characterized in that: The database unit further stores the corrosion rate and / or the average annual crack growth rate, and the server further includes: a remaining life evaluation unit, configured to calculate based on the corrosion rate and the wall thickness monitoring result to obtain a wall thickness-related remaining life; And / or, the crack-related remaining life is obtained by performing calculation based on the average annual growth rate of the storage crack and the crack length and / or the crack depth of the pipeline to be tested.

7. The nuclear power pipeline defect online monitoring system according to claim 6 is characterized in that: The calculation based on the wall thickness variation data and the wall thickness monitoring result to obtain the wall thickness related remaining life includes: Multiple iterative calculations are performed based on the wall thickness monitoring results and the corrosion rate until the calculated actual stress value does not meet the preset reasonable stress value range, thereby obtaining the wall thickness-related remaining life.

8. The nuclear power pipeline defect online monitoring system according to claim 7, characterized in that: The remaining life evaluation unit is further configured to calculate an equivalent corrected wall thickness based on the wall thickness monitoring result and the crack depth; Substituting the equivalent corrected wall thickness into the preset stress formula to obtain the remaining life of the equivalent corrected wall thickness; The minimum value is taken according to the remaining life of the equivalent corrected wall thickness and the remaining life related to the crack to obtain the comprehensive remaining life of the pipeline to be tested.

9. The nuclear power pipeline defect online monitoring system according to claim 8, characterized in that: The server further includes: An early warning unit is used to perform early warning evaluation based on different preset thresholds corresponding to the wall thickness monitoring results, and / or the crack monitoring results, and / or the wall thickness-related remaining life, and / or the crack-related remaining life, and / or the comprehensive remaining life, and output early warning evaluation information.

10. The nuclear power pipeline defect online monitoring system according to claim 9, characterized in that: At least two wall thickness monitoring sensors are arranged at the bend position of the pipeline to be measured, and the crack monitoring sensor is arranged on a side of the wall thickness monitoring sensor away from the bend position of the pipeline to be measured.

Images