Method and system for determining creep phase of nuclear power plant component based on acoustic emission

Abstract

The invention discloses a method and a system for determining a creep phase of a nuclear power plant component based on acoustic emission. The method comprises the following steps: firstly, selecting a to-be-tested component meeting a preset condition from nuclear power plant components; secondly, collecting an acoustic emission signal of the to-be-detected component; then, preprocessing the acoustic emission signal to obtain corresponding acoustic emission data; next, identifying characteristic parameters in the acoustic emission data, and generating a corresponding characteristic curve according to the characteristic parameters; and finally, comparing the characteristic curve with a preset material creep and acoustic emission relation curve, and determining the creep stage of the to-be-tested component according to a comparison result. According to the method and system for determining the creep stage of the nuclear power plant component based on acoustic emission, real-time, continuous and lossless online monitoring is carried out on the nuclear power plant component in a high-temperature and high-pressure environment so as to quickly and accurately determine the creep stage of the nuclear power plant component, so that creep damage and fracture of the nuclear power plant component are prevented, and the reliability of the nuclear power plant component is improved. And the operation safety and reliability of the nuclear power station are ensured.

Description

Technical Field

[0001] The invention relates to the field of nuclear power technology, and in particular to a method and system for determining the creep stage of nuclear power plant components based on acoustic emission. Background Art

[0002] Nuclear power structural materials and their components serve in harsh environments such as high temperature, high pressure, and irradiation. Their long-term service reliability and stability are important factors affecting the safety and reliability of nuclear power plant operation. Creep is one of the main forms of high-temperature structural damage. Under high-temperature conditions in nuclear power plants, creep deformation and damage are one of the most critical life-limiting factors for nuclear power components. Specifically, nuclear power plant components are in high temperature and high pressure conditions for a long time under operating conditions. Since some nuclear power plant components have a high stress state but have not reached the yield limit, these nuclear power plant components in high-temperature environments will produce creep deformation as the service time increases, which in turn affects the safety of the nuclear power plant components. Therefore, it is necessary to monitor the creep of nuclear power plant components to effectively prevent creep damage and rupture of nuclear power plant components. However, creep damage monitoring of nuclear power plant components is a long-term and continuous means of safe service monitoring. Due to the shortcomings of the creep expansion ruler, such as complex measurement, susceptibility to environmental influences, poor accuracy, and inability to monitor online, it cannot meet the requirements of online real-time creep monitoring of nuclear power plant components.

[0003] Patent CN110274836 discloses a creep strength test method based on acoustic emission activity analysis, including: continuously applying a constant load to a solid material specimen and collecting acoustic emission waves, setting an acoustic emission threshold value, recording the acoustic emission event rate, judging the change law of the acoustic emission event rate, and directly obtaining the creep strength of the solid material specimen. However, this method is applied in the field of petrology. Unlike nuclear power plant components that are easily affected by high temperature and high pressure environments in the nuclear power field, this method collects acoustic emission waves by applying a constant load to test the creep strength of solid materials. It is not suitable for long-term and continuous creep damage monitoring of nuclear power plant components under high temperature and high pressure. Patent CN111238940 discloses a method and system for quantitatively identifying the accelerated creep stage of rocks by acoustic emission signals, including: using acoustic emission equipment to collect acoustic emission information of the rock creep process; and real-time identification and processing of the acoustic emission signals collected by the acoustic emission equipment based on the Matlab computing platform. However, the above method also does not take into account the influence of high temperature and high pressure environments, and is not suitable for long-term and continuous creep damage monitoring of nuclear power plant components under high temperature and high pressure. Summary of the invention

[0004] The present invention aims to solve one of the above-mentioned technical problems at least to a certain extent.

[0005] To this end, the first purpose of the present invention is to propose a method for determining the creep stage of nuclear power plant components based on acoustic emission, to perform real-time, continuous, and non-destructive online monitoring of nuclear power plant components in a high temperature and high pressure environment, so as to quickly and accurately determine the creep stage of nuclear power plant components, thereby preventing creep damage and rupture of nuclear power plant components and ensuring the safety and reliability of nuclear power plant operation.

[0006] A second object of the present invention is to propose a system for determining the creep stage of nuclear power plant components based on acoustic emission.

[0007] To achieve the above-mentioned object, a first embodiment of the present invention proposes a method for determining the creep stage of nuclear power plant components based on acoustic emission, comprising:

[0008] Selecting a component to be tested that meets preset conditions from the components of the nuclear power plant, the preset conditions being that the temperature of the component is greater than or equal to a preset temperature, the stress state is a dangerous state, and the duration of the dangerous state is greater than a preset time length;

[0009] Collect the acoustic emission signal of the component to be tested;

[0010] Preprocessing the acoustic emission signal to obtain corresponding acoustic emission data;

[0011] Identify characteristic parameters in the acoustic emission data and generate corresponding characteristic curves based on the characteristic parameters;

[0012] The characteristic curve is compared with a preset material creep and acoustic emission relationship curve, and the creep stage of the component to be tested is determined based on the comparison result.

[0013] Optionally, the stress state is calculated by a nuclear power plant component stress simulation model.

[0014] Optionally, before collecting the acoustic emission signal of the component to be tested, the method further includes:

[0015] The waveguide rod and the anti-nuclear radiation probe are arranged according to the structure of the component to be tested.

[0016] Optionally, the acoustic emission signal of the component to be tested is collected, including:

[0017] Acquire the acoustic emission signals that are within the preset filtering range and trigger the acoustic emission events.

[0018] Optionally, the characteristic parameters include the cumulative number of events and the cumulative energy, the creep stage includes the initial stage, the steady-state stage and the acceleration stage, and the characteristic curve is compared with a preset material creep and acoustic emission relationship curve, and the creep stage of the component to be tested is determined according to the comparison result, including:

[0019] Determine the creep stage with the highest degree of agreement with the characteristic curve of the cumulative number of events among the three creep stages of the preset material creep and acoustic emission relationship curve as the creep stage corresponding to the cumulative number of events;

[0020] Determine the creep stage with the highest degree of agreement with the characteristic curve of cumulative energy among the three creep stages of the preset material creep and acoustic emission relationship curve as the creep stage corresponding to the cumulative energy;

[0021] The creep stage of the component to be tested is determined jointly according to the creep stage corresponding to the cumulative number of events and the creep stage corresponding to the cumulative energy.

[0022] Optionally, the method further includes:

[0023] Determine the location of creep damage based on acoustic emission data;

[0024] Safety assessment of the components to be tested is carried out according to their creep stage and creep damage location.

[0025] Applying the technical solutions in the above embodiments of the present application, the following technical effects are achieved:

[0026] 1. This method conducts real-time, continuous, and non-destructive online monitoring of nuclear power plant components in high temperature and high pressure environments, and can quickly and accurately determine the creep stage of nuclear power plant components, thereby effectively preventing creep damage and rupture of nuclear power plant components and ensuring the safety and reliability of nuclear power plant operation.

[0027] 2. This method takes into account the influence of high temperature, high pressure and radiation environment in nuclear power plants on the creep of nuclear power plant components, as well as the stress changes of nuclear power plant components caused by high temperature, high pressure and radiation environment, and the influence of vibration and noise sources on the acquisition of acoustic emission signals, and accurately selects the components to be tested through preset conditions.

[0028] 3. When collecting the acoustic emission signal of the component to be tested, this method performs bandwidth filtering on the acoustic emission signal emitted by the component to be tested, and then quickly and accurately collects the acoustic emission signal that triggers the acoustic emission event according to a determined threshold.

[0029] 4. This method jointly determines the creep stage of the component to be tested in real time and dynamically through at least two characteristic curves, thereby improving the accuracy of creep stage judgment in creep monitoring.

[0030] To achieve the above-mentioned object, the second embodiment of the present invention proposes a system for determining the creep stage of nuclear power plant components based on acoustic emission, comprising: a component to be tested, a waveguide rod, a nuclear radiation resistant probe and a data acquisition system;

[0031] The waveguide rod is fixedly connected to one end of the component to be tested;

[0032] The anti-nuclear radiation probe is arranged on the other end of the waveguide rod;

[0033] The data acquisition system is installed outside the containment of the nuclear power plant and is connected to the anti-nuclear radiation probe;

[0034] The system for determining the creep stage of a nuclear power plant component based on acoustic emission is used for executing a method for determining the creep stage of a nuclear power plant component based on acoustic emission.

[0035] Optionally, the data acquisition system includes an acoustic emission signal processing device and an analysis system;

[0036] The acoustic emission signal processing device is connected to the anti-nuclear radiation probe;

[0037] The analysis system is connected to the acoustic emission signal processing equipment.

[0038] Optionally, the waveguide rod is connected to the component to be tested by welding.

[0039] Optionally, the system also includes: a main control room monitoring system, which is connected to the analysis system.

[0040] Applying the technical solutions in the above embodiments of the present application, the following technical effects are achieved:

[0041] 1. The system can control the anti-nuclear radiation probe to accurately collect the acoustic emission signal of the component to be tested through the acoustic emission signal processing equipment.

[0042] 2. The system can guide and transmit the acoustic emission signal in the component to be tested to the anti-nuclear radiation probe through the waveguide rod, and can effectively reduce the impact of high temperature on the anti-nuclear radiation probe through the waveguide rod.

[0043] 3. The system implements a method for determining the creep stage of nuclear power plant components based on acoustic emission, which can determine the creep stage of the components to be tested in real time, dynamically and comprehensively, further improving the accuracy of creep stage judgment in creep monitoring, thereby effectively preventing creep damage and rupture of nuclear power plant components and ensuring the safety and reliability of nuclear power plant operation.

[0044] 4. The system can receive the creep stage and creep damage position of the component to be tested determined by the analysis system to comprehensively analyze and evaluate the safety of the component to be tested.

[0045] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0047] Figure 1 A flow chart of a method for determining the creep stage of a nuclear power plant component based on acoustic emission according to an embodiment is shown;

[0048] Figure 2 A schematic diagram of a preset material creep stage according to an embodiment is shown;

[0049] Figure 3 A flow chart of a method for determining the creep stage of a nuclear power plant component based on acoustic emission according to another embodiment is shown;

[0050] Figure 4 A schematic diagram of the spatial distribution of waveguide rods and anti-nuclear radiation probes in an embodiment is shown. Figure 1 ;

[0051] Figure 5 A schematic diagram of the spatial distribution of waveguide rods and anti-nuclear radiation probes in an embodiment is shown. Figure 2 ;

[0052] Figure 6 A schematic diagram of the spatial distribution of waveguide rods and anti-nuclear radiation probes in an embodiment is shown. Figure 3 ;

[0053] Figure 7 A flow chart of a method for determining the creep stage of a nuclear power plant component based on acoustic emission according to another embodiment is shown;

[0054] Figure 8 A schematic structural diagram of a system for determining the creep stage of nuclear power plant components based on acoustic emission according to an embodiment is shown;

[0055] Fig. 9 A schematic structural diagram of a system for determining the creep stage of nuclear power plant components based on acoustic emission according to another embodiment is shown.

[0056] Figure numerals: 100, component to be tested; 200, waveguide rod; 300, anti-nuclear radiation probe; 400, data acquisition system; 410, acoustic emission signal processing equipment; 420, analysis system; 500, nuclear power plant containment; 600, main control room monitoring system. DETAILED DESCRIPTION

[0057] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0058] The present invention is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed by the present invention.

[0059] The following describes a method and system for determining the creep stage of a nuclear power plant component based on acoustic emission according to an embodiment of the present invention with reference to the accompanying drawings.

[0060] Figure 1 1 is a flow chart of a method for determining the creep stage of a nuclear power plant component based on acoustic emission according to an embodiment of the present invention, which specifically includes the following steps:

[0061] S1, select the components to be tested that meet the preset conditions from the nuclear power plant components.

[0062] The preset conditions are that the temperature of the nuclear power plant components is greater than or equal to the preset temperature, the stress state is a dangerous state, and the duration of the dangerous state is greater than the preset time length.

[0063] In one embodiment of the present invention, a temperature sensor is used to measure the temperature of a nuclear power plant component. When the temperature of a nuclear power plant component is greater than or equal to a preset temperature and continues to operate at a state greater than or equal to the preset temperature, it means that the nuclear power plant component needs to consider the creep effect. It should be noted that the preset temperature corresponding to different nuclear power plant components is determined according to its creep starting temperature and the actual application environment. For example, if the temperature of a ferrite component in a nuclear power plant exceeds 371°C and the creep effect needs to be considered, 371°C is used as the preset temperature of the ferrite component; if the temperature of an austenite component in a nuclear power plant exceeds 427°C and the creep effect needs to be considered, 427°C is used as the preset temperature of the austenite component; if the temperature of a nickel-based alloy component in a nuclear power plant exceeds 427°C and the creep effect needs to be considered, 427°C is used as the preset temperature of the nickel-based alloy component.

[0064] The stress state is calculated by the stress simulation model of nuclear power plant components. Specifically, the stress simulation calculation model is used to perform mechanical analysis and calculation on the nuclear power plant components under the corresponding actual operating conditions to obtain the position of the nuclear power plant components in the stress concentration section, and the stress state of the nuclear power plant components in the stress concentration section is determined to be a dangerous state. In a specific embodiment, based on the simulation analysis software, a mechanical analysis is performed on the simulation model under actual operating conditions. According to the calculation results, when the creep assessment item reaches 80% or more of the corresponding limit value, the corresponding position can be determined to be in a dangerous state.

[0065] Furthermore, mechanical analysis and calculation are continued for the nuclear power plant component whose stress state is in a dangerous state. If the time duration of the nuclear power plant component's stress state in a dangerous state is greater than a preset time duration, the nuclear power plant component is determined as a component to be tested.

[0066] It should be noted that by determining the stress state of nuclear power plant components, the components to be tested can be effectively located, so that acoustic emission data can be subsequently collected under constant load or near constant load conditions, ensuring the pertinence and reliability of damage monitoring during the creep process of nuclear power plant components.

[0067] Therefore, according to the above conditions, the nuclear power plant components whose temperature is greater than or equal to the preset temperature, whose stress state is a dangerous state and whose duration of the dangerous state is greater than the preset time length are determined as the components to be tested.

[0068] The above process takes into account the impact of high temperature, high pressure and radiation environment in nuclear power plants on the creep of nuclear power plant components, as well as the stress changes of nuclear power plant components caused by high temperature, high pressure and radiation environment. Based on preset conditions, it realizes the precise selection of the components to be tested and the corresponding position determination, providing a guarantee for obtaining accurate acoustic emission signals during the subsequent creep monitoring of nuclear power plant components.

[0069] S2, collecting the acoustic emission signal of the component to be tested.

[0070] Specifically, an acoustic emission signal that is within a preset filtering range and triggers an acoustic emission event is collected.

[0071] In one embodiment of the present invention, since the component to be tested selected by S1 will undergo creep damage under a long-term stress state, the stress wave signal emitted due to creep damage inside the component to be tested, i.e., the acoustic emission signal, can be utilized to realize passive, dynamic, and real-time non-destructive testing, thereby achieving the purpose of long-term, continuous online monitoring of nuclear power plant components.

[0072] Specifically, considering that the background noise intensity is different under different temperatures and stress states when the nuclear power plant components are continuously monitored for creep, and because the background noise intensity may exceed the acoustic emission signal intensity, background filtering is performed to eliminate noise interference, and an appropriate threshold is selected to collect the acoustic emission signal that triggers the acoustic emission event.

[0073] It should be understood that when continuous creep monitoring is performed on nuclear power plant components, acoustic emission signals are collected at a fixed unit time length (such as day or hour).

[0074] On the one hand, the short-time signal emitted by the component to be tested is picked up in the actual operating environment and the frequency composition of the short-time signal is analyzed, and the component to be tested is simulated by finite element software to obtain the natural frequency of its structure, and then the filter range is pre-set according to the frequency analysis result and the natural frequency of the component to be tested, so that the bandwidth filtering can be realized quickly and accurately when the acoustic emission signal is collected based on the filter range, thereby effectively filtering out the noise interference and improving the quality and clarity of the acoustic emission signal. On the other hand, the threshold value of triggering the acoustic emission event under different temperatures and different stress states is determined by uniaxial tensile creep test, so as to determine the corresponding threshold value according to the temperature and stress state of the component to be tested during the actual operation of the nuclear power plant.

[0075] Therefore, when collecting the acoustic emission signal of the component to be tested, after bandwidth filtering is performed on the acoustic emission signal emitted by the component to be tested, the acoustic emission signal that triggers the acoustic emission event is quickly and accurately collected according to the threshold determined by the uniaxial tensile creep test.

[0076] S3, preprocessing the acoustic emission signal to obtain corresponding acoustic emission data.

[0077] In one embodiment of the present invention, the acoustic emission signals collected by S2 are preprocessed to obtain corresponding acoustic emission data, so as to provide support for subsequent identification and analysis work.

[0078] S4, identifying characteristic parameters in the acoustic emission data, and generating corresponding characteristic curves according to the characteristic parameters.

[0079] Specifically, the characteristic parameters in the acoustic emission data obtained by preprocessing in S3 are identified, and corresponding characteristic curves are generated according to the characteristic parameters. For example, the number of events and the cumulative number of events, the energy and the cumulative energy have different activities at different stages of creep, and corresponding distribution curves can be generated; the event rate and energy rate reflect the current creep damage degree and damage rate, and corresponding trend curves can be generated.

[0080] Therefore, qualitative analysis of the creep stage can be performed quickly and accurately in creep monitoring of nuclear power plant components according to the characteristic curve.

[0081] S5, comparing the characteristic curve with a preset material creep and acoustic emission relationship curve, and determining the creep stage of the component to be tested according to the comparison result.

[0082] Among them, the creep stage includes the initial stage, the steady-state stage and the acceleration stage.

[0083] It should be noted that by conducting indoor creep and acoustic emission relationship tests under different working conditions of the tested components under the same or similar temperature and stress conditions as the actual creep monitoring, the following can be obtained: Figure 2 The preset material creep stage curve shown in FIG. Wherein, I represents the initial stage, II represents the steady-state stage, III represents the acceleration stage, t represents time, and ε represents strain.

[0084] In one embodiment of the present invention, the characteristic parameters include the cumulative number of events and the cumulative energy. The stress wave signal, i.e., the acoustic emission signal, is emitted from the interior of the component to be tested due to creep damage. At the same time, since there are more internal damages in the initial stage and the acceleration stage, the amount of internal damage of the component to be tested is larger, so the activity of the cumulative number of events and the cumulative energy increases significantly. Therefore, the preset material creep stage curve (such as Figure 2The characteristic curve of the cumulative number of events generated by S4 is compared with the characteristic curve of the cumulative number of events generated by S4, and the creep stage with the highest degree of agreement with the characteristic curve of the cumulative number of events among the three creep stages of the preset material creep and acoustic emission relationship curve is determined as the creep stage corresponding to the cumulative number of events. Among them, the change trend of the creep stage with the highest degree of agreement with the characteristic curve of the cumulative number of events among the three creep stages of the preset material creep and acoustic emission relationship curve is the best consistent with the change trend of the characteristic curve of the cumulative number of events.

[0085] In addition, the preset material creep stage curve (such as Figure 2 The characteristic curve of the accumulated energy generated by S4 is compared to determine the creep stage with the highest degree of agreement with the characteristic curve of the accumulated energy among the three creep stages of the preset material creep and acoustic emission relationship curve as the creep stage corresponding to the accumulated energy.

[0086] Then, the creep stage of the component to be tested can be determined based on the creep stage corresponding to the cumulative number of events and the creep stage corresponding to the cumulative energy. Specifically, if the creep stage corresponding to the cumulative number of events and the creep stage corresponding to the cumulative energy are the same, the same creep stage is determined to be the creep stage of the component to be tested; if the creep stage corresponding to the cumulative number of events and the creep stage corresponding to the cumulative energy are different, the sampling unit length and the threshold for collecting and triggering acoustic emission events are adjusted according to the temperature and pressure deviation between the actual creep monitoring environment and the test to reacquire the acoustic emission signal, so as to determine the creep stage corresponding to the cumulative number of events and the creep stage corresponding to the cumulative energy again, until the creep stage corresponding to the cumulative number of events and the creep stage corresponding to the cumulative energy are the same.

[0087] In a specific embodiment, if the creep stage cannot be determined, the sampling time interval is first adjusted by ±10% and the determination is made again; if the determination still cannot be made, the signal threshold is adjusted by ±10% and the creep determination is made; if the determination still cannot be made, the operator checks and determines according to the actual situation.

[0088] Therefore, the creep stage of the component to be tested can be jointly determined in real time and dynamically through the cumulative event number distribution curve and the cumulative energy distribution curve, thereby improving the accuracy of creep stage judgment in creep monitoring.

[0089] In another embodiment, Figure 3 As shown, before collecting the acoustic emission signal of the component to be tested, it also includes:

[0090] S6, setting the waveguide rod and the anti-nuclear radiation probe according to the structure of the component to be tested.

[0091] In one embodiment of the present invention, the number and position of the waveguide rods 200 and the probes are arranged according to the arrangement structure of the component to be tested 100, and a certain spatial distribution configuration is adopted to facilitate the subsequent determination of the creep damage position. Figures 4 to 6 As shown, for different arrangements or structures of components to be tested, such as containers, straight pipes, curved pipes, or components including tees, brackets, valves, etc., different numbers and arrangements of waveguide rods 200 or probes are used to improve the accuracy of the collected acoustic emission data and meet the subsequent positioning requirements of the creep damage area.

[0092] In yet another embodiment, Figure 7 As shown, it also includes:

[0093] S7, determining the creep damage location based on the acoustic emission data.

[0094] In one embodiment of the present invention, the active position of creep damage is determined quickly and accurately based on the acoustic emission data of the component to be tested after S3 preprocessing and in combination with the position of the waveguide rod or the probe.

[0095] S8, performing safety assessment on the component to be tested according to the creep stage and creep damage location of the component to be tested.

[0096] In one embodiment of the present invention, a comprehensive and accurate safety assessment is performed on the component to be tested based on the creep stage of the component to be tested determined by S5 and the creep damage position determined by S7, and the safety of the component to be tested is comprehensively analyzed and assessed, so as to timely determine the creep damage of the component to be tested, avoid affecting the safety of nuclear power plant component operation due to creep deformation of the component to be tested, and ensure the stability and reliability of nuclear power plant operation.

[0097] Applying the technical solutions in the above embodiments of the present application, the following technical effects are achieved:

[0098] 1. This method conducts real-time, continuous, and non-destructive online monitoring of nuclear power plant components in high temperature and high pressure environments, and can quickly and accurately determine the creep stage of nuclear power plant components, thereby effectively preventing creep damage and rupture of nuclear power plant components and ensuring the safety and reliability of nuclear power plant operation.

[0099] 2. This method takes into account the influence of high temperature, high pressure and radiation environment in nuclear power plants on the creep of nuclear power plant components, as well as the stress changes of nuclear power plant components caused by high temperature, high pressure and radiation environment, and the influence of vibration and noise sources on the acquisition of acoustic emission signals, and accurately selects the components to be tested through preset conditions.

[0100] 3. When collecting the acoustic emission signal of the component to be tested, this method performs bandwidth filtering on the acoustic emission signal emitted by the component to be tested, and then quickly and accurately collects the acoustic emission signal that triggers the acoustic emission event according to a determined threshold.

[0101] 4. This method jointly determines the creep stage of the component to be tested in real time and dynamically through at least two characteristic curves, thereby improving the accuracy of creep stage judgment in creep monitoring.

[0102] In order to implement the above embodiments, the present invention also proposes a system for determining the creep stage of nuclear power plant components based on acoustic emission.

[0103] Figure 8 It is a structural schematic diagram of a system for determining the creep stage of nuclear power plant components based on acoustic emission according to an embodiment of the present invention.

[0104] like Figure 8 As shown, the system for determining the creep stage of nuclear power plant components based on acoustic emission includes: a component to be tested 100 , a waveguide rod 200 , an anti-nuclear radiation probe 300 and a data acquisition system 400 .

[0105] The waveguide rod 200 is fixedly connected to one end of the component to be tested 100 , and the anti-nuclear radiation probe 300 is arranged on the other end of the waveguide rod 200 .

[0106] In a specific embodiment of the present invention, the waveguide rod 200 is welded to the component to be tested 100. Furthermore, a coupling agent, such as vaseline, is applied to the weld. Thus, the acoustic emission signal in the component to be tested 100 can be transmitted in real time and stably through the waveguide rod 200. In addition, the component to be tested is a high-temperature component, and the waveguide rod can effectively reduce the influence of high temperature on the anti-nuclear radiation probe.

[0107] In this embodiment, the data acquisition system 400 is disposed outside the containment vessel 500 of the nuclear power plant, and the data acquisition system is connected to the anti-nuclear radiation probe 300 .

[0108] In a specific embodiment of the present invention, the data acquisition system includes an acoustic emission signal processing device 410 and an analysis system 420. The acoustic emission signal processing device 410 is connected to the anti-nuclear radiation probe 300, and can control the anti-nuclear radiation probe 300 to collect acoustic emission signals within a preset filtering range and triggering an acoustic emission event through the acoustic emission signal processing device, and pre-process the collected acoustic emission signals. In addition, the analysis system 420 is connected to the acoustic emission signal processing device 410, and is used to analyze the pre-processed acoustic emission data to determine the creep stage and creep damage position of the component to be tested.

[0109] In this embodiment, the system for determining the creep stage of nuclear power plant components based on acoustic emission is used to execute the method for determining the creep stage of nuclear power plant components based on acoustic emission in the previous embodiment, which can determine the creep stage of the components to be tested in real time, dynamically and comprehensively, further improving the accuracy of creep stage judgment in creep monitoring, thereby effectively preventing creep damage and destruction of nuclear power plant components and ensuring the safety and reliability of nuclear power plant operation.

[0110] In another embodiment, Fig. 9As shown, the system for determining the creep stage of nuclear power plant components based on acoustic emission also includes: a main control room monitoring system 600.

[0111] Specifically, the main control room monitoring system 600 is connected to the analysis system 420 to receive the creep stage and creep damage position of the component to be tested determined by the analysis system 420 to comprehensively analyze and assess the safety of the component to be tested. In a specific embodiment, the analysis system 420 is embedded in the main control room monitoring system 600.

[0112] Applying the technical solutions in the above embodiments of the present application, the following technical effects are achieved:

[0113] 1. The system can control the anti-nuclear radiation probe to accurately collect the acoustic emission signal of the component to be tested through the acoustic emission signal processing equipment.

[0114] 2. The system can guide and transmit the acoustic emission signal in the component to be tested to the anti-nuclear radiation probe through the waveguide rod, and can effectively reduce the impact of high temperature on the anti-nuclear radiation probe through the waveguide rod.

[0115] 3. The system implements a method for determining the creep stage of nuclear power plant components based on acoustic emission, which can determine the creep stage of the components to be tested in real time, dynamically and comprehensively, further improving the accuracy of creep stage judgment in creep monitoring, thereby effectively preventing creep damage to nuclear power plant components and ensuring the safety and reliability of nuclear power plant operation.

[0116] 4. The system can receive the creep stage and creep damage position of the component to be tested determined by the analysis system to comprehensively analyze and evaluate the safety of the component to be tested.

[0117] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0118] It should be noted that, in the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

Claims

1. A method for determining the creep stage of nuclear power plant components based on acoustic emission, characterized in that: include: Selecting a component to be tested that meets preset conditions from the nuclear power plant components, wherein the preset conditions are that the temperature of the nuclear power plant component is greater than or equal to a preset temperature, the stress state is a dangerous state, and the duration of the dangerous state is greater than a preset time length; Collecting the acoustic emission signal of the component to be tested; Preprocessing the acoustic emission signal to obtain corresponding acoustic emission data; Identifying characteristic parameters in the acoustic emission data, and generating corresponding characteristic curves according to the characteristic parameters; The characteristic curve is compared with a preset material creep and acoustic emission relationship curve, and the creep stage of the component to be tested is determined according to the comparison result.

2. The method according to claim 1, characterized in that The stress state is calculated by a nuclear power plant component stress simulation model.

3. The method according to claim 1, characterized in that Before collecting the acoustic emission signal of the component to be tested, the method further includes: The waveguide rod and the anti-nuclear radiation probe are arranged according to the structure of the component to be tested.

4. The method according to claim 1, characterized in that: Collecting the acoustic emission signal of the component to be tested includes: Acquire the acoustic emission signals that are within the preset filtering range and trigger the acoustic emission events.

5. The method according to claim 1, characterized in that: The characteristic parameters include the cumulative number of events and the cumulative energy. The creep stage includes the initial stage, the steady-state stage and the acceleration stage. The characteristic curve is compared with a preset material creep and acoustic emission relationship curve. The creep stage of the component to be tested is determined according to the comparison result, including: Determine the creep stage with the highest degree of agreement with the characteristic curve of the cumulative number of events among the three creep stages of the preset material creep and acoustic emission relationship curve as the creep stage corresponding to the cumulative number of events; Determine the creep stage with the highest degree of agreement with the characteristic curve of the cumulative energy among the three creep stages of the preset material creep and acoustic emission relationship curve as the creep stage corresponding to the cumulative energy; The creep stage of the component to be tested is determined jointly according to the creep stage corresponding to the accumulated number of events and the creep stage corresponding to the accumulated energy.

6. The method according to claim 1, characterized in that Also includes: determining a creep damage location based on the acoustic emission data; A safety assessment is performed on the component to be tested according to the creep stage and the creep damage position of the component to be tested.

7. A system for determining the creep stage of nuclear power plant components based on acoustic emission, characterized in that: include: A component to be tested, a waveguide rod, an anti-nuclear radiation probe and a data acquisition system, wherein the waveguide rod is fixedly connected to one end of the component to be tested; The anti-nuclear radiation probe is arranged on the other end of the waveguide rod; The data acquisition system is arranged outside the containment of the nuclear power plant, and the data acquisition system is connected to the anti-nuclear radiation probe; The system for determining the creep stage of a nuclear power plant component based on acoustic emission is used to execute the method for determining the creep stage of a nuclear power plant component based on acoustic emission as described in any one of claims 1-6.

8. The system according to claim 7, characterized in that The data acquisition system includes an acoustic emission signal processing device and an analysis system, The acoustic emission signal processing device is connected to the anti-nuclear radiation probe; The analysis system is connected to the acoustic emission signal processing device.

9. The system according to claim 7, characterized in that The waveguide rod is connected to the component to be tested by welding.

10. The system according to claim 8, characterized in that Also includes: A main control room monitoring system is connected to the analysis system.

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