Nuclear-grade pressure-bearing pipeline failure monitoring method and electronic equipment

Abstract

The invention discloses a nuclear-grade pressure-bearing pipeline failure monitoring method and electronic equipment, and belongs to the technical field of nondestructive testing. The monitoring method comprises the following steps: constructing a standard component sample, wherein the standard component sample comprises a plurality of standard components; multi-axis asymmetrically loaded loads are circularly applied to the standard parts, and the cyclic load times of all the standard parts are different; collecting a first nonlinear correlation coefficient of each standard component; establishing a standard curve according to the cyclic loading times of each standard component and the first nonlinear correlation coefficient; acquiring cyclic loading times of the to-be-tested piece, and acquiring a second nonlinear correlation coefficient of the to-be-tested piece; acquiring a first nonlinear correlation coefficient of the to-be-tested piece under the cyclic loading times according to the cyclic loading times and the standard curve; and according to the second nonlinear correlation coefficient and the first nonlinear coefficient of the to-be-tested piece, judging whether the material of the to-be-tested piece is invalid or not. According to the monitoring method and the electronic equipment provided by the invention, the failure state of the pipeline can be monitored online in real time.

Description

Technical Field

[0001] The present invention relates to the technical field of nondestructive testing, and particularly to a method for monitoring the failure of nuclear-grade pressure-bearing pipelines and an electronic device. Background Art

[0002] As a core component for the safe operation of nuclear power plants, the failure of nuclear-grade pressure-bearing pipelines can lead to nuclear accidents such as radioactive leakage and reactor shutdown. Therefore, it is necessary to monitor the failure of nuclear-grade pressure-bearing pipelines to ensure nuclear safety and prevent catastrophic accidents. During the failure process of nuclear-grade pressure-bearing pipelines, ratchet deformation and fatigue failure are two different failure modes. Currently, monitoring methods often independently monitor the damage caused by ratchet deformation and fatigue failure to the pipelines. However, in the actual application of nuclear-grade pressure-bearing pipelines, ratchet deformation and fatigue failure are interrelated and jointly contribute to the pipeline failure. Therefore, the current monitoring methods have the problem of inaccurate monitoring results. Summary of the Invention

[0003] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a method for monitoring the failure of nuclear-grade pressure-bearing pipelines and an electronic device, which can perform real-time and online monitoring of the failure of pipelines under the interaction of ratchet deformation and fatigue failure, and improve the accuracy of monitoring results.

[0004] To solve the above technical problems, the present invention is realized through the following technical solutions.

[0005] The present invention provides a method for monitoring the failure of nuclear-grade pressure-bearing pipelines, which at least includes the following steps:

[0006] Construct a standard part sample, the standard part sample includes a plurality of standard parts, and the material of the standard parts is the same as that of the nuclear-grade pressure-bearing pipeline;

[0007] Loop to execute the instruction of applying a multi-axial asymmetric loading load on the standard parts, and the number of cyclic loads of each standard part is different;

[0008] Collect the first non-linear correlation coefficient of each standard part;

[0009] Establish a standard curve according to the number of cyclic loads and the first non-linear correlation coefficient of each standard part;

[0010] Obtain the number of cyclic loads of the part to be tested, and collect the second non-linear correlation coefficient of the part to be tested;

[0011] According to the number of cyclic loads and the standard curve, obtain the first non-linear correlation coefficient of the part to be tested at the number of cyclic loads; and

[0012] Judge whether the material of the test piece fails according to the magnitudes of the second non-linear correlation coefficient and the first non-linear coefficient of the test piece.

[0013] In an embodiment of the present invention, under a preset temperature and a preset pressure, the load is cyclically applied to the standard piece at a preset strain rate.

[0014] In an embodiment of the present invention, the preset temperature is 400°C - 1200°C, the preset pressure is 15 MPa - 17 MPa, and the preset strain rate is 50 / S - 100 / S.

[0015] In an embodiment of the present invention, during the multi-axial asymmetric loading, the loading waveform is a sine wave, a triangular wave or a square wave, the mean stress is 40 MPa - 80 MPa, the stress amplitude is 500 MPa - 600 MPa, and the stress ratio is 0.2 - 0.6.

[0016] In an embodiment of the present invention, on all the standard pieces, the number of cycles of the cyclic load is increased from 0 times to at least 1000 times.

[0017] In an embodiment of the present invention, the first non-linear correlation coefficient of the standard piece is the second-order non-linear coefficient obtained by performing non-linear ultrasonic detection on the standard piece, and the second non-linear correlation coefficient of the test piece is the second-order non-linear coefficient obtained by performing non-linear ultrasonic detection on the test piece.

[0018] In an embodiment of the present invention, during the non-linear ultrasonic detection process, the amplitudes of the fundamental wave and the second harmonic are collected, and the second-order non-linear coefficient is obtained according to the following formula:

[0019]

[0020] where β’ is the second-order non-linear coefficient, A1 is the amplitude of the fundamental wave, and A2 is the amplitude of the second harmonic.

[0021] In an embodiment of the present invention, the number of cycles of the cyclic loading is obtained by the rain-flow counting method or the maximum-minimum counting method.

[0022] In an embodiment of the present invention, after obtaining the first non-linear correlation coefficient of the test piece, the damage factor of the test piece is obtained according to the following formula:

[0023] D = β” 待测件 / β 待测件 ,

[0024] where D is the damage factor, β” 待测件 is the second non-linear correlation coefficient of the test piece, and β 待测件It is the first non - linear correlation coefficient of the component under test under the number of cyclic loadings.

[0025] In an embodiment of the present invention, when the damage factor is greater than or equal to 1, it is determined that the material of the component under test fails.

[0026] In an embodiment of the present invention, the material of the component under test is the same as the material of the standard component.

[0027] The present invention also provides an electronic device, which at least includes:

[0028] A memory;

[0029] A processor for executing a computer program stored in the memory to implement the monitoring method for the failure of nuclear - level pressure - bearing pipelines as described above; and

[0030] A communication bus connecting the memory and the processor.

[0031] In summary, the present invention provides a monitoring method and an electronic device for the failure of nuclear - level pressure - bearing pipelines. Based on the interaction between ratchet deformation and fatigue failure, it accurately judges and evaluates whether the pipeline material fails, so as to improve the operation safety of nuclear - level pressure - bearing pipelines and reduce the probability of nuclear accidents. Moreover, the monitoring method and the electronic device for the failure of nuclear - level pressure - bearing pipelines provided by the present invention can monitor the failure state of nuclear - level pressure - bearing pipelines in the operating conditions in real - time and online, and further provide data support for determining the pipeline maintenance cycle and replacement cycle.

[0032] Of course, it is not necessary to achieve all the above - mentioned advantages simultaneously when implementing any aspect of the present invention. Description of the Drawings

[0033] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following - described drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0034] Figure 1 It is a flowchart of the monitoring method for the failure of nuclear - level pressure - bearing pipelines in an embodiment of the present invention.

[0035] Figure 2 It is a modal amplitude ratio relationship diagram.

[0036] Figure 3 It is Figure 1 A schematic diagram of the standard curve in Detailed Embodiments

[0037] The following specific examples are used to illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0038] It should be understood that the present invention can be implemented in different forms and should not be construed as limited to the embodiments presented herein. On the contrary, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of the present invention to those skilled in the art.

[0039] The technical solution of the present invention will be further described in detail below in conjunction with the embodiments and the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0040] Please refer to Figures 1 to 3 As shown, the present invention provides a method for monitoring the failure of nuclear-grade pressure-bearing pipelines, which can perform real-time and on-line monitoring of the failure of pipelines under the interaction of ratcheting deformation and fatigue failure, and improve the accuracy of monitoring results. Moreover, the monitoring method provided by the present invention can be applied to the failure monitoring of pipelines in various factories such as chemical plants or nuclear power plants. In this embodiment, taking the monitoring of the failure of nuclear-grade pressure-bearing pipelines as an example, the monitoring method will be described. Specifically, the monitoring method includes steps S11 - S17, for example.

[0041] Step S11: Construct a standard part sample, which includes a plurality of standard parts, and the materials of the standard parts are the same as those of the nuclear-grade pressure-bearing pipelines.

[0042] Step S12: Loop to execute the instruction of applying a multi-axial asymmetric loading load on the standard parts, and the number of cyclic loads of each standard part is different.

[0043] Step S13: Collect the first non-linear correlation coefficient of each standard part.

[0044] Step S14: Establish a standard curve according to the number of cyclic loads and the first non-linear correlation coefficient of each standard part.

[0045] Step S15: Obtain the number of cyclic loads of the part to be tested, and collect the second non-linear correlation coefficient of the part to be tested.

[0046] Step S16: Obtain the first non - linear correlation coefficient of the component under test at the cyclic loading times according to the cyclic loading times and the standard curve.

[0047] Step S17: Determine whether the material of the component under test fails according to the magnitudes of the second non - linear correlation coefficient and the first non - linear coefficient of the component under test.

[0048] Please refer to Figure 1 As shown, in an embodiment of the present invention, in step S11, the materials, shapes and sizes of multiple standard components are completely the same, and the materials of the standard components are the same as those of the nuclear - class pressure - bearing pipelines. The materials include at least one of austenitic stainless steel, nickel - based alloy, low - alloy steel, zirconium alloy, etc., to ensure that the nuclear - class pressure - bearing pipelines can operate safely for a long time in extreme environments such as high temperature, high pressure and strong radiation. Among them, the present application does not limit the shapes and sizes of individual standard components, which can be set according to actual needs. In this embodiment, taking the standard component as a cylindrical shape as an example, the monitoring method is described.

[0049] Please refer to Figure 1As shown, in an embodiment of the present invention, after obtaining the standard parts, in step S12, at a preset temperature and a preset pressure, at a preset strain rate, for example, by means of a multiaxial testing machine, etc., a load of multiaxial asymmetric loading is cyclically applied to each standard part, and the number of cycles of the load applied to each standard part, that is, the number of cyclic loadings N, is different. Among them, the preset temperature is, for example, 400°C - 1200°C, the preset pressure is, for example, 15 MPa - 17 MPa, the preset strain rate is, for example, 50 / s - 100 / s. In multiaxial asymmetric loading, the loading waveform is, for example, a sine wave, a triangular wave or a square wave, etc., the mean stress is, for example, 40 MPa - 80 MPa, the stress amplitude is, for example, 500 MPa - 600 MPa, the stress ratio is, for example, 0.2 - 0.6. On all the standard parts, the number of cyclic loadings N increases from at least 0 times to 1000 times, specifically, for example, it increases to 10000 times or 50000 times, etc., and the increasing amplitude of the number of cyclic loadings is, for example, 20 times - 200 times, specifically, for example, 50 times or 100 times, etc. During the multiaxial asymmetric loading process, plastic strain is generated in the standard parts, resulting in irreversible dislocation slip, forming dislocation accumulation, and thus ratcheting deformation occurs. At the same time, the microstructure of the standard part material changes, for example, dislocation monopoles, dislocation loops and dislocation dipoles are formed, generating a large number of dislocation groups. With the accumulation of the dislocation groups, persistent slip bands are caused, and then microcracks are formed. As the microcracks grow and expand, macro-cracks are formed, and thus fatigue failure occurs. Among them, due to the accumulation of plastic strain in ratcheting deformation, the local wall thickness of the standard part is thinned, and the stress amplitude increases, which will accelerate the generation of cracks in fatigue failure, that is, ratcheting deformation can promote the occurrence of fatigue failure. On the contrary, due to the generation of cracks in fatigue failure, the stiffness of the standard part material decreases, and the plastic strain in ratcheting deformation is more likely to occur, that is, fatigue failure can promote the occurrence of ratcheting deformation. Therefore, ratcheting deformation and fatigue failure act synergistically to jointly damage the material of the standard part. Moreover, since the number of cyclic loadings of each standard part is different, the damage degree of each standard part material is different, and thus multiple standard parts with different damage degrees can be obtained through step S12.

[0050] Please refer to Figure 1As shown, in an embodiment of the present invention, after obtaining a plurality of standard parts with different degrees of damage, in step S13, for example, a non-linear ultrasonic testing system is used to perform non-linear ultrasonic detection on each standard part to obtain the first non-linear correlation coefficient β of each standard part, and the degree of damage of the standard part is quantified by the first non-linear correlation coefficient β. Among them, the non-linear ultrasonic testing system is, for example, Olympus EPOCH 650 or Beijing Zhongke Innovation Technology Development Center HS800, etc. Specifically, the non-linear ultrasonic system emits a fundamental wave excitation signal with a single frequency into the standard part. The fundamental wave propagates in the standard part and has a non-linear interaction with cracks and dislocations in the standard part material, generating second harmonics and third harmonics. Among them, the amplitude of the fundamental wave is, for example, A1, the amplitude of the second harmonic is, for example, A2, and the second-order non-linear coefficient and the second-order non-linear coefficient β' is defined as the first non-linear correlation coefficient β. The amplitude of the third harmonic is, for example, A3, and the third-order relative non-linear coefficient The curves of the amplitudes of the fundamental wave, second harmonic, and third harmonic changing with frequency, that is, the modal amplitude ratio, are as Figure 2 shown. It can be seen from Figure 2 that under a single-frequency excitation, as the frequency of the harmonic component increases, the amplitude of the higher-order harmonic component decreases, and the second-order non-linear coefficient and the third-order non-linear coefficient are proportional to the modal amplitude ratio. Compared with linear ultrasonic detection, non-linear ultrasonic detection is more sensitive to damages such as cracks and dislocations in materials, can accurately detect the degree of damage in materials, and accurately reflect it on the second-order non-linear coefficient β', that is, the first non-linear correlation coefficient β.

[0051] Please refer to Figures 1 to 3 As shown, in an embodiment of the present invention, after obtaining the first non-linear correlation coefficient β of each standard part, in step S14, with the number of cyclic loads N of the standard part as the abscissa and the first non-linear correlation coefficient β as the ordinate, a standard curve between the number of cyclic loads N and the first non-linear correlation coefficient β is obtained. Among them, as the number of cyclic loads N of the standard part increases, the first non-linear correlation coefficient β increases, indicating that: the first non-linear correlation coefficient β is positively correlated with the degree of damage of the standard part material. Since the number of cyclic loads N of the standard part increases from 0 times to at least 1000 times, involving a relatively large number of cycles, the standard curve can describe the ratcheting deformation-fatigue failure interaction of the standard part material under the full life cycle and be used as the basis for judging whether the subsequent material fails.

[0052] Please refer to Figure 1As shown, in an embodiment of the present invention, after obtaining the standard curve, in step S15, a test piece is provided. The test piece is, for example, a nuclear-grade pressure-bearing pipeline in a nuclear power plant. As the operating cycle of the nuclear-grade pressure-bearing pipeline in the nuclear power plant extends, the pipeline material will inevitably be damaged to varying degrees. Therefore, it is necessary to quantify the damage degree of the pipeline material to determine the service life and replacement cycle of the pipeline and prevent nuclear accidents from occurring.

[0053] Please refer to Figure 1 As shown, in an embodiment of the present invention, after obtaining the test piece, in step S15, first, data on the variation of loads such as stress, strain, or pressure with time during the operation of the test piece is monitored in real time and online through sensors. Then, the cyclic loading times n of the test piece are obtained through data processing methods such as the rain-flow counting method or the maximum-minimum counting method. In this embodiment, taking the rain-flow calculation method as an example, the process of obtaining the cyclic loading times n is described. Specifically, by simulating the flow path of raindrops, closed cycles are extracted from the load-time variation data to obtain the cyclic loading times n. By monitoring the load variation of the test piece in real time through sensors and then performing data processing, the cyclic loading times n of the test piece at any moment during operation can be obtained in real time and online, thus facilitating the subsequent real-time judgment of the failure state of the test piece material.

[0054] Please refer to Figure 1 As shown, in an embodiment of the present invention, after obtaining the cyclic loading times n, in step S15, for example, the test piece in the operating condition is subjected to non-linear ultrasonic detection in real time through an online monitoring system, the second-order non-linear coefficient β' of the test piece is detected in real time and online, and the second-order non-linear coefficient β' of the test piece is defined as the second non-linear correlation coefficient β". 待测件 . Specifically, the online monitoring system is connected to the test piece. The online monitoring system includes, for example, a non-linear ultrasonic system and a data processing module. The non-linear ultrasonic system is, for example, Olympus EPOCH 650 or Beijing Zhongke Innovation Technology Development Center HS800, etc. The non-linear ultrasonic system is connected to the test piece to perform real-time non-linear ultrasonic detection on the test piece and output the second-order non-linear coefficient. The data processing module is communicatively connected to the non-linear ultrasonic system to record and store the second-order non-linear times β' output by the non-linear ultrasonic system. Among them, the process of obtaining the second-order non-linear coefficient β' of the test piece is the same as the process of obtaining the second-order non-linear coefficient β' of the standard piece in step S13, and will not be elaborated here.

[0055] Please refer to Figures 1 to 3 As shown, in an embodiment of the present invention, the second non-linear correlation coefficient β" is obtained 待测件After that, in step S16, in the standard curve, identify the first non-linear correlation coefficient β corresponding to the number of cyclic loadings n of the component under test, and obtain the first non-linear correlation coefficient β of the component under test at the number of cyclic loadings n.

[0056] Please refer to Figure 1 As shown, in an embodiment of the present invention, to obtain the first non-linear correlation coefficient β 待测件 After that, in step S17, calculate the damage factor of the component under test according to the following formula:

[0057] D = β” 待测件 / β 待测件 ,

[0058] where D is the damage factor, and β” 待测件 is the second non-linear correlation coefficient of the component under test, and β 待测件 is the first non-linear correlation coefficient of the component under test at the number of cyclic loadings n.

[0059] Please refer to Figure 1 As shown, in an embodiment of the present invention, after obtaining the damage factor D, in step S17, determine whether the material of the component under test has failed according to the damage factor D. Specifically, when the damage factor D is greater than or equal to 1, the second non-linear correlation coefficient β” 待测件 is greater than or equal to the first non-linear correlation coefficient β 待测件 , indicating that the damage in the material of the component under test is relatively severe and the material has failed, and the component under test needs to be repaired or replaced. On the contrary, when the damage factor D is less than 1, the second non-linear correlation coefficient β” 待测件 is less than the first non-linear correlation coefficient β 待测件 , indicating that the damage in the material of the component under test is relatively light and the component under test can still be used. Since the number of cyclic loadings n at any moment during the operation of the component under test can be obtained in real time and online in step S15, and the second non-linear correlation coefficient β” of the component under test can be monitored in real time and online in step S16 待测件 , so that the damage factor D of the component under test at any moment during the operation can be calculated in real time with the real-time data of the number of cyclic loadings n and the second non-linear correlation coefficient β” 待测件 , thus enabling the real-time judgment of the failure state of the material of the component under test during operation without affecting the online operation of the component under test, providing data support for determining the maintenance period and replacement period of the component under test, and further improving the safety of the operation of nuclear-grade pressure-bearing pipelines and reducing the probability of nuclear accidents.

[0060] Based on the above monitoring method for the failure of nuclear-grade pressure-bearing pipelines, the present invention also provides an electronic device, including a memory, a processor, a communication bus, etc. Among them, the memory stores a computer program of the above monitoring method, and the processor is used to execute the computer program stored in the memory to implement the above monitoring method for the failure of nuclear-grade pressure-bearing pipelines. The communication bus connects the memory and the processor to realize signal transmission between the memory and the processor.

[0061] In summary, the present invention provides a monitoring method and an electronic device for the failure of nuclear-grade pressure-bearing pipelines. Based on the interaction between ratchet deformation and fatigue failure, it accurately judges and evaluates whether the pipeline material fails, so as to improve the operation safety of nuclear-grade pressure-bearing pipelines and reduce the probability of nuclear accidents. Moreover, the monitoring method and the electronic device for the failure of nuclear-grade pressure-bearing pipelines provided by the present invention can monitor the failure state of nuclear-grade pressure-bearing pipelines in the operating conditions in real time and online, and further provide data support for determining the pipeline maintenance cycle and replacement cycle.

[0062] The embodiments of the present invention disclosed above are only used to help illustrate the present invention. The embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and variations can be made according to the content of this specification. These embodiments are selected and specifically described in this specification to better explain the principle and practical application of the present invention, so that those skilled in the art can understand and utilize the present invention well. The present invention is only limited by the claims and their full scope and equivalents.

Claims

1. A monitoring method for the failure of nuclear-grade pressure-bearing pipelines, characterized in that, At least include the following steps: Construct a standard part sample, the standard part sample includes a plurality of standard parts, and the material of the standard part is the same as that of the nuclear-grade pressure-bearing pipeline; Loop to execute the instruction of applying a multi-axial asymmetric loading load on the standard part, and the number of cyclic loads of each standard part is different; Collect the first non-linear correlation coefficient of each standard part; Establish a standard curve according to the number of cyclic loads and the first non-linear correlation coefficient of each standard part; Obtain the number of cyclic loads of the test piece to be measured, and collect the second non-linear correlation coefficient of the test piece to be measured; According to the number of cyclic loads and the standard curve, obtain the first non-linear correlation coefficient of the test piece to be measured under the number of cyclic loads; And Judge whether the material of the test piece to be measured fails according to the magnitudes of the second non-linear correlation coefficient and the first non-linear coefficient of the test piece to be measured.

2. The monitoring method according to claim 1, wherein Under a preset temperature and a preset pressure, cyclically apply the load on the standard part at a preset strain rate.

3. The monitoring method according to claim 2, wherein The preset temperature is 400°C - 1200°C, the preset pressure is 15 MPa - 17 MPa, and the preset strain rate is 50 / s - 100 / s.

4. The monitoring method according to claim 1, wherein When performing multi-axial asymmetric loading, the loading waveform is a sine wave, a triangular wave or a square wave, the mean stress is 40 MPa - 80 MPa, the stress amplitude is 500 MPa - 600 MPa, and the stress ratio is 0.2 - 0.

6.

5. The monitoring method according to claim 1, characterized in that, On all standard parts, the number of cyclic loads increases from 0 times to at least 1000 times.

6. The monitoring method according to claim 1, wherein, The first non-linear correlation coefficient of the standard part is the second-order non-linear coefficient obtained by performing non-linear ultrasonic detection on the standard part, and the second non-linear correlation coefficient of the test piece to be measured is the second-order non-linear coefficient obtained by performing non-linear ultrasonic detection on the test piece to be measured.

7. The monitoring method according to claim 6, characterized in that During the non-linear ultrasonic detection process, collect the amplitudes of the fundamental wave and the second harmonic, and obtain the second-order non-linear coefficient according to the following formula: where β’ is the second-order non-linear coefficient, A1 is the amplitude of the fundamental wave, and A2 is the amplitude of the second harmonic.

8. The monitoring method according to claim 1, characterized in that, The number of cyclic loads is obtained by the rainflow counting method or the maximum-minimum counting method.

9. The monitoring method according to claim 1, characterized in that, After obtaining the first non-linear correlation coefficient of the test piece to be measured, obtain the damage factor of the test piece to be measured according to the following formula: D＝β” 待测件 / β 待测件 ， where D is the damage factor, and β” 待测件 is the second non-linear correlation coefficient of the test piece, and β 待测件 is the first non-linear correlation coefficient of the test piece under the cyclic loading times.

10. The monitoring method according to claim 9, wherein, When the damage factor is greater than or equal to 1, judge that the material of the test piece to be measured fails.

11. The monitoring method according to claim 1, characterized in that, The material of the test piece to be measured is the same as the material of the standard part.

12. An electronic device, characterized in that, At least include: A memory; A processor for executing the computer program stored in the memory to implement the monitoring method for the failure of the nuclear-grade pressure-bearing pipeline as described in any one of claims 1 - 11; and A communication bus connecting the memory and the processor.

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